text:
in Funding, Medical Countermeasures, Pathogens
CRADA Opportunity: Evaluating Influenza Countermeasures in Healthy Volunteer Challenge Model
by Global Biodefense September 26, 2017, 1:31 pm 8.9k Views
The high seasonal morbidity and mortality associated with both pandemic and seasonal influenza, the continued threat of highly pathogenic avian influenza infections, the development and global spread of antiviral resistance, and the need to plan for future influenza pandemics makes influenza a high priority in infectious disease research.
The National Institutes of Health (NIH) is announcing an opportunity for a Cooperative Research and Development Agreement (CRADA) for evaluating influenza vaccines and therapeutics in an Influenza A Healthy Volunteer Challenge Model developed at the National Institute of Allergy and Infectious Diseases (NIAID).
NIAID seeks to enter into a CRADA with one or more biotechnology or biomedical companies to use the Influenza A Healthy Volunteer Challenge Model developed for the purposes of developing new influenza drug treatments or vaccines.
NIAID's Influenza A Healthy Volunteer Challenge Model is using challenge viruses which are reverse genetics produced and cell cultured wild-type influenza A viruses for use in healthy volunteers under an Investigational New Drug (IND) application with the Food and Drug Administration (FDA). Currently NIAID has an A(H1N1)pdm09 Influenza virus available under an IND and plans to use its method of reverse genetics and cell culture to produce additional influenza strain preparations, including strain A/H3N2, for use in human studies.
Many important research questions about influenza infection and the resulting immune response can be approached through studies evaluating the impact of influenza vaccines and therapeutics on these aspects of influenza virology. For example, use of an influenza vaccine in NIAID's Influenza A Healthy Volunteer Challenge Model could further the understanding of what components of the anti-influenza immune response are important for protection against influenza infection. Use of a therapeutic in NIAID's Influenza A Healthy Volunteer Challenge Model could provide insights on viral titer and length of shedding and their relation to symptomatic illness, and the emergence of strains resistant to such therapeutics.
Depending on the nature of the vaccine or therapeutic being evaluated, broad scientific questions regarding influenza virology and immunology, not limited to the above examples, could be explored.
The first challenge virus, A(H1N1)pdm09, has been evaluated in the NIAID's Influenza A Healthy Volunteer Challenge Model and an optimal dose as well as methods of performing this type of study have been established. This validated model of infection in these volunteers will allow more efficient and cost-effective phase II clinical evaluation of antivirals and vaccines, as noted above, as well as an opportunity to study correlates of protection and the natural history and pathogenesis of influenza in a controlled setting. In NIAID's model, the timing of exposure will be known, a standard dose identified and used, and many other potentially confounding variables controlled for.
CRADA partners will be expected to have their own drug or vaccine well characterized, to have Phase I testing complete, and to have their drug or vaccine approved under an FDA IND prior to clinical studies beginning with the NIAID Influenza A Healthy Volunteer Challenge Model. CRADA partners should also have the capacity to recruit volunteers, to provide clinical facilities, and to provide the personnel required to conduct the research, all in coordination with the NIAID principal investigator. In addition, it will be expected that the collaborator would provide funding to supplement the NIAID principal investigator's laboratory budget to support this project.
Further details are available via Solicitation Number: NIAID-TTIPO-2012-002. The response deadline March 15, 2018.
InfluenzaNIAIDRequest for Proposals
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Dr. Ran Wei taught in Hong Kong prior to joining the faculty at the University of South Carolina. His research took him around the world, with a focus on Asian societies. Dr. Wei's research has won numerous awards, including the Best Article of the Year award in 2013 by International Marketing Review. He has written for Beijing News and has spoken frequently at media organizations.
Dr. Wei's interests focus on the processes of mass communication and effects of media messages in various contexts (political, social, promotional, health and risk) that involve a wide range of media channels and devices (traditional and emerging). Research that he has conducted includes media use and political participation, information-processing strategies and news learning effects, third-person effects of election polls and political attack ads, hostile media effect, uses and gratifications of new media, media messages as cultural values, media institutions and journalistic practices in Greater China.
Communication and Information, Nanyang Technological University, November 2007.
Principal Investigator, RPS (Research and Productive Scholarship) Grant ($4,820) for a project on "Avian Flu, Risk Perceptions and Information- seeking Behavior," awarded by The Office of Research and Health Sciences, University of South Carolina, 2006.
Co-Investigator, Special Grant for Hurricane Katrina for a project on "Communication Patterns and Knowledge Gap among Evacuees before and after Hurricane Katrina" ($24,980), awarded by the Office of Research and Health Sciences, University of South Carolina, October 2006.
Principal Investigator, National Advocacy Center Special Grant for a project on "Audience Viewing Behavior of the Justice Television Network" ($23,687), awarded by the National Advocacy Center, The U.S. Department of Justice, May 2005.
Dr. Wei's teaching interests include research design and methods (primarily quantitative) and SPSS/AMOS. He also teaches advertising and public relations (principles, research, campaigns, management, and international) and communication technologies, new media and society (theory, research methods, and mobile communication).
Wei, R., Lo, V., Xu, G., Chen, K., & Zhang, G. (forthcoming). Predicting mobile news use among college students: The role of press freedom in four Asian cities. New Media & Society.
Wei, R. (2014). Texting, tweeting, and talking: Effects of smartphone use on civic discourse engagement in China. Mobile Media & Communication. 2(1), 3-19.
Wei, R., & Lo, V. (2013). Perceived poll bias and inference of biased poll impact in the 2010 U.S. midterm elections: Media performance in the eyes of the beholder. The Open Communication Journal. 7, 1-9.


text:
""" Written by Timothy Hutz timothyhutz@gmail.com for inspecting github repos
the intention of this code is to be used with Lambda but can be customized with any
serverless architecture"""

import logging
logger=logging.getLogger()
logger.setLevel(logging.INFO)
import github

def main(event):
	reporesults = {}
	logger.info(event['repos'])
	try:
		git_session = github.Github(login_or_token=event['token'])
	except Exception as message:
		logger.error(message)
		exit(1)
	for repo in event['repos']:
		repobool = git_session.get_repo(full_name_or_id=repo).private
		reporesults[repo]=repobool
	return reporesults

redpajama_set_name: RedPajamaGithub


text:
En Línea es un informativo televisivo chileno, emitido por Telecanal Talca y antes en Telecanal. Se emitió de lunes a viernes a las 23:00, y fue presentado por el periodista Sergio Molleda Bohner, quien a la vez fue el productor y editor del informativo, así como también se desempeñó como Jefe del Departamento de Prensa de Telecanal.

Historia
El noticiero comenzó sus transmisiones al mismo tiempo que Telecanal, el lunes 5 de diciembre de 2005. Desde aquel momento y hasta el 14 de agosto de 2009, el logotipo y escenografía del noticiero presentaban un predominio de los tonos azules y verdes. Además, el noticiero poseía una duración máxima de 15 minutos y era emitido a las 21:45 (hora local).

En 2008 aumentó su duración a 30 minutos, a la vez que crecía el número de periodistas en el Departamento de Prensa del canal. El 17 de agosto de 2009, presentó una nueva imagen, caracterizada por el predominio de los colores blanco y naranjo. Junto a ello, estrenó una nueva escenografía.

La última edición del noticiero fue transmitida el viernes 22 de enero de 2010, debido al cierre del departamento de prensa del canal en febrero, sin embargo la sede regional de Telecanal en la Región del Maule sigue produciendo su versión de este informativo En Línea Maule hasta el día de hoy.

Referencias

Enlaces externos
En línea Maule de Telecanal Talca

Programas de televisión de Chile
Programas informativos de televisión de Chile
Programas de televisión de Telecanal
Programas de televisión iniciados en 2005
Programas de televisión finalizados en 2010
Televisión de Chile en 2005
Televisión de Chile en 2006
Televisión de Chile en 2007
Televisión de Chile en 2008
Televisión de Chile en 2009
Televisión de Chile en 2010

redpajama_set_name: RedPajamaWikipedia


text:
Los Angeles Lakers vs Houston Rockets Game 3 Predictions, Odds & Picks
Christian Jope - September 8, 2020
After losing Game 1, a concentrated effort from LeBron James and Anthony Davis brought the series level.
The Lakers only have three players averaging double-digit scoring.
Russell Westbrook has been awful shooting the ball, 35.9% from the field.
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Lakers vs Rockets Odds
Team Point Spread Total Money Line
Los Angeles Lakers -5 -108 O 225 -112 -205
Houston Rockets +5 -113 U 225 -109 +170
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Lakers vs Rockets Predictions and Picks
The Lakers continue to struggle with auxiliary contributions, but LeBron James and Anthony Davis look focused on not letting their team sink. On top of the fact that they've been unstoppable inside.
Picks:
Los Angeles Lakers def. Houston Rockets -205
Los Angeles -5 -108
Over 225 -112
How to Watch Lakers vs Rockets
Lakers vs Rockets Information
What Los Angeles Lakers vs Houston Rockets
Where ESPN Wide World of Sports, Orlando, FL
When Tuesday, September 8th, 2020; 9:00 PM EST
How to Watch/Listen TNT
Head-to-Head: Los Angeles Lakers vs Houston Rockets
Los Angeles Lakers Head-to-Head Houston Rockets
Frank Vogel Head Coach Mike D'Antoni
52-19 (1st in West, 3rd Overall) Standing 44-28 (4th in West, 8th Overall)
W-L-W-W Form L-W-W-W
112.0 (11th of 30) Off Rtg 112.0 (11th of 30)
106.3 (3rd of 30) Def Rtg 106.3 (3rd of 30)
100.9 (11th of 30) Pace 100.9 (11th of 30)
Playoff Leaders (Per Game)
A. Davis (29.7) PPG J. Harden (30.1)
A. Davis (10.1) RPG P. Tucker (8.2)
L. James (9.6) APG J. Harden (7.6)
R. Rondo (3.5) SPG R. Covington (2.4)
A. Davis (1.7) BPG R. Covington (1.4)
J. McGee (.708)/A. Davis (10.9) FG%/FGM R. Covington (.506)/J. Harden (9.3)
Q. Cook (.500)/L. James (2.3) 3P%/3PM R. Covington (.508)/J. Harden (3.6)
Los Angeles Has an Elite Defence
Many will look at the Los Angeles Lakers' last win against the Rockets with a positive light on Houston. The Rockets were able to score 72 points combined in the second and third quarter, but that did not discourage the Lakers at all.
Los Angeles has a collection of talented defenders, coordinated by one of the leagues best in Anthony Davis. Between the defensive threat of Davis, Rondo, Green, and Morris, the Lakers have the ability to shut down opponents on the perimeter and in the paint.
They held the Rockets to 20 points in the first quarter and 17 points in the fourth quarter. The California-based team can be elite when they want to be, but it will take a lot of effort against a high-octane Rockets team. The Lakers' defence will set the tone.
Houston Must Cross the Finish Line
The league's last Texas representative has a hard road ahead of them, facing off with one of the leagues best in the Los Angeles Lakers. While they went down against the Lakers early in Game 2, they were able to fight their way back from a 21-point deficit.
After going down 16 points in after the first half, the Rockets came out firing in the second half. Houston outscored the Lakers by 18 in the third quarter, powered by the performance of Eric Gordon. After shooting 68% in the third, the Rockets couldn't maintain their magic in the fourth.
It's no secret that they face a capable defence in the Lakers. But after losing the fourth quarter 17-27, the Rockets must sort out some defensive issues despite their offensive prowess.
Lakers Key Player: (G) Rajon Rondo
Outscored 'em by 28 when @RajonRondo was on the floor. #LakeShow pic.twitter.com/NxS5zgFro8
— Los Angeles Lakers (@Lakers) September 7, 2020
Many doubted the value of Rajon Rondo when he joined the Lakers. Despite being an NBA Champion and a multi-year All-Star, there were still concerns about his cohesiveness with a playmaker like LeBron James. In his two games back, he doubters have been silenced.
Rondo closed the evening in Game 2 as a team-high +28. He contributed 10 points and nine assists in just under 29 minutes of play. He also collected five steals on the evening, terrorizing the Rockets' guards on the perimeter.
Rondo will be crucial for the Lakers going forward. For the entire first round, the Lakers missed his playmaking off the bench. With his defence added to that, Los Angeles is a different team.
Rockets Key Player: (G) Russell Westbrook
TALK YOUR SHIT RUSS ? pic.twitter.com/Vx6nKtUJCG
— Top Ball Coverage (@TopBallCoverage) September 5, 2020
The 2017 NBA MVP has been struggling since his return to the court in the 2020 NBA Playoffs. In two games against the Los Angeles Lakers, Westbrook has disappointed.
Westbrook is still putting up numbers, averaging 17 points, 11 rebounds, and five assists in 32.5 minutes of play in the second round. The issue is that he is shooting just 35.9% from the field and a dreadful 16.7% from three-point range.
Westbrook plays best when he is going downhill, on the break or in the halfcourt. His three-point shooting has been a detriment to the Rockets with Harden as the primary playmaker, so Westbrook must find a way to make an impact efficiently.
Bet on Lakers to Win (-205)
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Evan Henningsen
Brooklyn Nets vs New York Knicks Predictions, Odds & Picks
Kevin Durant leads his ailing Brooklyn Nets against RJ Barrett and the high-energy New York Knicks! …
Christian Jope
Golden State Warriors vs Indiana Pacers Predictions, Odds & Picks
Stephen Curry and his Golden State Warriors look to carry their momentum forward against Domantas Sabonis' Indiana Pacers! …
Expert on NBA
Christian Jope is a writer, social media strategist, and data analyst. A Queen's University Alumni, Christian is an author and social media strategist with Raptors Cage, while also working closely with MLSE and Canada Basketball through community-driven events.

redpajama_set_name: RedPajamaCommonCrawl


text:
JUST A GIRL: BritFlicks Goes Behind The Scenes With Claudia Grace McKell.
JUST A GIRL is a film written and directed by Claudia Grace McKell,
JUST A GIRL is a film written and directed by Claudia Grace McKell, which highlights the difficulties a young adult has when she loses her hearing, as well as showcasing the pressures it has on family life. The film follows the story of a troubled, young, deaf woman and how her life shifts when she meets the local hero in a karate class.
The film also highlights the image of female fighters competitively and their struggle to compete in a sport dominated by men. It aims to showcase the ability of female fighters and promote the need for more encouragement to enhance and nurture female fighters professionally.
JUST A GIRL is the debut film from Essex Girl Productions
JUST A GIRL is the debut film from Essex Girl Productions, a production company encouraging women into film as writers, producers and directors. It aims to promote female led stories and female led productions.
www.facebook.com/JustAGirlFilm1
Please subscribe to the BritFlicks YouTube Channels.
BritFlicksExtra for behind the scenes
BritFlicks for the latest indie film trailers
Claudia Grace Mckell
Britflicks
BritFlicksExtra
Britflicks Extra interview
Britflicks Extra


text:
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text:
BAKING HACKS
Dairy Hacks: Best Sour Cream Substitute?
Cooking Hacks24 Jul, 2020
Sour cream is a popular dairy product typically used as a dip in sauces, salads, and baked goods.
Sour cream is produced by fermenting regular cream with lactic acid bacteria. With its creamy and tangy taste, many people like sour cream in their food, although some don't want or can't have it in their food for various reasons.
If you're looking for sour cream substitutes, here are a few equally delicious suggestions.
Sour Cream Substitutes
Greek Yogurt This is a common substitute for sour cream because it has the same consistency. Moreover, it has lower calories and fat and higher protein content, making it a healthier choice for the diet-conscious. Use the same amount of Greek yogurt in recipes as a replacement for sour cream.
Crème Fraiche Sounds fancy? While it may sound intimidating, crème fraiche is the same as regular cream, only with an additional ingredient: bacterial culture. Crème fraiche is slightly similar to sour cream in taste and texture.
Crème fraiche, however, is calorie-dense and may not be ideal for those who are watching their diet. To substitute in sour cream, use the same amount called for.
Buttermilk Buttermilk is tangy like sour cream but has a thinner consistency. It is a great substitute as far as flavor is concerned, and is recommended mainly in dressings and baked goods.
Heavy Cream and Lemon Juice Mixing a tablespoon of lemon juice with a cup of heavy cream creates a substitute that is somewhat closer in texture and taste to sour cream. Use it in recipes calling for sour cream in baked goods, dressings, and other sauces.
Heavy Cream, Yogurt, and Mayonnaise Like the others, this is also a fat and calorie-dense substitute, and may not be recommended for the diet-conscious. But take note that this is among the excellent sour cream substitutes you may come across. To prepare, blend an equal proportion of each: heavy cream, yogurt, and mayonnaise.
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Did you know that 70% of cats show signs of oral disease by just 3 years of age? If left untreated, dental disease can lead to unnecessary discomfort and pain, tooth loss, or damage to other body organs such as the liver and kidneys. The good news is that gum disease can be prevented with routine exams and at-home care.
Your cat's oral health is one of our top priorities at Cat Care Clinic, which is why we place a strong emphasis on our comprehensive dental services. At every physical exam, we examine your cat's mouth and teeth. If we detect any problems, such as tartar buildup, we schedule an appointment for complete dental treatment.
Cat Care Clinic's dental services are designed to keep your cat's teeth and gums healthy for a lifetime. In addition to our dental cleaning (scaling and polishing) services, we can extract teeth if necessary. We also rely on digital dental X-ray technology to view below the gum line, as this is where a large number of dental problems are found.
For your cat's safety, we perform all dental procedures under general anesthesia. We first perform a comprehensive exam and pre-anesthetic blood work to ensure that your cat is healthy enough for a dental procedure. We also offer extensive monitoring services to ensure your cat's safety before, during, and after their procedure.
Unsure if you should have your cat's teeth cleaned at Cat Care Clinic or another veterinary hospital? Read our Dental Comparison Chart for a full list of dental services we provide as compared to other clinics. If you have questions about how we price our dental treatment, view the following About the Dental Treatment Plan document.
On this page, you will also find information about a variety of other feline dental topics. Click on the headers below to learn more about them.
If any of these signs are noticed, we recommend that you schedule an appointment to have your cat examined.
Below is a list of some of the most common dental problems seen in cats—all of which we can treat here at Cat Care Clinic.
Feline Oral Resorptive Lesions (FORL): These lesions are very painful and can be only be treated by extracting the affected tooth. View our FORLs document to learn more.
Tartar and gingivitis: Tartar accumulates on your cat's teeth daily, but home care can help prevent build-up.
Fractured crowns: Fractured crowns are also very painful and can lead to infection (abscess). A fractured tooth is either extracted or repaired with root canal therapy by a board-certified veterinary dentist.
Tooth root abscess: Abscesses can occur from a fractured tooth or long-standing gum disease. Teeth with abscesses have to be extracted, and your cat will be placed on a course of antibiotics.
Caring for your cat's teeth from home can lower or even eliminate the risk of gum disease while also preventing tooth loss. It can also help freshen the breath and even prolong your cat's life. Although home dental care is easiest if you start when your cat is a kitten, an oral hygiene regimen can be started at any age. We'll be happy to perform a demonstration of effective brushing at your next visit.
Another important part of at-home dental care is choosing the right products. Here at Cat Care Clinic located in Ormond Beach, we carry several products for feline home dental hygiene, including C.E.T.® toothbrushes, toothpastes, chews, and Aquadent water additive. We also carry Hill's Prescription Diet t/d Feline®, which is specially formulated for feline dental health. For the best results, at least one of these products should be used daily.


text:
\section{Introduction}\label{sec:Introduction}

The possibility of kaon bound states in nuclei~\cite{PL7.288,Akaishi:2002bg} has been intensely discussed recently~\cite{Shevchenko:2006xy,Ikeda:2007nz,Shevchenko:2007zz,Yamazaki:2007cs,Dote:2008in,Dote:2008hw,Ikeda:2008ub,Ikeda:2010tk} and is one of the central subjects in forthcoming experiments at Japan Proton Accelerator Research Complex E15~\cite{Hiraiwa:2011zz}, FOPI at GSI~\cite{Suzuki:2009zze}, and AMADEUS at DA$\Phi$NE~\cite{Zmeskal:2010zz}. An important theoretical concept to describe kaonic nuclei is the two-body $\bar{K}N$-$\pi\Sigma$ interaction, which closely relates to the description of the $\Lambda(1405)$ resonance in the $I=0$ amplitude. Theoretical models of the $\bar{K}N$-$\pi\Sigma$ scattering amplitudes have been constrained by the total cross sections of low-energy $K^-p$ scattering into various final states and the threshold branching ratios of the $K^-p$ channel. Recently, due to intensive experimental activities, new data of the $\pi\Sigma$ invariant mass distributions are becoming available, and the analysis of the energy level and width of the kaonic hydrogen provides precise information regarding the $K^-p$ scattering length~\cite{Bazzi:2011zj}.

In this way, there are many experimental data around the $\bar{K}N$ threshold, while the amplitude at far below the threshold is not well constrained. This means that the $\bar{K}N$-$\pi\Sigma$ interaction relevant to the study of the $\bar{K}$-nucleus systems with strong binding is achieved only through the subthreshold extrapolation from the $\bar{K}N$ threshold. For instance, the chiral unitary model~\cite{Kaiser:1995eg,Oset:1998it,Oller:2000fj,Lutz:2001yb,Hyodo:2011ur}, a coupled-channels approach with the low-energy interaction constrained by chiral symmetry, has revealed an interesting two-pole structure~\cite{Jido:2003cb}. This indicates that the nominal $\Lambda(1405)$ resonance is not a single state but a superposition of two states with different properties. It is shown that this two-pole structure has substantial influence for the $\bar{K}N$ interaction~\cite{Hyodo:2007jq} and the $\bar{K}NN$-$\pi\Sigma N$ system~\cite{Ikeda:2010tk}. However, it is found that the position of the lower energy pole is sensitive to the details of the model, due to the lack of the information of the $\pi\Sigma$ interaction~\cite{Borasoy:2004kk,Borasoy:2005ie,Oller:2005ig,Oller:2006jw,Borasoy:2006sr,Ikeda:2011dx}.

The scattering length characterizes the property of the two-body interaction. The attractive/repulsive nature of the interaction is reflected in the sign of the scattering length. The magnitude is sensitive to the singularity of the amplitude close to the threshold. If there is a bound (virtual) state, the scattering length becomes large and negative (positive), as is known for the ${}^3S_1$ (${}^1S_0$) $NN$ scattering~\cite{BlattWeisskopf}. In the case of the $\bar{K}N$-$\pi\Sigma$ interaction, it is shown that the position of the lower energy pole of $\Lambda(1405)$ is closely related to the $\pi\Sigma$ scattering length with isospin $I=0$~\cite{Ikeda:2011dx}. Therefore, it is highly desirable to determine the $\pi\Sigma(I=0)$ scattering length to impose further constraints on the low-energy $\bar{K}N$-$\pi\Sigma$ interaction. There are several ways to extract the hadron scattering length in experiments. The standard method is to measure the energy shift and the width of the hadronic atom state~\cite{Beer:2005qi,Adeva:2005pg,Gasser:2007zt,Bazzi:2011zj} or to extrapolate the low-energy phase-shift data down to the threshold~\cite{Batley:2007zz}. Unfortunately, both methods cannot be applied to the $\pi\Sigma$ case.

Recently, an alternative method to determine hadron scattering lengths was proposed by Cabibbo~\cite{Cabibbo:2004gq,Cabibbo:2005ez}, in which the cusp effect at the $\pi^+\pi^-$ threshold is used to extract the $\pi\pi$ scattering length in the $K^+\to \pi^+\pi^0\pi^0$ decay. The structure around the cusp at the $\pi^{+}\pi^{-}$ threshold is related to the scattering amplitude of the $\pi^{+}\pi^{-}\to\pi^{0}\pi^{0}$ process, which is nothing but the $\pi\pi$ scattering length (the relationship between the scattering length and the cusp phenomena in the $\pi\pi$ spectrum has been discussed also in Ref.~\cite{Meissner:1997fa}). The cusp effect is indeed observed in the high-statistics experimental data~\cite{Batley:2005ax,Batley:2010fj} which leads to the determination of the $\pi\pi$ scattering length.

In this paper, we propose to apply a similar methodology to the $\pi\Sigma$ scattering lengths by use of the $\Lambda_c\to \pi\pi\Sigma$ decays. This decay process has been measured as the $\Lambda_{c}$ peak in the three-body invariant mass spectrum in Refs.~\cite{Barlag:1992jz,Kubota:1993pw,Avery:1993ri,Frabetti:1994kt,VazquezJauregui:2008eg}. The branching ratios to the relevant decay channels are reported as a few percents by the Particle Data Group (PDG)~\cite{Nakamura:2010zzi}, so the extraction would be feasible at Belle and Babar where a huge amount of $\Lambda_c$ is produced.

The contents of this paper are as follows. In Sec.~\ref{sec:analysis}, we discuss the general property of the threshold cusp phenomena in the $\Lambda_{c}\to \pi\pi\Sigma$ process. We introduce an expansion scheme to extract the scattering length, keeping the value of the scattering length unspecified. In Sec.~\ref{sec:estimation}, we present theoretical estimations of the decay process and show the expected spectra for several values of the scattering lengths. The last section is devoted to the summary.

\section{Analysis of the cusp phenomena}\label{sec:analysis}

Here we analyze the threshold cusp phenomena in the $\Lambda_c\to \pi\pi\Sigma$ decay. We review the general argument of the determination of the scattering length from the threshold cusp effect and summarize the possible $\pi\Sigma$ channels in the $\Lambda_c$ decay where we have a chance to observe the cusp structure. We then discuss the method to extract the scattering length with minimal model assumptions by expanding the amplitude in terms of the momentum variable. We also present an extension of the framework to the case with complex amplitudes.

\subsection{$\Lambda_c\to \pi\pi\Sigma$ decay and the $\pi\Sigma$ scattering length}\label{subsec:idea}

Let us consider the weak decay of $\Lambda_c$ into two pions and one $\Sigma$ baryon. We denote a $\pi\Sigma$ pair in the final state as $(\pi\Sigma)_l$ and concentrate on the threshold energy region of this pair. In this case, the additional primary pion has a large momentum because of the large phase space of the decay process, as we see in Appendix~\ref{sec:kinematics}. Choosing an appropriate charged state for the $(\pi\Sigma)_l$ pair, other charge combinations of the $\pi\Sigma$ state may be allowed at slightly higher energies than the $(\pi\Sigma)_l$ threshold due to the isospin violation in the particle masses. We denote the higher energy channel of the $\pi\Sigma$ pair as $(\pi\Sigma)_h$. The specific charge states of $(\pi\Sigma)_l$ and $(\pi\Sigma)_h$ will be given in Sec.~\ref{subsec:threshold}, in connection with possible experimental observations.

\begin{figure}[bp]
    \centering
    \includegraphics[width=0.45\textwidth,clip]{diagrams.eps}
    \caption{\label{fig:diagrams}
    Decay diagrams for the $\Lambda_c\to \pi(\pi\Sigma)_l$ process:
    (a) direct decay and
    (b) decay through the $(\pi\Sigma)_h$ state.
    Solid circles denote the weak process of $\Lambda_c\to \pi\pi \Sigma$
    and the open circle represents the scattering amplitude of the
    $(\pi\Sigma)_h\to (\pi\Sigma)_l$ process.}
\end{figure}%

The dominant part of the $\Lambda_c$ decay is given by the direct process:
\begin{align}
    \Lambda_c
    \to & \pi(\pi\Sigma)_l ,
    \nonumber
\end{align}
as shown in Fig.~\ref{fig:diagrams}(a). In addition, we may have the final-state interaction term with the intermediate $(\pi\Sigma)_h$ state as
\begin{align}
    \Lambda_c
    \to & \pi(\pi\Sigma)_h
    \to \pi(\pi\Sigma)_l,
    \nonumber
\end{align}
which is depicted in Fig.~\ref{fig:diagrams}(b). Because of the mass difference, the $(\pi\Sigma)_h$ threshold appears in the mass spectrum of the $(\pi\Sigma)_l$ channel slightly above the $(\pi\Sigma)_l$ threshold. The cusp phenomenon occurs at this higher energy threshold.

It is important to note that the amplitude in Fig.~\ref{fig:diagrams}(b) contains the vertex of $(\pi\Sigma)_h\to (\pi\Sigma)_l$. The threshold cusp takes place with the vanishing momentum of the $(\pi\Sigma)_h$ state, and it contains the information of the on-shell scattering amplitude of the $(\pi\Sigma)_h\to (\pi\Sigma)_l$ process. Following Ref.~\cite{Cabibbo:2005ez}, we define the off-diagonal $\pi\Sigma$ scattering length as (the real part of) the amplitude $f_{h\to l}$ at the higher energy threshold $W=W_{\text{th}}$:
\begin{align}
    a_{h\to l}
    \equiv &
    f_{h\to l}(W=W_{\text{th}})
    \label{eq:def} ,
\end{align}
which is reflected in the behavior of the cusp structure. In the following, we show how to extract the scattering length~\eqref{eq:def} along the same line with Ref.~\cite{Cabibbo:2004gq}.

\subsection{Possible decay modes for the scattering length}\label{subsec:threshold}

\begin{figure}[bp]
    \centering
    \includegraphics[width=0.4\textwidth,clip]{pSthreshold.eps}
    \caption{\label{fig:pSthreshold}
    (Color online)
    Threshold energies of the $\pi\Sigma$ states with charge $Q$. The arrows indicate the possible decay modes in which visible cusp structure may appear.}
\end{figure}%

We first consider the energy levels of the $\pi\Sigma$ channels with different charge combinations to specify the $(\pi\Sigma)_l$ and $(\pi\Sigma)_h$ channels. Since the charge $Q=\pm 2$ states have no coupled channels, they are not relevant in the present discussion. The threshold energy levels for the $Q=0$, $+1$, and $-1$ channels are shown in Fig.~\ref{fig:pSthreshold}. Unlike the $\pi\pi$ case where the masses of $\pi^+$ and $\pi^-$ are identical, $\Sigma^-$ is heavier than $\Sigma^+$, so the $\pi\Sigma$ channels show a rich spectrum. Among them, there are about 10-MeV mass differences in the following transitions:
\begin{align}
    \pi^{+}\Sigma^-
    \to &\pi^{-}\Sigma^+ ,
    \quad \pi^{+}\Sigma^-
    \to &\pi^{0}\Sigma^0 ,
    \quad \pi^{+}\Sigma^0
    \to &\pi^{0}\Sigma^+ .\nonumber
\end{align}
We expect to observe the cusp effects by regarding these decays as $(\pi\Sigma)_h\to (\pi\Sigma)_l$.

Using the isospin decomposition with the phase convention given in Eq.~\eqref{eq:phaseconvention}, we can express the scattering lengths in these channels as
\begin{align}
    a^{-+}
    = & \tfrac{1}{3}a^{0}
    -\tfrac{1}{2}a^{1}
    +\tfrac{1}{6}a^{2}+\dotsb  ,
    \nonumber \\*
    a^{00}
    =&\tfrac{1}{3}a^{0}
    -\tfrac{1}{3}a^{2}+\dotsb  ,
    \nonumber \\
    a^{0+}
    =&-\tfrac{1}{2}a^{1}
    +\tfrac{1}{2}a^{2}+\dotsb ,
    \nonumber
\end{align}
where the scattering lengths are labeled by the charges of the final states, $a^{I}$ is the scattering length with isospin $I$ in the isospin basis, and the ellipses represent the isospin breaking corrections.\footnote{In principle, $a^{1}$ can be complex, since the $\pi\Lambda$ channel is open at the $\pi\Sigma$ threshold. However, the transition $\pi\Sigma(I=1)\to \pi\Lambda$ vanishes at the leading order in chiral perturbation theory. In the following we assume the imaginary part is negligible.} Although we have three equations, they are not linearly independent if we neglect the isospin breaking corrections as
\begin{align}
    a^{-+} - a^{00}
    = &a^{0+} +\dotsb .
    \nonumber
\end{align}
Therefore, even if we extract $a^{-+}$, $a^{00}$, and $a^{0+}$  in experiments, in order to determine all three $a^{I}$s, we need one additional input. We may adopt chiral perturbation theory (ChPT) or the lattice QCD simulation for the determination of $a^{I=2}$ where the interaction is presumably weak and repulsive.

Let us check the decay modes of $\Lambda_c$ which lead to these rescattering amplitudes. Since the charge of $\Lambda_c$ is $Q=+1$, the possible decay modes are
\begin{align}
    a^{-+} :& \Lambda_c\to \pi^+(\pi^+\Sigma^-)
    \to \pi^+(\pi^-\Sigma^+) ,
    \label{eq:amp} \\
    a^{00} :& \Lambda_c\to \pi^+(\pi^+\Sigma^-)
    \to \pi^+(\pi^0\Sigma^0) ,
    \label{eq:a00} \\
    a^{0+} :& \Lambda_c\to \pi^0(\pi^+\Sigma^0)
    \to \pi^0(\pi^0\Sigma^+) .
    \label{eq:a0p}
\end{align}
For later convenience, we refer to these modes as the extracted scattering lengths, i.e., $\Lambda_c\to \pi^+(\pi^+\Sigma^-) \to \pi^+(\pi^-\Sigma^+)$ is called mode $a^{-+}$. The experimental data~\cite{Nakamura:2010zzi} of the branching ratios $\Gamma_i/\Gamma$ for these channels are summarized in Table~\ref{tbl:ratios}.

\begin{table}[tb]
\caption{\label{tbl:ratios} Decay branching ratios $\Gamma_i/\Gamma$ from PDG~\cite{Nakamura:2010zzi}.}
\begin{ruledtabular}
\begin{tabular}{lcc}
mode & $\Lambda_c\to \pi(\pi\Sigma)_h$ & $\Lambda_c\to \pi(\pi\Sigma)_l$ \\
\colrule
$a^{-+}$ & $1.7\pm 0.5$ \% & $3.6\pm 1.0$ \% \\
$a^{00}$ & $1.7\pm 0.5$ \% & $1.8\pm 0.8$ \% \\
$a^{0+}$ & $1.8\pm 0.8$ \% & Not known \\
\end{tabular}
\end{ruledtabular}
\end{table}%

The mass spectrum is extracted from the $\Lambda_c\to \pi(\pi\Sigma)_l$ mode, while the $\Lambda_c\to \pi(\pi\Sigma)_h$ mode is used to normalize the strength of the amplitude, as we will see below. Fortunately, most decay modes are experimentally observed, with the branching ratio of the order of several percents. If the precise measurement of the $\pi\Sigma$ spectrum around the threshold is performed, it will be feasible to extract the scattering lengths by the method explained in Sec.~\ref{subsec:expansion}.

\subsection{Threshold cusp effect}\label{subsec:cusp}

Let us consider the $\Lambda_{c}$ decay process in Fig.~\ref{fig:diagrams}, paying attention to the imaginary part of the loop function. To concentrate on the cusp phenomena, in this section, we simply ignore the diagrams other than those in Fig.~\ref{fig:diagrams}, assuming that the other final-state interactions  are slowly varying in the relevant energy region. The decay width of the process $\Lambda_{c}\to \pi(\pi\Sigma)_{l}$ can be calculated as
\begin{align}
    \Gamma
    = &
    \int d\Pi_3 \ \Sigma|\mathcal{M}|^2 ,
    \nonumber
\end{align}
where $\mathcal{M}$ is the relativistic scattering amplitude of the process, $d\Pi_3$ is the three-body phase space and $\Sigma$ denotes the spin summation. We denote the mass of the $\Sigma_h$ ($\pi_h$) by $M_h$ ($m_h$), and the invariant mass of the $(\pi\Sigma)_l$ system by $W$. The mass spectrum of the decay with respect to $W$ is given by
\begin{align}
    \frac{d\Gamma}{dW}
    = &
    \int d\tilde{\Pi} \ \Sigma |\mathcal{M}|^2,
    \nonumber
\end{align}
with $d\tilde{\Pi}=d\Pi_3/dW$. Since we are interested in the cusp structure which arises from the nonanalytic behavior of $W$, we concentrate on the amplitude as a function of $W$, assuming that the dependence on the other kinematical variables can be factorized. Integrating the other variables, we arrive at the expression
\begin{align}
    \frac{d\Gamma}{dW}
    =& \frac{M_{l} W}{16\pi^3M_{\Lambda_c}}
    \Sigma|\mathcal{M}|^2
    \int d\omega_{l}
    \Theta(1-A^2)
    \label{eq:spectrum} ,
    \\
    A=&
    \frac{(M_{\Lambda_c}-\omega_{\pi}
    -\omega_{l})^2
    -M_{l}^2-p_{\pi}^2-p_{l}^2}{2p_{\pi}p_{l}}
    \nonumber , \\
    \omega_{\pi}
    = &
    \frac{M_{\Lambda_c}^2-W^2+m_{\pi}^2}{2M_{\Lambda_c}}
    \nonumber , \\
    p_{\pi}
    = &
    \sqrt{\omega_{\pi}^2-m_{\pi}^2} ,
    \quad
    p_{l}
    =
    \sqrt{\omega_{l}^2-m_{l}^2}
    \nonumber ,
\end{align}
where $M_{\Lambda_{c}}$ is the mass of the $\Lambda_{c}$, $\omega_{l}$ ($\omega_{\pi}$) and $p_{l}$ ($p_{\pi}$) are the energy and momentum of $\pi_{l}$ (the primary pion), and $\Theta(x)$ is the step function.

To appreciate the threshold cusp effect, we focus on the property of the loop function $G(W)$ in Fig.~\ref{fig:diagrams}(b). The loop function can be written in the spectral representation as
\begin{align}
    G(W)
    = &
    \frac{1}{2\pi}\int_{W_{\text{th}}}^{\infty}dW^{\prime}
    \frac{\rho(W^{\prime})}{W-W^{\prime}+i\epsilon}
    +\text{(subtractions)} ,
    \nonumber
\end{align}
where the threshold energy is $W_{\text{th}}= M_h+m_h$ and the phase-space factor $\rho(W)$ is given by
\begin{align}
    \rho(W)
    = &
    2M_h \frac{q(W)}{4\pi W} ,
    \nonumber
\end{align}
with the three-momentum function
\begin{align}
    q(W)
    =& \frac{\sqrt{[W^2-(M_h-m_h)^2](W^2-W_{\text{th}}^2)}}{2W}
    \nonumber .
\end{align}
The real part of the loop function $G(W)$ depends on the subtractions, but the imaginary part can be determined only by the kinematics. Since the scattering amplitude with the diagram in Fig.~\ref{fig:diagrams} contains the loop function, we obtain the condition for the amplitude
\begin{align}
    \text{Im } \mathcal{M}(W)
    \propto \text{Im } G(W)
    = &
    -\frac{M_hq(W)}{4\pi W}
    \Theta(W-W_{\text{th}})
    \label{eq:imaginarypart} .
\end{align}
This means that the imaginary part of the amplitude appears suddenly at the threshold.

Considering the two diagrams shown in Fig.~\ref{fig:diagrams}, we can decompose the $\Lambda_c\to \pi(\pi\Sigma)_l$ amplitude into two parts:
\begin{align}
    \mathcal{M}(W)
    = &
    \mathcal{M}_0(W) + i\tilde{\mathcal{M}}_1(W) q(W)
    \quad  \text{for}\quad W>W_{\text{th}}
    \label{eq:amplitude} ,
\end{align}
with $\mathcal{M}_0(W)$ and $\tilde{\mathcal{M}}_1(W)$ being analytic functions of $W$ at the threshold $W_{\text{th}}$. Here we also assume that $\mathcal{M}_0(W)$ and $\tilde{\mathcal{M}}_1(W)$ have no imaginary part, and the extension to the complex amplitudes is discussed in Sec.~\ref{subsec:extension}. The amplitude~\eqref{eq:amplitude} satisfies the condition~\eqref{eq:imaginarypart}, because the $(\pi\Sigma)_h$ loop is the only source of the imaginary part in this process. Physically, the amplitude of the direct process (a) and the real part of the indirect process (b) are included in $\mathcal{M}_0$, and the amplitude corresponding to the imaginary part of the indirect process (b) is included in $i\tilde{\mathcal{M}}_1q(W)$. The function $q(W)$ can be analytically continued to $W<W_{\text{th}}$ where it becomes pure imaginary. For later convenience, we define the dimensionless quantity
\begin{align}
    \delta
    \equiv &
    \frac{\sqrt{[W^2-(M_h-m_h)^2](W_{\text{th}}^2-W^2)}}{2m_h W}
    =\frac{iq(W)}{m_h}
    \label{eq:delta} ,
\end{align}
so $\delta$ is real (imaginary) below (above) the threshold and $\delta^{2}=-|\delta|^{2}$ for $W>W_{\text{th}}$.\footnote{There is another branch point at $W= M_h-m_h$, but we will not consider this because the energy region cannot be reached in our analysis of $\pi\Sigma$ spectrum around the threshold.} The amplitude then can be rewritten as
\begin{align}
    \mathcal{M}(W)
    = &
    \mathcal{M}_0(W) + \tilde{\mathcal{M}}_1(W) m_h\delta
    \label{eq:amplitude2} .
\end{align}
Because of the property of $\delta$, the second term of Eq.~\eqref{eq:amplitude2} interferes with the first term below the threshold, while such an interference does not occur above the threshold.

Using the expression~\eqref{eq:amplitude2} and $\mathcal{M}^{*}=\mathcal{M}_0 + \tilde{\mathcal{M}}_1 m_h\delta^{*}$, we calculate the amplitude square as
\begin{widetext}
\begin{align}
    |\mathcal{M}|^2
    = &
    \begin{cases}
      (\mathcal{M}_0)^2 + (\tilde{\mathcal{M}}_1m_h)^2|\delta|^2
      & \text{for}\quad W>W_{\text{th}} \\
      (\mathcal{M}_0)^2
      +2\mathcal{M}_0 \tilde{\mathcal{M}}_1 m_h\delta
      + (\tilde{\mathcal{M}}_1 m_h)^2\delta^2
      & \text{for}\quad W< W_{\text{th}}
    \end{cases}
    \label{eq:ampsquare} .
\end{align}
\end{widetext}
Note that $\delta$ vanishes at the threshold, so the spectrum is continuous at $W=W_{\text{th}}$. On the other hand, its derivative with respect to $W$ is not continuous:
\begin{align}
    & \left.\frac{d|\mathcal{M}|^2}{dW}
    \right|_{W\to W_{\text{th}}-0}
    -\left.\frac{d|\mathcal{M}|^2}{dW}
    \right|_{W\to W_{\text{th}}+0} \nonumber \\
    \propto &\
    -\frac{2\mathcal{M}_0
    \tilde{\mathcal{M}}_1m_h M_h}{M_h+m_h}\frac{1}{\delta}
    +\mathcal{O}(\delta)
    \nonumber .
\end{align}
This means that the $(\pi\Sigma)_l$ spectrum is continuous but not smooth at the $(\pi\Sigma)_h$ threshold. This singular behavior is called the threshold cusp. Although we have assumed that $\mathcal{M}_0$ is real in the present case, the mechanism of the threshold cusp is the same even if $\mathcal{M}_0$ has an imaginary part, since the discontinuity is caused by the nonanalytic term $\delta$ as a function of $W$, as shown in Sec.~\ref{subsec:extension}. Thus, the cusp always occurs at the threshold due to the kinematical condition, but the simple interference pattern in Eq.~\eqref{eq:ampsquare} is realized only for the real valued $\mathcal{M}_0$ amplitude.

\subsection{Expansion of the amplitude and spectrum}
\label{subsec:expansion}

In order to extract the scattering length, it is desirable to parametrize the amplitudes around the threshold $W_{\text{th}}$. The aim of this section is to relate the $\pi\Sigma$ scattering length to the near-threshold behavior of the spectrum. Since we concentrate on the energy region around the $(\pi\Sigma)_h$ threshold, the variable $\delta$ should be small. As we will see below, the relevant energy region is $|W-W_{\text{th}}|\lesssim 10$ MeV, where the value of $\delta$ is $|\delta|\lesssim 0.37$. This means that the $\mathcal{O}(\delta^3)$ error is about 5 \% level.

Since the $\mathcal{M}_0$ amplitude is an analytic function of $W$, it has only even powers in the $\delta$ expansion:
\begin{align}
    \mathcal{M}_0(\delta)
    = &
    \mathcal{M}_0^{(0)}
    +\mathcal{M}_0^{(2)} \delta^2
    +\mathcal{O}(\delta^4) .
    \label{eq:M0expand}
\end{align}
The $\tilde{\mathcal{M}}_1$ part of the amplitude is related to the scattering length. Identifying this contribution as the imaginary part of the diagram in Fig.~\ref{fig:diagrams}(b), we can write the amplitude above the threshold as
\begin{align}
    \tilde{\mathcal{M}}_1(W) q
    = &
    -\mathcal{M}_0^h(W)
    \frac{M_hq}{4\pi W}
    \mathcal{M}_{h\to l}(W)
    \nonumber \\
    \tilde{\mathcal{M}}_1(W)
    = &
    \mathcal{M}_0^h(W)
    f_{h\to l}(W)
    \nonumber ,
\end{align}
where $\mathcal{M}_0^h$ is the amplitude of the weak $\Lambda_c\to \pi(\pi\Sigma)_h$ decay. The amplitude $\mathcal{M}_{h\to l}$ represents the transition amplitude for the $(\pi\Sigma)_h\to(\pi\Sigma)_l$ process and $f_{h\to l}$ is its nonrelativistic counterpart. Note that all the final-state interactions \textit{via} the strong interaction are implicitly included in $f_{h\to l}$. The $\mathcal{M}_0^h$ amplitude is an analytic function of $W$ so
\begin{align}
    \mathcal{M}_0^h(\delta)
    = &
    \mathcal{M}_0^{h(0)}
    +\mathcal{M}_0^{h(2)} \delta^2
    +\mathcal{O}(\delta^4) .
    \label{eq:Mhexpand}
\end{align}
The low-energy behavior of the nonrelativistic scattering amplitude can be parametrized by the scattering length $a_{h\to l}$. According to Eq.~\eqref{eq:def}, the scattering length is defined at the higher energy threshold, so we expand it in terms of $\delta$ as
\begin{align}
    f_{h\to l}(q)
    = &
    \left(\frac{1}{a_{h\to l}}-iq +\cdots\right)^{-1} \nonumber \\
    =& a_{h\to l}+a_{h\to l}^{2}m_{h}\delta + \cdots
    \label{eq:FSIexand} .
\end{align}
Using Eqs.~\eqref{eq:Mhexpand} and \eqref{eq:FSIexand}, we can express $\tilde{\mathcal{M}}_1$ as
\begin{align}
    \tilde{\mathcal{M}}_1(\delta)
    = &
    \mathcal{M}_0^{h(0)}a_{h\to l}
    +\mathcal{M}_0^{h(0)} m_{h}a_{h\to l}^2 \delta
    +\mathcal{O}(\delta^2)
    \label{eq:M1amp} .
\end{align}
Combining Eqs.~\eqref{eq:amplitude2}, \eqref{eq:M0expand}, and \eqref{eq:M1amp}, the expansion of $\mathcal{M}$ up to $\delta^{2}$ is given by
\begin{align}
    \mathcal{M}(\delta)
    = &
    \mathcal{M}_0^{(0)}
    +
    \mathcal{M}_0^{h(0)}m_{h}a_{h\to l}\delta \nonumber \\
    &
    +(\mathcal{M}_0^{(2)}
    +\mathcal{M}_0^{h(0)}m_{h}^{2}a_{h\to l}^2) \delta^2
    +\mathcal{O}(\delta^3)
    \nonumber .
\end{align}
The amplitude square is then given by
\begin{align}
    |\mathcal{M}|^2
    = &
    \begin{cases}
      A
      +C^{{\prime}}|\delta|^2
      +\mathcal{O}(|\delta|^4)
      & \text{for}\quad W>W_{\text{th}} \\
      A
      +B\delta
      +C\delta^2
      +\mathcal{O}(\delta^3)
      & \text{for}\quad W<W_{\text{th}}
    \end{cases} ,
    \label{eq:ampsquare2}
\end{align}
where the coefficients are given by
\begin{align}
    A
    =&(\mathcal{M}_0^{(0)})^2 \nonumber , \\
    B=&
    2\mathcal{M}_0^{(0)}\mathcal{M}_0^{h(0)}
    m_ha_{h\to l} \nonumber , \\
    C
    =&2\mathcal{M}_0^{(0)}\mathcal{M}_0^{(2)}
    +2\mathcal{M}_0^{(0)}\mathcal{M}_0^{h(0)}m_{h}^{2}a_{h\to l}^2
    \nonumber\\
    &+(\mathcal{M}_0^{h(0)})^{2}m_{h}^{2}a_{h\to l}^{2} ,
    \nonumber \\
    C^{\prime}
    =&
    -2\mathcal{M}_0^{(0)}\mathcal{M}_0^{(2)}
    -2\mathcal{M}_0^{(0)}\mathcal{M}_0^{h(0)}m_{h}^{2}a_{h\to l}^2
     \nonumber \\
    &+(\mathcal{M}_0^{h(0)})^{2}m_{h}^{2}a_{h\to l}^{2} .
    \nonumber
\end{align}
These coefficients can be extracted using the experimental spectrum, the three-body phase-space factor, and the fitting by a polynomial of $\delta$ around the threshold $W_{\text{th}}$. Since the $B$ coefficient is proportional to the scattering length, we can extract its absolute value as
\begin{align}
    |a_{h\to l}|
    = &
    \frac{|B|}{2m_h\sqrt{A}|\mathcal{M}_0^{h(0)}|}
    \nonumber ,
\end{align}
and the sign is given by
\begin{align}
    \frac{a_{h\to l}}{|a_{h\to l}|}
    = &
    \frac{\mathcal{M}_0^{(0)}}{|\mathcal{M}_0^{(0)}|}
    \cdot \frac{\mathcal{M}_0^{h(0)}}{|\mathcal{M}_0^{h(0)}|}
    \cdot
    \frac{B}{|B|}
    \nonumber .
\end{align}
The $\mathcal{M}_0^{h(0)}$ coefficient can be obtained as the leading contribution for the $\Lambda_c\to \pi(\pi\Sigma)_h$ process around the threshold. It is also possible to calculate $\mathcal{M}_0^{h}$ when the information of the weak process is well under control. If we determine the relative sign of $\mathcal{M}_0^{(0)}$ and $\mathcal{M}_0^{h(0)}$, the sign of the scattering length $a_{h\to l}$ is determined by the sign of the coefficient $B$. This information, together with the fitting of the $(\pi\Sigma)_l$ spectrum in the $\Lambda_c\to \pi(\pi\Sigma)_l$ process below and above the $(\pi\Sigma)_h$ threshold by Eq.~\eqref{eq:ampsquare2}, leads to the determination of the scattering length $a_{h\to l}$.

\subsection{Extension to the complex amplitude}
\label{subsec:extension}

So far we have assumed that the weak interaction amplitudes $\mathcal{M}_{0}$ and $\tilde{\mathcal{M}}_{1}$ are real. This is valid at the leading order, but several final-state interactions may bring an imaginary part as we discuss in Appendix~\ref{sec:kinematics}. Here we consider the possible modification of the formulation by the imaginary part of these amplitudes.

Since the overall phase of the amplitude does not contribute to the spectrum, we consider a relative phase between $\mathcal{M}_{0}$ and $\tilde{\mathcal{M}}_{1}$ amplitudes. The imaginary part other than Eq.~\eqref{eq:imaginarypart} is a smooth function of $W$, so we introduce a constant phase $e^{i\theta}$ to generalize Eq.~\eqref{eq:amplitude2} as
\begin{align}
    \mathcal{M}(W)
    = &
    \mathcal{M}_0(W) + \tilde{\mathcal{M}}_1(W)e^{i\theta}
     m_h\delta
    \nonumber .
\end{align}
with $\mathcal{M}_0$ and $\tilde{\mathcal{M}}_{1}$ being real. In this case, the amplitude square is given by
\begin{widetext}
\begin{align}
    |\mathcal{M}|^2
    = &
    \begin{cases}
      (\mathcal{M}_0)^2
      +2\mathcal{M}_0 \tilde{\mathcal{M}}_1 m_h|\delta|
      \sin\theta
      + (\tilde{\mathcal{M}}_1m_h)^2|\delta|^2
      & \text{for}\quad W>W_{\text{th}} \\
      (\mathcal{M}_0)^2
      +2\mathcal{M}_0 \tilde{\mathcal{M}}_1 m_h\delta
      \cos\theta
      + (\tilde{\mathcal{M}}_1 m_h)^2\delta^2
      & \text{for}\quad W< W_{\text{th}}
    \end{cases}
    \nonumber .
\end{align}
\end{widetext}
In this case, the linear $|\delta|$ term remains in the spectrum above threshold.

The expansion of the amplitude square in terms of $|\delta|$ is given by
\begin{align}
    |\mathcal{M}|^2
    = &
    \begin{cases}
      A
      +B^{{\prime}}|\delta|
      +C^{{\prime}}|\delta|^2
      +\mathcal{O}(|\delta|^4)
      & \text{for}\quad W>W_{\text{th}} \\
      A
      +B\delta
      +C\delta^2
      +\mathcal{O}(\delta^3)
      & \text{for}\quad W<W_{\text{th}}
    \end{cases} ,
    \nonumber
\end{align}
where the coefficients are given by
\begin{align}
    A
    =&(\mathcal{M}_0^{(0)})^2 \nonumber , \\
    B=&
    2\mathcal{M}_0^{(0)}\mathcal{M}_0^{h(0)}
    m_ha_{h\to l}\cos\theta \nonumber , \\
    B^{\prime}=&
    2\mathcal{M}_0^{(0)}\mathcal{M}_0^{h(0)}
    m_ha_{h\to l}\sin\theta
    =B\tan \theta
     \nonumber , \\
    C
    =&2\mathcal{M}_0^{(0)}\mathcal{M}_0^{(2)}
    +2\mathcal{M}_0^{(0)}\mathcal{M}_0^{h(0)}m_{h}^{2}a_{h\to l}^2
    \cos\theta
    \nonumber\\
    &+(\mathcal{M}_0^{h(0)})^{2}m_{h}^{2}a_{h\to l}^{2}  ,
    \nonumber \\
    C^{\prime}
    =&
    -2\mathcal{M}_0^{(0)}\mathcal{M}_0^{(2)}
    -2\mathcal{M}_0^{(0)}\mathcal{M}_0^{h(0)}m_{h}^{2}a_{h\to l}^2
    \cos\theta
    \nonumber \\
    &+(\mathcal{M}_0^{h(0)})^{2}m_{h}^{2}a_{h\to l}^{2} .
    \nonumber
\end{align}
The scattering length is
\begin{align}
    |a_{h\to l}|
    = &
    \frac{|B/\cos\theta|}{2m_h\sqrt{A}|\mathcal{M}_0^{h(0)}|} ,
    \nonumber \\
    \frac{a_{h\to l}}{|a_{h\to l}|}
    = &
    \frac{\mathcal{M}_0^{(0)}}{|\mathcal{M}_0^{(0)}|}
    \cdot \frac{\mathcal{M}_0^{h(0)}}{|\mathcal{M}_0^{h(0)}|}
    \cdot
    \frac{B/\cos\theta}{|B/\cos\theta|}
    \nonumber .
\end{align}
Thus, the scattering length can be extracted in the same way as before when the relative phase between $\mathcal{M}_{0}$ and $\tilde{\mathcal{M}}_{1}$ is under control. In practice, the relative phase mainly stems from the final-state interactions of the $\pi\pi$ scattering, which are well understood by the phase-shift analysis.

Even if the relative phase is not known in advance, the magnitude of the scattering length can be extracted from the coefficients of the linear terms:
\begin{align}
    |a_{h\to l}|
    = &
    \frac{\sqrt{B^{2}+(B^{\prime})^{2}}}{2m_h\sqrt{A}|\mathcal{M}_0^{h(0)}|}
    \nonumber .
\end{align}
In addition, $\cos\theta$ can be determined from the $\delta^{2}$ terms if we neglect the $\mathcal{M}_0^{(2)}$ term:
\begin{align}
    \cos\theta
    = &
    \frac{\mathcal{M}_0^{h(0)}}{\mathcal{M}_0^{(0)}}
    \frac{C-C^{\prime}}{C+C^{\prime}}
    \quad
    \text{for }
    \mathcal{M}_0^{(2)}= 0
    \nonumber .
\end{align}
In this way, extraction of the scattering length is possible for the complex amplitudes, when information of the final-state interaction and/or high-precision data of the decay spectrum are available.

\section{Estimation of the mass distribution}\label{sec:estimation}

So far we have discussed how to extract the $\pi\Sigma$ scattering lengths from the observed decay spectrum. In this section, we present  theoretical estimation of the mass spectrum~\eqref{eq:ampsquare2}, in order to examine the sensitivity of the cusp effect on the $\pi\Sigma$ scattering lengths.

\subsection{Input parameters}
\label{subsec:input}

To evaluate the mass spectrum, we need to determine the amplitudes for the weak process and the value of the scattering length. We first consider the weak process of the $\Lambda_c\to \pi\pi\Sigma$. Since we are not aiming at the construction of the realistic decay spectrum, we simply approximate the amplitude by the leading-order constant $\mathcal{M}_0=\mathcal{M}_0^{(0)}$ and $\mathcal{M}_0^h= \mathcal{M}_0^{h(0)}$, which would be sufficient for the present purpose. We first put $\theta = 0$ and the effect of the relative phase will be considered in the end of this section. The magnitude of these amplitudes are determined by the partial decay widths derived from the central values of the lifetime of the $\Lambda_c$ and the branching ratios given in Table~\ref{tbl:ratios}. The results are summarized in Table~\ref{tbl:weak}. For the $a^{0+}$ mode, the branching ratio to the lower energy channel is not known and we assume the same strength with the higher energy channel. In addition, the relative signs of the amplitudes have been determined by evaluating the quark diagrams of the weak decay in Appendix~\ref{sec:weak}. In the following, we adopt the central values for the numerical calculation of the spectra.

\begin{table}[b]
\caption{\label{tbl:weak} Strengths of the weak interaction vertices.}
\begin{ruledtabular}
\begin{tabular}{lll}
mode & $\mathcal{M}_0^{h}$ $(10^{-7}\text{ MeV}^{-1})$
 & $\mathcal{M}_0$ $(10^{-7}\text{ MeV}^{-1})$ \\
\colrule
$a^{-+}$ & $\phantom{-}1.46\pm 0.43$  & $\phantom{-}2.10\pm 0.58$  \\
$a^{00}$ & $\phantom{-}1.46\pm 0.43$  & $-1.49\pm 0.66$ \\
$a^{0+}$ & $-1.49\pm 0.66$ & $-1.49\pm 0.66$\footnote{Assumed to be the same with $\mathcal{M}_0^{h}$} \\
\end{tabular}
\end{ruledtabular}
\end{table}%

Next we consider the $\pi\Sigma$ scattering lengths. It is known that the $\pi N$ scattering length is well described by the leading-order term in ChPT, up to 10\%. Thus, as a first trial, we may adopt the leading-order ChPT to estimate the $\pi \Sigma$ scattering lengths. Higher-order contributions to the scattering lengths are calculated in the heavy baryon formalism~\cite{Liu:2006xja} and in the covariant formalism with the infrared regularization scheme~\cite{Mai:2009ce}. With the definition~\eqref{eq:def}, the leading-order term in ChPT gives the $\pi\Sigma$ scattering length for the channel $h\to l$ as
\begin{align*}
    a_{h\to l}
    =&
    \frac{M_h}{4\pi(M_h+m_h)}
    \frac{C_{h\to l}(m_h+\omega_l)}{4f^2} , \\
    &\omega_{l}
    =\frac{(M_{h}+m_{h})^{2}-M^{2}_{l}+m^{2}_{l}}{2(M_{h}+m_{h})}
    =m_{l}+\cdots ,
\end{align*}
where $f=92.4$ MeV is the pion decay constant and the ellipsis denotes the isospin breaking correction. The coefficient $C_{h\to l}$ is the group theoretical factor~\cite{Hyodo:2006yk,Hyodo:2006kg}, which takes the values $0$, $2$, and $-2$ for the $a^{-+}$, $a^{00}$, and $a^{0+}$ modes, respectively. Thus, the leading-order ChPT predicts
\begin{align}
    a^{-+}
    =& 0.00 \text{ fm},\quad
    a^{00}
    =  0.23 \text{ fm},\quad
    a^{0+}
    =  -0.23 \text{ fm}.
    \nonumber
\end{align}

\begin{table}[b]
\caption{\label{tbl:slengths} Estimation of the scattering lengths in units of fm. ChPT stands for the leading-order prediction in chiral perturbation theory. The other results are obtained in the resummation scheme for $I=0$ amplitude when the pole singularities are developed at the energies in parenthesis away from the threshold~\cite{Ikeda:2011dx}.}
\begin{ruledtabular}
\begin{tabular}{lrrrr}
   & $a^{I=0}$  & $a^{-+}$
   & $a^{00}$ & $a^{0+}$ \\
   \colrule
   ChPT           & 0.46    & 0.00    & 0.23    & $-0.23$ \\
   Resonance ($+31$ MeV)     & 1.20    & 0.25    & 0.48    & $-0.23$ \\
   Virtual state ($-6$ MeV) & 5.50    & 1.68    & 1.91    & $-0.23$ \\
   Bound state ($-10$ MeV)   & $-2.30$ & $-0.92$ & $-0.69$ & $-0.23$ \\
\end{tabular}
\end{ruledtabular}
\end{table}%

In the isospin basis, the coupling strengths are given by $4$, $2$, and $-2$ for $I=0$, $1$, and $2$ channels. The strength $C=2$ is the same with the $\pi N(I=1/2)$ channel, so we expect that the ChPT prediction works well. This is indeed the case for the $I=2$ scattering length, since the lattice QCD simulation by NPLQCD Collaboration~\cite{Torok:2009dg} found that $a_{\pi^{+}\Sigma^{+}}=-0.197\pm 0.017$ fm, which is comparable with the leading-order ChPT prediction of $-0.2294$ fm. On the other hand, $C=4$ in the $I=0$ channel is twice as strong as the $\pi N$ interaction so the resummation effect may be important. Indeed, it is found that the chiral $\pi\Sigma(I=0)$ interaction generates a resonance state by the single-channel resummation~\cite{Hyodo:2007jq}. The relation between the pole singularity around the $\pi\Sigma$ threshold and the $\pi\Sigma$ scattering length is studied in Ref.~\cite{Ikeda:2011dx}, which shows that the position and the nature of the pole are sensitive to the value of the scattering length. Depending on the nature of the lower pole of $\Lambda(1405)$, the typical $\pi\Sigma(I=0)$ scattering lengths are found as
\begin{align}
    a^{I=0}
    =
    \begin{cases}
     1.2 \text{ fm:} & \text{resonance with } E= + 31\text{ MeV} \\
     5.5 \text{ fm:} & \text{virtual state with } E=-6\text{ MeV} \\
     -2.3 \text{ fm:} & \text{bound state with } E=-10\text{ MeV}
    \end{cases} ,
    \nonumber
\end{align}
where $E$ denotes (the real part of) the pole singularity measured from the threshold.\footnote{The calculation in Ref.~\cite{Ikeda:2011dx} was done in the isospin limit. The resonance case is estimated by taking an average of two different solutions, A1 and B E-dep in Ref.~\cite{Ikeda:2011dx}.} It can be seen that the scattering length takes a large value when the pole is located close to the threshold, and the sign of the scattering length is inverted when a bound state appears. With these values for the $I=0$ scattering length, while the $I=1$ and the $I=2$ components are fixed as the values by the leading-order ChPT, we obtain the scattering lengths by use of Eqs.~\eqref{eq:amp}, \eqref{eq:a00}, and \eqref{eq:a0p} as shown in Table~\ref{tbl:slengths}. Even when $a^{I=0}$ is as large as 5.50 fm, the scattering lengths $a^{-+}$ and $a^{00}$ are not much enhanced, because of the $1/3$ factor in Eqs.~\eqref{eq:amp} and \eqref{eq:a00}. Note that $a^{0+}$ does not depend on the $I=0$ amplitude as observed in its isospin decomposition~\eqref{eq:a0p}.

\begin{figure}[tbp]
    \centering
    \includegraphics[height=4.5cm,clip]{Spectrum_mp.eps}
    \caption{\label{fig:Spectrum1}
    (Color online) Spectra of the $\pi^{-}\Sigma^{+}$ channel in the $\Lambda_{c}\to \pi^{+}(\pi^{-}\Sigma^{+})$ decay with several values of the $a^{-+}$ scattering length.}
\end{figure}%

\begin{figure*}[btp]
    \centering
    \includegraphics[height=5cm,clip]{Spectrum_00.eps}
    \includegraphics[height=5cm,clip]{Spectrum_0p.eps}
    \caption{\label{fig:Spectrum2}
    (Color online) Spectra of the $\pi^{0}\Sigma^{0}$ channel in the $\Lambda_{c}\to \pi^{+}(\pi^{0}\Sigma^{0})$ decay  [(a) and (b)] and the $\pi^{0}\Sigma^{+}$ channel in the $\Lambda_{c}\to \pi^{0}(\pi^{0}\Sigma^{+})$ decay (c), with several values of the scattering length. }
\end{figure*}%

\subsection{Examples of $\pi\Sigma$ spectrum}

Using the information given in the previous section, we calculate the $(\pi\Sigma)_{l}$ mass spectrum in the $\Lambda_{c}\to \pi(\pi\Sigma)_{l}$ process by use of Eq.~\eqref{eq:spectrum}. In Fig.~\ref{fig:Spectrum1}, we present the mass spectra of $\pi^{-}\Sigma^{+}$ channel in the $\Lambda_{c}\to \pi^{+}(\pi^{-}\Sigma^{+})$ mode for several values of $a^{-+}$. The dotted lines represent the case when the scattering length is set to be zero. The spectrum shows the pure phase-space distribution and no cusp structure appears, because of the absence of the $B$ term in Eq.~\eqref{eq:ampsquare2}. In this mode, $a^{-+}=0.00$ fm also corresponds to the prediction of the leading-order ChPT, as shown in Table~\ref{tbl:slengths}.

When a finite scattering length is adopted, the cusp structure appears (the solid lines and the dashed line). The cusp effect is not very significant for the case with $a^{-+}=0.25$ fm, but clear structures are visible for $a^{-+}=1.68$ fm and $a^{-+}=-0.92$ fm. In addition, the sign of the scattering length is reflected in the behavior of the lower part of the spectrum in comparison with the phase-space distribution.

Next, in Fig.~\ref{fig:Spectrum2}, we show the spectra of the $\Lambda_{c}\to \pi^{+}(\pi^{0}\Sigma^{0})$ decay and the $\Lambda_{c}\to \pi^{0}(\pi^{0}\Sigma^{+})$ decay with $a^{00}$ and $a^{0+}$, respectively. Again, the dotted lines represent the case when the scattering length is set to be zero. We observe that the prominent cusp structure is seen when the scattering length is as large as 0.5 fm. Because of the difference of the relative sign of the $\mathcal{M}_{0}$ and $\mathcal{M}_{0}^{h}$ amplitudes, the interference pattern in the $a^{00}$ mode is inverted from that in the $a^{-+}$ mode (see Table~\ref{tbl:weak}).

Let us compare three decay modes. In both the $a^{-+}$ and $a^{00}$ modes, the effect of the $I=0$ component is reflected in the cusp structure, so these modes can be used to extract the isosinglet scattering length. A nice feature of the $a^{-+}$ mode is the large branching fraction of the decay ($\sim$3.6\%) which is advantageous for the experimental observation. On the other hand, the scattering length vanishes in the leading-order ChPT, and, hence, the expected scattering length $a^{-+}$ by the resummation effect is not very large. The $a^{00}$ mode has a smaller branching ratio to the final state, but the value of $a^{00}$ is in general expected to be larger than $a^{-+}$ as shown in Table~\ref{tbl:slengths}, which causes a stronger cusp effect. The $a^{0+}$ mode is not useful to extract the $I=0$ component, and the expected cusp structure seems to be relatively weak. In addition, observing two neutral pions in the final state would be experimentally difficult. Nevertheless, once the precise decay spectrum is observed, this mode serves as a precise test of the ChPT prediction for the scattering lengths in $I=1$ and $I=2$ channels.

In order to estimate the accuracy of the spectrum measurement  for the feasible determination of the scattering length, we consider the deviation of the spectrum from the phase-space distribution
\begin{align}
    \text{dev}(a)
    =
    \frac{d\Gamma/dW(a)-d\Gamma/dW(a=0)}{d\Gamma/dW(a=0)}
    \label{eq:deviation} .
\end{align}
For a given $a$, the magnitude of this deviation provides the lower limit of the experimental accuracy to extract the scattering length. We also note that the deviation is always zero at the higher energy threshold $W_{\text{th}}=M_{h}+m_{h}$, so the phase-space distribution can be normalized at this point. In Fig.~\ref{fig:Dev_mp}, we show the deviation plot for the $\Lambda_{c}\to \pi^{+}(\pi^{-}\Sigma^{+})$ decay with several values of the scattering length $a$. We observe that accuracy of about 20\% (10\%) is required to determine the scattering length of $|a|=1$ fm (0.5 fm).

\begin{figure}[tbp]
    \centering
    \includegraphics[height=5.5cm,clip]{Dev_mp.eps}
    \caption{\label{fig:Dev_mp}
    (Color online) Deviations from the phase-space distribution defined in Eq.~\eqref{eq:deviation} for the $\Lambda_{c}\to \pi^{+}(\pi^{-}\Sigma^{+})$ decay with several values of the scattering length $a$.}
\end{figure}%

We also study the effect of the relative phase between $\mathcal{M}_{0}$ and $\tilde{\mathcal{M}}_{1}$. As discussed in Appendix~\ref{sec:kinematics}, the main source of the contamination process to the $\Lambda_{c}\to \pi^{+}(\pi^{+}\Sigma^{-})\to \pi^{+}(\pi^{-}\Sigma^{+})$ decay is the $\pi\pi$ rescattering. If the primary $\pi^{+}$ interacts with the $\pi^{+}$  in the intermediate state, the $\tilde{\mathcal{M}}^{1}$ has an imaginary part. This is the $\pi\pi$ scattering in the isospin $I=2$ channel. The relevant energy region of the $\pi\pi$ invariant mass is about 400--800 MeV, and the phase shift of this $\pi\pi$ channel ranges between $-5^{\circ}$ to $-20^{\circ}$, with almost linear energy dependence~\cite{Oller:1998hw}. Although the phase depends on the invariant mass of the $\pi\pi$ pair, we may represent the $\pi\pi$ rescattering effect by a single energy-independent relative phase. Thus, for a rough estimation, we introduce an energy-independent relative phase $\theta=-12^{\circ}$ and calculate the spectrum with the formulas in Sec.~\ref{subsec:extension}. The results are shown in Fig.~\ref{fig:Spectrum_phase}. One observes that the spectrum is slightly modified from Fig.~\ref{fig:Spectrum1}, especially above the threshold. The existence of the relative phase affects the interference pattern of the two amplitude, while the cusp structure itself remains, as discussed in Sec.~\ref{subsec:extension}.

\begin{figure}[tbp]
    \centering
    \includegraphics[height=4.5cm,clip]{Spectrum_mp_phase.eps}
    \caption{\label{fig:Spectrum_phase}
    (Color online) Spectra of the $\pi^{-}\Sigma^{+}$ channel in the $\Lambda_{c}\to \pi^{+}(\pi^{-}\Sigma^{+})$ decay with several values of the $a^{-+}$ scattering length with the relative phase $\theta=12^{\circ}$.}
\end{figure}%

\section{Summary}\label{sec:summary}

We study the $\pi\Sigma$ mass distribution in the $\Lambda_{c}\to \pi\pi\Sigma$ decays to extract the $\pi\Sigma$ scattering lengths. The threshold cusp effect is discussed in detail, and the relation between the $\pi\Sigma$ scattering length and the mass distribution is derived. We show that the $\pi\Sigma$ scattering length can be extracted by the expansion of the observed spectrum around the cusp structure.

We then evaluate the $\pi\Sigma$ spectrum for several values of the scattering lengths obtained by chiral perturbation theory and the resummation technique. It is found that, if the scattering length is as large as $0.5$ fm, a substantial cusp structure will be observed with about 10 \% deviation in the experimental data. This value of the scattering length corresponds to the case when the $I=0$ $\pi\Sigma$ scattering amplitude has a bound or virtual state about 10 MeV below the threshold. Thus, the analysis of the cusp structure will give important information on the $\pi\Sigma$ interaction around the threshold.

Note, however, that we have presented a rough estimation of the spectrum and there are several other contributions to the same process which are not included in the present calculation. A detailed Dalitz analysis of the $\Lambda_{c}\to \pi\pi\Sigma$ process is highly desired for the calibration of the theoretical model of the weak process as well as for the investigation of the strong final-state interactions in the $\pi\Sigma$ channel.

In the $\Lambda_{c}$ decay process, it is possible to provide two constraints on the three different isospin component of the $\pi\Sigma$ scattering lengths. To complete the determination of all three isospin components, for instance, we need to determine the $I=2$ component by the lattice QCD simulation~\cite{Fukugita:1994ve,Torok:2009dg,Ikeda:2010zz}.

\begin{acknowledgments}
The authors are grateful to Dr. Yoichi Ikeda and Professor Wolfram Weise for useful discussions.
T.H.\ thanks the support from the Global Center of Excellence Program by MEXT, Japan, through the Nanoscience and Quantum Physics Project of the Tokyo Institute
of Technology.
This work was partly supported by the Grant-in-Aid for Scientific Research from
MEXT and JSPS (Nos.\
  19540275,
  21840026,
  and 22105503).
\end{acknowledgments}

redpajama_set_name: RedPajamaArXiv


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text:
Rockies Draft
MLB Draft 2017: Rockies select RHP Tommy Doyle with 70th pick
The Rockies chose Virginia's closer with their second overall pick
By Eric Garcia McKinley and Ryan Schoppe Jun 12, 2017, 9:41pm MDT
Share All sharing options for: MLB Draft 2017: Rockies select RHP Tommy Doyle with 70th pick
The Colorado Rockies chose right-handed pitcher Tommy Doyle with the 70th overall in Competitive Balance Round B of the 2017 draft. Doyle comes out of the University of Virginia, where he was the team's closer. Baseball America ranked Doyle 136 in its top 500 draft prospects list.
MLBPipeline.com's scouting report on Doyle has his fastball sitting in the low-90s, though it has been clocked as high as 97. His slider may be his best off-speed pitch. If the Rockies intend to leave him in relief, those two pitches will be enough. If they plan to transition him to starting,he'll need to work on his other off-speed offerings.
Doyle had a 1.87 ERA in 33 2⁄3 innings of work for the Cavaliers. He made 23 appearances this season, all in relief, and earned 14 saves. He struck out 38 and walked 10. His final season in Virginia was by far his best as he seemed to thrive in the closer's job.
For his college career, Doyle pitched in 61 games, making seven starts and had a 3.87 ERA. He struck out 104 and walked 47 in 121 innings.
B (70): @Rockies select Virginia RHP Tommy Doyle. https://t.co/PwaEJTBUl4 #MLBDraft
— MLB Draft Tracker (@MLBDraftTracker) June 13, 2017
This is the second draft selection the Rockies made. With their second round pick, the Rockies chose high school third baseman Ryan Vilade. It was the 48th overall selection of the draft.
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MLB Draft 2017: Rockies sign 48th overall pick Ryan Vilade (3B, Stillwater HS, Okla.)
MLB Draft 2017: Where are they now
Rockies select RHP Tommy Doyle with 70th pick
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text:
Radio Prague - EN
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Sobotka: France has rejected populism, nationalism and isolation
Emmanuel Macron, photo: ČTK
Czech politicians have for the most part welcomed the victory of Emmaneul Macron in France's presidential election run-off on Sunday, with the prime minister and foreign minister among the first to congratulate the centrist candidate following his resounding victory over the anti-EU populist Marine Le Pen of the Front National.
Soon after the En Marche! leader's victory was announced, the Czech prime minister, Bohuslav Sobotka, tweeted his congratulations to the new French president. He said he was glad that voters had rejected populism, nationalism and isolation, deciding for a France that would be a proud and strong part of the European Union.
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Czech Foreign Minister Lubomír Zaorálek was also quick to respond to Mr. Macron's crushing win, saying that the French had not just voted for a president but for a European future. He said it was important at the present time that France play a strong and constructive role in the EU.
Culture Minister Daniel Herman said reason and responsibility had now triumphed in France, Holland and Austria, and expressed the wish that the same thing would happen in the Czech Republic.
The Czech president on Monday sent a telegram of congratulations to Mr. Macron. Miloš Zeman said he looked forward to excellent bilateral relations and invited the president-elect on a state visit to the Czech Republic.
The chairman of the Christian Democrats, Pavel Bělobrádek, said it was good news that a pro-European politician had won the closely watched vote. However, it remained to be seen whether Mr. Macron would understand the problems of new EU members, he said.
ANO chief Andrej Babiš congratulated the new French president, saying he had expected his victory. Mr. Babiš said, however, that Mr. Macron's views on migration and further European integration were unrealistic and that he hoped the new French leader would be open to argument. In addition, Mr. Macron will find it very difficult to change France's economic situation, Mr. Babiš said.
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Petr Fiala, leader of the right-wing opposition Civic Democrats, said Marine Le Pen's defeat was good news. But it would be hard to rejoice over Mr. Macron's win as he had not put forward a good solution to the EU crisis, he said.
TOP 09 MEP Jiří Pospíšil said he too had reservations over Emmaneul Macron. However, his convincing triumph was good news, as Ms. Le Pen would have broken up NATO and the EU, in Mr. Pospíšil's view.
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text:
McRobert inspects and relines deteriorated pump station
In 2017, trenchless contractor McRobert completed the structural relining of a Type 180 pump station in WA.
McRobert Contracting Services initially conducted a level two 3D laser scan of a sewer pump station in Mandurah, in the Peel Region of Western Australia in 2016.
The inspection revealed all internal concrete surfaces had been severely affected by biogenic sulphide corrosion. Significantly, it showed over 100 per cent of the concrete cover had deteriorated from the lower sections of the wet well walls.
In 2017, McRobert was subsequently contracted to complete the structural relining of the pump station inlet chamber and wet wells, using it's patented relining methodologies.
The wet well walls ready for pH tests and reinforcement repairs.
Due to the extent of the deterioration, the contractor performed concrete and reinforcement repairs to the walls of the pump station, prior to installing rigid PVC as per the company's patented whaler system. Initially, the walls were cleaned and loose corroded material from the walls was removed until only sound concrete remained.
pH testing was completed to ensure this was achieved. At this stage, McRobert completed a secondary laser scan to determine the true extent of the deterioration, which was illustrated to be significantly more than expected.
From the results of the laser scan, the company was able to accurately fabricate all required components for the structural relining.
Pump station prior to McRobert completing structural relining.
Steel reinforcement repairs were completed on the walls where reinforcement bars were exposed and corroded. McRobert's lining system was then employed to cover the existing walls, essentially rebuilding the initial structure with a new 12 mm thick PVC lining and minimum 40 mm of grout between the existing concrete and new PVC wall.
A 3D point cloud illustration outlining data collected during the initial inspection of pump station.
The contractor then removed the original benching from the inlet chamber and wet wells, before fabricating and installing new benches made from a combination of both rigid and flexible PVC. All internal surfaces were now fully plastic lined and welded. Two penstocks were installed to the inlet chamber and all new gatic lids were retrofitted to the existing plastic-lined top slab.
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The inlet chamber with penstocks post-rehabilitation.
This article was featured in the March edition of Trenchless Australasia. To view the magazine on your PC, Mac, tablet, or mobile device, click here.
For more information visit the McRobert website.


Android Oreo 8.0 based AICP 13 for Yu Yureka is now available to download via an OFFICIAL build. This post provides the download link to the AICP 13 Oreo ROM for Yu Yureka and guides through the installation process of the same. This AICP 13 Oreo ROM for Yu Yureka is brought to you by developer thakurfazer55.
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THIS IS AN INITIAL BUILD WHICH MAY NOT BOOT AT ALL. HAVE A BACKUP BEFORE FLASHING THIS AND TRY AT YOUR OWN RISK. Installing a custom ROM requires an unlocked bootloader on Yu Yureka, which may VOID your warranty and may delete all your data. Before proceeding further you may consider backup all data on the phone. Understand that you are the only person making changes to your phone and I cannot be held responsible for the mistakes done by you.
First flash the Yu Yureka AICP 13 ROM ZIP from device. Then flash the GApps zip from your device memory.
Reboot and Enjoy Android Oreo with AICP 13 ROM on Yu Yureka.
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