text:
\section{Introduction}

X-ray emission is an ubiquitous signature of accretion, and can be observed in a wide range of astrophysical phenomena, from protoplanetary disks (e.g., \citealp{Feigelson:1999fv,Kastner:2002re}), to X-ray binaries  (e.g., \citealp{Remillard:2006pn}) and massive black holes (e.g., \citealp{Rees:1984cm,Mushotzky:1993ei}). This X-ray radiation can be strongly affected by the interstellar medium (ISM; e.g., \citealp{Ryter:1975ka,Schattenburg:1986rq,Willingale:2013fm}), and a good understanding of the effect of the ISM on the X-ray spectra of cosmic sources is crucial to both accurately constrain their intrinsic X-ray properties and to shed light on the characteristics of the ISM itself.

The ISM is composed by material in different phases: atomic, molecular and dust (e.g., \citealp{Wilms:2000vn}), and its cross-section is the sum of these three components: $\sigma_{\rm ISM}=\sigma_{\rm atomic} + \sigma_{\rm molecular} + \sigma_{\rm dust}$. Depending on its phase, the gas can have different effects on the X-ray radiation. About half of the hydrogen in the Galaxy is in atomic form, but it is not uniformly distributed \citep{Shull:1982vk}, and typically a molecular gas fraction of $f_{\rm H2}\simeq20\%$ is assumed (e.g., \citealp{Wilms:2000vn}), although in some clouds this value could be significantly higher (e.g., $f_{\rm H2}\simeq50-70\%$; \citealp{Shull:2021gk}). In the Milky Way about 1\% of the mass of the ISM is in form of dust (e.g., \citealp{Bohlin:1978bv}), a similar value is found in other galaxies with consistent metallicity (e.g., \citealp{Remy-Ruyer:2014hp}). Dust grains form from metals in the ISM, depleting them from the gas phase (e.g., \citealp{Savage:1996vh}). Depletion can be inverted when dust is destroyed, for example by blast waves from supernovae (e.g., \citealp{Jones:1994io}) or by dust sublimation (e.g., \citealp{Suganuma:2006id}). Dust participates in the different phases of the galaxy growth process. Dust grains are fundamental for gas cooling (e.g., \citealp{Schneider:2002ai,Omukai:2005sf}), which is a crucial step in the process of stellar and planet formation. Dust is also very important for the feedback process in galaxies, allowing the ISM to react to the radiation emitted by star-forming regions \citep{Murray:2005zb} or by accreting supermassive black holes (SMBHs) at relatively low values of the Eddington ratio (e.g., \citealp{Fabian:2008yd,Fabian:2009zj,Ricci:2017sj,Ricci:2022ay}).

Dust can play an important role in the X-rays (e.g., \citealp{Wilms:2000vn,Draine:2003kb,Lee:2009gb,Costantini:2022ff}), absorbing and scattering X-ray photons. Since photoelectric absorption in the X-rays is associated to metals, having $\sim 70\%$ or more of the metals locked into the dust grains (e.g., \citealp{Wilms:2000vn}) can strongly affect the absorption process. Dust scattering is preferentially in the forward direction, which can lead to the production of diffuse halos around X-ray sources (e.g., \citealp{Rolf:1983rr}). These halos have been routinely studied over the past two decades in X-ray binaries (e.g., \citealp{Costantini:2005bx,Corrales:2015ew}), and have also been proposed as a tool to test dust models (e.g., \citealp{Smith:2006ua,Seward:2013yi}) and to measure distance of nearby galaxies (e.g., \citealp{Draine:2004zt}). The presence of dust in the ISM can also leave a clear imprint on X-ray spectra, particularly around some of the main edges. The interference pattern created by the photoelectron waves during the absorption of a X-ray photon in dust grains can in fact give rise to X-ray absorption fine structures (XAFS). These features are expected to be commonly associated to Mg, Si and O (e.g., \citealp{Costantini:2019cr,Rogantini:2019hv,Rogantini:2020lj,Psaradaki:2020tt,Zeegers:2017qe,Zeegers:2019lu}), and have been identified in the X-ray spectra of X-ray bright Galactic sources thanks to high-resolution {\it XMM-Newton} and {\it Chandra} observations (e.g., \citealp{Lee:2002bk,Lee:2010ot,Ueda:2005pp,de-Vries:2009wi,Kaastra:2009xi,Pinto:2010hn,Pinto:2013vh,Costantini:2012bi,Valencic:2013ay,Psaradaki:2022hh}). The presence of dust in the ISM could lead to significant biases when measuring the column density in the direction of X-ray sources with models that do not consider dust absorption and scattering \citep{Corrales:2016bq,Smith:2016ad}.

Most of the current X-ray models do not include dust. Notable exceptions are the widely used \textsc{tbabs} family of models \citep{Wilms:2000vn}, which however do not consider scattered radiation, and the \textsc{amol} \citep{Pinto:2010hn}, \textsc{dabs} \citep{Wilms:2000vn,Kaastra:2009xi} and \textsc{dust} \citep{Draine:2003kb} models, that are part of the \textsc{SPEX} package \citep{Kaastra:1996pf}. The \textsc{SPEX} models are based on a large effort to measure the main X-ray properties of dust in the X-ray band \citep{Costantini:2013xw}, and currently represent the state-of-the-art. However, these absorption models do not allow for complex geometries, which are often needed to reproduce all the complex features observed in the X-ray spectra of astrophysical sources. The advent of the high spectral resolution instruments on-board {\it XRISM} (Resolve, \citealp{XRISM-Science-Team:2020fo}) and {\it Athena} (X-IFU, \citealp{Barret:2016ij}) will require improved models, which include all the relevant physical processes, taking into account reprocessed radiation as well as absorbed emission, and that consider realistic geometries of the material around X-ray sources. In this work we report on the implementation of dust absorption and scattering in the ray-tracing platform \textsc{RefleX}\footnote{https://www.astro.unige.ch/reflex/} \citep{Paltani:2017fa}, which allows to create self-consistent physical models of the environment of X-ray sources including dusty gas.

\section{The new version of RefleX}\label{sec:reflex}

\textsc{RefleX} \citep{Paltani:2017fa} is a versatile ray-tracing code that allows to perform X-ray simulations over a wide range of energies (0.1\,keV--1\,MeV), considering quasi-arbitrary geometries that can be set by the user. \textsc{RefleX}\ allows to create complex models, that can be applied to a variety of astrophysical phenomena (e.g., \citealp{Liu:2019wv,Andonie:2022rs,McKaig:2022sj}). In the first two releases, \textsc{RefleX}\ included most of the physical processes relevant to radiation in the X-ray band, such as photoelectric absorption, fluorescence, Compton scattering on free electrons, Rayleigh scattering, Compton scattering on bound electrons and polarization.

\subsection{Dusty gas in \textsc{RefleX}}\label{sec:reflex_dust1}

The new version of the code (\textsc{RefleX}\ 3.0) includes the propagation of X-ray photons in a dusty medium. The parameters defining dust are however even more numerous than those defining the properties of the gas phase. Indeed dust is not only defined by the densities of the different atoms, but also by the types of molecules and crystalline structures, as well as the full distribution of grain sizes. Recent analyses \citep{Hensley2021} point towards extremely complex dust compositions in our galaxy. It would however be pointless to implement such a huge complexity in \textsc{RefleX} , considering that the parameter space is too large to allow us to have meaningful constraints outside of the Milky Way. For this reason, only a simple, fixed dust model is considered within \textsc{RefleX} , which includes nevertheless all the physical processes associated to the presence of dust.

\begin{table*}[t!]
\begin{center}
\caption{Depletion of different elements for the abundances adopted by \textsc{RefleX} : \textsc{aneb} \citep{Anders:1982yk}, \textsc{angr} \citep{Anders:1989ce},  \textsc{aspl} \citep{Asplund:2009ly},  \textsc{feld} \citep{Feldman:1992mc},  \textsc{grsa} \citep{Grevesse:1998zy},  \textsc{lodd} \citep{Lodders:2003vy},  \textsc{lpgp} \citep{Lodders:2009vs}, \textsc{lpgs} \citep{Lodders:2009vs}, and \textsc{wilm} \citep{Wilms:2000vn}. The depletions are reported by considering the maximum values of \textsc{dust}. The \textsc{cosmic} and \textsc{void} abundances are not reported, since dust depletion is zero for all elements. The elements not listed in the table are not depleted from the gas phase.}
\label{tab:depletion}
\begin{tabular}{lccccccccc}
\hline
\hline
\noalign{\smallskip}

Element	&  \textsc{aneb}  &  \textsc{angr}  &  \textsc{aspl}  &  \textsc{feld}  &  \textsc{grsa}  &  \textsc{lodd}  &  \textsc{lpgp}  &  \textsc{lpgs}  &  \textsc{wilm}  \\
   &	 	[\textsc{dust 1}]	&	 	[\textsc{dust 0.759}]&	 	[\textsc{dust 1}]&	 	[\textsc{dust 1}]&	 	[\textsc{dust 1}]&	 	[\textsc{dust 1}]&	 	[\textsc{dust 1}]&	 	[\textsc{dust 1}]&	 	[\textsc{dust 0.691}] \\
\noalign{\smallskip}
\hline
\noalign{\smallskip}
C		& 0.298 &  0.391 &  0.470 &  0.326 &  0.382 &  0.482 &  0.460 &  0.471 &  0.310 \\
O		& 0.179 &  0.167 &  0.258 &  0.152 &  0.187 &  0.241 &  0.210 &  0.216 &  0.152 \\
Mg		& 0.834 &  0.935 &  0.794 &  0.853 &  0.832 &  0.831 &  0.813 &  0.822 &  0.741 \\
Si		& 0.899 &  1.000 &  0.975 &  0.913 &  0.943 &  0.850 &  0.852 &  0.847 &  1.000 \\
Fe		& 1.000 &  0.759 &  1.000 &  1.000 &  1.000 &  1.000 &  1.000 &  1.000 &  0.691 \\
\noalign{\smallskip}
\hline
\noalign{\smallskip}
\end{tabular}
\end{center}
\end{table*}

The implementation of dust in \textsc{RefleX}\ follows \citet{Draine:2003kb}. Dust is considered as a mix of Carbon grain in graphite crystalline structure and of olivine silicate grains [Mg$_{2x}$Fe$_{2(1-x)}$SiO$_4$]. According to \citet{Draine:2003kb}, Mg and Fe are both equally represented in the dust phase of the Milky Way, thus olivine is globally in the form MgFeSiO$_4$. In addition, there is about four Carbon atoms in the dust phase for each Silicon atom \citep{Draine:2003kb}. The grain size distributions for graphite and olivine adopted in \citet{Draine:2003kb} have been derived by \cite{Weingartner:2001eb} for the Milky Way. These distributions are in the form of a power law with indices $-1.54$ for graphite and $-2.21$ for olivine starting at 3.5\,\AA\ with a modified cut-off at 0.01 and 0.164\,$\mu$m, respectively. In addition, the graphite distribution presents two additional log-normal components centered at 3.5 and 30\,\AA\ respectively. The adopted densities of graphite and silicate grains are 2.24 and 3.5 g\,cm$^{-3}$, respectively.  In \textsc{RefleX} , dust is governed by a single parameter (\textsc{dust}) that provides the fraction of iron in the dust phase compared to the total number of iron atoms. We will refer to this parameter as {\it dust depletion} in the following. \textsc{dust 1} means that all iron atoms are in the dust phase, so that none remains in the gas phase.  We note that compositions in \textsc{RefleX}\ can be set arbitrarily, and for certain abundances \textsc{dust} cannot reach one because some of the elements in the dust are fully depleted. For example, the maximum value allowed by \textsc{RefleX}\ for abundances from \citet{Anders:1989ce} and \citet{Wilms:2000vn} is \textsc{dust 0.759} and \textsc{dust 0.691}, respectively, for which Silicon is fully depleted. For an Iron depletion of 0.7, the depletion of Silicon is 0.9 in \citet{Wilms:2000vn}, while it is one in our dust model; this is due to a larger fraction of Fe$_2$SiO$_4$ compared to Mg$_2$SiO$_4$ in our dust with respect to the model of \citet{Wilms:2000vn}. It should be noted that \textsc{RefleX}\ calculates the maximum dust depletion, and will not allow the user to set a higher value of the \textsc{dust} parameter. Unless stated otherwise, throughout the paper we will use the proto-solar abundances of \citeauthor{Lodders:2009vs} (\citeyear{Lodders:2009vs}; \textsc{lpgs}). With these abundances, Carbon, Oxygen, Magnesium, and Silicon are abundant enough that all Iron atoms can be put in the dust phase (\textsc{dust 1}). This is in agreement with recent observational studies, which found that most of the iron in the ISM is found in dust (e.g., \citealp{Psaradaki:2022hh}). The depletion of the different elements found in the dust grains considered here, for different abundances and for the maximum values of \textsc{dust} allowed, are reported in Table\,\ref{tab:depletion}.

\begin{figure}
\begin{center}
\includegraphics[width=7cm]{grain.ps}
\caption{\label{fig:grain_sketch}Sketch of the process of self-absorption of fluorescence emitted in a large grain (see \S\ref{sec:reflex_dust2}). Photons coming from the right are more likely to be absorbed in the part of the grain shown in blue, which represents schematically the mean free path for these photons. Both photons ($\gamma_1$ and $\gamma_2$) are absorbed (green stars) and fluorescence photons $\varphi_1$ and $\varphi_2$ are emitted in both cases in random directions. Photon $\varphi_1$ crosses more material than $\varphi_2$, and is more likely to be absorbed in the dust grain. Similarly, the sketch also illustrates the process of shielding (\S\ref{sec:reflex_dust2}), in which low-energy photons that hit a dust grain are absorbed in the outer part of the grain, and do not ``see'' the atoms in the center or the other side of the grain.}
\end{center}\end{figure}

\begin{figure*}
\includegraphics[width=8.8cm]{hist_C.ps}
\includegraphics[width=8.8cm]{hist_Si.ps}
\caption{Angular distributions of fluorescence photons emitted by Carbon (left panel) and Silicon (right panel) in a dust grain illuminated by 0.3\,keV (C) or 2\,keV (Si) photons for different grain radii: 0.1$\mu$m (red line), 1$\mu$m (purple line) and 5$\mu$m (blue line). The black line shows the angular distribution for an isotropic source of radiation. An angle of $-90^{\circ}$ means that the photon direction is opposite to that of the incoming photons. The histograms are normalised to peak at unity.}\label{fig:grain_angular}
\end{figure*}

\begin{figure*}
\centering
\includegraphics[width=0.49\textwidth]{Photoelectric_CS.ps}
\includegraphics[width=0.49\textwidth]{Dust_CS.ps}
\par\smallskip
\includegraphics[width=0.49\textwidth]{Dust_CS_noscatt.ps}
\includegraphics[width=0.49\textwidth]{All_CS_dust1.ps}
\caption{Different cross-sections of gas used in \textsc{RefleX} . {\it Top left panel:} photoelectric cross-section for gas with no dust (continuous grey line), and dust depletion 0.3 (green dot-dot-dashed line), 0.5 (blue dashed line) and 1 (red dotted line). {\it Top right panel:} same as the top left panel for the dust cross section. {\it Bottom left panel:} same as the top right panel excluding dust scattering. {\it Bottom right panel:} Total cross section of dusty gas for \textsc{dust 1} (black solid line), together with the contribution of photoelectric absorption (long-dashed green line), Rayleigh scattering (dashed cyan line), Compton scattering (dotted red line), and dust (dot-dot-dashed orange line). The proto-solar abundances of \citet{Lodders:2009vs} were considered to calculate the cross-sections. The spectral resolution was set to 10\,eV.}
\label{fig:crosssections}
\end{figure*}

\subsection{New physical processes included}\label{sec:reflex_dust2}

Three physical processes are specific to the presence of dust in the X-rays, and are implemented in \textsc{RefleX} :
\begin{itemize}
	\item \textbf{Scattering on dust grains.} While Rayleigh scattering can be considered as scattering on particles of sizes of the same order of magnitude as, or smaller than, the wavelength of the incoming photon, dust particles are significantly larger than the photon wavelength, but not so large that scattering becomes normal optical reflection. Scattering on dust is described by Mie \citep{Wiscombe:1980aa} and anomalous diffraction (ADT; \citealp{van-de-Hulst:1957fg}) theory. For dust grains of radii $a$, Mie theory is used for $2\pi a/\lambda<2\times10^4$, while ADT is considered for $2\pi a/\lambda>2\times10^4$. Dust scattering is elastic, and mostly forward, with the median scattering angle decreasing as the photon energy increases (Eq.\,\ref{eq:scatteringangle}). The cross-sections and differential cross-section used here are taken from \citet{Draine:2003kb}.
	\item \textbf{NEXAFS} (Near-Edge X-ray Absorption Fine Structure). The crystalline arrangement of the atoms in dust grains affects the photo-ionization absorption cross-sections near the X-ray edges very close to the transition energy. The precise cross-sections can be computed using the GGADT code \citep{Hoffman:2016po} for any dust composition, shape and size, and could constitute a diagnostic of the precise dust content using very sensitive X-ray spectrometers, like the X-IFU instrument \citep{Barret2018} on the future X-ray mission Athena \citep{Barcons2017}. The photo-ionization absorption cross-sections in dust used in \textsc{RefleX}\ are also obtained from \citet{Draine:2003kb}, which includes the effect of NEXAFS.
	\item \textbf{Shielding}. Self-shielding is another process that affects the photo-ionization absorption cross-sections of dust, and is the effect by which some atoms are hidden from X-ray radiation. This is due to the fact that atoms in dust are very strongly clustered in grains. Therefore, low-energy photons that hit a dust grain will be absorbed in the front part of the grain, and will never ``see'' the atoms on the other side of the grain (see Fig.\,\ref{fig:grain_sketch}). The effect of shielding is to decrease the photo-ionization absorption cross-sections at low energies ($\lesssim 3$\,keV); at higher energies ($\gtrsim 3$\,keV), for the dust grain sizes considered here, shielding is minimal (e.g., \citealp{Wilms:2000vn}). Shielding is implemented in the cross-sections of \citet{Draine:2003kb} that are used in \textsc{RefleX} .
\end{itemize}

Dust could also affect the process of fluorescence. Fluorescence from dusty gas could be expected in different astrophysical environments around bright X-ray sources, such as for example a torus around accreting supermassive black holes (e.g., \citealp{Antonucci93,Netzer:2013ix,Ramos-Almeida:2017hw}).
When a photon is absorbed in an optically-thick grain, absorption will not occur uniformly in the grain, but it will happen more likely close to the surface of the grain. Fluorescent photons are emitted isotropically. However, when a fluorescence photon is created inside a dust grain, the path length through the grain will depend on the direction of the reemitted photon, and there would some directions where the fluorescence photon has more chance of being reabsorbed immediately, which would affect the observed angular distribution of fluorescent photons. This is illustrated in Fig.~\ref{fig:grain_sketch}. The effect depends on the size of the grain and the energy of the photons, and will be negligible for the smallest grains. In order to establish the importance of this effect, we simulated using \textsc{RefleX}\ a single grain that we illuminate with X-rays, and checked the direction of outgoing fluorescence photons. We performed a number of simulations of single Carbon and Silicon grains with different photon energies and grain sizes. Figure~\ref{fig:grain_angular} shows the angular distributions of fluorescence photons (mostly C\,K$\alpha$ and Si\,K$\alpha$) in the case of grains illuminated by 0.3\,keV (C) or 2\,keV (Si) photons for spherical grains with radius 0.1\,$\mu$m, 1\,$\mu$m, and 5\,$\mu$m, respectively. Here we focus primarily on dust grain in the ISM and, at sizes of the order of the maximum grain size in our adopted distribution, no deviation from an isotropic distribution is observed; however, for larger grains, the vast majority of photons are emitted backwards, as expected. We conclude that, for the ISM grains considered here, this effect is insignificant, and thus it is not implemented in \textsc{RefleX}. We point out that this result is not unexpected, as the fluorescence photons are emitted below their respective edge energies, and encounter therefore significantly lower photo-electric cross-sections. We discuss in detail in \S\ref{sec:fluorescent} the relation between dust depletion and the production of fluorescent lines.

\begin{figure*}[t]
\centering
\includegraphics[width=0.49\textwidth]{Photoelectric_ratio.ps}
\includegraphics[width=0.49\textwidth]{Total_ratio_onlydustscatt.ps}
\includegraphics[width=0.49\textwidth]{Total_ratio.ps}
\includegraphics[width=0.49\textwidth]{Total_ratio_nodustscatt.ps}
\caption{Ratio of the cross-sections with and without dust used in \textsc{RefleX}\ considering different dust depletions. {\it Top left panel:} ratio between the photoelectric cross section assuming different dust depletion and that of non-dusty gas.  {\it Top right panel:} ratio between the scattering cross-section (i.e., Rayleigh, Compton and dust) of dusty and non-dusty gas. {\it Bottom right panel:} ratio between the total cross-section of dusty gas and that of non-dusty gas. {\it Bottom left panel:} ratio between the total cross-section of dusty gas without dust scattering and that of non-dusty gas. The proto-solar abundances of \citet{Lodders:2009vs} were considered to calculate the cross-sections. The spectral resolution was set to 10\,eV.}
\label{fig:ratio_crosssections}
\end{figure*}

\begin{figure*}
\centering
\includegraphics[width=0.49\textwidth]{Plot_phabs_RefleX_ALL.ps}
\includegraphics[width=0.49\textwidth]{Plot_tbabs_RefleX_ALL.ps}
\caption{\textsc{RefleX} simulations versus the two most commonly used absorption models available in \textsc{xspec}. The simulations were carried out assuming that the absorbing material is distributed in a slab, considering different line-of-sight column densities ($10^{22}$, $10^{23}$ and $10^{24}\rm\,cm^{-2}$), and a spectral resolution of 5\,eV. {\it Left panel}: \textsc{RefleX} simulations (red lines) versus \textsc{phabs} (grey lines). For consistency, in our simulations dust was not considered, the molecular gas fraction was set to zero, and we turned off fluorescence, Rayleigh and Compton scattering. {\it Right panel}: \textsc{RefleX} simulations (red lines) versus \textsc{tbabs} (grey lines). For consistency, dust depletion was set to \textsc{dust 0.7}, while the molecular gas fraction to $f_{\rm H2}=20\%$, and the simulations ignored fluorescence, Compton scattering, as well as dust scattering.}
\label{fig:phabs_tbabs}
\end{figure*}
\subsection{Cross sections of dusty gas}\label{sec:crosssectionsdust}

We illustrate in Fig.\,\ref{fig:crosssections} the cross-sections of gas for different dust depletions. In the top left panel we show the photo-electric cross-section, which decreases as the dust depletion increases because of the increasing amount of metals in the dust grains. This effect is clearly illustrated in the top left panel of Fig.\,\ref{fig:ratio_crosssections}, which shows the ratio between the photoelectric cross-section of dusty and non-dusty gas, for different depletions. At the maximum dust depletion, the photoelectric cross-section decreases up to a factor $\sim 4$ with respect to the non-dusty gas case. The cross-section of dust is shown in the top-right panel of Fig.\,\ref{fig:crosssections} for three values of depletion, while in the bottom-left panel we show the dust cross-section without scattering. As expected, the cross-section increase with the dust depletion, as more metals are found in dust grains. Comparing the two figures it is clear that dust scattering contributes significantly to the overall dust cross-section.
In the bottom-right panel we show the total cross section of dusty gas for \textsc{dust 1} (black solid line), together with the contribution of different cross-sections (i.e., photoelectric, Rayleigh, Compton and dust), over a broad range of energies (0.3--200\,keV). Dust plays a strong effect below 10\,keV (see also top right panel of Fig.\,\ref{fig:ratio_crosssections}), and dominates the overall cross-section in the $\sim 3-10$\,keV range. Above $\sim$10\,keV Compton scattering dominates the interaction between photons and gas.

In the bottom right panel of Fig.\,\ref{fig:ratio_crosssections} we show the ratio between the total cross-section of dusty gas and that of non-dusty gas [$\sigma/\sigma(\textsc{dust 0})$]. The strong increase in the cross-section of dusty gas, with the ratio reaching $\sim 2.5$ around the Fe edge at $\sim 7$\,keV, is driven by the contribution of dust scattering. Since dust scattering is preferentially forward, and the scattering angles are typically rather small, this process does not lead to strong changes in the X-ray spectra, although some photons could be lost, while it could give rise to scattering halos (see \S\ref{sec:dusthalo}). The very large contribution of dust grains to the overall scattering cross section is shown in the top right panel of Fig.\,\ref{fig:ratio_crosssections}. To better assess the effect of dust we show, in the bottom left panel of Fig.\,\ref{fig:ratio_crosssections}, $\sigma/\sigma(\textsc{dust 0})$ when excluding dust scattering. The figure illustrates clearly the effect of shielding (\S\ref{sec:reflex_dust2}), which can lead to $\sigma/\sigma(\textsc{dust 0})<1$, particularly at energies $\lesssim 3$\,keV. This effect produces a decrease in the number of photons that are absorbed at low energy by dusty gas with respect to non-dusty gas. Another effect that is clear from the figure is the strong increase of the cross-section around the edges of elements that are found in dust (i.e., C, O, Si, Fe), due to the presence of NEXAFS (\S\ref{sec:reflex_dust2}).

\section{Comparison with photoelectric absorption models}\label{sec:reflexvstbabs}

\textsc{RefleX}\ was thoroughly tested in \citet{Paltani:2017fa}, where we compared the results of our simulations to several existing X-ray spectral models, considering different geometries of the reprocessing material, and discussed about the differences, which are due to the larger number of physical processes included into \textsc{RefleX}. In order to further validate this new version of the code, we briefly compare here the new version of \textsc{RefleX}\ to two of the most-used existing photoelectric absorption models within \textsc{XSPEC} \citep{Arnaud:1996kx}: \textsc{phabs} (\S\ref{sect:phabs}) ad \textsc{tbabs} (\S\ref{sect:tbabs}). In these simulations we assume a primary X-ray continuum in the form of a power-law with a photon index of $\Gamma=1.9$.

\subsection{PHABS}\label{sect:phabs}
We start by benchmarking our simulations with \textsc{phabs}, which considers photoelectric absorption from neutral gas. Therefore, in our \textsc{RefleX}\ simulations dust was not considered (\textsc{dust 0}), and the molecular gas fraction was set to zero (\textsc{h2fraction 0}). Moreover, to be consistent with the model, our simulations ignored fluorescence, Rayleigh and Compton scattering, which are otherwise included by default in \textsc{RefleX}. This was done by using a functionality of \textsc{RefleX}\ that allows to turn off some of the physical processes\footnote{\textsc{physics fluor off, physics rayleigh off, physics compton off}}. The abundance was set to be the same in both the \textsc{RefleX}\ simulations and the \textsc{xspec} model (\textsc{wilm}; \citealp{Wilms:2000vn}).
The results of our simulations (red line), together with those obtained using \textsc{phabs} (grey line), are shown in the left panel of Fig.\,\ref{fig:phabs_tbabs} for three different values of column density: $N_{\rm H}=10^{22}$, $10^{23}$ and $10^{24}\rm\,cm^{-2}$. The agreement between the \textsc{RefleX}\ simulations and the spectral model is perfect, regardless of the column density.

\subsection{TBABS}\label{sect:tbabs}

\textsc{tbabs} \citep{Wilms:2000vn} considers absorption by dust grains, and therefore dust depletion was set to \textsc{dust 0.7} in our \textsc{RefleX}\ simulations. To be consistent with the assumption of the model, we set the molecular gas fraction to $f_{\rm H2}=20\%$, and used the abundances from \citet{Wilms:2000vn}. Since \textsc{tbabs} does not consider fluorescence, Compton and dust scattering, we turned off all these physical processes\footnote{\textsc{physics fluor off, physics rayleigh off, physics compton off, physics dust\_scat off.}}. The comparison between our simulations and \textsc{tbabs} is shown in the right panel of Fig.\,\ref{fig:phabs_tbabs} for three different values of column density. While at $N_{\rm H}\sim 10^{23}-10^{24}\rm\,cm^{-2}$ there is an excellent agreement, our \textsc{RefleX}\ simulations show weaker absorption at $10^{22}\rm\,cm^{-2}$. This difference is associated to the different grain sizes considered in the two codes, which results in a different impact of shielding (\S\ref{sec:reflex_dust2}). The grain size adopted in \textsc{RefleX}\ follows \citeauthor{Draine:2003kb} (\citeyear{Draine:2003kb}; see also \citealp{Weingartner:2001eb}; \S\ref{sec:reflex_dust1}), while that of \textsc{tbabs} assumes grains with a size distribution following a power law with an index of $-3.5$ in the $0.025-0.25\mu$m size range \citep{Mathis:1977gx,Draine:1984ak}. Our choice to use the grain size distribution of \citet{Weingartner:2001eb} is due to the fact that their model is consistent with several different observables, such as i) the infrared emission from interstellar dust (e.g., \citealp{Li:2001ka}), ii) X-ray scattering halos  (e.g., \citealp{Rolf:1983rr}), and iii) optical and UV scattered light (e.g., \citealp{Draine:2003vd}).

\begin{figure}
\centering
\includegraphics[width=0.49\textwidth]{All_depletion_5e22_slab.ps}
\includegraphics[width=0.49\textwidth]{All_depletion_1e24_slab.ps}
\includegraphics[width=0.49\textwidth]{All_depletion_1e24_torus_edgeon.ps}
\caption{Ratio between the flux of fluorescence lines for \textsc{RefleX} simulations of dusty and non-dusty gas for different dust depletions, geometries and inclination angles. Fluorescence lines from some of the elements contained in the dust grains implemented in the latest version of \textsc{RefleX} are shown: oxygen ($0.525$\,keV), magnesium (1.25\,keV), silicon (1.74\,keV) and iron ($6.391$\,keV and $6.404$\,keV). Only photons that underwent at least a fluorescence were selected. {\it Top panel:} simulations for a slab with a vertical (i.e. along the shorter side) column density of $N_{\rm H}=5\times10^{22}\rm\,cm^{-2}$ observed at an inclination angle of $30^{\circ}$ with respect to the normal to the slab. {\it Middle panel:} same as the top panel for $N_{\rm H}=10^{24}\rm\,cm^{-2}$. {\it Bottom panel:} ratio between the flux of Fe produced in dusty and non-dusty gas for different values of dust depletion, assuming a torus with a column density $N_{\rm H}=10^{24}\rm\,cm^{-2}$ observed edge-on ($80^{\circ}$).}
\label{fig:fluorescentlines}
\end{figure}

\begin{figure}
\centering
\includegraphics[width=0.49\textwidth]{Plot_85d_zoomFe.ps}
\includegraphics[width=0.49\textwidth]{Plot_85d_zoomFeEdge.ps}
\caption{\textsc{RefleX} simulations around the Fe\,K$\alpha$ line and its Compton shoulder ($6.0-6.5$\,keV; top panel), and around the Fe\,K edge ($7.0-7.2$\,keV; bottom panel) for four different dust depletions assuming a torus geometry with a column density of $10^{24}\rm\,cm^{-2}$ observed edge-on ($85-90^{\circ}$), and considering a spectral resolution of 5\,eV.}
\label{fig:IronKregion}
\end{figure}

\section{X-ray emission and dusty gas}\label{sect:Xraydusty}

\subsection{The effect of dust on fluorescence lines}\label{sec:fluorescent}

We examine here the effect of dust on some fluorescence lines that are typically observed in astrophysical sources. We focus on lines that are produced by elements found in the dust grains we considered: oxygen ($0.525$\,keV), magnesium (1.25\,keV), silicon (1.74\,keV) and iron ($6.391$\,keV and $6.404$\,keV). We started by assuming a simple scenario with a point-like X-ray source located at $10^{17}\rm cm$ from a slab with a length of $2\times 10^{25}$\rm cm and a width of $10^3$\,cm. This configuration is used to reproduce a situation in which the X-ray source is located close to an extended cloud of dusty gas, and is similar to that assumed in the \textsc{pexrav} model \citep{Magdziarz:1995ic} that has been widely used for active galactic nuclei (AGN). We considered two different densities of the slab ($5\times10^{19}\rm\,cm^{-3}$ and $10^{21}\rm\,cm^{-3}$), which resulted into vertical column densities of the disk (i.e., along its shorter side) of $5\times 10^{22}\rm\,cm^{-2}$ and $10^{24}\rm\,cm^{-2}$, respectively. The X-ray continuum was generated to have a power-law spectrum with $\Gamma=1.8$ and a cutoff energy of 200\,keV (\textsc{cutoff} in \textsc{RefleX} ), consistent with the typical spectrum of nearby AGN (e.g., \citealp{Winter:2009iq,Ricci:2017if,Ricci:2018mp,Balokovic:2020fc}). We considered only photons that underwent at least one fluorescence event in the simulations, selected those observed with an inclination angle of $30-35^{\circ}$ with respect to the normal to the slab, and integrated the flux around the emission lines. In the case of the Fe\,K$\alpha$ photons we integrated in the range between 6.38 and 6.41\,keV to exclude photons that are down-scattered from the Fe\,K$\alpha$ doublet into the Compton shoulder. In all simulations we used the abundance table of \citeauthor{Wilms:2000vn} (\citeyear{Wilms:2000vn}; \textsc{wilm} in \textsc{RefleX}). The results are shown in the top and middle panels of Fig.\,\ref{fig:fluorescentlines}, and highlight the small effect of dust on the flux of the fluorescence lines, with the difference with respect to the dust-free simulations being at most $\sim 5\%$. In particular, the difference is $\lesssim 1\%$  for iron and oxygen.

We also tested a different scenario, in which the X-ray source is surrounded by a torus with an equatorial column density of $N_{\rm H}=10^{24}\rm\,cm^{-2}$, a covering factor of 0.7 and observed edge-on. This was done collecting photons in the $80-85^{\circ}$ range, and applying the same selection criteria we used for the slab, collecting both absorbed and reflected X-ray photons. The results are shown for the Fe\,K$\alpha$ line in the bottom panel of Fig.\,\ref{fig:fluorescentlines}.
In Fig.\,\ref{fig:IronKregion} we illustrate the X-ray spectra around the Fe\,K$\alpha$ line (top panel) and Fe\,K edge (bottom panel) for different values of the \textsc{dust} parameter. No clear difference is observed in the Fe\,K$\alpha$ doublet, nor in its Compton shoulder. On the other hand, a clear difference between the X-ray emission produced in dusty and dust-free gas is found around the Fe\,K edge, due to the strong effect of the NEXAFS (see \S\ref{sec:reflex_dust2}). As expected, the difference increases with the dust depletion, since more iron atoms are found in dust.

\begin{figure}
\centering
\includegraphics[width=0.43\textwidth]{Plot_0d_ratio_1_10_torhollow.ps}
\includegraphics[width=0.43\textwidth]{Plot_60d_ratio_1_10_torhollow.ps}
\includegraphics[width=0.43\textwidth]{Plot_85d_ratio_1_10_torhollow.ps}
\includegraphics[width=0.43\textwidth]{Plot_85d_ratio_1_10_sphere.ps}
\caption{Ratio between our \textsc{RefleX} simulations with and without dust, for different dust depletions: 0.5 (green dot-dot-dashed lines) and 0.7 (red continuous lines). The spectral resolution was set to 20\,eV. The geometrical setup of these simulations includes a torus plus a hollow cone (top three panels) and a sphere (bottom panel). For the torus plus hollow cone geometry the spectra were obtained considering different inclinations: pole-one ($0-5^{\circ}$), intermediate ($60-65^{\circ}$) and edge-on ($85-90^{\circ}$). For the spherical geometry the photons were also selected considering an angle of $5^{\circ}$. The simulations with \textsc{dust 1} were shifted by 80\,eV for visual clarity.}
\label{fig:ratiosmodels}
\end{figure}

\clearpage

\subsection{Comparison with spectroscopical simulations ignoring dust}\label{sect:simulations}

Here we examine the effect on the broad-band X-ray spectra of astrophysical sources of considering or not dusty gas, by simulating complex geometries with \textsc{RefleX}. We explored a few different geometries that are very relevant to AGN, but our results can be extended to any type of source of X-ray radiation. In the simulations we considered the same parameters for the X-ray continuum (i.e., photon index and high-energy cutoff) reported in \S\ref{sec:fluorescent}, and a molecular fraction of $f_{\rm H2}=20\%$. We tested also larger values of the molecular fraction ($f_{\rm H2}=80\%$; \citealp{Willingale:2013fm}) and found that this has only a marginal effect on our simulations. We started by considering a geometry that includes a torus and a hollow cone, i.e. the dusty components used by \cite{Andonie:2022rs} for the ad-hoc X-ray spectral model built with \textsc{RefleX}\ for the AGN in the Circinus Galaxy, based on high-resolution mid-IR observations \citep{Stalevski:2017fr,Stalevski:2019ej}. The column density of the torus was set to $1.5\times10^{24}\rm\,cm^{-2}$, while the covering factor to 70\%, consistent with what is typically found in local AGN (e.g., \citealp{Burlon:2011yn,Ricci:2015fk,Ricci:2017if}). The hollow cone extends from 0.1 to 40\,pc, and has a maximum column density of $3\times 10^{22}\rm\,cm^{-2}$. The ratios between simulations performed assuming this geometry and considering dusty and non-dusty gas are shown in Fig.\,\ref{fig:ratiosmodels} for different inclination angles and dust depletions. For unobscured lines-of-sight (top panel), the simulations produce consistent results for dusty and non-dusty gas. A clear difference emerges for obscured lines-of-sight (middle panels), particularly around the Fe\,K edge, and it increases with the line-of-sight $N_{\rm H}$. For the most obscured and inclined scenarios the ratio between the X-ray spectra of dusty and non-dusty gas shows a dip at $\sim 60\%$ and an excess of up to $\sim 10\%$.

We also explored a different scenario, in which an X-ray source is surrounded by a dense sphere of dusty gas. Such a situation can be found at the center of Luminous and Ultra-luminous IR galaxies (U/LIRGs), where accreting SMBHs are typically completely embedded in a large amount of dusty gas (e.g., \citealp{Koss:2016zl,Ricci:2017aa,Ricci:2021wb,Yamada:2021vk}), and possibly in Compact Nuclei (e.g., \citealp{Aalto:2015ni,Aalto:2019yr,Falstad:2021wf}). We considered that the material is distributed homogeneously in a sphere with a radius of $10^{17}\rm\,cm$ and a density of $1.5\times 10^{7}\rm\,cm^{-3}$, which results in a column density of $1.5\times 10^{24}\rm\,cm^{-2}$. We selected photons in an interval of $5^{\circ}$ and the results are illustrated in the bottom panel of Fig.\,\ref{fig:ratiosmodels}. The ratio shows the same features observed for the edge-on case of the torus plus hollow cone geometry.

\subsection{Dust scattering halos}\label{sec:dusthalo}
Dust grains strongly increase the scattering cross section of gas (see the top right panel of Fig.\,\ref{fig:ratio_crosssections}). The small-angle scatter of X-ray photons off dust in the ISM can produce diffuse emission around a X-ray source (e.g., \citealp{Overbeck:1965ow,Hayakawa:1970oy,Martin:1970nh,Martin:1970hk}). The first of such halos was detected by \cite{Rolf:1983rr} studying {\it Einstein Observatory} observations of GX339$-$4. Further observations, carried out with the {\it Einstein Observatory} detected scattering halos around several additional X-ray sources (e.g., \citealp{Catura:1983zu,Mauche:1986vs,Mauche:1989xp}). Following observations with {\it ROSAT} (e.g., \citealp{Predehl:1995ga}), {\it XMM-Newton} (e.g., \citealp{Costantini:2005bx,Tiengo:2010rx,Pintore:2017sk,Jin:2017mq}) and {\it Chandra} (e.g., \citealp{Tan:2004bs,Corrales:2015ew,Corrales:2017hm}) detected several more dust scattering halos around Galactic sources. Dust scattering was also recently observed around the brightest gamma-ray burst detected so far (GRB 221009A; \citealp{Tiengo:2022ul}).
In some variable X-ray sources, the interaction between X-ray photons produced in repeated bursts of radiation and the dust grains can give rise to scattering echoes, that can be observed as rings (e.g., \citealp{Corrales:2019pr,Lamer:2021no}). Such structures have been found around variable Galactic sources (e.g., \citealp{Heinz:2015ms}). A rapid and strong decrease of the X-ray flux in AGN could give rise to ``ghost halos" \citep{Corrales:2015jy}, with the dust scattering halo becoming detectable in the X-rays. These halos typically contain few tens of percent of the X-ray flux at a few keV \citep{Predehl:1995ga}, and could be used to infer some fundamental properties of dust in the ISM (e.g., \citealp{Mauche:1986vs,Mathis:1991wa,Corrales:2015jy}).

\begin{figure}
\centering
\includegraphics[width=0.4\textwidth]{ImageE2.ps}
\includegraphics[width=0.4\textwidth]{ImageE5.ps}
\par\smallskip
\includegraphics[width=0.48\textwidth]{Plot_angles.ps}
\caption{Simulations of a dust scattering halo around an X-ray source. The simulations consider a mono-directional X-ray source and slab of dusty gas ($N_{\rm H}=10^{22}\rm\,cm^{-2}$; \textsc{dust 0.7}), and have a resolution of $0.54\arcsec$. The top and middle panel show images obtained in the 1--2\,keV and 5--10\,keV range, respectively. Only scattered photons were selected. The bottom panel shows the spectra extracted using different apertures centered on the source. The spectral simulation was set to 30\,eV.}
\label{fig:scatteringhalo}
\end{figure}

The imaging capabilities of \textsc{RefleX}\ allow the user to create images of dust scattering halos around astrophysical sources, and the comparison of \textsc{RefleX}\ simulated X-ray images with observations could be used to improve our understanding of the ISM responsible for the scattering halos (e.g., \citealp{Draine:2006qa,Xiang:2011qm}). While currently \textsc{RefleX}\ only considers one dust size distribution, it allows the user to set complex geometrical configurations of the dusty gas. As an example of the imaging capabilities of \textsc{RefleX}\, in the top and middle panel of Fig.\,\ref{fig:scatteringhalo} we show two images produced assuming a point-like X-ray source absorbed by a slab of dusty gas with a column density of $N_{\rm H}=10^{22}\rm\,cm^{-2}$, considering the abundances of \citet{Lodders:2009vs}, \textsc{dust 1} and a molecular fraction of $f_{\rm H2}=20\%$. The scattered photons were selected in the 1--2\,keV and 5--10\,keV range for the top and bottom panel, respectively. The figures show the scattering halos, that can extend to several hundreds arcseconds from the X-ray source, and the remarkable difference in the size of the scattering halos, which decreases with increasing energy. This is consistent with what expected, according to \cite{Draine:2003kb}, for $E\gtrsim 0.5$\,keV the median scattering angle can be approximated, for the \cite{Weingartner:2001eb} dust, by:
\begin{equation}\label{eq:scatteringangle}
\theta_{\rm s, 50}\sim 360\arcsec \left(\frac{\rm keV}{E}\right).
\end{equation}
Simulated images using the same configuration, but assuming a dust-free ISM, would show almost no scattered photon around the X-ray source. This is due to the smaller values of the Compton and Rayleigh cross-sections (see top right panel of Fig.\,\ref{fig:ratio_crosssections}), and to the fact that the angular distributions of Compton and Rayleigh scattering are more isotropic than that of Mie scattering. In the bottom panel of Fig.\,\ref{fig:scatteringhalo} we show the spectra obtained by extracting the flux using annuli centred on the X-ray source with different apertures. For the annuli with the smallest radii ($2-5''$ and $10-15''$, black dotted and blue dashed lines, respectively) the spectral shape is very similar to that of the X-ray source (grey continuous line). At larger radii instead the spectral shape starts to deviate from that of the X-ray continuum, becoming increasingly softer as the distance increases (green dot-dashed, red dot-dot-dashed and purple dashed lines for $50-60''$, $100-200''$ and $500-1000''$, respectively). The change in the spectral shape is due to the relation between the median scattering angle and the energy (Eq.\,\ref{eq:scatteringangle}), with softer photons being more easily scattered at larger angles. This softening of the dust-scattered radiation has been observed in X-ray binaries: for the giant dust ring found at $\sim 1^{\circ}$ from MAXI\,J1348$-$630, \cite{Lamer:2021no} inferred a much softer spectrum ($\Gamma \simeq 4$) with respect to that expected for the source during the high/soft state ($\Gamma\simeq 2$).

Thanks to its new functionalities, \textsc{RefleX} could be used to produce X-ray spectral models for a given aperture to fully reproduce the emission of astrophysical sources  (see \citealp{Corrales:2016bq,Smith:2016ad}). Moreover, \textsc{RefleX}\ could also be used to reproduce dust rings around variable X-ray sources, and to infer the spectral properties of the emission during the outbursts that give rise to the dust rings.

\subsection{RXTorusD: a dusty torus model}\label{sec:RXTorusD}

\subsubsection{The model}
With the first version of \textsc{RefleX}\ \citep{Paltani:2017fa} we released a spectral model to reproduce the X-ray emission of AGN, \textsc{RXTorus}, which considered reprocessed radiation produced in a torus with variable covering factor and column density. With this paper we release a new version of the model, \textsc{RXTorusD}, i.e. the first torus model which considers dusty gas. \textsc{RXTorusD} assumes a geometry similar to that of the widely-used \textsc{MYTorus} model, but allowing the covering factor to vary (left panel of Fig.\,\ref{fig:RXTorusDcartoon}), and including more physical processes and more realistic cross-sections (\S\ref{sect:differencesAGNmodels}) with respect to current X-ray models (e.g., \citealp{Murphy:2009ly,Balokovic:2018my,Tanimoto:2019ts}).

\begin{figure*}
\centering
\includegraphics[width=0.46\textwidth]{RXTorusD.ps}
\includegraphics[width=0.46\textwidth]{Plot_ALL_ratio_torus.ps}
\caption{{\it Left panel:} schematic representation of the \textsc{RXTorusD} model. The model assumes that the isotropic X-ray source (red star) is surrounded by a torus with a major axis $R$ and a minor axis $r$. The covering factor of this obscurer is given by the ratio between the two axis ($r/R$). The inclination angle $i$ is the angle between the observer and the normal to the plane of the torus. Two column densities can be defined, the line-of-sight column density [$N_{\rm H}(i)$] (see Eq.\,\ref{eq:NHtor}) and the equatorial or maximum column density [$N_{\rm H}(\rm max)=N_{\rm H}(90^{\circ})$]. {\it Right panel:} ratio between the spectra of the \textsc{RXTorusD} model (for \textsc{dust 1}) and those obtained using the same geometry but considering the physical assumption of some of the most-commonly used torus model (i.e., ignoring dust, molecular gas and Rayleigh scattering). All simulations assume an equatorial column density of $N_{\rm H}(\rm max)=4\times10^{24}\rm\,cm^{-2}$, a covering factor of $70\%$ and two different inclination angles: $60-65^{\circ}$ (red continous line) and $85-90^{\circ}$ (black dot-dot-dashed line). The spectral resolution was set to 50\,eV.}
\label{fig:RXTorusDcartoon}
\end{figure*}

\textsc{RXTorusD} was generated by running a grid of simulations with varying parameters, generating $10^{10}$\,photons per simulations. We considered that the X-ray source is pointlike and emits isotropically. The primary X-ray continuum was assumed to have the form of a cutoff power-law, with the photon index $\Gamma$ varying between $1.0$ and $3.0$, while the cutoff energy was fixed to $E_{\rm C}=200$\,keV \citep{Ricci:2018mp}. The maximum energy of the photons was set to be 500\,keV (i.e., no photon was produced above this energy). The inclination angle between the observer and the normal to the plane of the torus ($i$) covers the range $0-90^{\circ}$, with a $3^{\circ}$ interval. Similarly to what was done for \textsc{RXTorus} \citep{Paltani:2017fa}, in order to consider the whole range of inclination angles we assumed that the first and last bin are be centred at 0$^{\circ}$ and 90$^{\circ}$, respectively. The equatorial column density of the torus, i.e. the maximum column density that can be observed for a given configuration [$N_{\rm H}(\mathrm{max})=N_{\rm H}(i=90^{\circ})$], covered the range $10^{22}-10^{25.5}\rm\,cm^{-2}$. The variable covering factor in the model is given by the varying ratio between the minor and major axis ($CF=r/R$), and varies between $0.01$ and $1$. For a given $r/R$ and $i$, the line-of-sight column density is given by
\begin{equation}\label{eq:NHtor}
\left\{\begin{array}{ll}
N_\mathrm{H}(i)=N_\mathrm{H}(\mathrm{max})\left( 1- \frac{R^2}{r^2}  \cos^{2} i \right)^{1/2} , &\cos i<\frac{r}{R},\\
N_\mathrm{H}(i)=0 , &\cos i>\frac{r}{R}\end{array}\right.,
\end{equation}
The gas in the torus was set to be neutral (\textsc{temperature 0} in \textsc{RefleX}), dusty and to have a molecular fraction of $f_{\rm H2}=20\%$ (\textsc{H2fraction 0.2}). We consider two dust depletions: \textsc{dust 0.5} and \textsc{dust 1} (i.e. the case in which iron is fully depleted). We used the proto-solar abundances from \cite{Lodders:2009vs} and assumed three different metallicities (0.3, 1=Solar, 2). The simulations were carried out using a resolution of 20\,eV in the 0.3--8\,keV range. Above 8\,keV, given the lack of narrow spectral features, we used a logarithmic step of $\Delta E/E = 0.001$.

In order to allow for flexibility, besides including a table that contains all simulations, the model is divided into different components: i) the transmitted continuum, containing only photons that did not undergo any interaction with the surrounding medium; ii) the scattered continuum, which includes all photons that underwent scattering, but neither photoionization nor fluorescence; iii) the fluorescence, which contains photons that underwent at least one photoionization and fluorescence event.  The free parameters of the model are the photon index ($\Gamma$) and normalization ($n$) of the primary X-ray emission, the covering factor ($r/R$) and equatorial column density [$N_{\rm H}(\rm max)$] of the torus, and the inclination angle between the observer and the normal to the plane of the torus ($i$).
Following this new release of \textsc{RefleX}, the other \textsc{RXTorus} models have been updated to include the proto-solar abundances of \citet{Lodders:2009vs} and to increase the number of photons per simulation.

\subsubsection{Improvements with respect to commonly-used AGN torus spectral models}\label{sect:differencesAGNmodels}

The main novelty of \textsc{RXTorusD} is that it considers a wide variety of physical processes, which make our simulations extremely realistic. None of the physical X-ray spectral models used to reproduce the emission of AGN currently considers dusty gas. Moreover, some of the most-commonly used models applied to the X-ray spectra of obscured AGN, such as \textsc{MYTorus} \citep{Murphy:2009ly}, \textsc{Borus} \citep{Balokovic:2018my}, \textsc{UxClumpy} \citep{Buchner:2019pf} assume that Compton scattering takes places on free electrons. This assumption is not realistic for cold reprocessing material, such as the circumnuclear dusty medium that surrounds AGN. Our simulations, on the other hand, consider the incoherent scattering functions of \cite{Hubbell1975}, which provide Z- and energy-dependent multiplicative terms to the Klein-Nishina cross-section. The result of these corrections is a reduction of the Compton cross section at low energies, which is more than compensated by the addition of Rayleigh scattering (see \citealp{Paltani:2017fa} for further details). Moreover, our simulations also consider coherent and incoherent scattering on molecular hydrogen. All this can result in large differences in the observed X-ray spectra, particularly below 10\,keV. This is clearly illustrated in the right panel of Fig.\,\ref{fig:RXTorusDcartoon}, which shows the ratio between two spectra from the \textsc{RXTorusD} model and two spectra obtained by considering the same geometrical and physical configuration but ignoring dust, molecular gas and Rayleigh scattering. For the simulations we assumed $N_{\rm H}(\rm max)=4\times10^{24}\rm\,cm^{-2}$, a covering factor of $r/R=0.7$, and considered two inclination angles: $60-65^{\circ}$ (red continous line) and $85-90^{\circ}$ (black dot-dot-dashed line).

\section{Summary and conclusions}

In this work we have reported on the implementation of dust in the ray-tracing platform \textsc{RefleX}\ \citep{Paltani:2017fa}. We have discussed how dusty gas is treated within our simulations, and how it is controlled by a single parameter, \textsc{dust}, which regulates the fraction of metals in dust grains (i.e. the dust depletion). We have discussed the different effects associated to the interaction between X-ray photons and dust grains, such as dust scattering, near-edge X-ray absorption fine structures and shielding (\S\ref{sec:reflex_dust2}), which are all included in \textsc{RefleX}. We have shown how the cross-sections of the photon-gas interaction change depending on the dust depletion factor (\S\ref{sec:crosssectionsdust} and Figs.\,\ref{fig:crosssections},\ref{fig:ratio_crosssections}). Our simulations were tested using some of the most-commonly used X-ray photoelectric absorption models, such as \textsc{phabs} and \textsc{tbabs} (\S\ref{sec:reflexvstbabs} and Fig.\,\ref{fig:phabs_tbabs}).
We have discussed the small effect of dust on the fluorescence lines (\S\ref{sec:fluorescent}, Fig.\,\ref{fig:fluorescentlines} and top panel of Fig.\,\ref{fig:IronKregion}), and showed the imprint left by the presence of dust on the X-ray spectra assuming different geometries (\S\ref{sect:simulations}), which is particularly important below 10\,keV and around the edges (bottom panel of Fig.\,\ref{fig:IronKregion} and Fig.\,\ref{fig:ratiosmodels}). We have shown how \textsc{RefleX}\ can be used to reproduce the X-ray dust scattering halos that are often observed around Galactic sources (\S\ref{sec:dusthalo} and Fig.\,\ref{fig:scatteringhalo}). In the future \textsc{RefleX}\ could be used to create spectral models for X-ray binaries considering different apertures, taking into account dust-scattered radiation.
Finally, we released a new X-ray spectral model (\textsc{RXTorusD}), which is the first torus model that considers dust absorption and scatter, and could be used reproduce the X-ray spectra of obscured active galactic nuclei (\S\ref{sec:RXTorusD}).  \textsc{RXTorusD} considers physical process that are not included in the most widely-used physical models, such as Rayleigh scattering and scattering on molecular gas, which can lead to strong differences in the predicted X-ray spectra for the same set of geometrical and physical parameters (right panel of Fig.\,\ref{fig:RXTorusDcartoon}). The realistic X-ray spectral models that can be created with \textsc{RefleX}\ will allow us to fully exploit the next-generation of X-ray facilities, in particular with the advent of the high spectral resolution instruments on-board {\it XRISM} (Resolve, \citealp{XRISM-Science-Team:2020fo}) and {\it Athena} (X-IFU, \citealp{Barret:2016ij}).

\begin{acknowledgments}

We thank Bruce Draine for his invaluable insights into the physics of dust. We thank the referee for their insightful feedback, which helped us to improve the quality and clarity of the paper.
CR acknowledges support from the Fondecyt Iniciacion grant 11190831 and ANID BASAL project FB210003.

\end{acknowledgments}

redpajama_set_name: RedPajamaArXiv


text:
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redpajama_set_name: RedPajamaGithub


text:
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To 25 liters of water at 50 °C we add 15 liters of water at a different temperature. How many °C should the water be colder than 50 °C so that 40 liters of the water obtained has a temperature 42.5 °C?
What is the weight of cast iron with a volume of 3575 cubic centimeters? The density of the cast iron is 7600 kg/m3
The ring made from gold and copper alloy has a weight of 14.5 g and a volume of 1.03 cm³. How much gold and how much copper it contains? The metal densities are Au 19.3 g/cm³ and Cu 8.94 kg·dm-3
Wood cuboid
What is the weight of the wood cuboid 15 cm, 20 cm, 3 m if 1 m³ wood weighs 800 kg?
The freezer has the shape of a cuboid with internal dimensions of 12 cm, 10 cm, 30 cm. A layer of ice of 23 mm thick was formed on the inner walls (and on the opening) of the freezer. How many liters of water will drain if we dispose the freezer?
Cork and swimming
If a person weighs 80 kg, how many kilograms of cork must take a swimming belt to float on water? The density of the human body is 1050kg/m³ and cork 300kg/m³. (Instructions: Let the human body and cork on a mixture with a density of 1000kg/m³. When you m
Aluminum wire of 3 mm diameter has a total weight of 1909 kg and a density of 2700 kg/m³. How long is the wire bundle?

redpajama_set_name: RedPajamaCommonCrawl


text:
Home > Delicious drives in the Netherlands: Arnhem to Utrecht, via the Veluwe
Delicious drives in the Netherlands: Arnhem to Utrecht, via the Veluwe
By Milou van Roon on May 28, 2017 in Attractions, Europe, Featured, Food and Drink, Going Out, Netherlands, Regions, Restaurants, Road Travel, Speciality Travel, Travel Miscellany, Western Europe
The last day of my Hertz adventure has arrived and that means it's time to stay a little closer to home, so I can return the car before closing time. The weather is spectacular today (29 degrees and sun), so I decide to head east into the countryside, away from the hordes of tourists that will inevitably take up the coastline. I decide to explore the combination of city and countryside, and when I'm in the area, I have to get my hands on the local classic of Arnhemse Meisjes.
Despite not visiting that often, Arnhem is one of my favourite Dutch cities. That's not due to its looks, because it's not nearly as impressive as Amsterdam, Utrecht or even Den Bosch. But Arnhem's got a great vibe. It's bustling and upcoming. In some ways it reminds me of urban Rotterdam, but with better nature surrounding it.
Our first Arnhem-stop was foodie related. We went looking for the real Arnhemse Meisjes: crispy flat cookies made of yeast dough, sprinkled with sugar. It might seem easy to find Arnhemse Meisjes, but I'm sad to say – you'd be cheating. There's only one bakery that makes the traditional cookies with yeast dough, and that is Banketbakkerij (Confectionary) Van Asselt.
The original cookies were first made in 1829, not by this bakery, but Van Asselt has been making them and getting famous for them for many decades. The recipe of the cookies (still handmade every week) has been featured in Roald Dahl's Revolting Recipe Cookbook. The writer fell in love with the cookies when first tasting them when he was in town for a book signing. Fast forward a few years and countless boxes of cookies that were shipped to the UK, and he asked to feature the recipe in the book.
I obviously had to taste them: they were delicious, and very addictive. The lady who works in the confectionary loves sharing the story of the bakery with her customers, as well as giving us many tips for places to eat in Arnhem.
After our sugar fix it was time to explore Arnhem. Don't miss one of the more recognizable buildings: the Musis Sacrum, a concert hall. The building always reminds me of Paris or Budapest. Other than that, the Duivelshuis is worth a visit. If you enjoy churches, the Eusebius church comes recommended, as you can take the elevator to the top from where you have an amazing view over the city.
Above everything I just really enjoy the atmosphere in Arnhem. It's full of original stores with fun home accessories, local clothing brands, and some funky cafes and restaurants. I could see myself living here. The area called Modekwartier is my favourite bit. We had lunch there at Caspar, in the sunshine. We opted for an amazing chickpea burger with goat's cheese and salsa, and a BLT on cornbread with creamy mayonnaise.
Time to escape the big city and head north of Arnhem, to the Veluwe area to find peace and quiet. We haven't actually been in the Veluwe, but we did drive around the area. The route from Arnhem to Otterlo was amazing, and from there we drove via Hoenderloo to Uchelen and via Kootwijk back to Utrecht. With regular stops to appreciate nature of course. Being in such a natural area with only small towns, a car rental comes in handy, so you can stop to take pictures whenever you please. I was grateful to have my Opel Mokka Turbo to explore!
After this it was time to return to Utrecht, where I returned the car.
Mostly I'm just happy I got to spend three sunny days exploring amazing places and eating delicious food in The Netherlands. The accompanying freedom was bliss… I also really liked Hertz's Opel Mokka Turbo car. Fancy, modern and sparing no luxury. The service was high class too. In three days I got to taste the best of Noord-Brabant, Zeeland and de Veluwe. Now only one question remains:
What is your favourite place to go on a road trip in the Netherlands?
Disclosure: This post is sponsored by Hertz.
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Ramkumar Yaragarla says:
Hi, When reading this post, felt like I was actually traveling through Netherlands. Good travel writing. I liked the pictures as well.
I like long distance driving. Never done the European circuit trip. Would you be writing about Australia trips as well.
Nice reading. Liked reading through your posts.
Ramkumar.
Mike Avola says:
I love this adventure of traveling with you! I love the way you make us feel, like a part of your trip. Great post!
Reshma says:
Arnhem looks like a fabulous place. The tale behind the cookies is interesting too! I must say that you were able to explore many places in a short time. Of course, the weather plays a great role!
Jeanne Cillie says:
Oh, what a beautiful tour, rather 3 tours, I had with you. We plan to tour the rural Netherlands next year , for 10 days only, by camper. This was a very nice appetiser!Thank you.


Demolition City Saints 'Lords Of The Wasteland' – Demon Doll Records Inc.
Every once and a while we come across a band we love but may not fit exactly into the Sleaze or Hair Metal genres. This female fronted band definitely rocks hard and should not be overlooked as one of the better releases of 2018! Imagine the the Go Go's on steroids (if you dare) - get a copy while supplies last. This is not a Demon Doll Release, so we do not have our usual large quantities.
This CD is silver pressed, officially licensed from the band and available for a limited time @ Demon Doll Records.
"Demolition City Saints have recently unleashed their debut album, Lords Of The Wasteland, onto the world, and it's currently one of the best surprises of 2018. I hadn't heard of them until a few days ago, and now I'm completely hooked."
"t's a superb, filler-free debut that's easily enjoyed in its entirety"
"Arguably the song on this record which is the most likely to be a hit and gatecrash the mainstream is "Go Baby Go", with its Glam Rock stomp and extremely catchy chorus. It's like Blondie, Garbage, and Joan Jett all rolled into one!"
"Waiting For You takes the band into a slightly more 'Classic Rock' direction with some huge, effect-soaked guitar riffs."
"Demolition City Saints etch out a nice musical landscape all their own with the vocal attack of Melody Black and Baby Strange. Their crystal clear vocals and undeniably pop-infused hooks sink deep within you. Along with the fierce, metal guitars and punk attitude, the vocal approach plays perfectly as an undeniable nod reminiscent of Blondie"
"If you are in the mood for something that will make you throw up the devil horns, bang your head but move you and leave you chanting along, there is no doubt this is the album for you."
"'Go Baby Go' comes next and is one of my high lights on the record. The bubblegum pop chorus recalling songs from the past with the classic rock n roll verses putting the emphasis on the great vocals...The catchiness reminds me a bit of something the Runaways would have crafted, and, if you don't find yourself randomly singing this to yourself throughout the day, you are a stronger person than me. 'Systematic Way' again brings the Go-Go's to mind with the vocal melodies at times reminding me of their old song 'Vacation'... The powerful 'Waiting for You' roars out of the speakers and should be a huge hit."


Blaxhall Art Group is an informal group who meet in Blaxhall Village Hall on Thursday mornings to enjoy the companionship of painting and drawing together.
Its members work on their own individual projects and at any one time you will find them working in watercolour, oil, acrylic, pastel or whatever has grabbed their interest!
Occasionally a visiting artist is invited to conduct a workshop or demonstration for the group.
Every year the group has the opportunity to show its work in the Blaxhall Art Exhibition which is held towards the end of June and is open to all local artists both amateur and professional.
This year the group has decided also to take advantage of the exhibition space in Woodbridge library to share its art with library visitors.
Its hopes you enjoy it!


The historic Royal National Park is the perfect bolt hole on a sunny day, with its stunning ocean front (there are miles of pristine surfing beaches to the north), cliff-top walks, river meadows and heathland. There are well-marked walking trails, picnic spots, Aboriginal rock drawings and plenty of opportunities for sports - from football to fishing.
Sydney's iconic beach resorts are where the city comes to escape from the rat race for the afternoon. Bondi, Manly, Balmoral - they all have their unique charms: Victorian bathing pavilions, achingly cool bars, surf-shacks and boutiques. They're self-contained mini townships by the sea, and well worth exploring. And the sand's great too!
Head to the native scrubland of Bradley's head, where you'll find picture-perfect beaches, home to the intriguing Eastern Water Dragons, a large, harmless lizard, most often to be found lazing in the sun!
Parramatta was the second British settlement in Australia, founded in 1788 and was originally known as Rose Hill. Here you'll find Australia's oldest public building, Old Government House, a handsomely pro-colonial Georgian villa dating from 1790. The restored Elizabeth Farm House and St Patrick's Cathedral all add a rare sense of history to the city's suburbs. There's good shopping and restaurants here, too.
Whale watching cruises from Darling Harbour or Circular Quay set out to spot whales as they migrate along the rim of the Pacific Ocean. While the Australian Reptile Park, an hour north of the city, offers a land-based natural excursion, and is home to kangaroos, wallabies, dingos and possums.
Further afield still, the stunning Blue Mountains offer outdoor sports, hiking - such as the accessible ridges of the Katoomba region - and cave exploration at Jenolan.
The Hunter Valley wineries are superb, with excellent visitor facilities, tastings and tours, while the friendly, small-scale city of Wollongong is a family friendly place, with model train rides, a smashing beach and scattering of thrilling water-sports.


Have you ever thought about the things that are involved in getting ahead of your problems and situations in terms of opening your business? Maybe you're opening a restaurant and you want to be sure that you're doing everything possible to stick to the plan and see what is going to work out the best, no matter what may come your way or how you will move forward with the things that you want to accomplish in the meantime?
Getting your liquor license in Texas does not have to be stressful. The fact of the matter is, there are a lot of things that you may be dealing with to get this to work and to make sure that you have done what you can in order to stick to your plans. Knowing what is going to happen in terms of the licensing and feeling good about how you may want to do it isn't only useful, but it can give you a solid handle on what it is that you want to be able to get done in the meantime and as you move into the future as well.
You can do your research and be sure that you're looking at all of the details that matter in these situations. You have a lot that you can do and, as you work out what is necessary, you'll find that there are a lot of different ways in which you may be trying to get things done. Take some time to look at what it is that you need to do and how you may want to try and achieve the goals that you have in mind. If you have everything in order, it'll be a lot easier for you when all is said and done, as well.


Ready for a change? Treat your home interior to an upgrade with some brand new furniture pieces from Hildretd Dept Store in East Hampton, NY. For the homiest of homes, add some warmth with goodies like rugs, throw pillows, and vases.
Hildretd Dept Store in East Hampton is ready to help. If you're looking for some well-crafted tile to freshen up your bathroom or kitchen, you've come to the right place. This spot has an excellent variety of colors and textures to choose from. Let the design experts at Hildretd Dept Store help you create the perfect look and layout for your home. Lay down a great new floor in your home with some help from their flooring specialists. Hildretd Dept Store is a dog-friendly establishment, so bring your pup along.
Groupon has verified that the customer actually visited Hildreth's Home East.


Great Car, it's PRE-OWNED... With NO ENGINE PROBLEMS... It has A/C, Heater, just needs freon, and it has Current Tag... Drives SMOOTH, FAST, and SAVES gas... It literally SAVES you TONS of Money on gas... This ENTIRE Offer / Car Includes ALL THIS FOR FREE: - 2 Texas License Plates - Original 08 Chrysler Radio RADIO INCLUDES: Cassette Player Volume Knob Seek Button Tune Button Scan Button AM and FM Radio Digital Time Display CAR ALSO INCLUDES 2 Windshield Wipers 3 Rearview Mirrors 2 Cup Holders 2 Doors 5 Seats 120 MPH Seat Belts Clean Title Clean Seats (w/ a few stains) Trunk Adjustable Seats Drives VERY FAST Runs VERY SMOOTH SAVES TONS OF GAS AND LOOKS VERY GOOD We DO NOT accept refunds, but we do ensure your satisfaction. We will ship the car for you, but only if the shipping cost is fully funded by the buyer, and of course, FREE pick-up is always the best. Thank you for your interest, and please leave a positive review of your experience with us. Hope you have a great day, and god bless you.


text:
package fr.pilato.spring.elasticsearch.it.xml.rest;

public class RestClientNamespaceTest extends AbstractXmlContextModel {
    private final String[] xmlBeans = {"models/rest/rest-client-namespace/rest-client-namespace-context.xml"};

    @Override
    String[] xmlBeans() {
        return xmlBeans;
    }
}


text:
Africa in Science
About UsOur Metrics
HomeAbout UsOur MetricsOur PublicationsOur VideosOur SponsorsOur SourcesOur TeamRepublish
Our vision is to create a data-driven, evidence-based mechanism that evaluates the quality of the scientific output of Africa-based institutes.
Africa in Science (AiS) is an online platform and Think Tank that tracks, analyses, visualises and evaluates the scientific research output of academic and research institutes in Africa. The aim is to uncover and bring to the fore under-researched and neglected topics in Africa, and to better understand how societal, economic and education sectors impact the scientific output and merit of research in Africa. Thus, generating an outlet that will ultimately stimulate the efficient allocation of resources and funding of science in Africa.
AiS Online: Our Africa-centric datahub and database serve as an open access knowledge hub that informs the world about science in Africa.
AiS ThinkTank: Our reports and reviews aim to understand and rationalise the impact of education, human development and socio-economic status on research in Africa.
AiS Community: AiS lectures and bitesize videos feature under-researched and neglected topics in Africa and promote knowledge and collaboration between scientists in Africa and its diaspora around the globe.
Download Our Brochure...
AiS In a Nutshell
We, at AiS, envisage research into issues that originate from and/or affect local populations should be led and conducted by regional academic and research institutes. In recent years, the number of scholarly articles published by African scientists has risen dramatically. However, the impact of education, economic and societal sectors on research output by Africa-based institutes has received little attention from a scientometric perspective. Our vision is to create a data-driven, evidence-based mechanism that tracks and evaluates the quality of the scientific output of Africa-based institutes, whilst taking into account the impact of education and socio-economic status and making the data accessible to researchers, organisations, governments, philanthropists, pharmaceutical companies, private investors and members of the public.
Such data has the potential to assist governments in transforming their countries, organisations to more efficiently direct their resources and members of the public to be better informed.
AiS exists to highlight the fast-growing yet seemingly overlooked scientific research output of Africa-based universities and institutes, using a plethora of country-specific indices.
Our goal is to :
Track the growth of African research through peer-reviewed scholarly articles authored by Africa-based researchers.
Raise local and global awareness of the rich scientific diversity across the continent.
Inform governments, non-profit funding bodies and members of the general public in Africa and around the globe about under-researched and neglected topics in Africa.
Assist governments, private and public organisations and/or philanthropists with efficient allocation of funding, subsidies and investment in science in Africa.
AiS engages with local communities in Africa to contribute to the continued growth of science in Africa by mentoring and providing apprenticeships to early-career professionals in the fields of scientometrics, bibliometrics, publishing, software development and cloud engineering.
AiS: The Africa-centric Datahub, Database and Cloud-Based Software
The website www.africainscience.org is a cloud-based, free-to-access platform that draws on the content of our Africa-centric database to:
Track the publication of peer-reviewed scientific articles by institutes in Africa.
Relate article information to educational and socio-economic indices including Gross Domestic products (GDP), population, literacy, gender parity, corruption and Human Development index.
Crystallise these into succinct graphics in a user friendly format. The platform aspires to serve as a knowledge hub that supports and informs stakeholders in African science.
AiS: The Think Tank
AiS ThinkTank utilizes our Africa-centric database and online hub to conduct data-driven, evidence-based research that aims to:
Understand better the link between research output and economic and societal impact.
Uncover the numbers behind scientific research progress in Africa.
Publish independent, multi-disciplinary scientific research reports, annual reviews and educational video lectures.
Share scientometric analysis that includes AiS's unique Africa-centric metrics with our community in and outside Africa.
Increase the visibility of scientific research of Africa-based universities and institutes.
improve strategies for the support of scientific research in Africa by local and international governments, not-for-profit organisations, pharmaceutical companies and private investors.
Aid efficient allocation of funding, subsidies and investment in science in Africa.
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text:
Q: Vagrant LoadError on OSX I am trying to install vagrant. After installation terminal command gives error.
Tried cleaning(docs link) and installing again.
I only install and try to run vagrant command from terminal.
This is what i get. I have no idea what it means.
/opt/vagrant/embedded/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:54:in `require': cannot load such file -- vagrant-share/helper/api (LoadError)
    from /opt/vagrant/embedded/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:54:in `require'
    from /opt/vagrant/embedded/gems/gems/vagrant-share-1.1.7/lib/vagrant-share/activate.rb:244:in `<encoded>'
    from /opt/vagrant/embedded/gems/gems/vagrant-share-1.1.7/lib/vagrant-share/activate.rb:16:in `RGLoader_load'
    from /opt/vagrant/embedded/gems/gems/vagrant-share-1.1.7/lib/vagrant-share/activate.rb:16:in `<top (required)>'
    from /opt/vagrant/embedded/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:54:in `require'
    from /opt/vagrant/embedded/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:54:in `require'
    from /opt/vagrant/embedded/gems/gems/vagrant-share-1.1.7/lib/vagrant-share.rb:23:in `block in <class:Plugin>'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.9.4/lib/vagrant/cli.rb:75:in `call'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.9.4/lib/vagrant/cli.rb:75:in `block (2 levels) in help'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.9.4/lib/vagrant/registry.rb:49:in `block in each'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.9.4/lib/vagrant/registry.rb:48:in `each'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.9.4/lib/vagrant/registry.rb:48:in `each'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.9.4/lib/vagrant/cli.rb:69:in `block in help'
    from /opt/vagrant/embedded/lib/ruby/2.2.0/optparse.rb:917:in `initialize'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.9.4/lib/vagrant/cli.rb:57:in `new'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.9.4/lib/vagrant/cli.rb:57:in `help'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.9.4/lib/vagrant/cli.rb:32:in `execute'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.9.4/lib/vagrant/environment.rb:308:in `cli'
    from /opt/vagrant/embedded/gems/gems/vagrant-1.9.4/bin/vagrant:127:in `<main>'

A: It seems to be an issue with your vagrant-share plugin (v. 1.1.7)
you can install latest version of the plugin
$ vagrant plugin install vagrant-share --plugin-version 1.1.8
Installing the 'vagrant-share --version '1.1.8'' plugin. This can take a few minutes...
Fetching: vagrant-share-1.1.8.gem (100%)
Installed the plugin 'vagrant-share (1.1.8)'!

and it should work after this

redpajama_set_name: RedPajamaStackExchange


On8/3.2016,We held the symposium for the community of the Fukuoka City Social Welfare Council.
First, our project members explained the overview of our Research Results about the Otagaisama Community.
Secondly, we had a Panel Discussion joined by residents and corporations.
we should how to build comfortable relationship between residents and corporations, by showing one of the examples of the community Café "Tamariba" in Kanayama district.
Through this project, they built a hang-out spot. At the community cafe, they soled local vegetable, goods, and had a cafe so locals could how somewhere to go, and here something to do.
Not only do the governments or corpolation five services, but also the residences can make the services themselves if they want.
Another example, was a supporting cooperative project with a private high school Tachibana highschool in Miawadai to understand the residents' activity for solving community issues in Miwadai district.
They established a cooperative program where stakeholders would volunteer helping the senior residents by washing cars, cleaning the neighborhood and cooking. Meanwhile the senior residence would teach the students in the life skills, like coretaking and communication, and job training.
The principal of Miadai and residential stakeholders are talking about the experiences of their project.
Also They talked about how residents and corporations should change their minds from "Privatization" to "Collaboration".
Beyond the differences stakeholders have about various activity principles, they should be looking for ways they can work together to explore possibility of cooperation.
That day was the first time we introduced our project to the residence of Fukuoka city.
Close to 100 peoplefrom the Fukuoka area participate in this symposium.
At the symposium We made a café like a "Café Tamariba" (hang out) in Kanayama school district in this venue in order to feel this concept of "A place where those with children as well as the elderly can casually get together".
We showed the key concepts for you to understand our project objects: Ogtagaisama Community.
(1) Extending the possibilities of solving the issues".
(2) Connecting people of different roles.
We hope that other groups will think about sustainable relationships and communities which are able to solve various issues.
Please use this email address for inquiries.
*When you send a message, please change the letter (a) to@.


text:
Q: Maintaining state of fragment or elements even when navigating away from the fragment I have a counterdown timer for my match time in a game that is within my match fragment;
//Countdown clock button
    Button counterBtn = (Button) view.findViewById(R.id.matchCountDownBtn);
    counterBtn.setOnClickListener(new View.OnClickListener()
    {
        @Override
        public void onClick(View v)
        {
            updateDBMatches("played", 1);
            final Button counterBtn = (Button) getView().findViewById(R.id.matchCountDownBtn);
            new CountDownTimer(20000, 1000){
                public void onTick(long millisUntilFinished){
                    stopWatch.setVisibility(View.VISIBLE);
                    counterBtn.setEnabled(false);
                    long l = millisUntilFinished / 1000;
                    int i = (int) l;
                    counterBtn.setText(secondsToString(i));
                }
                public  void onFinish(){
                    MediaPlayer mp = MediaPlayer.create(getContext(), R.raw.airhornsoundeffect);
                    mp.start();
                    //Disable score buttons
                    Button homeFoulsBtnDisabled = (Button) getView().findViewById(R.id.btnHomeFouls);
                    Button awayFoulsBtnDisabled = (Button) getView().findViewById(R.id.btnAwayFouls);
                    homeFoulsBtnDisabled.setEnabled(false);
                    awayFoulsBtnDisabled.setEnabled(false);
                    Button counterBtn = (Button) getView().findViewById(R.id.matchCountDownBtn);
                    stopWatch.setVisibility(View.INVISIBLE);
                    counterBtn.setText("FULL TIME");
                    updateDBMatches("played", 2);
                }
            }.start();
        }
    });

All works great, until someone navigates to another fragment and I get errors once the countdown has completed. So for example the MediaPlayer mp when it tries to play the sound throws a null exception.
Is there a way to maintain state of a fragment even if the user navigates to another one?
All help appreciated.


After urban Salisbury, Bradford is the smallest community in area, and consists of just the town itself, five adjoining parishes, and Limpley Stoke, which juts into former Somerset. It lies at the southern end of Wiltshire's limestone belt. Limestone, and modern imitations, are near universal in the area's buildings.
What distinguishes Bradford, and makes it so attractive, is its setting, perched on its hillside overlooking the river and its great bridge. Of its satellite villages - historically members of the greater Bradford - Winsley, Westwood, and Holt have considerable dormitory populations, while retaining (Holt especially) strong community identities of their own. South Wraxall, Monkton Farleigh, and Limpley Stoke are smaller and their populations more scattered.


text:
Medical Examiner releases names of 7 victims from Mokuleia plane crash
By Star-Advertiser Staff and Associated Press
LEILA FUJIMORI / LFUJIMORI@STARADVERTISER.COM
Investigators put up tarp along the fence line, Sunday, to cover the remains of a plane crash at Dillingham Air Field in Mokuleia. The Navy identified a 27-year-old sailor as one of 11 people killed in Friday's crash of an Oahu Parachute Center Beechcraft King Air at Dillingham Airfield.
Lt. Joshua Drablos
NICOLE ANAMA VIA AP
An undated photo provided by Nicole Anama shows Jordan Tehero.
UPDATE 3:30 p.m.:
The Honolulu Medical Examiner's Office today released the names of seven of the victims of Friday's skydiving plane that crashed at Dillingham Airfield, killing all 11 aboard.
Investigators from the National Transportation Safety Board are in town investigating the incident, which they called the deadliest civilian aircraft accident in the U.S. since a 2011 Reno Air Show crash that killed the pilot and 10 spectators. NTSB investigators said the plane apparently flipped and burned shortly after takeoff.
The names released today are:
>> Joshua Drablos, 27, U.S. military member stationed in Hawaii, Virginia resident
>> Nikolas Glebov, 28, St. Paul, Minnesota
>> Daniel Herndon, 35, Hawaii resident
>> Michael Martin, 32, Hawaii resident
>> Jordan Tehero, 23, Hawaii resident
>> Ashley Weikel, 26, Colorado Springs, Colorado
>> Bryan Weikel, 27, Colorado Springs, Colorado
Medical Examiner Dr. Christopher Happy and his staff plan to release the identities of the four remaining victims once they have been confirmed. There were 10 men and one woman among the victims.
Friends and family members earlier confirmed to the Honolulu Star-Advertiser that pilot Jerome Renck, Larry Lemaster and Casey Williamson, who along with Martin appeared to be employed by Oahu Parachute Center, were among the victims.
PREVIOUS COVERAGE
Bryan and Ashley Weikel
A Colorado Springs couple who were celebrating their first anniversary on Oahu were among the 11 killed in the crash, according to a Colorado newspaper.
The Colorado Springs Gazette reported today that it was the first skydiving adventure for Bryan and Ashley Weikel.
The newspaper reported that family members had not been officially notified as of this Monday morning but concluded that the couple was among the victims based on social media posts from Ashley Weikel, who had posted pictures of them boarding the skydiving plane on Friday.
Relatives told KCNC-TV the couple was excited to go skydiving, but Bryan's mother, Kathy Reed-Gerk, begged him not to go.
A makeshift memorial at Dillingham Airfield continues to grow today as mourners place flowers near the crash site where 11 people aboard a twin-engine plane were killed after the aircraft plummeted to the ground.
Investigators of the National Transportation Safety Board are the site continuing to examine the wreckage on the second day of their investigation.
The NTSB team will also look into aircraft maintenance records, runway and weather conditions as well as the pilot's logbook and training records.
The 11 people on board were on a plane operated by Oahu Parachute Center. Company representatives could not be reached for comment this morning.
The Beechcraft King Air 65-A90 crashed at the fence line shortly after takeoff Friday night. Investigators said the aircraft apparently flipped and burned shortly after takeoff.
Dillingham Airfield remains closed today because of the investigation.
The Navy identified a 27-year-old sailor as one of 11 people killed in Friday's crash of an Oahu Parachute Center Beechcraft King Air at Dillingham Airfield in Mokuleia.
Lt. Joshua Drablos was confirmed aboard the aircraft by the National Transportation Safety Board and confirmed dead by a local medical examiner, the Navy said today in a news release. Drablos was assigned to U.S. Fleet Cyber Command.
The Maryland man had been with the Kunia Cyber Mission Force since late 2018, except for a few months as a student at the Naval War College.
Drablos, who attended the Naval Academy, was on the Navy men's track and field team as a pole vaulter.
As a Jefferson Forest High School student, Drablos won the state title in pole vault in 2010, the year he graduated.
He was a track and field team captain and was president of the Teenage Republicans Club.
"Our thoughts and prayers go out to the family, friends, and shipmates of Lt. Joshua Drablos during this extremely difficult and painful time," said the commander of U.S. Fleet Cyber Command/U.S. 10th Fleet, Vice Adm. Timothy "T.J." White.
"Joshua was an invaluable member of the Fleet Cyber team, and we are deeply saddened by the loss of this humble warrior," White said.
Jordan Tehero
A budding videographer who fell in love with skydiving was one of the 11 victims of Friday's airplane crash in Mokuleia.
Jordan Tehero, 23, took up skydiving a few years ago as a distraction from the breakup of a relationship, his father, Garret, told The Associated Press. Then his son "went and fell in love" with the sport, he said.
The plane was carrying skydivers from the Oahu Parachute Co..
The Beechcraft twin-engine airplane that can seat 13 took off from the runway at Dillingham Airfield, banked and then inverted in the air and crashed near the airport's perimeter fence Friday evening, the National Transportation Safety Board member Jennifer Homendy said. There were no survivors.
Garret Tehero lives on Kauai, where his son also lived.
Tehero said he spoke with his son the morning of the crash. The two had flown to Honolulu together, the father for business and Jordan for skydiving. Jordan also worked as a security guard, and his employer wanted him to do some work in Honolulu on Sunday as well, so he decided to stay while his father went back to Kauai.
He said Jordan became interested in skydiving after he and a girlfriend broke up a few years ago.
"Sometimes people find a passion when they go through something, you know, that makes you want to take the mind off," the father said. "He went and fell in love with it."
Jordan's parents both expressed worries over his new hobby.
"Because of our fear, we wanted him to stop," the father said. "But he didn't have the fear that we had, so he just continued."
Any fears he may have had were taken care of with prayer. "He always told me, 'Dad, I pray before every flight, before every jump I pray,' " the father said.
Star-Advertiser reporters Allison Schaefers, Rosemarie Bernardo and William Cole, and the Associated Press contributed to this report.
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Before Zac Damon was ever in Screeching Weasel and Big in Japan, he was in Zoinks!, one of the greatest punk bands ever (if you ask me anyway). This album is a collection of Zoinks! songs that were on 7 inch's and compilations. The CD booklet explains where they came from in much more detail, and also gives listings of the labels you can get the original releases from, so I'm not gonna waste my time telling you about that. I will tell you that this CD contains two of my favorite punk songs ever. 'Stumble', which is a cover of a Man Dingo song, and 'Pedestal' are two classics. 'Stumble' has an unbelievably catchy chorus and guitar hook, while 'Pedestal' has one of the best guitar parts and some of the best drumming I've ever heard. By the way, Bob Conrad is one of the best technical drummers in punk rock, and Zoinks! are worth checking out for him alone.
There are 19 songs listed, but they add on about 4 or 5 more at the end of the CD. Most of the songs dont sound as good as the first 8, but that's understandible coming from old 7 inch's. And just cause they don't sound so hot doesn't make them bad. 'Carcinogen' and 'Yearbook' are two of the better songs on here, and they sound like tapes I make in my basement with a 20$ tape recorder. Anyway, this CD is a must have for any Zoinks! fan, and a good addition to the collection for any fan of punk rock. My non-punk friends think they sound like Green Day, and I can hear it a little bit, but Zoinks! are all together different from any band I've heard. They also have lots of 'Whoa's', which is a must for any good punk record, right?


text:
Q: How to embed php script in javascript? I want to know if I can include php scripts in javascript[1] the same way it can be done in html[2]
server.php:
<?php
    echo 'hello World';
?>

client.js (or client.php if necessary):
function foo() {
    var i = <?php include('server.php'); ?>
    console.log( i );
}

If it can be done, and if client.php must be used instead, I would really appreciate a minimal example with index.html/index.php as well, since I would like to see how I would include client now that it is a php file and not javascript

A: You can use output buffering to achieve something similar, although it's not possible to directly embed PHP code in JS.
Example:
server.php
<?php
    echo 'hello World';
?>

client.php - (.php extension enables the ability to parse PHP tags, but really outputs JS)
<?php
header("Content-type: application/x-javascript"); // Or 'text/javascript'
ob_start();
include( 'server.php');
$i = ob_get_contents();
ob_end_clean();
?>
function foo() {
    var i = '<?= json_encode( $i); ?>';
    console.log( i );
}

Edit:
If the server.php file will only return a simple string, then you can modify your code for client.php. Notice how I said "return" instead of output - If your server.php outputs anything, it will be sent to the browser as output (not what you want). Alternatively, you can set a variable in server.php which gets outputted in client.php, or encapsulate your code in a function:
server.php
<?php
function js_output()
{
    return 'hello world';
}
?>

client.php
<?php
header("Content-type: application/x-javascript"); // Or 'text/javascript'
?>
function foo() {
    var i = '<?php include( 'server.php'); echo addslashes( js_output()); ?>';
    console.log( i );
}

Note: You may also want to add a call to html_entities or htmlspecialchars.

A: It has to be a .php file. You need to set this as the first line in your client.php:
header("Content-type: text/javascript");

Then, you could create the file like that, and just include it, and use it as a regular javascript file. So with the

...

Update: example client.php file:
<?php
    header("Content-type: text/javascript"); // This bit must come first!
?>
var i = "<?php echo $somevar; ?>" // This is JavaScript code with some PHP embedded.

A: To embed PHP in a file the server needs to pass it through the PHP parser and it will only do that with files-types it has been told contain PHP markup, i.e. .php files. You could potentially tell the server to parse js-files as well, but I'm not sure if the mime-type would be set correctly. It would also require you to change the server settings. If you call the javascript-file .php the mime-type will definitely be wrong. The most compatible way to do this would be to put the javascript in the html-file (i.e. your .php file). If you want to keep the amount of javascript in your .php files to a minimum you can just put the variable-assignments in the .php file and keep the rest in your javascript file.
server.php:

The result is:

<?php
echo "My full name is $fname $lname.";
?>

*When you open test.php in a browser, you will get:
My full name is Jason Kent.

A: You cannot have a client load PHP. The only way you can do this is to have on server.php

Basically loading the javascript into the body of the page. Or alternatively.