Chandra X-Ray Observatory
	(CXC)

Cycle 6 Accepted Archive Proposals

Proposal NumberSubject CategoryPI NameTitle
06200114 STARS AND WD Eric FeigelsonChandra Orion Ultradeep Project (COUP)
06200277 STARS AND WD Scott Wolk An Archive of Chandra Observations of Regions of Star Formation (ANCHORS)
06200569 STARS AND WD David Cohen Doppler-Broadened Grating Spectra of Hot Stars: Emission Line Profile Model Fitting
06200825 STARS AND WD Susan Hojnacki Spectral and Temporal Classification of X-ray Sources in Young Stellar Clusters
06300487 WD BINARIES AND CV Marina OrioA comparison of different supersoft X-ray sources
06500246 SN, SNR AND ISOLATED NS George Pavlov Archival Study of Spin-powered Pulsars and Pulsar Wind Nebulae.
06500591 SN, SNR AND ISOLATED NS Kazimierz BorkowskiType Ia SNRs in the Large Magellanic Cloud: an Analysis of Archival Data
06500783 SN, SNR AND ISOLATED NS Lawrence Rudnick The Structural and Radiative Evolution of Cassiopeia A
06500887SN, SNR AND ISOLATED NS Kazimierz Borkowski Spatial Structure of Supernova Ejecta in Cassiopeia A
06500919 SN, SNR AND ISOLATED NS Jessica Warren A Quantitative Study of Clumping in Young Supernova Remnants
06610387 NORMAL GALAXIES: DIFFUSE EMISSION Christine JonesElliptical Galaxies in the Local Universe
06610666 NORMAL GALAXIES: DIFFUSE EMISSION Ewan O'Sullivan Dark Matter in Elliptical Galaxies
06620691 NORMAL GALAXIES: X-RAY POPULATIONS Steve ZepfAn Archival Study of the Origin and Evolution of LMXBs in Elliptical Galaxies
06620842 NORMAL GALAXIES: X-RAY POPULATIONS Ann Hornschemeier X-ray Probes of Star-Formation Using Two Rich Archives: the Combined Power of Chandra and the SDSS
06700184 ACTIVE GALAXIES AND QUASARS Luis Ho The Spectral Energy Distributions of Low-Luminosity AGNs: An Opportunity to Probe New Accretion Physics
06800364 CLUSTERS OF GALAXIES Megan Donahue Are Cluster Simulations Realistic? Observational Benchmarks for the Next Generation Cluster Simulations
06910866 GALACTIC DIFFUSE EMISSION AND SURVEYS Smita Mathur Galactic Corona or Local Group Intergalactic Medium?: An Archival Search
06910867 GALACTIC DIFFUSE EMISSION AND SURVEYS Michael Muno An Archival Analysis of Stellar Life-Cycles at the Galactic Center

Subject Category: STARS AND WD

Proposal Number: 06200114

Title: Chandra Orion Ultradeep Project (COUP)

PI Name: Eric Feigelson

The 10-day Cycle 4 Chandra exposure of the Orion Nebula, now in the public archive, provides the most comprehensive database ever acquired on the X-ray emission of normal stars. With 1616 sources in the COUP image, we detect the full initial mass function and all phases of early stellar evolution. The superb lightcurves show hundreds of magnetic flares. COUP addresses a wide range of issues from the census of Orion cloud stars to the evolution of stellar activity, the physics of magnetic dynamos and flares, magnetic confinement of OB winds, effects of X-ray ionization of cold gas, and gas-to-dust ratio of molecular material. We request here funds to partially support the preparation of 25 planned science papers.


Subject Category: STARS AND WD

Proposal Number: 06200277

Title: An Archive of Chandra Observations of Regions of Star Formation (ANCHORS)

PI Name: Scott Wolk

We propose the creation of a web based archive of Chandra observations of regions of star formation. Chandra sources will be cross-referenced with other multiwavelength archival data and new ground based data. Users throughout the astronomical community will be able to access the archive. A top level filter will allow users to search for source in specific flux, age, mass ranges, etc. We seek funding to allow for support of a uniform source catalog, database development, coronal modeling and ground based observing. We will emphesize code reuse from other Chandra programs including COUP and and the Supernova Remnant Archive. Our goal is to provide a community resource for the analysis of young active stars. Our prototype is online at: http://hea-www.harvard.edu/~swolk/ANCHORS/.


Subject Category: STARS AND WD

Proposal Number: 06200569

Title: Doppler-Broadened Grating Spectra of Hot Stars: Emission Line Profile Model Fitting

PI Name: David Cohen

The broadened and characteristically shaped X-ray emission line profiles from O stars provide unprecedented insight into the kinematics and spatial distribution of the hot plasma on these stars. The quantitative analysis of the emission line profiles therefore provides important constraints on models of wind-shock heating in these massive, hot stars. It also has given us important insight into the ambient wind opacity, with hints that O star winds are much less opaque to X-rays than models predict. We propose to apply the analysis that has thus far been performed on only two Chandra grating spectra to an additional half dozen O stars from the archive.


Subject Category: STARS AND WD

Proposal Number: 06200825

Title: Spectral and Temporal Classification of X-ray Sources in Young Stellar Clusters

PI Name: Susan Hojnacki

The rich archive of CXO observations of young clusters has spawned a vigorous debate concerning the origin of X-ray emission from young stars. We propose to apply and further develop our existing X-ray source clustering algorithm, which groups X-ray sources based on their spectral and temporal properties. It is expected that, through the analysis and clustering on datasets of young stars, we will be closer to answering the question of whether X-rays are derived from coronal activity, accretion, outflow activity, or some combination of these mechanisms. The answer to this question will have an impact on studies of a wide variety of astrophysical phenomena that produce X-ray emission.


Subject Category: WD BINARIES AND CV

Proposal Number: 06300487

Title: A comparison of different supersoft X-ray sources

PI Name: Marina Orio

We plan to study unused archival observations of supersoft X-ray sources. The light curves will be examined, especially looking for non-radial oscillations of the WD, which have recently been discovered in novae and are an exciting new way to study the hot hydrogen burning WD of novae. Spectral analysis with new NLTE model atmospheres will be done with particular emphasis on exposures taken with the LETG grating, the only instrument that allows measurements of the effective gravity of the putative white dwarf and estimates of the chemical composition of its atmosphere. We will be able to compare very different sources, with each other and with classical novae in outburst.


Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 06500246

Title: Archival Study of Spin-powered Pulsars and Pulsar Wind Nebulae.

PI Name: George Pavlov

We propose to analyze the whole sample of spin-powered pulsars and pulsar-wind nebulae (PWNe) observed by Chandra. We will investigate the magnetospheric and thermal components of the pulsar radiation, systematize the PWN morphologies, study the spatially dependent PWN spectra, and establish most accurate correlations between the pulsar and PWNe parameters. We will create a database containg the X-ray properties of pulsars and PWNe and describe the results of our analysis of the PSR/PWN sample in a review paper.


Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 06500591

Title: Type Ia SNRs in the Large Magellanic Cloud: an Analysis of Archival Data

PI Name: Kazimierz Borkowski

Type Ia supernovae (SNe) are poorly understood although they play an important role in modern astrophysics. Remnants of Type Ia SNe provide us with a unique opportunity to learn about their explosion mechanisms and nucleosynthesis through spatially-resolved spectroscopy of X-ray emitting ejecta. We propose an archival study of Type Ia SNRs in the Magellanic Clouds. Our goal is to determine strengths of lines and their complexes, and their spatial distribution with nearly-model independent techniques, using the best available atomic data. We will also use standard multi-component fitting techniques in an attempt to deduce physical conditions and abundances in SN ejecta. The results will be compared with a grid of Type Ia models, leading to better understanding of Type Ia SNe and SNRs.


Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 06500783

Title: The Structural and Radiative Evolution of Cassiopeia A

PI Name: Lawrence Rudnick

Recent measurements of Cas A indicate a complex dynamical picture. Our work comparing two epochs of ACIS-S3 data show the rapid radiative evolution of the remnant. We propose here to use the third 50 ks observation of Cas A taken as a part of the 1 Ms VLP data set. With this new observation, we will be able to disentangle proper motions from brightness, structural and spectral changes. This will allow us to address two critical areas in the evolution of young SNRs: 1) the extent to which the structures arise from CSM interactions as opposed to the imprint of the SNe; and 2) an evaluation of the time scales regulating the radiative properties of the thermal and non-thermal plasmas.


Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 06500887

Title: Spatial Structure of Supernova Ejecta in Cassiopeia A

PI Name: Kazimierz Borkowski

Core-collapse supernovae probably explode as a result of strong turbulence and asymmetries. These inhomogeneities may be imprinted on the ejected material in ways still observable in young supernova remnants, hundreds of years later. We propose an archival study of the 1 Msec observation of Cas A, with the specific goal of applying statistical methods to quantify the turbulence and asymmetries. We plan a Fourier approach, which we will also apply to 3-D simulations, to allow quantitative comparisons between models and real data. There will be adequate signal to perform such analyses for different subregions, in different directions, and for different photon energies. This analysis technique is complementary to traditional spectral analysis.


Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 06500919

Title: A Quantitative Study of Clumping in Young Supernova Remnants

PI Name: Jessica Warren

We propose to use a new technique, Principal Component Analysis (PCA), to quantify clumping in four young, Galactic supernova remnants (SNRs) in the Chandra archive: Cas A, Tycho, G292.0+1.8, and Kepler. PCA is a robust, unbiased statistical technique, which we have already tested on an SNR (0509-67.5) that we have recently studied. Using PCA, we will compare spectral variations of regions within an SNR, taking advantage of Chandra's superb spatial resolution for spectroscopic studies on arcsecond scales. We are most interested in variations caused by clumping inhomogeneities, as these can yield important constraints on explosion mechanisms of supernovae.


Subject Category: NORMAL GALAXIES: DIFFUSE EMISSION

Proposal Number: 06610387

Title: Elliptical Galaxies in the Local Universe

PI Name: Christine Jones

X-ray emission from an early-type galaxies can arise from several mechanisms, including an AGN, galactic sources and hot gas. For nearby galaxies, Chandra's spatial resolution can distinguish the primary sources of X-ray emission. We propose to analyze archival ACIS observations for 96 early-type galaxies; total observation time is 3.25 million seconds! Our primary goals are to compare the X-ray luminosity of the SMBH to the black hole mass, measure the cycle time for nuclear outbursts, determine the impact of these outbursts on the gas in the galaxies, measure the extent and mass of the diffuse emission, and determine the galaxy mass when hot gas is no longer bound. We also will determine if the gas mass is correlated with galaxy magnitude or type or with the radio luminosity.


Subject Category: NORMAL GALAXIES: DIFFUSE EMISSION

Proposal Number: 06610666

Title: Dark Matter in Elliptical Galaxies

PI Name: Ewan O'Sullivan

While the brightest group and cluster dominant elliptical galaxies are believed to have large dark matter halos, some moderate luminosity ellipticals have been found to contain little or no dark matter. However, an X-ray mass estimate for one of these galaxies produces a conflicting result. We propose using archival Chandra data in the first systematic survey of mass profiles in ordinary ellipticals with X-ray halos, and comparing these to results from the Planetary Nebula Spectrograph kinematics program. This survey will provide a powerful new tool for studying the composition and structure of elliptical galaxies, and will for the first time allow us to make definitive statements about the dark halos of `average' elliptical galaxies.


Subject Category: NORMAL GALAXIES: X-RAY POPULATIONS

Proposal Number: 06620691

Title: An Archival Study of the Origin and Evolution of LMXBs in Elliptical Galaxies

PI Name: Steve Zepf

We propose to carry out an archival study of Chandra data on 15 elliptical galaxies to address several key questions about the nature and origin of LMXBs. Firstly, we will investigate whether the X-ray spectra of LMXBs in metal-rich globular clusters (GCs) are different than those in metal-poor GCs. Secondly, we will investigate whether the LMXBs not in GCs have a spatial distribution like the galaxy light, suggesting they are a true field population, or if the spatial distribution is more like that of the GC system, suggesting many of the field LMXBs originated in GCs and were ejected. This proposal builds on our previous archival program, which has produced a number of new results and multiple papers in the area of the LMXB populations and their connection to GCs.


Subject Category: NORMAL GALAXIES: X-RAY POPULATIONS

Proposal Number: 06620842

Title: X-ray Probes of Star-Formation Using Two Rich Archives: the Combined Power of Chandra and the SDSS

PI Name: Ann Hornschemeier

We propose an archival study of Chandra ACIS observations of normal and starburst galaxies contained within the Sloan Digital Sky Survey Data Release 2 area. Our goals are to "calibrate" the X-ray emission properties of galaxies at z=0.1,compare X-ray measures of star-formation with optical spectroscoic diagnostics, and construct a normal galaxy X-ray Luminosity Function. Currently there are 500 galaxies within 52 Chandra fields that have been sufficiently observed for this purpose; by the start of AO6 this will only increase. The SDSS database is useful for such a study as it has a wealth of optical spectroscopic properties measured. We propose for funding for salary, computers, page charges, and travel to a AAS meeting to present the results.


Subject Category: ACTIVE GALAXIES AND QUASARS

Proposal Number: 06700184

Title: The Spectral Energy Distributions of Low-Luminosity AGNs: An Opportunity to Probe New Accretion Physics

PI Name: Luis Ho

The spectral energy distributions (SEDs) of AGNs encode valuable information on the physics of accretion onto black holes. The SEDs of low-luminosity AGNs exhibit profound differences compared to those of classical Seyferts and quasars. The lack of the "big blue bump" suggests that low-luminosity AGNs accrete via a fundamentally different mode. We propose to significantly enlarge the current sample of SEDs for low-luminosity AGNs by combining new Chandra X-ray nuclear fluxes with existing high-resolution measurements in the radio (VLA) and in the UV, optical, and NIR (HST). This project will increase the current sample of SEDs by an order of magnitude and will provide strong constraints on a number of outstanding issues related to accretion physics in nearby galaxies.


Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 06800364

Title: Are Cluster Simulations Realistic? Observational Benchmarks for the Next Generation Cluster Simulations

PI Name: Megan Donahue

The time is ripe for pulling theoretical models together with the wealth of Chandra cluster observations. We have 2 resources: the Virtual Cluster Exploratorium (VCE) and a rich cluster archive. We propose to test cluster simulations by creating a suite of observational benchmarks from the Chandra archive, and using the same tools on the simulated data. We will produce observables and and moment-based descriptions of surface brightness, temperature, pressure, and entropy maps. We will make the first tests of predicted 2D spectral distributions of a representative sample of real and simulated clusters. We will test simulations not by how well they fit individual clusters but by how well they explain the range and correlation of observables (global, radial, spectral, and imaging.)


Subject Category: GALACTIC DIFFUSE EMISSION AND SURVEYS

Proposal Number: 06910866

Title: Galactic Corona or Local Group Intergalactic Medium?: An Archival Search

PI Name: Smita Mathur

The debate over the association of the OVI high velocity clouds (HVCs) with z~0 X-ray absorption lines towards extragalactic sightlines has important implications: do the OVI HVCs trace a Galactic corona or are they part of the Local Group intergalactic medium? We are using a multi-pronged approach to resolve this issue and this proposal is a part of it. This archival program is to study the environment of the Milky Way along multiple sightlines for OVII, OVIII, and NeIX absorption lines. Detection of these lines (or upper limits thereupon), together with OVI HVCs provides strong diagnostics on the physical conditions of the absorbing gas, with far-reaching implications for the baryon content in the Local Group, its dynamical stability, and theories of galaxy formation.


Subject Category: GALACTIC DIFFUSE EMISSION AND SURVEYS

Proposal Number: 06910867

Title: An Archival Analysis of Stellar Life-Cycles at the Galactic Center

PI Name: Michael Muno

We propose to analyze 580 ks of archival Chandra observations of the inner 300 pc of the Galaxy, in order to test models for the star formation history there, and to study the origin and fate of hot, X-ray emitting plasma that suffuses the region. Our analysis will: (1) measure the spatial distribution, luminosity function, and spectral properties of the X-ray point sources, (2) provide a catalog of sources with accurate astrometry in order to facilitate multi-wavelength studies, and (3) measure spatial variations in the temperature, density, and ionization state of the hot ISM.

Smithsonian Institute Smithsonian Institute

The Chandra X-Ray Center (CXC) is operated for NASA by the Smithsonian Astrophysical Observatory. 60 Garden Street, Cambridge, MA 02138 USA.   Email:   cxchelp@head.cfa.harvard.edu Smithsonian Institution, Copyright © 1998-2017. All rights reserved.