AMNH Division of Physical Sciences


Division of Physical Sciences RESEARCH EXPERIENCES FOR UNDERGRADUATES Summer 2006 Nominal Dates: May 30 thru August 4, 2006 The AMNH Division of Physical Sciences is pleased to offer summer research opportunities in Astrophysics and Earth and Planetary Science. The program is open to all U.S. students, in any four year undergraduate degree program. Pending funding approval, successful applicants will receive a stipend of $4000. Dormitory housing, or an equivalent housing stipend, will be provided. Based on need, travel costs to and from New York City are also covered. We are now accepting applications for the Summer 2006 Physical Sciences REU program. Review of applications will begin on FEBRUARY 15, 2006. Late applications may be considered, but only until all positions have been filled. The application form for this year's REU program is available here. This is an 80 kb Word document. If you have any problems downloading, viewing, or printing the file, let us know via email right away. The Museum's official REU webpage is connected to this link. Follow these links to learn more about the AMNH Departments of Astrophysics and Earth and Planetary Sciences. Look below, on this page, for some of the research projects that are being offered for this summer's program. Thank you all for your interest! For more information on the Earth and Planetary Science program, contact Dr. James Webster. For more information on the Astrophysics program, contact Dr. Charles Liu.

RESEARCH PROJECTS FOR THE SUMMER 2006 PROGRAM
Investigating Prior Explosive Eruptive Activities at Mt. St. Augustine Volcano, Alaska Advisors: Dr. Jim Webster and Dr. Charles Mandeville Augustine is one of the more than 40 historically active volcanoes of the Aleutian arc that poses a risk to the inhabitants and businesses of southern Alaska. It has undergone 6 violent eruptions in the past 200 years, and has shown increased seismic activity in the past several months. As part of our ongoing research on volcanic rock samples representing explosive eruptions of Augustine during the past 2000 years, we are interested in working with a student on methods of determining the volatile (H2O, CO2, SO2, and Cl) abundances of magmas associated with past eruptive activities. The student will have the opportunity to gain experience in petrography, analytical methodologies including electron microprobe and FTIR, and experimental petrology.
Star Formation In Galaxies Advisor: Dr. Mordecai-Mark Mac Low Galaxies form stars at widely varying rates. Low surface brightness galaxies form stars only 1% as fast as the Milky Way, while starbursts reach hundreds or even thousands of times the rate of the Milky Way. What controls this behavior? We have run high-resolution simulations of galaxies including self-gravitating gas, stars, and dark matter. We have found that gravitational instability in the rotating disk of gas may be a sufficient explanation for the star formation rates. However, our analysis of the simulations to date has not been focused on directly observable quantities. In particular, the initial stability of the disk is different from its observed stability after a period of star formation. An opportunity therefore exists for a student to use the simulations to make predictions of what surveys of real galaxies should see. A particularly energetic student could then compare the results of those surveys to the predictions. This work requires the ability to quickly learn computational details such as file formats and analysis software (probably IDL) running under some Unix variant such as Linux or Mac OS X. Background knowledge about galaxies can be acquired during the course of the project as necessary.
Prehistoric Basaltic Eruptions of Krakatau Advisor: Dr. Charles Mandeville Krakatau Volcano in Indonesia is renowned for its catastrophic eruption in 1883 that killed more than 36,000 people. This volcano has also been the site of pre-historic explosive eruptions of basaltic magmas in addition to those of evolved dacitic and rhyodacitic magmas. Relatively little is known about the pre-eruptive volatile concentrations of these pre-historic basaltic eruptions. Moreover, trace element and volatile concentrations (H2O, CO2, S, Cl, F) measured in these basaltic magmas will provide insights into the mantle melting process that supplies magma to this unique portion of the Indonesian Island Arc. The student will have the opportunity to gain experience in petrography and analytical methods such as FTIR spectroscopy, electron microprobe analysis, and laser ICP-MS.
Stirred but not shaken: stellar collisions and mergers Advisor: Dr. Orsola DeMarco Many stars form as the result of a collision with another star, or an interaction with its own binary companion. These encounters may be responsible for stars such as Blue Stragglers in Globular Clusters, Supernovae Type Ia, as well as scores of evolved short-period binaries, including black holes, neutron stars and white dwarfs. We have been studying different aspects of colliding/interacting stars both with observations from large telescopes and with computer simulations. In summer 2006 there will be datasets to discover whether planetary nebulae (gas spewed out from old stars) are the results of binary interactions. The successful applicant may have an opportunity to join an observing trip to the 4-m telescope at Kitt Peak National Observatory (AZ), where data will be collected. There will also be the possibility of carrying out computer simulations of stellar encounters, for those interested in theoretical work.
Thermal Histories of Unusual Carbonaceous Chondrites Advisor: Dr. Jon Friedrich Carbonaceous chondrites are among the most primitive meteorite samples on Earth and clues about their chemical and thermal histories can be elucidated from the examination of their trace elements. We will use Inductively Coupled Plasma Mass Spectrometry (ICPMS) to analyze the trace element content(s) of a suite of highly unusual metamorphosed carbonaceous chondrites. Comparison of the unusual samples' composition to well-characterized carbonaceous chondrites will help place the samples into a relevant early solar system context. We will attempt to deconvolve the nebular and parent body effects evident in the chemical signatures of the meteorites, to discover more about the processes active during the formation of the solar system and planetary bodies 4.5 billion years ago.
Links Between Stars, Brown Dwarfs, and Giant Planets Advisor: Dr. Kelle Cruz With their relatively recent discovery, we are just beginning to explore the observable properties of low-mass stars and brown dwarfs (star-like objects that are not massive enough to sustain nuclear fusion in their core and thus gradually cool and dim with time). Projects for REU students include reducing and analyzing optical, near-infrared, and/or infrared spectra and photometry of low-mass stars and brown dwarfs. These data can be compared to theoretical models to identify features that reveal properties of the objects such as the dust in the photosphere, its mass, and its chemical composition. The goal is to study these objects in detail in order to find observable differences and similarities between low-mass stars, brown dwarfs, and giant planets.
Star Formation Rates in Dwarf Companion Galaxies Advisor: Dr. Charles Liu Quantifying and understanding the populations of stars in these dwarf companions can provide valuable insights on the processes important to galaxy formation and evolution. One subset of the field galaxy population - large galaxies with no nearby, comparably-luminous companions - is potentially very useful for studying these questions. For this REU project, the student researcher will reduce and analyze optical imaging and spectroscopic data for a small, well-defined sample of isolated field galaxies, to identify the companion galaxies around them, and measure their star formation properties. The goals will be to learn more about the megaparsec-scale environments of isolated field galaxies and to test competing models of galaxy formation.
The Magmas Of Mount Mazama Advisors: Drs. Charles Mandeville and Jim Webster The Explosive Eruption of Mt. Mazama, Crater Lake, Oregon roughly 7700 years ago was the largest in North America in the last 10,000 years. This explosive event had an eruption plume reaching well into the stratosphere resulting in worldwide distribution of H2SO4 aerosol as recorded in polar ice cores. Glassy melt inclusions and apatite crystals in the pumices and scoria provide a record of the pre-eruptive volatiles (H2O,CO2, S, Cl, F) dissolved in Mt. Mazama magmas prior to eruption. The student will investigate the compositions of phenocryst-hosted melt inclusions and of apatite phenocrysts with the electron microprobe and FTIR spectrometer.
Protostellar Outflows in Molecular Clouds Advisor: Dr. Hector Arce As a star forms by gravitational infall, it energetically expels mass in a bipolar jet. The ejected matter can accelerate entrained gas to velocities greater than those of the cloud, thereby creating a molecular outflow. Outflows can drive turbulence their parent molecular clouds, induce changes in the chemical composition of their surrounding environment, and may even contribute to the decline of the infall process by clearing out dense gas surrounding the protostar. In addition, outflows can be useful tools to help understand the underlying formation processes of young stars, as they provide a record of the mass-loss history of the system. The REU project aims to search for outflows in star-forming molecular clouds using millimeter and infrared data, and study how outflows influence their surrounding gaseous medium at different size and density scales.
Evidence for Asteroidal Collisions: Foreign Clasts in Meteorites Advisor: Dr. Jon Friedrich Many chondritic meteorites, the most primitive materials in the solar system, contain fragments of other, chemically distinct, parent bodies within them. These xenolitic breccias are the primarily the result of collisions between different parent asteroids. Through literature searches and collections examination, we will examine the diversity of foreign clasts within chondrites and achondrites. This work will ascertain which parent bodies are the sources of foreign clasts and we will learn more about the processes active during the evolution of the solar system and planetary bodies.
Studying Galaxies with COSMOS Advisors: Drs. Neil Tyson and Charles Liu COSMOS is a major Hubble Space Telescope survey with a massive international multiwavelength followup effort that, when completed, will be applied to a wide variety of astronomical questions. One preliminary study to be conducted, using the first portions of the COSMOS data, will be to identify the strongly star-forming galaxies in the survey and measure their luminosities, positions, and spatial distributions. The eventual goal of such a study would be to measure and understand the changes that have occurred in the field galaxy population as a function of cosmic time.
Radio Galaxies in the COSMOS Field Advisor: Dr. Tim Paglione The Cosmic Evolution Survey (COSMOS) provides not only extensive and sensitive measurements of an enormous number of galaxies, but also investigation of these galaxies at many wavelengths. By going beyond the visible, we probe regions hidden by dust clouds or invisible because of the extreme energies and exotic processes involved. The radio COSMOS catalog will contain over 3500 galaxies including quasars, galaxies with jets millions of lightyears long, supermassive black holes and supernova explosions. The REU student will measure some of the properties of the radio galaxy population including their clustering in space, their association with sources at other wavelengths, or their number at different distances or luminosities.
Petrologic Features Of Enstatite Chondrites Advisor: Dr. Michael Weisberg Chondrites are among the oldest and most primitive materials in the solar system. The enstatite chondrites are particularly interesting because their mineralogy is very different from other chondrites. They have important implications for the evolution of the solar system and formation of the inner planets (Mercury through Mars). They represent an extreme in the solar system conditions that resulted in the properties of chondrites. This project will involve researching the properties of chondrites, examination of thin sections of enstatite chondrites, electron microprobe - X-ray mapping of enstatite chondrites to study the distribution of elements and scanning electron microscopy to identify minerals and study textural relationships. Comparisons will be made between enstatite chondrites of different metamorphic grades to identify the effects of metamorphism and identify the least metamorphosed materials.
Classification and Measurement of Inclusions in the Allende Meteorite Advisor: Dr. Denton Ebel The oldest rocks in the solar system are aggregates of mineral dust, chondrules, and Ca-, Al-rich inclusions (CAIs). The CAIs and chondrules formed as free-floating aggregates of mineral dust. Some CAIs and chondrules were partially or fully melted to form droplets in the solar nebula, even before the oldest meteorites formed. A great many already-cut slabs of the Allende meteorite will be scanned, and the types, abundances, and sizes of CAIs and chondrules will be determined by image analysis. Complementary data will be collected on thin sections using the Petrographic Microscope, Scanning Electron Microscope and Electron Microprobe. This study has direct bearing on the fractionation of elements in the early solar system and the formation of planets. Results will be compared with very limited existing data, with the goal of preparing an abstract for the March 2007 Lunar and Planetary Science Conference.