Accepted Cycle 15 Archive Proposals

Proposal Number	Subject Category	PI Name	Title
15400717	BH AND NS BINARIES	Antoniou	The deepest census of extragalactic stellar and accreting populations ever
15300748	WD BINARIES AND CV	Bellm	Identifying Compact Binaries in the Chandra Source Catalog with Optical Variability
15200744	STARS AND WD	Drake	DOES INTRINSIC T TAURI X-RAY LUMINOSITY CONTROL PROTOPLANETARY DISK EVOLUTION AND PLANET FORMATION?
15900203	EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS	Green	AGN Selection and the Interplay of X-ray Properties and Variability
15700206	ACTIVE GALAXIES AND QUASARS	Greene	The Demographics of Massive Black Holes in Dwarf Galaxies
15620513	NORMAL GALAXIES: X-RAY POPULATIONS	Hornschemeier	HOT GAS AND BINARY PRODUCTION IN THE EARLIER UNIVERSE: X-RAY EMISSION FROM GALAXIES IN ISOLATED COMPACT GROUPS
15800792	CLUSTERS OF GALAXIES	Jeltema	Calibrating Optical Cluster Finding for Dark Energy Surveys with Archival Data
15900104	EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS	Kashlinsky	Looking for early black holes in Cosmic Backgrounds
15610427	NORMAL GALAXIES: DIFFUSE EMISSION	Kim	Resolving the puzzle of the X-ray luminosity scatter for early-type galaxies
15800518	CLUSTERS OF GALAXIES	Markevitch	CONSTRAINING THERMAL CONDUCTION WITH POWER SPECTRUM OF TEMPERATURE VARIATIONS IN CLUSTER MERGERS
15700568	ACTIVE GALAXIES AND QUASARS	Migliori	Tracing the X-ray jet emission in gamma-ray radio-loud quasars
15700695	ACTIVE GALAXIES AND QUASARS	Paggi	Compton-Thick AGNs in Chandra COSMOS ULIRGs
15500292	SN, SNR AND ISOLATED NS	Patnaude	An Archival Study of VER J2019+407 in the gamma-Cyg Supernova Remnant
15400277	BH AND NS BINARIES	Yaqoob	The Physical Properties and Structure of Matter Surrounding the Accretion Flow in X-ray Binaries
15700782	ACTIVE GALAXIES AND QUASARS	Yaqoob	Kinematics of the Circumnuclear Matter in AGN with HETG Spectroscopy of the Narrow Fe Ka Line
15620829	NORMAL GALAXIES: X-RAY POPULATIONS	Zepf	X-Raying the IMF in Elliptical Galaxies
15800597	CLUSTERS OF GALAXIES	Zhuravleva	Nature of gas density fluctuations in the Perseus Cluster: AGN feedback, turbulence and mergers

Subject Category: BH AND NS BINARIES

Proposal Number: 15400717

Title: The deepest census of extragalactic stellar and accreting populations ever

PI Name: Vallia Antoniou

We propose the analysis of archival Chandra ACIS observations of the area of the Supernova Remnant E0102-72.3 in the SMC, which yield a total of 1 Msec and 550 ksec for ACIS-I and ACIS-S. These data provide the deepest census of X-ray sources in a nearby galaxy extending by more than a factor of 10 previous studies in the Magellanic Clouds. The resulting depth of ~5x10^31 erg/s reaches well into the luminosities of normal stars, and it probes the regime of quiescent accreting binaries. With these observations we will study: (a) the X-ray emission of normal early-type stars in a low-metallicity environment, and its relation to metallicity; (b) the populations of quiescent accreting binaries, which will further constrain their formation efficiency; (c) their long-term variability.

Subject Category: WD BINARIES AND CV

Proposal Number: 15300748

Title: Identifying Compact Binaries in the Chandra Source Catalog with Optical Variability

PI Name: Eric Bellm

Compact binary systems are vital to understanding accretion physics and stellar evolution. They may be identified by their variable X-ray and optical signatures. We propose to use optical variability data from the Palomar Transient Factory and other synoptic surveys to find previously unidentified compact binaries in the Chandra Source Catalog. We will use additional spectroscopic resources to confirm these identifications and obtain physical parameters for the systems. In the process, we will distinguish compact binary candidates from other classes of X-ray emitting sources such as AGN and coronally-active stars. We will produce a catalog of optically variable Chandra Source Catalog sources with probabilistic classifications for many of the currently unidentified Chandra sources.

Subject Category: STARS AND WD

Proposal Number: 15200744

Title: DOES INTRINSIC T TAURI X-RAY LUMINOSITY CONTROL PROTOPLANETARY DISK EVOLUTION AND PLANET FORMATION?

PI Name: Jeremy Drake

Surveys of young clusters have found a surprisingly large X-ray luminosity spread among otherwise similar T Tauri stars - by more than two orders of magnitude. It cannot be explained by flares or variability on timescales of < 10 days, and points to large intrinsic Lx differences. T Tauri X-rays and associated energetic particles dominate the ionization of protoplanetary disks, driving MHD turbulent viscosity, accretion and photoevaporation. The types of planets formed in coagulation models depends on the viscosity, implying the X-ray luminosity of the star determines the outcome of planet formation. We propose a crucial test of this: whether Chandra observations of young clusters that have been observed at least twice, years apart, reveal larger Lx variations on longer timescales.

Subject Category: EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS

Proposal Number: 15900203

Title: AGN Selection and the Interplay of X-ray Properties and Variability

PI Name: Paul Green

Optical color selection has found the bulk of known QSOs, but largely those that are unabsorbed, luminous, point-like, and avoid the stellar color locus. X-ray emission and optical variability, both fundamental signatures of black hole accretion, will dominate AGN selection in the next decade via all-sky optical mappers like PanSTARRS (and later GAIA and LSST) and the upcoming eROSITA X-ray survey, providing QSO samples crucial for a variety of studies, including Large Scale Structure and Cosmology. We propose a large, pathfinding X-ray archival study across the PanSTARRS Medium Deep Fields and SDSS Stripe 82 to optimize AGN selection, and to study accretion across wide ranges of black hole mass, Eddington ratio, intrinsic absorption and radio power.

Subject Category: ACTIVE GALAXIES AND QUASARS

Proposal Number: 15700206

Title: The Demographics of Massive Black Holes in Dwarf Galaxies

PI Name: Jenny Greene

Using the 4 Ms Chandra deep field, we have found a few intriguing candidate massive black holes in the smallest host galaxies known to date. We propose a systematic search of deep fields in the Chandra archive to find more examples of these unique sources and to quantify the occupation fraction of nuclear activity in low-mass galaxies (with stellar masses < 10^9 M_sun). A robust measurement of the occupation fraction today can help discriminate between different formation channels for the first primordial seed black holes. Only deep, high-resolution Chandra imaging, combined with a wealth of multiwavelength data, is able to circumvent bias in host galaxy type and uncover the incidence of low-mass black holes in dwarf galaxies.

Subject Category: NORMAL GALAXIES: X-RAY POPULATIONS

Proposal Number: 15620513

Title: HOT GAS AND BINARY PRODUCTION IN THE EARLIER UNIVERSE: X-RAY EMISSION FROM GALAXIES IN ISOLATED COMPACT GROUPS

PI Name: Ann Hornschemeier

We propose to study the X-ray emission from 73 galaxies contained within 18 compact groups of galaxies. Compact groups are an environment in which important galaxy transformations occur and represent a local-universe analog to the types of galaxy interactions that were much more common at z>4. Our group has already analyzed the diffuse intragroup medium and X-ray point sources in a sample of 9 groups and has developed the techniques that will be required to excise the diffuse intragroup emission from the galaxy X-ray emission. We will investigate possible elevated point source X-ray luminosities in CG galaxies (as compared to field galaxies) as well as determine how the interactions in CGs affect the hot ISM of the galaxies.

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 15800792

Title: Calibrating Optical Cluster Finding for Dark Energy Surveys with Archival Data

PI Name: Tesla Jeltema

Clusters are a key component of large area optical imaging surveys designed to probe dark energy like DES and the LSST. However, the accuracy of the cosmological constraints derived from these surveys necessarily depends on having an optimized and well-calibrated algorithm for selecting clusters from photometric data as well as an optical richness whose mean relation and scatter compared to cluster mass are precisely known. We propose to use archival Chandra data for 145 clusters to calibrate and further optimize redMaPPer, the cluster finding algorithm which is being employed by DES.

Subject Category: EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS

Proposal Number: 15900104

Title: Looking for early black holes in Cosmic Backgrounds

PI Name: Alexander Kashlinsky

We propose analysis designed to improve previous measurements of cross-correlations in the unresolved CXB vs. CIB fluctuation in order to understand the early predecessors of Super Massive black holes. There is now observational evidence that the angular clustering of the fluctuations of the CIB exceed those from the remaining galaxy populations, yet it is unclear how much of these arise from stellar nucleosynthesis vs BH accretion. These CIB fluctuations were demonstrated to have a strong correlation with the unresolved CXB fluctuations. We will improve on the previous measurement by cross-correlating source-subtracted CIB maps from Spitzer/IRAC and Chandra unresolved CXB data in a much larger area of the Chandra COSMOS legacy field.

Subject Category: NORMAL GALAXIES: DIFFUSE EMISSION

Proposal Number: 15610427

Title: Resolving the puzzle of the X-ray luminosity scatter for early-type galaxies

PI Name: Dong-Woo Kim

It has long been recognized that there is a large amount of unexplained scatter in the relation between X-ray and optical luminosities for early-type galaxies. The solution to this puzzle may now be at hand, based on our novel, preliminary comparisons of Lx(gas) with halo masses M(total). The scatter appears to be enormously reduced, implying a surprisingly tight connection between hot gas and halo mass. If correct, this finding would provide an important new X-ray proxy for halo mass estimates, and also yield invaluable information about the co-evolution of galaxies and their hot ISM. We propose to verify and systematically explore the X-ray scaling relations, using archival Chandra data and high quality optical/NIR kinematics dataset, for 69 galaxies.

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 15800518

Title: CONSTRAINING THERMAL CONDUCTION WITH POWER SPECTRUM OF TEMPERATURE VARIATIONS IN CLUSTER MERGERS

PI Name: Maxim Markevitch

Accurate physical modeling of the intracluster medium is prerequisite to the use of clusters for precision cosmology. One of important but unknown ICM properties is its thermal conductivity. It affects cluster thermodynamics on scales from cool cores to the outskirts and can alter the cluster-wide distribution of gas density and temperature, directly affecting cosmological tests. Thermal conductivity is determined by the structure of the tangled magnetic fields in the ICM. We propose to obtain detailed temperature maps for several well-exposed hot mergers, derive the power spectra of temperature variations and determine their smallest scales. The results will serve as input for MHD simulations of mergers that include magnetic fields and different values for along-the-field conductivity.

Subject Category: ACTIVE GALAXIES AND QUASARS

Proposal Number: 15700568

Title: Tracing the X-ray jet emission in gamma-ray radio-loud quasars

PI Name: Giulia Migliori

We propose a study of the jet high energy emission of a sample of radio quasars using archival Chandra observations. The sample is formed by quasars with a detected gamma-ray blazar component and an extended X-ray jet. We aim at studying the evolution of the jet high energy emission from the small to the large scale. The results of the X-ray analysis together with multi-wavelength data will allow to infer the jet properties and test whether the power is efficiently carried in jets from vicinity of the central Black Hole to kiloparsec scales. The selected sample also has optical data and estimated BH masses. Accretion luminosities and rates can be derived and compared with jet power to shed a light on how accretion and ejection couple in powerful radio quasars.

Subject Category: ACTIVE GALAXIES AND QUASARS

Proposal Number: 15700695

Title: Compton-Thick AGNs in Chandra COSMOS ULIRGs

PI Name: Alessandro Paggi

We propose to constrain the incidence of CT AGNs in ULIRGs and investigate their cosmological evolution using the large unbiased sample of 22942 ULIRGs derived from the COSMOS and C-COSMOS surveys, performing both imaging and spectral stacking analysis of the C-COSMOS survey to: (1) measure the incidence of CT AGNs in ULIRGs galaxies of different luminosity and redshift by means of the prominent 'point-like' narrow 6.4 keV Fe-Ka emission; (2) perform a spectral study of the average emission of ULIRGs and their sub-samples to investigate the if these are characterized by the 6.4 keV Fe-Ka line typical of CT AGNs, or if the emission contains a sizeable contribution from the ionized Fe XXV 6.7 keV line which could be originating in the core of very strong starbursts.

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 15500292

Title: An Archival Study of VER J2019+407 in the gamma-Cyg Supernova Remnant

PI Name: Daniel Patnaude

The gamma-Cyg SNR is a shell-type remnant near the Cyg OB2 association. Recently, the VERITAS Cherenkov telescope detected TeV emission associated with a shock-cloud interaction in the northwest region of the SNR. The Fermi gamma-ray telescope has also detected emission from this region. We propose an archival study of Chandra observations of the gamma-Cyg SNR to investigate the nature of the coincident X-ray/GeV/TeV emission. We will compare these observations against models for nonthermal emission from shock-cloud interactions. We will combine these data with planned optical observations designed to resolve the radiative shocks which result when the SNR shock impacts the interstellar clouds. It is believed that these shocks may be responsible for accelerating particles to GeV energies.

Subject Category: BH AND NS BINARIES

Proposal Number: 15400277

Title: The Physical Properties and Structure of Matter Surrounding the Accretion Flow in X-ray Binaries

PI Name: Tahir Yaqoob

We propose to study the matter around the accretion flow in X-ray binaries using HETG, for 56 observations of 14 sources. We will use new models that self-consistently calculate the fluorescent X-ray line emission along with the absorbed and scattered continua. Previous work utilized ad hoc models, which cannot constrain the geometry, and they cannot correctly measure the fluorescent line widths or Fe abundance. They cannot take advantage of physical invariants between observations. We show that a uniform spherical geometery is inadequate. We will measure the Fe abundance for the first time, and constrain the dynamics better than previous modeling, which did not include the soft X-ray fluorescent lines. Thus, we will maximize the science return for this unprecedented data set.

Subject Category: ACTIVE GALAXIES AND QUASARS

Proposal Number: 15700782

Title: Kinematics of the Circumnuclear Matter in AGN with HETG Spectroscopy of the Narrow Fe Ka Line

PI Name: Tahir Yaqoob

We propose to extend our HETG spectroscopy studies of the Fe Ka line in AGN with 45 observations of 10 sources. The results from 33 of these observations of 9 AGN have not been published anywhere. We will measure the Fe Ka line centroid energy, luminosity, EW, and FWHM. In the context of the whole HETG sample, these results are building a vital picture of the properties of the X-ray reprocessing structure, and its relation to the optical BLR. The new results will also extend our previous work on the X-ray Baldwin effect, and the "calibration" of the relation between the Fe Ka line and [O III] and [O IV] line luminosities. Compared to previous analyses, we introduce and describe two innovative features to the methodology to give better kinematic constraints.

Subject Category: NORMAL GALAXIES: X-RAY POPULATIONS

Proposal Number: 15620829

Title: X-Raying the IMF in Elliptical Galaxies

PI Name: Steve Zepf

We propose to test recent claims that the stellar initial mass function (IMF) of massive early-type galaxies follows a steep power-law and is thus ``bottom heavy''. We will do this by comparing the number of neutron-star and black-hole X-ray binaries per stellar luminosity in high mass-to-light ratio early-type galaxies to the number in early-type galaxies with low mass-to-light ratios. If the high mass-to-light ratios are due to a steep, ``bottom-heavy'' IMF as claimed, then these galaxies should have fewer LMXBs per stellar luminosity. Such a test can be carried out with data available in the archive. This provides an invaluable and independent way to address the question of the IMF in early-type galaxies, which is a key question for may areas of astronomy.

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 15800597

Title: Nature of gas density fluctuations in the Perseus Cluster: AGN feedback, turbulence and mergers

PI Name: Irina Zhuravleva

We propose to measure the power spectrum of the ICM density/emissivity fluctuations in the Perseus Cluster using the archival Chandra data, the deepest (1.4 Ms) observations made of any cluster. Truly spectacular statistics accumulated by Chandra on Perseus (over 85 million counts within 6' from the center, with 100s and 1000s counts per sq.arcsec) makes this data set an extremely powerful tool to probe the ICM inhomogeneities down to per cent level on small scales. These data provide our best chance to measure density fluctuations over a broad range of spatial scales, placing constraints on a range of ICM microphysics (conduction and viscosity), and the physical mechanisms driving the inhomogeneities: AGN feedback, ongoing minor mergers and generic ICM turbulence.

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