Accepted Cycle 19 Archive Proposals

Proposal Number	Subject Category	PI Name	Title
19200002	STARS AND WD	Richard Ignace	Spectral Classification of Massive Stars Based on Their X-ray Spectra
19200037	STARS AND WD	Breanna Binder	Characterizing the X-ray Emission From Stellar Bow Shocks and Their Driving Stars with the Chandra Archive
19200055	STARS AND WD	Leisa Townsley	More MAGiX in the Chandra Archive
19200538	STARS AND WD	Rodolfo Montez	Shining the X-ray Light on Planetary Nebulae in Globular Clusters
19200559	STARS AND WD	Scott Engle	Living with a Red Dwarf: A Chandra Archival Study of dM Star Activity and Habitability
19400380	BH AND NS BINARIES	Kristen Garofali	Using HMXBs to Probe Massive Binary Evolution
19500502	SN, SNR AND ISOLATED NS	ROGER CHEVALIER	Understanding the Intriguing Nature of SN 2001em Through Archival Chandra Data
19500630	SN, SNR AND ISOLATED NS	Oleg Kargaltsev	Discovering extended sources in Chandra images
19620306	NORMAL GALAXIES: X-RAY POPULATIONS	Blagoy Rangelov	Multi-wavelength classification of X-ray sources in M33
19620594	NORMAL GALAXIES: X-RAY POPULATIONS	Francesca Fornasini	Does metallicity drive the redshift evolution of X-ray binary luminosity?
19700008	ACTIVE GALAXIES AND QUASARS	William Brandt	Understanding the X-ray Enhancements of Highly Radio-Loud Quasars in the Early Universe
19700082	ACTIVE GALAXIES AND QUASARS	Tesla Jeltema	The Effects of Environment on AGN Activity
19700120	ACTIVE GALAXIES AND QUASARS	Laura Brenneman	Investigating Supermassive Black Hole Spin in the Chandra COSMOS Legacy Survey
19700313	ACTIVE GALAXIES AND QUASARS	Ohad Shemmer	Identifying a Robust and Practical Quasar Accretion-Rate Indicator Using the Chandra Archive
19700369	ACTIVE GALAXIES AND QUASARS	Kendrah Murphy	The Dependence of AGN Properties on Inclination Angle
19700501	ACTIVE GALAXIES AND QUASARS	Guang Yang	Where Do Monsters Grow?
19700658	ACTIVE GALAXIES AND QUASARS	Jianfeng Wu	Quantifying the Role of CMB Photon Comptonization In the Lobes of Radio Galaxies
19700692	ACTIVE GALAXIES AND QUASARS	Renata Cumbee	MEASURING THE DETAILED PROCESSES OF CHARGE EXCHANGE IN M82: CHANDRA ANALYSIS OF MOLECULAR FILAMENTS
19800166	CLUSTERS OF GALAXIES	Andrea Morandi	Multi-phase gas, clumping and non-thermal pressure in cluster outskirts via X-ray, SZ and lensing data
19800684	CLUSTERS OF GALAXIES	Yuanyuan Su	A Systematic Study of Kelvin-Helmholtz Instability in Galaxy Clusters
19900027	EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS	Fabio Pacucci	Improving the Multi-Wavelength Capability of Chandra Large Programs
19900174	EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS	Akos Bogdan	Quantifying the average properties of hot gaseous coronae around spiral galaxies
19910212	GALACTIC DIFFUSE EMISSION AND SURVEYS	Esra Bulbul	The Galactic Halo Revealed in 94 Msec of Chandra Data
19910440	GALACTIC DIFFUSE EMISSION AND SURVEYS	John Tomsick	Constraining the Milky Way's Faint HMXB Population Using Archival Data

Subject Category: STARS AND WD

Proposal Number: 19200002

Title: Spectral Classification of Massive Stars Based on Their X-ray Spectra

PI Name: Richard Ignace

We propose to build up the classification of massive star X-ray spectra using the CXO archive. We have identified 9 stars with published spectra (but not included in the classification scheme) and 7 stars with unpublished spectra. Additionally, we anticipate adding 4-10 high S/N spectra from serendipitously observed sources. The major impact of the work will be to double the sample of Walborn et al., the majority of which will be B stars. Temperatures, emission measures, and diagnostic line ratios will be derived products of the effort. This work will greatly enhance our fundamental knowledge of massive stars, and form the framework for probing the weak-wind problem among B stars at X-ray wavelengths.

Subject Category: STARS AND WD

Proposal Number: 19200037

Title: Characterizing the X-ray Emission From Stellar Bow Shocks and Their Driving Stars with the Chandra Archive

PI Name: Breanna Binder

We propose an archival study of 2.8 Msec of ACIS images to search for X-ray emission from stellar-wind bow shocks and to characterize the X-ray properties of their driving stars. Bow shocks, particularly those produced by runaway OB stars, are theorized to up-scatter IR photons via inverse Compton scattering, and may produce a significant fraction of high-energy photons in our Galaxy. However, their low X-ray luminosity makes direct detection difficult. By stacking 106 archival observations containing >100 bow shocks, we will create the deepest X-ray exposure of bow shocks to date. We will perform the first detailed comparison of bow shock driving stars to the general massive star population.

Subject Category: STARS AND WD

Proposal Number: 19200055

Title: More MAGiX in the Chandra Archive

PI Name: Leisa Townsley

Massive star-forming regions (MSFRs) are engines of change across the Galaxy, providing its ionization, fueling the hot ISM, and seeding spiral arms with tens of thousands of new stars. Resolvable MSFRs are microscopes for understanding their more distant extragalactic counterparts, which provide the basis for star formation rate calibrations and form the building blocks of starburst galaxies. This archive program will extend Chandra's lexicon of MSFRs with in-depth analysis of 16 complexes, studying star formation and evolution on scales of tenths to tens of parsecs, distances <1 to >50 kpc, and ages <1 to 25 Myr. It fuses a "Physics of the Cosmos" mission with "Cosmic Origins" science, bringing new insight into star formation and feedback through Chandra's unique X-ray perspective.

Subject Category: STARS AND WD

Proposal Number: 19200538

Title: Shining the X-ray Light on Planetary Nebulae in Globular Clusters

PI Name: Rodolfo Montez

Planetary nebulae (PNe) are not expected to form in globular clusters (GCs), hence, the four known GC PNe present exciting challenges to our understanding of stellar evolution. Despite an abundance of optical and IR observations, the origin of these PNe is uncertain. There are two contending scenarios that could explain the origin of these GC PNe: (1) the transition time to produce a PNe could be faster than current models predict, or (2) the PN formation is assisted via binary interactions. Based on the Chandra Planetary Nebulae Survey, X-ray observations are particularly well-suited to provide the type of evidence required to rule on the origin of these PNe. Our proposal uses nearly two decades of archival Chandra observations and hundreds of ks to shine the X-ray light onto PNe in GCs.

Subject Category: STARS AND WD

Proposal Number: 19200559

Title: Living with a Red Dwarf: A Chandra Archival Study of dM Star Activity and Habitability

PI Name: Scott Engle

We propose to analyze 6 archival Chandra visits, not pointed at, but serendipitously including 3 dM stars of known age. GJ 669 AB are a common proper motion pair, each are resolved and detected in 3 exposures, and LHS 373 is a much older dM star also detected on 3 exposures. Photometry (by us) of GJ 669 AB began 5 years ago, is ongoing, and has precisely determined rotation rates for both stars and evidence of frequent flaring from GJ 669 B. We will analyze the multiple exposures, derive an accurate mean level of X-ray activity from the targets, and also separate out and individually analyze and model any observed X-ray flares. This proposal will provide highly accurate coronal properties for the targets, but also very useful data for stellar evolution and planetary habitability studies.

Subject Category: BH AND NS BINARIES

Proposal Number: 19400380

Title: Using HMXBs to Probe Massive Binary Evolution

PI Name: Kristen Garofali

We propose using deep archival Chandra data of M33 to characterize the distribution of physical parameters for the high-mass X-ray binary (HMXB) population from X-ray spectra, X-ray lightcurves, and identified optical counterparts coupled with ground-based spectroscopy. Our analysis will provide the largest clean sample of HMXBs in M33, including hardness, short- and long-term variability, luminosity, and ages. These measurements will be compared across M33 and to HMXB studies in other nearby galaxies to test correlations between HMXB population and host properties such as metallicity and star formation rate. Furthermore, our measurements will yield empirical constraints on prescriptions for models of the formation and evolution of massive stars in binaries.

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 19500502

Title: Understanding the Intriguing Nature of SN 2001em Through Archival Chandra Data

PI Name: ROGER CHEVALIER

Supernova (SN) 2001em was identified as a Type Ib/c stripped envelope supernova when it was discovered in 2001. By 2004, it showed an Halpha emission line characteristic of a Type IIn supernova, as well as bright emission at X-ray and radio wavelengths. The data support circumstellar interaction models (e.g., Chugai & Chevalier 2006). Of 5 Chandra observations starting in 2004, only the first has been published, in a telegram. We propose to reduce all 5 Chandra datasets on SN 2001em, as well as data from Swift, XMM-Newton, and radio observatories. These data will be used to develop a new model for the mass loss history of the progenitor star. The transition from Type Ib/c to IIn supernovae is very unusual and will give insight into late phases of massive star evolution.

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 19500630

Title: Discovering extended sources in Chandra images

PI Name: Oleg Kargaltsev

Chandra has taken thousands of images with unprecedented sub-arcsecond angular resolution and very low instrumental background in ACIS-I. These images represent the best hunting ground for cosmic objects with faint extended emission (e.g., SNRs, PWNe, galaxy clusters, planetary nebulae, etc.). Although, Chandra is well known for spectacular images of bright extended sources, no systematic effort to look for faint significantly extended sources have been made. Given the large number of images obtained such a search can only be performed automatically with a fast, efficient, and robust structure-finding algorithm. The goal of this proposal is to perform such a search in all archival ACIS images using the identified optimal algorithm and the HPC resources available at GW.

Subject Category: NORMAL GALAXIES: X-RAY POPULATIONS

Proposal Number: 19620306

Title: Multi-wavelength classification of X-ray sources in M33

PI Name: Blagoy Rangelov

We propose an archival study of the X-ray source population of M33. The final ChASeM33 source catalog (based on 1.4 Ms of Chandra data) contains 662 sources. Only a small fraction (1/4) of those have plausible identifications. The newly released Hubble Source Catalog (HSC) offers photometry for the large archival HST (often multi-band) data available for M33. We will use HSC jointly with X-ray data, to perform classifications with our existing automated machine-learning classification pipeline. We propose to modify our pipeline and apply it to all X-ray sources in the ChASeM33 source catalog. We expect to classify hundreds of previously unidentified X-ray sources in M33.

Subject Category: NORMAL GALAXIES: X-RAY POPULATIONS

Proposal Number: 19620594

Title: Does metallicity drive the redshift evolution of X-ray binary luminosity?

PI Name: Francesca Fornasini

Star forming galaxies at higher redshift (z) have increasingly higher X-ray luminosity (LX) for a given star formation rate (SFR). This trend has been attributed to the lower average metallicity (Z) of galaxies at higher z, which could result in a larger LX of HMXB populations. However, the first study directly testing this hypothesis suggests, but cannot rule out, that Z does not account for the higher LX/SFR of z~2 galaxies compared to z=0. We propose to investigate the LX/SFR vs. Z relation using a sample of z~0.3 galaxies with Z measurements from the SDSS survey and archival Chandra coverage. Combined with our current study at z~0.7, this will provide the most comprehensive measurements of the LX/SFR, Z, and z relation, only to be superseded by the next generation of X-ray telescopes.

Subject Category: ACTIVE GALAXIES AND QUASARS

Proposal Number: 19700008

Title: Understanding the X-ray Enhancements of Highly Radio-Loud Quasars in the Early Universe

PI Name: William Brandt

Highly radio-loud quasars (HRLQs) launch the most-powerful jets made by growing SMBHs in the Universe. We have recently found evidence that such HRLQs at z = 3-5.5 are about 3 times X-ray brighter than their matched counterparts at lower redshifts, perhaps due to a fractional IC/CMB contribution to the jet-linked core X-ray luminosity that grows rapidly with redshift. Here we propose Chandra and XMM-Newton archival analyses that should establish definitively these high-redshift X-ray enhancements and clarify their dependence upon redshift, allowing testing of the fractional IC/CMB model. The work will exploit both the significantly enlarged X-ray archives since our last studies as well as the greatly improved high-redshift quasar samples now available from SDSS-III BOSS.

Subject Category: ACTIVE GALAXIES AND QUASARS

Proposal Number: 19700082

Title: The Effects of Environment on AGN Activity

PI Name: Tesla Jeltema

We propose to use archival Chandra data for galaxies detected in the Dark Energy Survey to probe AGN activity as a function of environment and redshift. Our sample will include thousands of clusters and groups out to z~1 as well as thousands of field galaxies, allowing us to pinpoint the prime epochs and environments for AGN evolution. We will also provide important calibration of AGN contamination for cluster surveys with future telescopes.

Subject Category: ACTIVE GALAXIES AND QUASARS

Proposal Number: 19700120

Title: Investigating Supermassive Black Hole Spin in the Chandra COSMOS Legacy Survey

PI Name: Laura Brenneman

The past decade has seen a great advance in our ability to measure the spins of supermassive black holes (SMBHs) in AGN. In spite of our progress, however, the need to obtain very high signal-to-noise X-ray spectra to perform this science has left us with spin constraints in only 25 bright, local AGN. No approved observatory will greatly increase this number. In response, we propose an archival investigation of the AGN spectra from the Chandra COSMOS Legacy Survey to explore the evolution of SMBH spin with redshift. This large sample will allow us to perform a stacking analysis of thousands of spectra over 16 redshift bins out to z~5.3, probing correlations between spin and AGN luminosity, absorbing column, AGN type or other properties gleaned from the multi-wavelength COSMOS data.

Subject Category: ACTIVE GALAXIES AND QUASARS

Proposal Number: 19700313

Title: Identifying a Robust and Practical Quasar Accretion-Rate Indicator Using the Chandra Archive

PI Name: Ohad Shemmer

Understanding the rapid growth of supermassive black holes and the assembly of their host galaxies is severely limited by the lack of reliable estimates of black-hole mass and accretion rate in distant quasars. We propose to utilize the Chandra archive to identify the most reliable and practical Eddington-ratio indicator by investigating diagnostics of quasar accretion power in the hard-X-ray, C IV, and Hbeta spectral bands of a carefully-selected sample of optically-selected sources. We will perform a ``stress test'' to each of these diagnostics, relying critically on the hard-X-ray observable properties, and deliver a prescription for the most robust Eddington-ratio estimate that can be utilized economically at the highest accessible redshifts.

Subject Category: ACTIVE GALAXIES AND QUASARS

Proposal Number: 19700369

Title: The Dependence of AGN Properties on Inclination Angle

PI Name: Kendrah Murphy

According to the unified model, differences in the observed spectra of AGN depend largely on viewing angle. Understanding how the observed properties of AGN change with inclination angle is of utmost importance for constraining and refining unification schemes. Determining whether the AGN is aligned with the stellar disk of the host galaxy is also important for distinguishing between SMBH feeding mechanisms. Yet, in most cases the AGN inclination is unknown or poorly constrained. We propose to measure this parameter in 8 Seyfert galaxies with archival HETG, Suzaku, and NuSTAR data by self-consistently modeling the spectral signatures of the torus, thus independently testing results of a Hubble-STIS study, and investigating the dependence of X-ray spectral properties on polar angle.

Subject Category: ACTIVE GALAXIES AND QUASARS

Proposal Number: 19700501

Title: Where Do Monsters Grow?

PI Name: Guang Yang

Observations of nearby SMBHs show that black-hole mass is tightly related to host-galaxy properties, indicating a scenario of SMBH-galaxy coevolution. We have recently found that, for galaxies with low and intermediate stellar mass (M*), long-term black hole accretion rate (BHAR) is primarily linked to M* rather than star formation rate (SFR), and that BHAR is linearly correlated with M*. However, due to limited sample size in the study, the BHAR-M* and BHAR-SFR relations are not clear in massive systems, where AGN feedback could be important. Also, possible redshift evolution is not well constrained. To address these issues, we propose to extend our study to a much larger sample by analyzing Chandra and XMM-Newton archival observations.

Subject Category: ACTIVE GALAXIES AND QUASARS

Proposal Number: 19700658

Title: Quantifying the Role of CMB Photon Comptonization In the Lobes of Radio Galaxies

PI Name: Jianfeng Wu

We propose to assess the scientific viability of CMB quenching of high-z radio galaxies by studying a sample of 50 lobe-dominated (FR II) radio galaxies with existing, deep Chandra coverage, to be combined with an array of lower frequency data, available for all targets. Specifically, we will be applying the SED model developed by Ghisellini et al. (which includes emission from the core, jet, lobes and hotspots) to determine, for each system (1.) whether/under which physical conditions the lobe radio synchrotron emission is efficiently suppressed in favor of X-ray emission; (2.) whether CMB vs. far IR photons dominate the seed photon field for IC, and (3.) whether there is evidence for any systematic, redshift-dependent effect.

Subject Category: ACTIVE GALAXIES AND QUASARS

Proposal Number: 19700692

Title: MEASURING THE DETAILED PROCESSES OF CHARGE EXCHANGE IN M82: CHANDRA ANALYSIS OF MOLECULAR FILAMENTS

PI Name: Renata Cumbee

Charge exchange (CX), a collisional process between highly charged ions and neutral gas, has been established as a significant source of X-rays in the starburst galaxy M82. Although the CX is thought to occur at the interface of the cold filaments with the hot outflow, this spatial association has not yet been demonstrated. We propose to analyze the ~ 1 Ms of archival ACIS observations of M82 to search for a spatial correlation between CX spectral features and known molecular filament regions, making use of up-to-date and accurate CX models developed by our group. This analysis will help us understand the dynamics and physical processes in starburst galaxies which contribute to the metal enrichment in the ISM.

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 19800166

Title: Multi-phase gas, clumping and non-thermal pressure in cluster outskirts via X-ray, SZ and lensing data

PI Name: Andrea Morandi

We propose to study multitemperature structure, clumpy gas distribution and non-thermal pressure in the outskirts of a sample of galaxy clusters by means of Chandra X-ray, Sunyaev Zeldovich and lensing data. We propose to recover the X-ray spectroscopic temperatures close to the virial radius and compare them to the average (gas mass-weighted) temperature probed through SZ. Our preliminary analysis reveals compelling evidence of a substantial amounts of cold gas (T~0.8 keV) at subvirial temperature which coexists with the hot (>4 keV) thermal component of the intracluster medium (ICM). The proposed investigation has important implications for understanding the astrophysics of the ICM in the outer volumes and the CDM scenario, and it has crucial ramifications for the cosmology.

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 19800684

Title: A Systematic Study of Kelvin-Helmholtz Instability in Galaxy Clusters

PI Name: Yuanyuan Su

Kelvin-Helmholtz instabilities (KHI) were observed at cold fronts in a handful of clusters. KHI are predicted at all cold fronts in hydro simulation of intracluster medium (ICM). Their presence and absence provides a unique probe of transport processes in the hot plasma, which are essential to the dissipation and redistribution of the energy in the ICM. We propose the first systematic study of the prevalence of KHI in galaxy clusters by analyzing the archived Chandra observations of a sample of ~50 nearby galaxy clusters. We will associate the occurrence and properties of KHI rolls with various cluster parameters such as their gas temperature and density, and put constraints on effective transport coefficients in the ICM

Subject Category: EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS

Proposal Number: 19900027

Title: Improving the Multi-Wavelength Capability of Chandra Large Programs

PI Name: Fabio Pacucci

In order to fully exploit the joint Chandra/JWST/HST ventures to detect faint sources, we urgently need an advanced matching algorithm between optical/NIR and X-ray catalogs/images. This will be of paramount importance in bridging the gap between upcoming optical/NIR facilities (JWST) and later X-ray ones (Athena, Lynx). We propose to develop an advanced and automated tool to improve the identification of Chandra X-ray counterparts detected in deep optical/NIR fields based on T-PHOT, a software widely used in the community. The developed code will include more than 20 years in advancements of X-ray data analysis and will be released to the public. Finally, we will release an updated catalog of X-ray sources in the CANDELS regions: a leap forward in our endeavor of charting the Universe.

Subject Category: EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS

Proposal Number: 19900174

Title: Quantifying the average properties of hot gaseous coronae around spiral galaxies

PI Name: Akos Bogdan

Hot gaseous coronae within the dark matter halos of massive spiral galaxies is a fundamental prediction of galaxy formation models. Although the first X-ray coronae around massive spirals have been detected recently, their average characteristics remain poorly understood due to their faint nature. This program aims to overturn this picture and measure the average properties of the hot coronae beyond the stellar body of spiral galaxies. We propose to stack the X-ray data of a large number of massive spirals observed within wide-area Chandra survey fields. The observed properties of the coronae will be confronted with state-of-the-art galaxy formation models, which will allow us to constrain crucial physical processes that influence galaxy evolution.

Subject Category: GALACTIC DIFFUSE EMISSION AND SURVEYS

Proposal Number: 19910212

Title: The Galactic Halo Revealed in 94 Msec of Chandra Data

PI Name: Esra Bulbul

A well-motivated warm dark matter candidate, sterile neutrinos, can radiatively decay and emit X-rays detectable in observations of large dark matter aggregations such as galaxies and clusters of galaxies. An unidentified emission line has been observed at an energy of 3.5 keV in a variety of dark matter dominated objects. Despite intensive efforts, the origin of this unidentified line remains uncertain. We propose to stack 94 Msec of Chandra archival observations towards the Galactic Halo to investigate the origin of this signal by correlating the flux with the angular distance from the Galactic Center. This program will also allow us to map the temperature and surface brightness of the Halo gas with latitude and help identify its origin.

Subject Category: GALACTIC DIFFUSE EMISSION AND SURVEYS

Proposal Number: 19910440

Title: Constraining the Milky Way's Faint HMXB Population Using Archival Data

PI Name: John Tomsick

In the first 40 months of sensitive hard X-ray observations with the Nuclear Spectroscopic Telescope Array, nearly 500 sources have been detected serendipitously. While the effort to determine the nature of these sources has been very successful at high Galactic latitudes, identifications close to the Galactic plane have been more difficult because of source crowding and optical extinction. Only six 8-24 keV sources within 5 deg of the plane have been classified, and two of them are High-Mass X-ray Binaries (HMXBs), leaving open the possibility of a large population of faint HMXBs. We propose an archival study of 13 unclassified sources, including obtaining subarcsecond positions, which, along with joint near-IR imaging, will be used to find counterparts and determine their nature.