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Subject Category: ACTIVE GALAXIES AND QUASARS

Proposal Title: THE AGN CONTENT OF GALAXY CLUSTERS

PI Name: PAUL MARTINI

The space density of AGN and starburst galaxies declines precipitously from z = 2 to the present day. The si milar evolution of these two populations, and their common requirements of a ready fuel source and angular momentum loss, suggest a coupled evolution. In clusters of galaxies, the starburst population is known to decline significant ly from z = 0.5 to the present. If the same physical processes give rise to AGN and starbursts, there should be a si milar decline in the cluster AGN fraction. We propose to test this scenario with archival Chandra observations of el even, well-studied galaxy clusters to determine the AGN fraction of these clusters and to determine if their space d ensity declines in step with the fraction of starburst galaxies.

Subject Category: CLUSTERS OF GALAXIES

Proposal Title: A CHANDRA ARCHIVAL STUDY OF GALAXY GROUPS

PI Name: JOHN MULCHAEY

We propose to perform a uniform analysis of a sample of 28 galaxy groups observed with the ACIS cameras. The archival Chandra data will be used to: 1) model the complex surface brightness profiles of groups, 2) measure tempe rature and metallicity profiles for the diffuse gas, 3) determine the Lx-T and Lx-sigma relationships for groups and 4) search for structure in the gas morphologies. The high spatial resolution of Chandra is required to separate the emission from the central galaxy from the more extended group component. The Chandra data will allow us to derive d etailed mass, dark matter and baryon profiles for groups, probe the origin of the gas and test currently-favored pre heating models.

Subject Category: CLUSTERS OF GALAXIES

Proposal Title: THE STRUCTURE OF GALAXY CLUSTERS AND THE NATURE OF DARK MATTER

PI Name: JOHN ARABADJIS

We propose to assemble a large sample of relaxed galaxy clusters from the Chandra archive to examine their s tructural properties for clues to the nature of their constituent dark matter particles. Using a deprojection and mo delling technique that we have applied to the cluster MS1358, we will derive baryon temperature and density, and tot al mass profiles for the sample, and measure (or place upper limits upon) the size of any constant density. Using la rge numerical simulations as a calibrator, we will constrain the scattering cross section of the constituent dark ma tter particles. The uniformly derived set of profiles will allow us to examine the sample for evidence of evolution in many structural parameters, and interpret the results in the context of large scale structure formation.

Subject Category: CLUSTERS OF GALAXIES

Proposal Title: A PUBLIC LIBRARY OF INTRACLUSTER MEDIUM (ICM) ENTROPY DISTRIBUTIONS

PI Name: MEGAN DONAHUE

The entropy distribution of the ICM is its most fundamental property. That distribution, along with the dark -matter potential, determines both the density and temperature profile of a relaxed cluster. Because cluster propert ies do not conform to self-similar scaling relations, some combination of radiative cooling, supernova feedback, and AGN feedback must have modified the entropy distributions of clusters at an early time. In order to identify the ph ysical effects that caused this similarity breaking, we propose to construct a library of entropy distributions deri ved from Chandra cluster data. These entropy distributions will provide an ideal testbed for evaluating theories of how radiative cooling and energy injection determine the properties of present-day clusters.

Subject Category: CLUSTERS OF GALAXIES

Proposal Title: JOINT X-RAY AND SUNYAEV-ZEL'DOVICH EFFECT ANALYSIS OF Z>0.8 GALAXY CLUSTERS

PI Name: ERIK REESE

We propose to perform a joint analysis of archival Chandra X-ray data and Sunyaev-Zeldovich Effect (SZE) dat a to obtain improved measurements of the mass, density, and distance of the high redshift galaxy clusters MS 1054.5- 0321 and ClJ0152.7-1357. These objects are cosmologically significant because they are among the most massive and mo st distant clusters known, and their existence provides strong constraints on structure formation models. Chandra X- ray data will significantly improve our knowledge of the temperature and spatial distribution of the gas in these cl usters and in combination with the SZE data, will allow us to a) determine accurately the gas mass and total mass of each cluster, b) place significant constraints on Omega_M, and c) determine distances to these clusters.

Subject Category: CLUSTERS OF GALAXIES

Proposal Title: THE HIFLUGCS / CHANDRA ARCHIVE CLUSTER SURVEY: A CORNERSTONE FOR COSMOLOGY

PI Name: CRAIG SARAZIN

Statistical studies of galaxy clusters yield tight constraints on cosmological parameters, the formation of large scale structure, and the nature of dark matter/energy. Dominant sources of uncertainty today are systematic ef fects, affecting flux, gas temperature, and mass measurements. We propose a detailed systematic investigation of pro cesses in the very cluster centers requiring Chandra and a complete statistical sample of bright nearby clusters. HI FLUGCS is the best currently available local cluster sample in terms of homogeneous X-ray selection based on the ROS AT All-Sky Survey, completeness, size, and availability of a large fraction of high quality observations. Analyzing the Chandra observations for this sample we will constrain the density of the universe to competitive accuracy.

Subject Category: EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS

Proposal Title: SPATIAL FLUCTUATIONS AND PROBING Z~5 UNIVERSE IN THE CHANDRA DEEP FIELDS

PI Name: TAKAMITSU MIYAJI

In this Chandra archival research proposal, we request fundings for a number of unique analysis involving th e Chandra Deep Fields that we are conducting. One is the extension and refinement of the fluctuation analysis, which we have used to constrain Log N-Log S curve a down to a factor of several fainter than the source detection limit. Using our image simulator, we will further pursue angular cross-correlation function of X-ray image with various gal axy catalogs. Finally, we search for X-ray emission associated with z~5 galaxies, whcih have recently been obtained by Suprime Cam attached to SUBARU telescope, through stacking and angular cross-correlation analysis as well as sour ce identifications.

Subject Category: EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS

Proposal Title: THE CHANDRA MULTI-WAVELENGTH PROJECT (CHAMP): A SERENDIPITOUS X-RAY SURVEY WITH CHANDRA ARCHIVAL DATA

PI Name: PAUL GREEN

We are performing a serendipitous X-ray survey (ChaMP) of ~14 sq deg of sky 10-100 times deeper than pre-Cha ndra surveys, but 70 times wider than the Chandra deep surveys. We predict 4000 sources, of which ~3000 are active g alaxies. Optical imaging is in progress, to flux limits matched to the X-ray data using SDSS g',r',i' filters. The C haMP 1) requires no new X-ray observations 2) covers enough area to find sources at brighter fluxes not well-sampled by Chandra deep surveys 3) provides a large, uniform, multi-wavelength public database allowing the community to ad dress a wide variety of scientific questions. We request continued funding to extend our specialized X-ray analysis pipeline, to produce and publicly release source lists, and to support our ground-based followup observations.

Subject Category: GALACTIC DIFFUSE EMISSION AND SURVEYS

Proposal Title: THE NATURE OF DIFFUSE X-RAY EMISSION IN THE GALACTIC PLANE

PI Name: FARHAD YUSEF-ZADEH

Using Chandra's recently archived data of the inner 0.8x2 degrees of the Galactic center and the Scutum arm region, we intend to map the distribution of diffuse 6.4 keV and continuum X-ray emission using a novel technique de veloped for mapping of spectral features. The comparison of diffuse X-ray emission from these two regions will addre ss the nature of X-ray emission from the Galactic ridge. In particular, we intend to test if impact ionization by lo w energy cosmic ray electrons can be responsible for the production of diffuse X-ray emission in the Galactic plane.

Subject Category: NORMAL GALAXIES

Proposal Title: ANALYSIS OF THE RPS97 GALAXY SAMPLE: DIFFUSE EMISSION

PI Name: ERIC SCHLEGEL

We propose to analyze thirteen of the seventeen galaxies in the Read-Ponman-Sutherland (1997) ROSAT sample o f galaxies. The analysis will be uniform, using the most recent reprocessed data for the galaxies as well as up-to-d ate calibrations. Our analysis will separate the discrete and diffuse emission more cleanly than was possible by RPS 97, thereby yielding a more accurate description of the diffuse emission. Hardness maps will contrast X-ray morpholo gy to optical, 2MASS, and radio morphology. For the more luminous ISMs, we will extract X-ray spectra to search for line emission and measure the temperatures to test whether the temperatures of `coronal' and `wind' galaxies differ.

Subject Category: NORMAL GALAXIES

Proposal Title: THE X-RAY SOURCE POPULATION IN THE LATE-TYPE SPIRALS NGC 1637 AND NGC 3877

PI Name: STEFAN IMMLER

Deep Chandra ACIS-S observations of NGC 1637 (215 ks) and NGC 3877 (122 ks) are available in the Chandra Dat a Archive as a result of coordinated multi-epoch and multi-wavelength observations of supernovae 1999em and 1998S. T he data allow an unprecedented in-depth study of the characteristics and nature of the X-ray point source population and diffuse emission in late-type spiral galaxies. Combined with HST, HI and radio continuum data obtained during t he same period as the Chandra data, this unique data set is perfectly suited to obtain a multi-wavelength perspectiv e on the high-energy properties in nearby galaxies and establish links to the star-formation rate history for galaxi es of different types.

Subject Category: NORMAL GALAXIES

Proposal Title: COOLING DISKS IN ELLIPTICAL GALAXIES: THE ROLE OF ANGULAR MOMENTUM IN THE HOT ISM

PI Name: THOMAS STATLER

It has long been hoped that X-ray observations of elliptical galaxies could yield accurate mass profiles, av oiding the mass-anisotropy degeneracy of stellar dynamics. But growing evidence for shocks and bubbles, and the stro ng case for a rotationally flattened disk in NGC 1700, cast doubt on the assumption that these are simple, hydrostat ic systems. Moderate rotational support in the hot gas may be widespread, though difficult to detect. This proposal describes a plan to assess this possibility. Archival ACIS data for roughly 30 ellipticals will be reanalyzed to obt ain photometric profiles of the diffuse emission. These will be combined with optical data and theoretical models to determine whether the distribution of X-ray and optical ellipticities is affected by rotation of the gas.

Subject Category: NORMAL GALAXIES

Proposal Title: A HIGH RESOLUTION, MULTI-WAVELENGTH SURVEY OF NEARBY GALAXIES: X-RAY OBSERVATIONS

PI Name: CHRISTINA LACEY

A multi-wavelength survey of nearby galaxies is necessary to study the properties of the interstellar medium , to identify supernova remnants and HII regions, and to understand the selection biases that affect each wavelength regime. One of the primary goals of this investigation is to construct galaxy-wide samples of SNRs with which to st udy the interstellar medium (ISM), star formation, remnant evolution, the effects of the remnants on the ISM, and pr operties of cosmic ray acceleration. We propose to use archive observations of NGC 6946 and NGC 4449 and compare the X-ray data with Very Large Array 6 and 20 cm data and optical data (imaging and spectroscopy) to pursue our goal of understanding how SNRs evolve and affect the evolution of galaxies.

Subject Category: NORMAL GALAXIES

Proposal Title: GLOBULAR CLUSTER X-RAY SOURCES IN LATE-TYPE GALAXIES: II. ARCHIVAL INVESTIGATION

PI Name: MICHAEL LOEWENSTEIN

Previous Chandra observations have uncovered surprisingly rich and diverse populations of X-ray sources -- i ncluding possible black hole candidates -- associated with globular clusters (GCs) in M31 and in several early-type galaxies. Little is known, in general, about the X-ray properties of GCs in spiral galaxies and of sources fainter t han $10^{37}$ erg/sec. We propose to study all spiral galaxies in the Chandra archive for which sources are identifi able with optical globular clusters in HST fields. A companion proposal aims to add to this database with a carefull y selected sample of new observations. These studies sheds light on mechanisms of X-ray binary creation and retentio n in GCs, and on the variation of GC properties with galactic setting.

Subject Category: NORMAL GALAXIES

Proposal Title: AN ARCHIVAL STUDY OF THE RELATIONSHIP BETWEEN GLOBULAR CLUSTERS AND LMXBS IN ELLIPTICAL GALAXIES

PI Name: STEVE ZEPF

We propose to combine archival HST and Chandra images of elliptical galaxies to identify and characterize th e relationship between globular clusters and LMXBs. We will create a publicly accessible database of globular cluste rs detected in HST images of 14 ellipticals for which there is Chandra data available. This database will include lu minosities, colors, and effective radii determined for the globular clusters. We will give astrometry matched to the Chandra image, and detailed completeness functions for the HST data. We will use this database to carry out studies of the origin of LMXBs in elliptical galaxies. Specifically, we will determine the fraction of LMXBs found in globu lar clusters, and characterize the properties of those globular clusters that currently host LMXBs.

Subject Category: NORMAL GALAXIES

Proposal Title: LOW MASS X-RAY BINARIES AND GLOBULAR CLUSTERS IN VIRGO AND NON-VIRGO EARLY-TYPE GALAXIES FROM THE CHANDRA AR CHIVE

PI Name: CRAIG SARAZIN

We will analyze archival Chandra observations of early-type galaxies to detect their Low Mass X-ray Binaries (LMXBs). We will determine the luminosities, luminosity function, spectral properties, X-ray colors, and variabilit y of the LMXBs. Many luminous supersoft sources will be detected. LMXBs are our only direct observation of the massi ve stars which once existed in E/S0s. About half of our sample galaxies will be observed as part of the HST ACS Virg o Survey, which will determine their globular cluster (GC) populations. Previous observations have shown that a high fraction of LMXBs in E/S0 galaxies are located in GCs. We will compare the properties of the GC and non-GC LMXBs, w ith the aim to understand the origin of LMXBs, and to constrain the evolution of GCs and E/S0 galaxies.

Subject Category: NORMAL STARS AND WD

Proposal Title: AN ARCHIVAL X-RAY STUDY OF SHOCKED STELLAR WINDS OF WOLF-RAYET STARS

PI Name: MARTIN GUERRERO

Wolf-Rayet (WR) stars are evolved massive stars with strong fast stellar winds. Observations of Galactic WR stars have shown three sources of X-ray emission associated with their winds: shocks in the winds, colliding stellar winds, and wind-blown bubbles. However, quantitative analysis has been hampered by the uncertainties in distance an d absorption. It is not even known whether single WR stars follow the same Lx/Lbol ~ 10^-7 relationship as OB stars. We propose to analyze 103 archival Chandra observations of 54 WR stars in the Magellanic Clouds (MCs) to search for X-ray emission associated with these stars and determine its origin. We are uniquely qualified for the proposed sci ence because our team members have carried out a systematic binarity survey for all MC WR stars.

Subject Category: SN, SNR AND ISOLATED NS

Proposal Title: FINDING X-RAY SUPERNOVA REMNANTS IN NEARBY GALAXIES

PI Name: KNOX LONG

More than 400 SNRs and SNR candidates have been identified in nearby galaxies using optical and radio techni ques. Except for SNRs in the Magellanic Clouds, few of these have been seen as X-ray sources due to the limited sens itivity of earlier X-ray observatories. Nearly all of the galaxies with substantial numbers of SNRs have have been i maged with Chandra. Here we propose to search for X-ray emission at the sites of radio or optically-identified SNRs. Since SNRs are the only known high luminosity (>10**35 erg/s) examples of X-ray sources dominated by thermal plasma emission, we will also search the X-ray images to identify X-ray-only SNRs. We will use the combined sample to expl ore correlations between optical, radio, and X-ray properties of SNRs.

Subject Category: SN, SNR AND ISOLATED NS

Proposal Title: TEMPORAL AND SPECTRAL STUDIES OF THE CENTRAL COMPACT SOURCE OF CASSIOPEIA A

PI Name: SACHIKO TSURUTA

Since the point-like source was discovered near the center of Cassiopeia A (Cas A) in August 1999, Chandra X -Ray Observatory has observed this supernova remnant on numerous occasions. Our initial findings of three of these o bservations indicate that a possible large time scale variablility may exist. Therefore, we propose to carry out tho rough temporal and spectral analysis of all relevant data on Cas A point source in the Chandra Data Archive. Our goa l is to find the true nature of this elusive point source. Our results and subsequent interpretation should potentia lly provide great impacts on the theories of SN explosion, progenitor scenario, compact remnant formation, accretion to compact objects, and neutron star thermal and magnetic evolution.

Subject Category: WD BINARIES AND CV

Proposal Title: CHAMPLANE: ARCHIVAL ANALYSIS AND DATA BASE

PI Name: JONATHAN GRINDLAY

We propose to continue our archival analysis of Chandra observations in the galactic plane (b < 10deg) to ca rry out the Chandra Multiwavelength Plane (ChaMPlane) Survey. Development of additional x-ray processing and data ar chiving tools will be carried out for 15-20 galactic fields to be added to the current partial database of 24 fields . Both x-ray analysis and optical identification, under a NOAO Survey program, promise to yield the first galactic p opulation study of CVs, quiescent LMXBs and coronal emission from stars and produce an accessible database.

Last modified: 12/02/10

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