REU Site: Research Experiences for Undergraduates in Astronomy at
Cerro Tololo Inter-American Observatory
Annual Project Report (Year 1) 1 October 2011 – 30 September 2012
Submitted to the National Science Foundation
Nigel Sharp, PhD, NSF Program Officer
Pursuant to Cooperative Support Agreement No. AST-1062976
Cooperative Agreement No. AST-0809409
NOAO is operated by the Association of Universities for Research in Astronomy (AURA)
under cooperative agreement with the National Science Foundation
NATIONAL OPTICAL ASTRONOMY
OBSERVATORY
2012 CTIO REU Students and CTIO Director Dr. R. Chris Smith. From left to right, back row: Samuel Meyer and Dr. R. Chris Smith; middle row: Bezia Laderman and Clara Thomann, Front Row: Melissa Butner, Kimberly Emig, and Christine Gilfrich.
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Contents
1 ACTIVITIES AND FINDINGS ............................................................................................ 1
1.1 Research and Education Activities..................................................................... 1
1.1.1 Overview of Program Award .............................................................. 1
1.1.2 Science Program .................................................................................. 1
1.1.3 Student Activities & Local Arrangements ........................................... 7
1.1.4 Conclusions ......................................................................................... 8
1.2 Findings .............................................................................................................. 8
1.3 Training and Development ............................................................................... 10
1.4 Outreach Activities .......................................................................................... 10
2 JOURNAL PUBLICATIONS ............................................................................................. 11
3 WEB/INTERNET SITE ...................................................................................................... 12
4 OTHER SPECIFIC PRODUCTS ....................................................................................... 12
5 CONTRIBUTIONS .............................................................................................................. 13
5.1 Contributions within Discipline ....................................................................... 13
5.2 Contributions to Human Resource Development............................................. 13
5.3 Contributions to Resources for Research and Education ................................. 14
5.4 Contributions beyond Science and Engineering .............................................. 14
Research Experiences for Undergraduates in Astronomy at
Cerro Tololo Inter-American Observatory
Annual Project Report (Year 1)
1 October 2011 – 30 September 2012
Nicole S. van der Bliek, Principal Investigator
David J. James, Co-Principal Investigator
For submission to the National Science Foundation
Pursuant to Cooperative Support Agreement No. AST-1062976
30 June 2012
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1 ACTIVITIES AND FINDINGS
1.1 RESEARCH AND EDUCATION ACTIVITIES
1.1.1 Overview of Program Award
The 2012 National Optical Astronomy Observatory (NOAO) Research Experiences for
Undergraduates (REU) Program at Cerro Tololo Inter-American Observatory (CTIO) provided an
opportunity for six US undergraduate students to participate in independent, supervised research
activities in astronomy in collaboration with members of the scientific staff. The program is
supported by the rich scientific environment and research facilities of CTIO’s La Serena offices, as
well as ready access to the national observatory facilities on Cerro Tololo itself. Together, these
facilities provide a framework that introduces students to both the operations of a major observatory
and the capabilities of a variety of instruments while they are actively engaged in current
astronomical research. Building upon these resources, the program includes an introduction to
observational techniques and provides observing experiences for the participants. Furthermore, the
program offers a unique cultural opportunity for participants to live in a foreign country and work
alongside Chilean students who are doing similar research projects.
Six undergraduate students from the US, selected from a total of 17 qualified applicants from
US institutions, participated in the 2012 REU program at CTIO. Announcements were sent to over
800 college and university science and mathematics departments and career placement offices in the
US and Puerto Rico. This promotional campaign targeted the Hispanic Association of Colleges and
Universities (HACU) as well as Historically Black Colleges and Universities (HBCU). The program
was advertised on the CTIO REU program website (http://www.ctio.noao.edu/REU/reu.html) and in
the NOAO Newsletter. Advertising for the 2012 program was accomplished in August 2011, as
planned; promotional activities for the proposed 2013 program will start in July 2012.
Each student pursued a research project guided by a staff astronomer as a mentor. The REU Site
Director and Student Coordinator solicited volunteers among the CTIO, Gemini Observatory, and
SOAR Observatory scientific staff, looking for people who were willing to invest their time and
expertise to work with a student and who had projects suitable for undergraduate students carrying
out research in a 10-week program. As in previous years, there were more than enough volunteers
and projects. This year four REU mentors were CTIO staff members; SOAR and Gemini Scientists
mentored the remaining two students. In addition, one CTIO staff member and one Gemini staff
member served as mentors for the CTIO Práctica de Investigaciónes en Astronomía (PIA) program,
a CTIO-funded program for Chilean students, which is run concurrently with the CTIO REU
program.
1.1.2 Science Program
An essential component of the CTIO REU program is the opportunity students have for interaction
with scientists, not only with the observatory staff, but also with the flow of visiting astronomers
who pass through on their way to the observatory. The generally informal atmosphere at CTIO
provides a climate that promotes these interactions, which take place naturally at “Staff Tea” (every
Friday morning at 11 am the CTIO and SOAR scientific staff gather to discuss science, observatory
matters, and other topics of interest), at regular scientific colloquia, and in the public computer area
that the students share with visiting astronomers and other interns. Informal meetings with various
CTIO staff members and visiting astronomers while students were on the mountain typically
resulted in an on-the-spot introduction to an instrument or research specialty. This year during the
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REU observing run on the 1.0-m telescope, two of the students and the REU Student Coordinator
met one of the world’s experts in exoplanets, Dr. Debra Fischer, while having dinner in the Cerro
Tololo cafeteria. This chance encounter led to a student seminar on the search for exoplanets by Dr.
Fischer when she returned to La Serena after her observing run.
Research Projects
The students’ primary focus while in Chile was to work on their individual research projects,
supervised by their respective scientific mentors, the REU Site Director, and the REU Student
Coordinator. Based on the backgrounds of the students and the suite of available projects proposed,
each student was assigned to a project and mentor that were well-matched to the student’s individual
experience level and research interests. At the end of the program, the students were asked to write a
final report on their project (precursor to a future publication). Abstracts of these papers, written by
the students and their mentors, are included in the “Findings” section. The students were encouraged
to work independently and to develop the skills and expertise to define the direction and scope of
their projects. Students who lacked research experience were given more direct guidance when
necessary. In addition, the REU Student Coordinator was available to any of the students who had
procedural, administrative, or scientific questions. The students attended weekly research group
meetings. At these meetings, the students presented their projects, their progress during the previous
week, and their plans for the upcoming week. These presentations helped them to track their
research progress and discuss issues encountered with their REU peers and mentors. These group
meetings were an excellent way to ensure that substantial and steady progress was made, while at
the same time allowing the students to practice their presentation skills. Over the course of the 10-
week program, their presentations improved dramatically, and their confidence grew equally fast.
At the end of the program, the students presented their work in a mini symposium. Each student
gave a 10–15 minute talk, which was followed by 5 minutes for questions from the audience. The
symposium took place in the AURA auditorium, on the AURA compound in La Serena, and was
attended by the CTIO, Gemini, and SOAR scientific staff and visitors. The REU and PIA students
also will present their work in the form of a poster paper at the 217th meeting of the American
Astronomical Society (AAS), scheduled for 6–10 January 2013 in Long Beach, California.
Participant support costs were provided for the students listed below. The 2012 CTIO REU
Program student research project titles are listed along with the student’s name, university
affiliation, and mentor.
Melissa Butner (Austin Peay State University)
Research Intern to Dr. Eric Mamajek (CTIO)
Project Title: “Spectral Classification of Members of a Candidate Cluster in Telescopium”
Kimberly Emig (University of Hawai’i at Hilo)
Research Intern to Dr. Catherine Kaleida (CTIO)
Project Title: “Simulated Star Clusters with MASSCLEAN: Testing a Stellar Grouping Selection
Method”
Christine Gilfrich (St. Mary’s College of Maryland)
Research Intern to Dr. Tiago Ribeiro (SOAR)
Project Title: “Orbital Period of WD + M Binaries”
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Bezia Laderman (New York University)
Research Intern to Dr. Timothy Abbott (CTIO)
Project Title: “Finding Periodicities CP Eri”
Samuel Meyer (Harvard College)
Research Intern to Dr. Peter Pessev (Gemini)
Project Title: “Expanding Integrated-Light Photometry of LMC Star Clusters in the NIR to
Extremely Young Ages”
Clara Thomann (Macalester College)
Research Intern to Dr. David James (CTIO)
Project Title: “A Photometric and Spectroscopic Survey of Solar-type Stars in Open Cluster
Collinder 70”
Weekly Student Seminars
Apart from the official CTIO colloquia, the students attended a seminar series especially designed to
reflect their needs and interests. The seminars covered a broad range of topics, both observational
(“Intro to Observational Astronomy”) as well as more theoretical (“Tutorial on Adaptive Optics”).
Additionally, several general seminars and discussions were scheduled for the students. For
example, CTIO Director Dr. Chris Smith welcomed the students to Chile with a presentation on
CTIO, NOAO, and AURA, and Deputy Director Dr. Nicole van der Bliek gave an introduction to
life in La Serena. The seminars were given from 16 January through 22 March 2012 by the CTIO
and Gemini scientific staff—and one by visiting astronomer Dr. Fischer—once a week, usually on
Mondays from 2:00–3:00 pm The list of topics and speakers from the 2012 Student Seminar Series
follows below:
Dr. Chris Smith (CTIO Director): “Welcome to CTIO”
Dr. Nicole van der Bliek (CTIO Deputy Director): “Welcome to Chile”
Dr. Alistair Walker (CTIO): ”RR Lyrae Stars”
Dr. Karianne Holhjem (SOAR): “Image Reduction”
Dr. David James (CTIO): “Intro to Observational Astronomy”
Dr. Debra Fischer (Yale University): “Searching for Earths around Alpha Centauri”
Owen Boberg (New Mexico State Univ./CTIO): “Creating Color Images: Making Astronomy
Pretty”
Dr. Malcolm Smith (CTIO): “The UNESCO World Heritage ‘Windows to the Universe’: A
Multidisciplinary Concept to Help Control Light Pollution”
Dr. Andrei Tokovinin (CTIO): “Challenges of Multiple Stars”
Dr. Andrei Tokovinin (CTIO): “Tutorial on Adaptive Optics at CTIO”
Dr. Mischa Schirmer (Gemini): “Data Reduction with Theli”
Dr. Peter Pessev (Gemini): “Gemini Observatory”
Guillermo Cabrera (Universidad de Chile/LSST): “Astroinformatics”
Dr. Catherine Kaleida (CTIO): “Applying for Graduate School”
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Observing on Cerro Tololo
As part of the CTIO REU program, the students observed on Cerro Tololo using the SMARTS
Consortium 1.0-m telescope (Figure 1). The objective of the observing run was to introduce the
students to observing techniques and allow them to sample different methods of observing. The
observing time, eight nights in total, was requested via the regular NOAO Time Allocation
procedure (program ID: 2012A-0594). This proposal was ranked highly by the Telescope Allocation
Committee, receiving a grade of 9 out of 10, where 10 was the highest grade achievable. These eight
nights corresponded to two observing nights for each group of two students.
For the 2012 program, the student observing plan included observations of RR Lyrae variable
stars and Lyman Alpha Blob (LAB) candidates (objects important to understanding galaxy
evolution), in collaboration with Dr. Andrew Layden and Tyler Anderson of Bowling Green State
University, and Dr. Rolf Jansen and Paul Hegel of Arizona State University, respectively. A portion
of the observing time was also left open for the students to observe objects of their own choosing.
The students imaged Southern Hemisphere galaxies, star clusters, and nebulae, as well as confirming
a supernovae candidate (published in an online supernova circular at:
http://www.cbat.eps.harvard.edu/iau/cbet/003000/CBET003014.txt).
Figure 1: Group photo of the 2012 CTIO REU/PIA program students with Cerro Tololo in the background taken from Cerro Pachón. From left to right: Melissa Butner, Kimberly Emig, Samuel Meyer, Catherine Kaleida (REU Student Coordinator), Christine Gilfrich, Mayte Alfaro (PIA student), Bezia Laderman, Odette Toloza (PIA student), and Clara Thomann. Photo by Peter Pessev (Gemini).
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Observatory Field Trips
The REU grant provides funding for a three-day field trip to a site of astronomical significance,
which allows the students to get a taste of other observatories and get acquainted with their unique
telescopes, instruments, and operations. For the 2012 CTIO REU program, the students visited
observatories on Cerro Paranal, Cerro Pachón, Cerro Las Campanas, and Cerro La Silla.
Cerro Paranal is the site of the European Southern Observatory (ESO), one of the premier
astronomical sites in the world, and home to the Very Large Telescope (VLT). The VLT is an array
of four 8.2-m telescopes that operate either as stand-alone telescopes or combined through an
interferometric network to act as one large aperture. The observatory is a three-hour drive from
Antofagasta in Northern Chile, through some of the most arid (and beautiful!) terrain on Earth.
While at Cerro Paranal, the students toured the telescopes and observatory facilities, and over lunch
they met a former CTIO REU student Dr. Gabriel Brammer (2001 CTIO REU program alumnus).
Dr. Brammer is currently a postdoctoral research fellow at ESO Chile, working at Paranal
Observatory. He shared the story of his journey from being a CTIO REU student to an ESO Fellow,
and told the students how the REU program helped him to get to where he is today.
Cerro Pachón is home to two telescopes: the 8.0-m Gemini Telescope, and the 4.2-m SOAR
Telescope. Proximity to CTIO, both geographic and institutional, allowed for easy arrangement of a
site tour for the 2012 REU students. Dr. Peter Pessev (Gemini) and Dr. Tiago Ribeiro (SOAR) led
exciting tours for the REU/PIA students, the REU Student Coordinator, and one Gemini student,
introducing the various instruments and modes of observing at each telescope (Figure 2).
Figure 2: The 2012 CTIO REU/PIA program students in front of the Gemini 8-m mirror. From left to right, front row: Felipe Et (Gemini student), Bezia Laderman, Samuel Meyer; back row: Odette Toloza (PIA student), Mayte Alfaro (PIA student), Clara Thomann, Kimberly Emig, Melissa Butner, Catherine Kaleida (REU Student Coordinator), and Christine Gilfrich.
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This year’s REU and PIA students were very interested to see as many of the major
observatories in Chile as possible during their time here. Thus, the REU Student Coordinator also
arranged for tours of the observatory facilities on Cerro Las Campanas (Las Campanas Observatory)
and Cerro La Silla (ESO’s La Silla Observatory) with sack lunches and transportation paid for by
the students. As La Silla and Las Campanas are relatively near (~2 hours driving) La Serena, this
was an affordable expense and seven of the eight REU/PIA students chose to attend.
Through visiting many different observatories, the students were able to learn about the various
types of telescope designs and their benefits and detriments.
Other Field Trips
Maintaining dark skies for astronomical research and for the general public is an important issue for
future astronomers, as the increase of inefficient lighting and light-emitting diode (LED) billboards
threatens the night skies more every year. To illustrate this point, the students visited the summit of
Cerro Grande, the highest peak near the city of La Serena. On Cerro Grande, they measured the light
pollution from the city, and they honed their astrophotography skills under the guidance of Dr.
Malcolm Smith (CTIO). Using a Sky Quality Meter, they measured the sky brightness and
quantified the difference between the sky brightness in the direction of La Serena and the opposite
direction. Former CTIO Director Dr. Malcolm Smith is a skilled amateur astrophotographer, and he
taught the students how best to use their cameras to capture images of the night sky. The students
took many beautiful shots of the southern sky that evening (Figure 3).
During their time in Chile, the students visited two universities in the La Serena/Coquimbo area:
Universidad de La Serena (ULS), and Universidad Católica de Norte. The purpose of these visits
was to facilitate more interactions between the US students and Chilean students and professors, as
Figure 3: From atop Cerro Grande, REU/PIA students observe the planet Venus and measure the light pollution from the cities of La Serena and Coquimbo. Photo by REU student Clara Thomann.
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well as to supplement their cultural and environmental education while in Chile. Mayte Alfaro, a
2012 CTIO PIA participant and ULS student, arranged a meeting with the astrophysics research
group at ULS. The students learned about the research being conducted at the university and
attended an astronomy seminar, “Stars Outside Galaxies,” by Dr. Sergio Torres Flores.
The REU/PIA students also paid a visit to the Marina Biology department at the Universidad
Católica de Norte in Coquimbo, a neighboring city to La Serena. At the Marine Biology department,
Professor Martin Thiel introduced the group to the “stars of the sea,” giving everyone a tour of the
fish and marine life research facilities and the university’s public aquarium. The students then rolled
up their pant legs and explored the rocky coastline next to the university, using the knowledge they
had just gained to find and identify the organisms. In return, Professor Thiel and his Marine Biology
students were invited to the La Cancha Summer Star Party, organized by CTIO, to see the stars in
the sky. The students enjoyed this exchange tremendously, and there will be a similar visit with next
year’s students.
1.1.3 Student Activities & Local Arrangements
The six US REU students, together with the two Chilean PIA students, shared a fully furnished
house on CTIO’s La Serena compound, for which they were charged a modest rent. This
arrangement maximized the cross-cultural interaction for all of them. The students have consistently
rated this cultural component of the CTIO REU/PIA program to be a successful and important part
of their overall experience. The students were provided with a workspace and a computer in the
public computer area of CTIO’s La Serena facility. Each student had a reserved place in the
computer room and was guaranteed access to a computer previously purchased through this REU
grant. The use of the public computer room promoted the opportunity to interact with visiting
astronomers, several of the technical staff, and other interns. As a result, the students were well
integrated in the daily work and social activities of the Observatory.
The REU and PIA students and the REU/PIA program in general received excellent
administrative support from the staff in Chile and the NOAO Central Administrative Services (CAS)
staff in Tucson. The students encountered no problems with the logistical arrangements during their
time in La Serena.
Program Travel
For travel to/from Chile, and for the domestic flight to Antofagasta for the trip to Cerro Paranal, in-
house personnel were used to coordinate all REU logistics with a local, Chilean travel agency. In the
past, this has proven to be the most reliable and often cheapest option. The on-site availability of this
logistical support enables easy troubleshooting should any problems arise. A travel agent in Tucson
with institutional ties to NOAO was used for 2011 REU student travel to the January 2012 AAS
conference. The travel arrangements for that 2012 AAS meeting were done in a timely and
organized manner, and the plan is to continue this relationship for the 2013 AAS conference and in
the future.
Student travel to Chile this year was subject to a delayed flight in Dallas that resulted in having
to spend the night in hotels in Dallas and Santiago before finally arriving in La Serena. This
situation reconfirmed that it is important that the REU Student Coordinator (who was returning from
the 219th AAS meeting) accompany the REU students on their flight from the US to Chile. The
travel to Chile is often the first international flight for the majority of the students and is an
unfamiliar experience for all of them. Support for transportation and accommodation in La Serena
by local CTIO employees was outstanding.
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1.1.4 Conclusions
After 17 years of successful operations, the CTIO REU program continues to provide a positive
educational experience for all participants, not only in learning about astronomy, but also about the
nature and operation of a national observatory, the future and function of the national and
international astronomy facilities, and how one lives and works in a multicultural setting. Each year,
an evaluation questionnaire is distributed to the REU and PIA students by email. They are asked to
complete the questionnaire and are assured that the results will be considered anonymously. An
online form was created that ensures the anonymity of the students. The main purpose of this
evaluation process is to help determine what parts of the REU program curriculum worked well or
poorly, in order to improve the program in following years. It also provides a measure of the impact
of the program on the students and the degree to which they enjoyed their Chilean REU experience.
When asked, “How do you think the REU/PIA experience has changed you and your outlook on
astronomy and astronomical research?” in the online evaluation, one student answered, “[M]y #1
choice for grad school will be an astrophysics department.” The 2012 program was a positive
educational experience for all of the students, not only in learning about astronomy, but also about
the nature of a national observatory, about the future of the national and international astronomy
facilities, and about how one lives and works in a multicultural setting. The students’ impressions of
the program and their reactions to the experience were extremely positive.
1.2 FINDINGS
At the end of the program, each student presented the results of their 10 weeks of research at a
Student Symposium held in the AURA Lecture Hall on the AURA campus in La Serena. Scientific
staff members of CTIO, SOAR, and Gemini attended this symposium. Each student gave a 10- to
15-minute presentation followed by 5 minutes of questions from the audience. The following are
abstracts of the REU/PIA students’ research projects, written by the students and their mentors:
Melissa Butner: “Spectral Classification of Members of a Candidate Cluster in Telescopium”
We characterize whether the spectral types, colors, magnitudes and astrometry for a sample of
stars in the constellation Telescopium are consistent with constituting a true star cluster. The
candidate cluster was first noticed by E. Mamajek as an excess of A-type stars with similar proper
motions in the HD catalog. Based on the number of A-type stars seen, the candidate cluster could be
surprisingly rich, and hence it would surprising that it had remained undetected until now. We
derived accurate spectral types for these stars using optical spectra from the SMARTS 1.5-m
telescope at Cerro Tololo and comparing them to a grid of MK spectral standards. Our initial
analysis is suggestive that a real group may exist, at distance 400 pc and age 630 Myr (similar to the
Hyades).
Kimberly Emig: “Simulated Star Clusters with MASSCLEAN: Testing a Stellar Grouping
Selection Method”
An accurate selection method for identifying and characterizing stellar groupings in nearby
galaxies is essential for determining the size scales of stellar clustering. By generating fields of
simulated star clusters with known ages, masses, sizes and metallicities, the accuracy of such a
selection algorithm can be analyzed. Using code developed in IDL, the Massive Cluster Evolution
and Analysis Package (MASSCLEAN) and SkyMaker have been used to simulate clusters of
varying ages, masses, and sizes with properties tuned to mimic stellar groupings found in Hubble
Space Telescope, Wide Field Camera 3, and F336W images of the dwarf irregular galaxy NGC
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4214. The point spread function (PSF) has been modeled using Tiny Tim. An archive of simulated
star cluster fields with varying numbers of clusters (∼10–200) and randomly selected positions
within the field has been created. Primarily we examine the number of clusters generated versus the
number retained and discuss the limitations of the selection algorithm in light of these results. A
reliable selection method is imperative for studying the size scales and disruption time of stellar
groupings in nearby galaxies and the relationship between the properties of stellar groupings and
their host galaxies.
Christine Gilfrich: “Orbital Period of WD + M Binaries”
Studying WD + M binaries can give insight into the evolution of cataclysmic variables because
of their presence in CVs’ evolutionary process. SDSSJ0256 is a WD + M binary found in the
SLOAN Digital Sky Survey which has not previously been studied; the SLOAN data does not
include an orbital period. I used spectroscopic data from the Goodman Spectrograph on SOAR
collected at various dates to find the changes in H-α emission lines from the main sequence star
throughout its orbit. From these wavelengths, I calculated the velocities, which were analyzed using
a Lomb-Scargle periodogram to find SDSSJ0256’s orbital period to be 2.6 hours (with a false-
positive probability of 10%), its radial velocity semi-amplitude to be 32 ± 5 km/s, and its gamma
velocity to be 19 ± 4 km/s. We compared this to other possible periods from the Lomb-Scargle
periodogram using their power, false-positive probability as outlined by Frescura et al (2008), and χ2
testing. Although the fit to our data is far from perfect, the phase diagram shows a reasonably close
trend. As such, this study points to an orbital period of approximately 2.6 hours for SDSSJ0256, to
be made more certain by additional observations.
Bezia Laderman: “Finding Periodicities CP Eri”
Between January 27 and January 29 the IBWD (interacting binary white dwarf) CP Eri was
observed from the CTIO 0.9m during a period of quiescence. The data was reduced, light curves
were created by comparing CP Eri to other non-variable stars in the field, and periodograms where
generated from the light curves. An unexpected signal corresponding to a 32-minute periodicity was
found, but the expected signal from previous studies at about 29 minutes was not seen, prompting
the need for follow up observations during periods of quiescence.
Samuel Meyer: “Expanding Integrated-Light Photometry of LMC Star Clusters in the NIR to
Extremely Young Ages”
The goal of this project is to extend the sample of LMC clusters with integrated-light
photometry available to the limits set by the depth of the 2MASS Atlas Images. Using recently
published new catalogs of Magellanic Clouds clusters ages, we are focusing mainly on the clusters
populating the parameter space between 250 and 800 Myr. Such clusters are severely under-
represented in the samples available so far. There are two main reasons for this: (i) samples so far
were focused on clusters with reliable age and metallicity determinations; (ii) the masses (hence
luminosities) of the Magellanic Clouds clusters are decreasing with decreasing age. Clusters
younger than ~1 Gyr are much more challenging from an observational point of view and more
difficult for analysis. To tackle the problem we are adopting a statistical approach, analyzing
hundreds of objects populating the selected age interval. Our data reduction and analysis were
focused on obtaining reliable integrated-light magnitudes and error estimates in J, H, and Ks
2MASS filters. The final sample consisted of 30 objects, effectively tripling the number of objects
with integrated-light measurements available in this age interval. The depth of the imaging data
turned out to be the main limitation. We found that particular care needed to be taken in order to
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mitigate the effects of the stochastic fluctuations in the stellar population. The results of the present
study are crucial for our understanding of the LMC star clusters system. They are paving the road
for the deeper Magellanic Clouds surveys that are going to be available in the future. Considering
that the Magellanic Clouds are invaluable astrophysical laboratory affecting many fields of the
modern astronomy, surely this new dataset will play an important role beyond its original purpose.
We are also considering expanding the dataset using dedicated observations in the future.
Clara Thomann: “A Photometric and Spectroscopic Survey of Solar-type Stars in Open Cluster
Collinder 70”
Presented in this review are preliminary results regarding cluster membership and age via
photometry and fiber spectroscopy observations of 70 low-mass stars in open cluster Collinder 70.
The targets were originally selected from color-magnitude diagrams, and subsequently refined by
using low-resolution spectroscopy to determine the presence of H-alpha and Li I. The members of
Collinder 70 were finalized by a measurement of lithium equivalent widths via Gaussian fitting and
direct integration, concluding with a list of 23 probable members. Model isochrones from Baraffe et
al. (2002) evolutionary models are overlaid on a lithium equivalent width and color plot with target
stars, suggesting that Collinder 70 is less than 50 million years old. Other lines of evidence—low
mass stars with un-depleted levels of lithium, indications of giant-like pre-main sequence stars, and
infrared excess—indicate that the cluster is younger, but the age cannot be constrained without
further observations and more lithium-rich members.
1.3 TRAINING AND DEVELOPMENT
The main goal of the CTIO REU program is to provide an opportunity for students to carry out a
research project, supervised by one of the staff astronomers at CTIO, SOAR, or Gemini and by the
REU Student Coordinator. At the end of the program, the students report on their work in the form
of a written report and short presentation. The students were encouraged to work independently, but
those who lacked research experience were given more direct guidance when necessary by their
mentor or the REU Student Coordinator. The CTIO summer students also had the opportunity to
observe on Cerro Tololo, using the CTIO/SMARTS 1.0-m telescope. The objective of the observing
run was to introduce the students to observing techniques and to allow them to sample different
methods of observing, as dictated by various projects that had different scientific objectives. Thus,
the students experienced the three main tasks of a professional observational astronomer:
observation, analysis of results, and subsequent reporting and publication.
Furthermore, the student selection committee aims to select not only the best students, but also
the students who will benefit the most from the CTIO REU program. For example, the committee
ensures that the students come from a mix of large and small astronomy departments. In addition,
the students are selected to have a wide range of abilities and experience to encourage peer
mentoring. The students obtain teaching skills from answering one another’s questions in their area
of expertise (i.e., computing, telescope operations, etc.), and they gain useful tools and information
from the knowledge of their fellow students.
1.4 OUTREACH ACTIVITIES
One of the highlights of this year’s program was the students’ participation in the Summer Star Party
organized by the Education and Public Outreach (EPO) team at CTIO. The Summer Star Party is a
free event offering sky tours of the night sky, viewing of astronomical objects with small telescopes,
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and astronomy-related activities for children. The Star Party is open to the families and friends of all
observatory staff members (including custodians, human resource staff, mechanical shop employees,
etc.). It is held at a dark-sky site called “La Cancha” that is along the road to Cerro Tololo and Cerro
Pachón and away from the city lights of La Serena. The telescopes on Cerro Tololo are clearly
visible from the La Cancha site, and provide a spectacular setting to observe the Southern skies. The
students were each given a small telescope, called a Galileoscope, which they assembled themselves
and learned to use in a mini-workshop given by the EPO team a few days before the event. With
these Galileoscopes, the students assisted the CTIO EPO team with showing stars, planets, and star
clusters to the attendees of the event. At the end of the event, the students experimented with the
night photography skills they obtained while on Cerro Grande and posed for a photo taken by a
fellow Star Party participant, Hérnan Stockebrand (Figure 4).
2 JOURNAL PUBLICATIONS
Over 100 publications have resulted from collaborations with the REU students since the beginning
of the CTIO program in 1995. An updated list of publications is available at a webpage on the REU
CTIO website (http://www.ctio.noao.edu/noao/content/publications-related-ctio-reu-projects). The
following is a list of recent publications by CTIO REU students. These include publications by the
2011 REU cohorts. The 2012 REU students will present their work at the January 2013 meeting of
the AAS. Students’ names are in boldface text.
Figure 4: The CTIO REU and PIA students pose for a photo with the night sky above Cerro Tololo after participating in a Star Party event for the observatory families and friends at the La Cancha site. From left to right, front row: Bezia Laderman, Catherine Kaleida (REU Student Coordinator), and Clara Thomann; back row: Samuel Meyer, Melissa Butner, Christine Gilfrich, Odette Toloza (PIA student), Mayte Alfaro (PIA student), and Felipe Et (Gemini student). Photo by Hernán Stockebrand.
CTIO REU Award AST-1062976
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Accetta, K. & Kunder, A. 2011, BAAS, 43, #150.01, “RR Lyrae as Structural Tracers for the
LMC”
Banados, E., Hung, L.W., De Propris, R., West, M. 2011, BAAS, 43, #149.17, “The Faint End
of the Galaxy Luminosity Function in A1689: A steep Red Faint End Upturn at z = 0.18”
Basarab, B. 2012, BAAS, 44, #145.04, “The Lick Index Calibration of the Gemini Multi-
Object Spectrographs”
Carney, M.T. 2011, BAAS, 43, #338.03, “Phase-Resolved Cyclotron Spectroscopy and
Polarimetry of HU Aquarii”
Gifford, D., Miller, C., Harrison, C., Kao, M. 2011, BAAS, 43, #408.16, “The Caustic Mass—
Optical Richness Relation for C4 Galaxy Clusters”
Goldwell, G., Salois, A., Soechting, I., Smith, M. 2011, BAAS, 43, #335.29, “Sampling Studies
of Quasars, Radio-loud Galaxies, & Radio-quiet Galaxies—Searching for the Cause of Radio
Emission”
Hung, L.W., Banados, E., de Propris, R., West, M. J. 2011, BAAS, 43, #149.02, “The Galaxy
Alignment Effect in Abel l 1689”
Kao, M., Harrison, C. 2011, BAAS, 43, #149.16, “Caustic Mass Estimate of Abel l 370”
Sayres, C.C., Subasavage, J.P., Bergeron, P., Davenport, J.R.A., AlSayyad, Y., and Tofflemire,
B. M. 2012 AJ, 143,103, “A Multi-survey Approach to White Dwarf Discovery”
Sayres, C.C., Subasavage, J.P., Bergeron, P., Davenport, J.R.A., AlSayyad, Y. 2011, BAAS,
43, #341.01, “Multi-survey and LDA Techniques for Cool White Dwarf Discovery”
3 WEB/INTERNET SITE
The CTIO REU Program website can be found at http://www.ctio.noao.edu/REU/reu.html. On this
website, potential students can find information about the program, and current and past students can
post the results of the research they worked on while at CTIO. The website also contains a page that
lists the publications related to work carried out during the CTIO REU summer student programs,
going back to the start of the CTIO REU program in 1995. Furthermore, the website has various
photo-galleries, which give a good impression of the programs, and the start of an English-Spanish
Astronomy Dictionary, developed by the 2012 REU/PIA group.
4 OTHER SPECIFIC PRODUCTS
As part of the Weekly Research Meeting, the REU and PIA students participated in an Astronomy
Language Exchange. At the beginning of each meeting the students came up with astronomy-related
technical terms in English to translate to Spanish, and from these suggestions compiled the
beginnings of an English-Spanish Astronomy Dictionary. The intent is to continue this practice in
future year’s REU and PIA programs with the aim of creating a comprehensive English-Spanish
Astronomy Dictionary to post on the Web for public use.
FY12 Annual Project Report (Yr 1)
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5 CONTRIBUTIONS
5.1 CONTRIBUTIONS WITHIN DISCIPLINE
The main goal of this program is to allow students, mainly astronomy and physics majors, but also
the occasional math major, to participate in research, get hands-on experience in observing, work in
a research institute (non-university based, for a different perspective), experience the international
nature of astronomy (working in Chile, at an international observatory) alongside Chilean students.
The students directly contribute to making new discoveries in the field of astronomy and frequently
publish these results in peer-reviewed journals. A summary of the specific astronomical discoveries
of the 2012 REU students can be found in the “Findings” section of this document.
5.2 CONTRIBUTIONS TO HUMAN RESOURCE DEVELOPMENT
The goal of this program is the development of young astronomers who will be the future scientists.
Seventeen applications for the 2012 CTIO REU program were received. Of these applicants, 71%
(12 out of 17) were women and 29% (5 out of 17) were men. As the majority of our applicants were
women, 67% (4 out of 6) of the students selected for the 2012 program were women and 33% (2 out
of 6) were men. As this year’s applicants were not asked to disclose their race/ethnicity, there can be
no report on the racial diversity of the applicant pool.
Of the six selected students, five where White/Caucasian (not Hispanic/Latino) and one was
White/Caucasian and Hispanic/Latino (note that as of the 2010 US Census, Hispanic/Latino is no
longer considered a race, but continues to be a group underrepresented in the sciences (for more
information, see http://2010.census.gov/2010census/about/interactive-form.php, and
http://www.nap.edu/catalog.php?record_id=12984). Clearly, the underrepresentation of minorities
in the sciences is reflected in the 2012 REU cohort. We will continue our efforts to advertise heavily
at historically minority-serving institutions and conferences in the US. One of the 2012 students,
Kimberly Emig, will be presenting her project from the CTIO REU program at the National
Conference of the Society for Advancement of Chicanos and Native Americans in Science in
October 2012, and there is hope that other students at this conference will be inspired to apply after
seeing her work and hearing her enthusiasm for the CTIO REU program.
Geographically, the applicants were from 13 states in the US: 6 from the South, 3 from the
Midwest, 2 from the Northeast, 1 from the West, and 1 from the Pacific (Hawai’i). In past years,
there has been a smaller proportion of applicants from the South and Midwest, and it is gratifying to
see that this year the advertising efforts for the program are reaching those parts of the country that
have been underrepresented in our program alumni.
The home institution size of the accepted applicants also was tabulated: 83% (5 out of 6) were
from schools with fewer than 10,000 enrolled undergraduates. The CTIO REU program continues to
be committed to providing astronomy research experiences to students whose home institutions
cannot provide them with the same opportunity.
The CTIO REU groups are chosen based on merit as well as how much they will benefit from
the program, however, an effort is made to have groups that are balanced in gender and include
students from underrepresented minorities. As such, the CTIO REU program is directly contributing
to broadening participation in the science, technology, engineering, and mathematics (STEM)
disciplines.
CTIO REU Award AST-1062976
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5.3 CONTRIBUTIONS TO RESOURCES FOR RESEARCH AND EDUCATION
The 10-week REU program includes lectures by observatory staff who cover a range of topics. The
students visit neighboring observatories (SOAR and Gemini South) as well as the more northern
observatories (Las Campanas and ESO with the La Silla Observatory site and the Paranal
Observatory site).
5.4 CONTRIBUTIONS BEYOND SCIENCE AND ENGINEERING
One of the unique characteristics of the CTIO REU program is that it offers the opportunity to live
and work in an international setting at an observatory in a foreign country. The US students work
alongside Chilean students who participate in the parallel PIA program, and the cultural experience
these young astronomers obtain is as invaluable to their growth and maturation into successful
astronomers as the research projects themselves. When asked in the program evaluation to give
advice to future year’s students, one 2012 REU student stated, “…be prepared to learn things you
didn’t expect. I would say that I learned more about myself and how interact with others.”
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