Accepted Cycle 12 Archive Proposals

Proposal Number	Subject Category	PI Name	Title
12200080	STARS AND WD	Beiersdorfer	Novel Coronal Temperature Determination using the Fe XVIII and Fe XIX lines observed with the HETGS
12400023	BH AND NS BINARIES	Yao	Calibrating Atomic Data with X-ray Absorption Lines
12500159	SN, SNR AND ISOLATED NS	Perna	Constraining the field topology of magnetars through spectral-timing analysis of the quiescent emission of XTEJ1810-197
12500721	SN, SNR AND ISOLATED NS	Lopez	Quantifying Chandra X-ray and Radio Morphologies of Supernova Remnants
12500806	SN, SNR AND ISOLATED NS	Posselt	Probing the faint end of the isolated neutron star population
12500878	SN, SNR AND ISOLATED NS	Desai	Probing Deeper Into the Spectrum: Line Identifications and Spectral Diagnostics in the Soft X-ray Regime
12610506	NORMAL GALAXIES: DIFFUSE EMISSION	Forman	The Effects of Environment and Supermassive Black Holes on Hot Gas in Early Type Galaxies
12620187	NORMAL GALAXIES: X-RAY POPULATIONS	Fabbiano	X-ray populations of different ages in spiral galaxies
12620775	NORMAL GALAXIES: X-RAY POPULATIONS	Kundu	A Multiwavelength Study of Low Mass X-Ray Binaries in the Bulge of M31
12700132	ACTIVE GALAXIES AND QUASARS	Ho	Completing the AGN Census for Nearby Galaxies (Archival Component)
12700755	ACTIVE GALAXIES AND QUASARS	Zezas	Chandra observations of a representative sample of LIRGs: extreme starbursts and AGNs in the nearby Universe
12700888	ACTIVE GALAXIES AND QUASARS	Civano	The Dark Matter -- AGN Connection and Weak Lensing
12800487	CLUSTERS OF GALAXIES	Hasler	Cosmology Independent Measurement of the Gas Mass Fraction Using Chandra and Sunyaev Zel'dovich Effect Observations
12800517	CLUSTERS OF GALAXIES	O'Sullivan	The History of AGN Feedback in Galaxy Groups: A Combined X-ray/Low-Frequency Radio Sample
12800838	CLUSTERS OF GALAXIES	HUMPHREY	The Dark Side of the Fundamental Plane
12900289	EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS	Green	The Interplay of Star formation and Accretion in the Local Universe
12900594	EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS	Galeazzi	Detection and Characterization of the WHIM with Chandra Archival Data
12910039	GALACTIC DIFFUSE EMISSION AND SURVEYS	Wang	Tomography of hot gas in and around the Milky Way

Subject Category: STARS AND WD

Proposal Number: 12200080

Title: Novel Coronal Temperature Determination using the Fe XVIII and Fe XIX lines observed with the HETGS

PI Name: Peter Beiersdorfer

We propose to determine the temperature of the coronal regions responsible for the Fe XVIII and Fe XIX emission using dielectronic recombination satellite lines. These lines are weak, but can be observed in the co-added HEG or MEG spectra of Capella. The results will be compared to the temperature derived from the differential emission measure, providing a much needed test of the underlying charge fraction calculations. Our analysis also addresses the recent discovery that the Fe XVIII and Fe XIX flux near 10 A does not match the flux near 100 A nor 1000 A observed with EUVE/FUSE, casting doubt on the HETGS calibration, atomic data, and inferred temperatures. Our work will open up a new way of determining the temperature, which can be applied in the future to the analysis of other coronae.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time

Subject Category: BH AND NS BINARIES

Proposal Number: 12400023

Title: Calibrating Atomic Data with X-ray Absorption Lines

PI Name: Yangsen Yao

X-ray absorption/emission lines of metal ions at various charge states have been observed in all kinds of astronomical objects. However, theoretical calculations for line centroids of K transitions of ions at low charge states are yet to merge. X-ray absorption lines produced in the Galactic ISM are expected to be at rest-frame wavelengths and thus are ideal references for calibrating these atomic data. We propose to combine 34 Chandra HETG observations of 11 Galactic low mass X-ray binaries to obtain a spectrum with unprecedented high signal-to-noise ratio, in which we can measure rest-frame wavelengths for the 1s-2p and 1s-3p transitions of OI-OIII, NeI-NeIII, and MgIII-MgIV (where applicable) as accurate as <=1 mA. This program is designed primarily for training undergraduate students.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 12500159

Title: Constraining the field topology of magnetars through spectral-timing analysis of the quiescent emission of XTEJ1810-197

PI Name: Rosalba Perna

While big strides have been made in understanding magnetar physics, a big puzzle remains on the crucial element responsible for the variety of observed phenomenology.If it is just the B field, then why neutron stars with the same inferred B would exhibit different behavior? To try to answer this question, we propose a spectral/timing analysis of the archival Chandra and XMM data of the magnetar XTE J1810-197 in quiescence. Previous work allowed us to constrain the viewing geometry.We now aim at constraining the temperature distribution of the quiescent emission. Since hotter regions track regions with more intense B field, we will be able to assess:a)the validity of the dipole assumption in measuring B fields;b)the role of the B topology in determining the observed magnetar phenomenology.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 12500721

Title: Quantifying Chandra X-ray and Radio Morphologies of Supernova Remnants

PI Name: Laura Lopez

Chandra has observed over one-hundred supernova remnants (SNRs) in the Milky Way and many more in external galaxies, yet no systematic analysis has been conducted to compare the multi-wavelength properties of these complex and diverse sources. Toward this end, we propose an archival study of thirty-one galactic and LMC SNRs. We will apply quantitative methods our group has developed to measure the symmetry, segregation, and sub-structure in extended sources. Our sample reflects SNRs of all types and a variety of ages, and detailed comparison of the X-ray and radio properties between them will provide crucial insights regarding the nature of explosions, the effects of heating and dense environments, and particle acceleration properties.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 12500806

Title: Probing the faint end of the isolated neutron star population

PI Name: Bettina Posselt

Isolated neutron stars are of supreme value but are extremely difficult to find, mainly due to the problem of source confusion in the usually large X-ray positional errors. This proposal aims to take advantage of the superb spatial resolution of Chandra to search for isolated neutron stars with thermal X-ray emission in the Chandra archive. Applying our latest population synthesis model we estimate that several such objects are lurking in the archive, with the highest likelihood for faint sources. Such objects will allow to probe the unexplored faint population of cooling isolated neutron stars. The initial candidates from the Chandra Source Catalogue are also faint enough to tap the expected elusive population of ISM-accreting neutron stars.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 12500878

Title: Probing Deeper Into the Spectrum: Line Identifications and Spectral Diagnostics in the Soft X-ray Regime

PI Name: Priya Desai

Accurate line identification is paramount for the analysis of any high-resolution spectrum. Recent LETG X-ray spectra of the Classical Nova KT Eri and Recurrent Symbiotic Novae RS Oph are super soft X-ray binary sources showing a strong continuum between 25 and 80 with numerous deep absorption lines. Stellar Atmosphere Codes (e.g. PHOENIX) rely heavily on the accuracy of line lists and atomic data such as oscillator strengths and electron collision rates. However, many of the lines in the soft X-ray band above 25 A are neither modeled nor even identified, presenting one of the major stumbling blocks in creating more detailed models of atmospheres and winds in various types of novae. We propose a three-pronged approach to improve the atomic data for analyzing soft X-ray spectra.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time

Subject Category: NORMAL GALAXIES: DIFFUSE EMISSION

Proposal Number: 12610506

Title: The Effects of Environment and Supermassive Black Holes on Hot Gas in Early Type Galaxies

PI Name: William Forman

We propose an archival study of a sample of at least 100 optically luminous early type galaxies fully accounting for their three emission components: hot gas, diffuse stellar component distributed as the K-band light, and LMXB's. We will search for, and analyze, surface brightness features (e.g., shocks, cavities, and ``cold fronts''), generate gas density and temperature profiles, compute pressure profiles for use with detected cavities to derive the mechanical power from the weak AGN in the sample galaxies, combine the observed AGN luminosities (in radio and X-ray) with the SMBH masses to investigate the accretion mode. Finally, we will prepare a public archive of the data products e.g., density, temperature, pressure, and entropy profiles, and images used in the investigation.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time

Subject Category: NORMAL GALAXIES: X-RAY POPULATIONS

Proposal Number: 12620187

Title: X-ray populations of different ages in spiral galaxies

PI Name: Giuseppina Fabbiano

Spiral galaxies offer a unique possibility to explore X-ray binary populations over a broad range of ages. We propose to use Chandra archival data of 10 nearby galaxies to study properties of X-ray populations as a function of age. Populations of similar ages will be selected based on their spatial location with respect to galactic structures. In order to increase statistics, equivalent regions of different galaxies will be combined. In total, we expect to detect ~800 X-ray binaries. This number is large enough to allow a meaningful investigation and comparison of XLFs, spectra and color-color diagrams. We will also investigate stellar kinematics in the disk using deviations of spiral structures seen in the distribution of X-ray sources from that observed in Ha, FIR and UV.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time

Subject Category: NORMAL GALAXIES: X-RAY POPULATIONS

Proposal Number: 12620775

Title: A Multiwavelength Study of Low Mass X-Ray Binaries in the Bulge of M31

PI Name: Arunav Kundu

We propose to study the field low mass X-ray binaries (LMXBs) in the bulge of M31 using archival Chandra ACIS data and search for the optical counterparts in archival HST optical images. Theoretical studies suggest that the large populations of bright LMXBs discovered by Chandra in the old stellar populations of elliptical galaxies and spiral bulges are likely to be dominated by Roche Lobe filling red giant branch (RGB) stars. The large, hot accretion disks in such systems should appear as bright as the tip of the RGB stars at visual wavelengths and be easily detectable. Our multiwavelength study will directly test whether the overwhelming majority of the field LMXBs are RGB systems. This study will also more than double the sample of Lx vs. Lopt for LMXBs with reliable distances.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time

Subject Category: ACTIVE GALAXIES AND QUASARS

Proposal Number: 12700132

Title: Completing the AGN Census for Nearby Galaxies (Archival Component)

PI Name: Luis Ho

The census of AGNs in the local Universe provides an efficient and effective estimate of the occupation fraction of central black holes in galaxies. While the demographics of AGNs in bulge-dominated systems is fairly well known, the situation in later-type galaxies is still murky because of potential optical selection biases. Searching for X-ray cores using Chandra can bypass these complications. We propose to complete the local AGN census by surveying all 188 star-forming (H II) nuclei in the well-studied Palomar sample of nearby galaxies. We request funding to analyze the 85 objects already in the archive; new observations have been proposed for the rest. We will establish with unprecedented reliability the AGN fraction across a wide range in Hubble type and Eddington ratios.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time

Subject Category: ACTIVE GALAXIES AND QUASARS

Proposal Number: 12700755

Title: Chandra observations of a representative sample of LIRGs: extreme starbursts and AGNs in the nearby Universe

PI Name: Andreas Zezas

We propose an archival Chandra study of a representative sample of 26 nearby (ultra)-luminous infrared galaxies. These objects are part of the HerCULES Herschel key project which aims in understanding the energetics and conditions in their molecular gas. The Chandra observations will provide key constraints on models of their far-infrared spectra obtained with Spitzer and Herschel. This way we will quantify the intensity of the AGN and starburst activity and measure the parameters (temperature, density) of the absorbing gas, and its distance from the ionizing source. These results will have important implications for studies of: (a) merger-induced activity, (b) high redshift star-forming galaxies and obscured AGNs, (c) X-ray emission from powerful starbursts.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time

Subject Category: ACTIVE GALAXIES AND QUASARS

Proposal Number: 12700888

Title: The Dark Matter -- AGN Connection and Weak Lensing

PI Name: Francesca Civano

The galaxy stellar mass function, and so presumably the SMBH mass, traces the growth of the Dark Matter halo (DMH) mass function. Observational studies are controversial and a clear picture regarding the connection between the X-ray luminosity and the DMH mass of AGN has yet to emerge. We propose to measure the DMH masses around the X-ray selected AGN at 0.3>z>1.2 with the galaxy-galaxy lensing technique. We will use a large number of Chandra COSMOS AGN, stacking them over a wide range of properties (redshift, X-ray luminosity, hardness ratio, obscuration, optical and X-ray AGN types), to explore the connection between galaxy formation, nuclear activity and DM environment as a function of these properties. This would be the first lensing study of AGN using Chandra.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800487

Title: Cosmology Independent Measurement of the Gas Mass Fraction Using Chandra and Sunyaev Zel'dovich Effect Observations

PI Name: Nicole Hasler

Joint analysis of X-ray and Sunyaev Zel'dovich Effect observations of galaxy clusters provides a direct measurement of the angular diameter distance of the cluster, which enables us to calculate the gas mass fraction without making any assumptions about the underlying cosmology. We propose to measure the gas mass fraction as a function of redshift for a sample 0f 30 relaxed clusters in the Chandra archive; this cosmology-independent gas mass fraction versus redshift measurement will provide rigorous support for cosmological constraints on $\Omega_{\Lambda}$ and $w$, using the methods described by Allen et al. (2008).

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800517

Title: The History of AGN Feedback in Galaxy Groups: A Combined X-ray/Low-Frequency Radio Sample

PI Name: Ewan O'Sullivan

AGN feedback is likely to be the most important mechanism for balancing radiative cooling in galaxy clusters and groups. Investigation of this process requires a combination of high quality X-ray and radio data, but at frequencies above 1 GHz many old radio structures are too faint to be detected. We have identified 21 groups which show signs of radio/X-ray interactions, and acquired deep multi-band GMRT low-frequency radio data which provides a dramatically improved ability to identify old AGN outbursts. Having already examined 9 systems, we request funding to support the analysis of archival Chandra data for the remaining 12. In combination with our radio survey and archival XMM data, we will examine the range of feedback modes, AGN power output and duty cycles in galaxy groups.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800838

Title: The Dark Side of the Fundamental Plane

PI Name: PHILIP HUMPHREY

In a recent, pilot survey of galaxies, groups and clusters, we found that the dark and luminous matter conspire to produce mass profiles that are remarkably close to a powerlaw. The slope of the mass profile, alpha, correlates tightly with the effective radius (Re) of the central galaxy, resulting in a strong relationship between Re and the dark matter fraction within it. Intriguingly, this relationship is exactly what is needed to produce the tilt of the fundamental plane (FP). If this effect accounts entirely for the FP, then the alpha-Re relation must be very tight. Since the present sample is too small to assess the scatter, we now propose to expand it with archival Chandra data and investigate these novel relations in more detail.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time

Subject Category: EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS

Proposal Number: 12900289

Title: The Interplay of Star formation and Accretion in the Local Universe

PI Name: Paul Green

Galaxy evolution and supermassive black hole growth are closely linked, but the inter-relationships between active accretion and star formation, AGN outflows, and host morphological trends remain poorly understood. We propose to study an unprecedented sample of 615 low redshift SDSS galaxies and AGN detected in archival Chandra fields. We will measure diverse optical and X-ray spectroscopic properties spanning the artificial galaxy/AGN divide, and provide detailed results of our model fitting. We highlight tests of (1) an evolutionary sequence from star-forming through AGN to passive galaxy modes (2) narrow line Sy1 galaxies and new parallels between the accretion modes of AGN and stellar mass X-ray binaries and (3) the relationship of host morphology and mergers to accretion.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time

Subject Category: EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS

Proposal Number: 12900594

Title: Detection and Characterization of the WHIM with Chandra Archival Data

PI Name: Massimiliano Galeazzi

Detecting and understanding the Warm-Hot Intergalactic Medium is made particularly difficult by the very week WHIM signal and the contamination from other sources. However, using a statistical approach we recently detected the WHIM signature in the angular correlation of XMM X-ray images. In this investigation we plan on taking using Chandra s superior angular resolution and long exposure in the Deep Field South (DFS) direction to investigate the properties of the WHIM, including the spatial distribution of the gas and its dependence on redshift. The existing extensive multiwavelength analysis on discrete sources already performed on the field makes it a unique, invaluable field for our investigation.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time

Subject Category: GALACTIC DIFFUSE EMISSION AND SURVEYS

Proposal Number: 12910039

Title: Tomography of hot gas in and around the Milky Way

PI Name: Q. Daniel Wang

Our Galaxy represents a unique laboratory in which we can conduct X-ray absorption line spectroscopy along multiple sight lines to explore the global distribution as well as the thermal, chemical, and kinetic properties of diffuse hot gas. We propose an archival research to systematically analyze the Chandra grating spectra of X-ray binaries and AGNs, toward which interstellar absorption by highly-ionized ions have been detected. We will jointly fit the spectra of a total 5 Ms exposure for 16 sight lines to model the global hot gas, using an analysis tool that allows for the inclusion of relevant X-ray emission and far-UV absorption line data. This modeling is badly needed for characterizing the global properties of the hot gas and determining its role in shaping the Galactic ecosystem.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time

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 © 1998-2024. All rights reserved.