1997 Research Experiences for Undergraduates Program

National Radio Astronomy Observatory
Research Projects by NRAO Site

There will be four students in the 1997 NSF Research Experience for
Undergraduates (REU) program at NRAO-Charlottesville. Highlights of
the program will include a series of introductory level lectures on aspects
of astronomy, particularly radio astronomy, spread over a few weeks.
These lectures are intended to aquaint the students with the research
which various staff members carry out.

Summer students from Green Bank and Charlottesville met at a get-together
with mentors and lecturers in Charlottesville.

The students will enjoy an informal get-together with astronomers from
the University of Virginia at lunch, and from NRAO in the evening, followed
by a visit with graduate students from the
University's Astronomy Department.

Later in the summer, the Charlottesville students will visit Green Bank to
use the NRAO telescopes located there, to meet members of the Green Bank
staff, and to attend the annual picnic.

The students will give a series of 15 minute talks on their projects during
a lunch symposium in Charlottesville before they begin leaving for the summer.
They will produce short reports describing their summer research.

One highlight will be the placing of
the surface onto the Green Bank telescope
( GBT ),
the world's largest steerable
telescope. It is an offset parabaloid, 110m across the longest axis,
incorporating 16 million lbs of steel in the moving structure.
The surface is now nearly complete on the ground, where it must
be assembled first with supports. During June, the supports will be
removed and the surface allowed to sag so that measurements may be made
which will assure accurate mounting on the support structure. Then it
will be disassembled in sections and moved by crane to the final position
on the support structure. This will be particularly interesting. Although
we have the largest crane in the US on site, standing some 400 feet high and
delivered in five dozen tractor trailers, it cannot reach the whole surface
of the telescope. The plan is for the central section to be moved first,
after which an auxiliary crane will be erected in the central hole. Distant
sections will then be snatched up by the central crane, and handed off in
midair to the larger crane, which will hoist them to the surface. This will
occur in July through the early fall, and we will go to Green Bank for
observations, so should be able to watch the process.

During the course of the summer, the students will conduct a short
observing project in Green Bank on the 43m telescope, and tour the
Green Bank Telescope, in the final phase of construction this summer.
The 40 ft
telescope there is a student telescope, open for any project which
studets would like to carry out on it (though its instrumentation is limited).
If there is interest, we may carry out, probably remotely, a project on
the VLA or 12m telescope in Tucson.

We're very excited about the
Millimeter Array,
which was selected as the
top priority for a new astronomical instrument in the 90s back at the
beginning of the decade by the Astronomy Survey Committee. It is in the
President's budget request this year.

Local Radio Luminosity Functions of Active Galactic Nuclei

The project is to refine the determination of the local radio
luminosity functions of active galactic nuclei (AGN) and normal
galaxies based on flux density measurments from the NVSS 20 cm survey.
This survey detects roughly half the nearby galaxies. Previous work has
used approximately 4000 UGC galaxies with accurate position and using
IRAS 60 micron flux densities to distinguish AGN from normal galaxies.
One activity of the student would be to invesitgate individual objects
of uncertain classification. Another is to help prepare the results
for publication.

Correlations of the NRAO VLA Sky Survey with Other Objects

The main project which I am working on now is the NRAO VLA Sky Survey
(NVSS). This is the largest radio survey ever made, and it will yield
almost 2 X 10^6 sources by the time the data reduction is finished
sometime this summer. The NVSS is sensitive enough to detect radio
emission from most nearby (D < 100 Mpc) galaxies, a mixture of
"normal" galaxies, starburst galaxies, and galaxies containing massive
black holes. The radio positions are sufficiently accurate for
cross-identifications with sources found in other wavebands (e.g.,
far-infrared sources detected by the IRAS satellite or X-ray sources
found in the ROSAT survey). In fact, the superior NVSS positions
often allow the far-infrared or X-ray sources to be optically
identified with faint galaxies and quasars for the first time. You
could work on a project of your choice using the NVSS and other data
to study starburst galaxies, X-ray galaxies, etc.'
Mr. Kaplan's email address is kaplan@spacenet.tn.cornell.edu

Seeking High Velocity Neutral Hydrogen in NGC1300

The summer student will work with me on a search for high-velocity
neutral hydrogen using Very Large Array observations of the spiral galaxy
NGC 1300. The student will calibrate and reduce the VLA observations using
AIPS techniques that have been recently developed. The Groningen Image Processing
System (GIPSY) will be used to model NGC 1300 for the purpose of identifying
high-velocity neutral hydrogen. The observations will be compared with optical
images that I have already obtained and reduced. The star-formation rate in the
galaxy will be estimated from IRAS obserations available via the Internet, and
from VLA radio continuum data.

Hot Formaldehyde or Molecules in Comet C/1995 O1 Hale-Bopp

The student will have a choice of projects, both of which should lead to
publications. In one, we will investigate how to employ observations of
the submillimeter spectrum of formaldehyde to constrain conditions in
regions of massive star formation. Observations from the CSO are already
in hand; a preliminary
report was delivered at the Toronto AAS meeting.
Alternately, the student will help in the reduction and interpretation of
observations of molecular emission from Comets
Hyakutake and
Hale-Bopp.
Mangum and I hope to obtain an image of Hale-Bopp in various lines of
formaldehyde and methanol to augment data already in hand. This data should
reveal the temperature structure of a cometary coma for the first time.

NRAO/Socorro 1997 Research Experience for Undergraduates (REU)
Program

The summer REU program at NRAO/Socorro in 1997 consists of 4 main categories
of activity:

The 1997 REU program at NRAO/Socorro is under the direction of
Min Yun , assisted by
Jim Herrnstein and
Tim Bastian. Drs. Yun and Herrnstein are
Jansky Postdoctoral Researchers
at NRAO/Socorro, and Dr. Bastian is a member of the scientific research staff.

Student Research Projects

If we were really smart, we wouldn't be standing there! Student tour of Kitt Peak. (photo by S. Redfield)

Each of the REU students will work with one or more advisors on one or more
projects throughout the summer. This is the main focus of the program, and
the majority of the students' time will be spent on these research endeavors.
These projects involved observing, data reduction and analysis, equipment
development, and theoretical studies. At the end of the program, each student
gave a lunch talk explaining the main project(s) he or she worked on during
the summer. The possibility exists for the students to present their original
research at scientific meetings deemed appropriate by their advisor(s).
Following is a detailed list of the specific projects carried out by the
NRAO/Socorro REU students:

Robin McGary,
of Furman University
works with Miller Goss
on

Proper Motions of a Group of Pulsars

The project is to determine the proper motions of a group of about
20 pulsars using VLA data . The observations that exist now
are three epochs ; fall 1992, early 1994 and mid 1995 - all A array data.
The VLA was used in a gating mode to observe the pulsars using
the Princeton timing machine. One IF is gated and the other is not;
the latter is used to observe calibrators and background sources .
The psr positions are observed with higher signal to noise in the
first IF; the postion reference is set by the second IF. The purpose
of the project is to reduce the data and determine the psr positions
after correcting for a number of effects .
RThe collaborators are Goss, Thorsett ( Princeton ) and Fruchter ( Space
Telescope ).

Spectral Structure of 3C84

Together with Rene Vermeulen (NFRA) I've been investigating the low
frequency structure of 3C84 = NGC 1275 using the VLBA (Taylor \&
Vermeulen 1996, ApJL 457, L69). This famous radio source is
relatively nearby at z=0.0172 and thus makes an excellent "laboratory"
for studying the physics of AGN and their environment. This source
consists of a jet expanding subluminally to the south out to a total
length of 0.1" (24 pc) at 20cm, and a free-free absorbed counterjet
seen so far only at shorter wavelengths a few parsecs north of the core
(Vermeulen et al 1994, ApJL 430, L41; Walker et al 1994; ApJL 430, L45).
We have carried out VLBA observations at 20, 50 and 90 cm (project
BV14) of 3C84 in order to study the overall extent of the radio source
and its spectrum. A particularly interesting possibility is that the
northern jet may become detectable at low frequencies once it has
emerged from behind the nuclear disk. A summer student working on
this project would learn about the physics of AGN and the reduction of
VLB data, including high dynamic range imaging.

VLBA Imaging of a Seyfert Galaxy

We have imaged several Seyfert galaxies with the VLBA, and recently
had proposal BU008 approved for four more objects, which would be
observed on February 5. The observations of each galaxy would
be made at several different frequencies: 18 cm, 6 cm, and either
3.6 or 2 cm. Most would be phase-referencing observations, but
one galaxy, Mrk 348, is definitely strong enough so that phase
referencing will not be required. We would basically ask a
summer student to learn how to reduce VLBA data and to process
a single galaxy, probably Mrk 348 because it will be the strongest
source. The results would be continuum images and measurements
of the spectrum of the source components. Ultimately, when we
have all 8 galaxies processed, we hope to make some preliminary
estimate of whether there are differences in the VLBI structures
of Seyfert 1 and Seyfert 2 galaxies; potentially, the student
might also work on this aspect of the project. It is hoped that
there will be compact components near the core of at least some of the
four galaxies we observe in February, so that a second epoch might be
proposed later to check for motions.

VLBA Phase Stability

By summer 1997 nearly two years of VLBA phase-referencing test data
taken to examine the phase stability at the various antennas will be
available (~20 experiments). Analysis of this data involves the
characterization of the antenna phase stability as a function of
weather, season, time-of-day and target-calibrator separation. Other
factors such as calibrator structure and ionospheric effects could also
be explored if time allows. The results of this analysis would be of
immediate interest to the VLBI/VLBA community, and would certainly be
published.

Relative Elemental Enrichment of the NGC1232 HII Regions

Ms. Bryant will study of the relative elemental enrichment of HII
regions in NGC 1232. This summer student project is part
of a larger project to understand the production/retention
of nitrogen and oxygen in spiral galaxies. By looking at
one galaxy in detail, we will attempt to constrain the
effects of delayed delivery of nitrogen and local mixing.
The project will include some data reduction of optical
spectra obtained with the Palomar 5m, analysis of emission
line strengths to determine abundances, and the creation of
code to model nitrogen and oxygen enrichment and mixing
processes in a differentially rotating system.

Radio Properties of a FIR-selected Complete Sample of Galaxies

Mr. Reddy will perform a large statistical study of radio properties of a
FIR selected complete sample of galaxies taken from the new 1.2 Jy
catalog compiled by M. Strauss. The main part of the project
is to cross-correlate the new Strauss catalog with the FIRST
and NVSS database and obtain the radio and FIR data on a well
defined complete sample of galaxies. The radio-FIR correlation
and redshift dependent properties will be analyzed from the
new database. There are other published studies of radio-FIR
relation, but none with this large sample and well defined
selection critiria. The results should be publishable and
should be presented by the student in a scientific meeting
afterwards.

Lectures, etc...

Several lectures about radio astronomy and interferometry will be presented,
allowing the students to obtain a good understanding of the technique. Talks
were also given on general topics in astronomy, presented by members of the
scientific staff. The astronomy talks were designed to give the students an
understanding of what sort of research goes on at NRAO, and in radio astronomy
in general. The detailed list of lectures and events for the summer is in the
following table.

1997 Calendar of Events -- New Mexico

This is the list of student lectures and other organized events for
the summer students. Many of the future events are only tentatively scheduled.

Other Potential Lectures

Green Bank, West Virginia (NRAO 43m and 100m Telescopes)

Students conducting their research at the NRAO Green Bank Site
in West Virginia included the students in the list below, along with
others. The program at Green Bank is under the direction of Dr. Ron Maddalena.

If we were really smart, we wouldn't be standing there! Student tour of 43m telescope takes them onto its surface, pointing skyward.

The summer students prepare for a caving expedition. From left
to right, Kevin Finn, Jennifer LaRocque, Steve Hicks, Lisa Wray,
Buck Creel. Photo by R. Maddalena.

Other Events Open for Student Participation

Weekly (Thursday) astronomy lunches
May 5-6 -- NRAO Internal Symposium
May 9 - 16 -- NRAO/Glenville State College Institute for
Preservice Teacher Preparation.
May 19 - 24 -- Chattaqua course
Depending upon the weather, we'll try to get
into the dish of
the 140-ft this Wed.
July 1 (or thereabouts) -- Student/Staff appreciation party
July 3 -- Possibly tour guides for the National Youth Science Camp
July 7-8 -- Visit to Charlottesville
July 11 -- "Contact" opens at theaters near you (but not us--we're making the contact!)
July 25 -- Charlottesville students visit Green Bank
July 26 -- Picnic
August 3-16 -- NRAO/WVU Institute for Inservice Teacher Enhancement

Buckner Creel, of Rose-Hulman Institute of Technology
works with Mark Clark
on

Development of an Additional User Interface to the GBT

Phase 1: Develop a UNIX shell level interface to the GBT monitor and
control interfaces. This would involve the development of seven small
C++ programs (see manual page GBT(1) attached) based on code already
written for the Spectral Processor (sps, abort, and spe; see Spectral
Processor documentation), but generalized to handle all GBT
interfaces. These programs will provide access to all parts of the
system, just as the current console or Glish interfaces.

Phase 2: Define a Tcl/Tk interface on top of the seven programs
described in Phase 1.

Helium Abundance in the Galaxy

Observations of helium radio recombination lines have been observed
with the 140 Foot telescope in a sample of HII regions in the Galaxy.
The goal is to produce accurate 4He/H abundances.
The project would
require the student to help in the observations (if time is
allocated), the data reduction and analysis.

Peter Fritsch, of West Vriginia University
works with George Behrens
on

Updated Software for the Outdoor Antenna Range

Ian Hoffman, of Colgate University
works with Jay Lockman
on

HI survey of the galactic plane with the 140-ft telescope

The 140-foot telescope at the National Radio Astronomy Observatory in Green Bank, West Virginia is being used to map the 21-cm (1420.40580 MHz)
spectral line emission of neutral hydrogen (HI) in the region 65° New data was taken this July. Data reduction algorithms were designed and improved.

Kevin Finn, of Purdue University
works with Wes Grammer
on

IF System Hardware for the Green Bank Telescope

Darryl Blackburn, of Radford University
works with Joe Brandt
on

A Message System Browser for the GBT

Darryl is helping Joe to develop a enhanced message system
browser intended for use on the Green Bank Telescope. The interface is being
implemented in the Java langauge, the latest in graphical
user interface technology.

Tucson, Arizona (NRAO 12m and VLBA Telescopes)

Students conducting their research at the NRAO Tucson Site
in Arizona included Matt Pickard and Ryan Roth. The
program in Tucson is under the direction of Jeff Hagen. As the
NRAO offices are across the street from KPNO/NOAO offices, the REU
group shares in the activities of the NOAO REU program there.

Images of the Serpens Star Formation Region

Images of the CS and H2CO emission toward the Serpens star
formation region have been made using the On-The-Fly (OTF) observing
technique at the 12m telescope. The project will involve analysis of
these data to (1) derive the spatial correspondence between the CS and
H2CO emission; (2) measure the spatial density and kinetic temperature
in the cores which compose the region; (3) study the kinematic
structure of each core to investigate the presence of infall, outflow,
or rotation; (4) develop a model of the evolution of the high-density
cores within the region. The projects will require that the student
become versed in the use of AIPS and an LVG radiative transfer model.

Ryan Roth, of Embry Riddle Aeronautical University
works with Jingquan Cheng
on