Accepted Cycle 16 Archive Proposals

Proposal Number	Subject Category	PI Name	Title
16200448	STARS AND WD	Konstantin Getman	Star Formation in Nearby Clusters (SFiNCs)
16400419	BH AND NS BINARIES	Jon Miller	Chandra's Third Degree for X-ray Binaries
16400627	BH AND NS BINARIES	Victoria Grinberg	The evolution of disk winds with x-ray spectral states in neutron star low mass x-ray binaries
16400738	BH AND NS BINARIES	Robert Hynes	Longer & Sharper, Deeper & Wider: Leveraging the Chandra Archive to Maximize the Yield of the Galactic Bulge Survey
16500222	SN, SNR AND ISOLATED NS	Rosalba Perna	Spectral-timing analysis of the low-B magnetar SWIFT J1822.3-1606: testing our understanding of the magnetar behavior
16500851	SN, SNR AND ISOLATED NS	Adam Foster	SN87A's Progenitor \& Ejecta Abundances from a New NEI Model
16610450	NORMAL GALAXIES: DIFFUSE EMISSION	Dong-Woo Kim	Chandra Early-Type Galaxy Atlas
16610785	NORMAL GALAXIES: DIFFUSE EMISSION	Rebecca Canning	ESTABLISHING THE ORIGIN OF HOT GAS IN EARLY TYPE GALAXIES
16620799	NORMAL GALAXIES: X-RAY POPULATIONS	Giacomo Vianello	Detecting short X-ray transients in the Chandra archive
16700216	ACTIVE GALAXIES AND QUASARS	Julia Comerford	Discovering Offset AGN in the Chandra Archives to Constrain the Connection between AGN and Galaxy Mergers
16700615	ACTIVE GALAXIES AND QUASARS	Eileen Meyer	The X-ray Variability of Large-scale Jets: A Chandra Legacy Project
16800247	CLUSTERS OF GALAXIES	Randall Smith	Confronting Chandra Spectroscopy with Experimental Measurements: Testing the Unidentified 3.55 keV Line
16800872	CLUSTERS OF GALAXIES	Simona Giacintucci	Why some cluster cool cores become particle accelerators?

Subject Category: STARS AND WD

Proposal Number: 16200448

Title: Star Formation in Nearby Clusters (SFiNCs)

PI Name: Konstantin Getman

We propose an archive study of 19 star forming regions within 1 kpc to provide detailed study of the pre-main sequence populations for comparison with our earlier MYStIX survey of richer, more distant clusters. Using state-of-the-art X-ray analysis of Chandra fields, combining with infrared stars, we will perform morphological analysis to identify (sub)clusters and age analysis to estimate their ages. The results will be compared to richer clusters and astrophysical star cluster formation calculations to elucidate star formation histories and dynamical evolution in smaller molecular clouds.

Subject Category: BH AND NS BINARIES

Proposal Number: 16400419

Title: Chandra's Third Degree for X-ray Binaries

PI Name: Jon Miller

The best HETGS observations of X-ray binaries have yielded some important results, including the detection of strong disk winds, insights into disk physics, and an anti-correlation between X-ray winds and relativistic radio jets. But, the best resolution of the HETGS has not been exploited. Even when the HETG is used with the ACIS-S array in ``CC'' mode, the 3rd-order can be recovered, and it delivers 3X better resolution than standard 1st-order spectra. Especially as we look ahead to the Astro-H era, we propose an archival study of 3rd-order HETG spectra of bright binaries. We will utilize the best possible photoionizaton grids, and push new versions of these models so their limits. Early results from these spectra are extremely promising.

Subject Category: BH AND NS BINARIES

Proposal Number: 16400627

Title: The evolution of disk winds with x-ray spectral states in neutron star low mass x-ray binaries

PI Name: Victoria Grinberg

Observations of black hole and neutron star low mass X-ray binaries (LMXBs) have revealed blue-shifted highly ionized absorbers that are indicative of outflows. Ponti et al. (2012) have recently shown that disk winds are ubiquitous in BH-LMXBs in the jet-free soft states. As the mass carried away in these winds can reach the inner accretion rate, this fuels speculation that they may suppress the jets. Is the jet-disk connection defined by the accretion flow only or does it depend on the compact object? NS-jets have been claimed to have a smaller power than BH-jets - how does this influence the winds? What are the implications for the wind launching mechanism? To address this we propose a systematic investigation of the connection of disk winds with the spectral states of NS-LMXBs.

Subject Category: BH AND NS BINARIES

Proposal Number: 16400738

Title: Longer & Sharper, Deeper & Wider: Leveraging the Chandra Archive to Maximize the Yield of the Galactic Bulge Survey

PI Name: Robert Hynes

The Galactic Bulge Survey (GBS) has found 1640 X-ray sources in a region of the Bulge for which extensive multiwavelength follow-up is both feasible, and underway. The primary goals are to detect new quiescent low-mass X-ray binaries with which to test binary evolution models, and measure black hole and neutron star masses. The GBS observations represent a fraction of the Chandra data available in this area, and a full analysis of the remainder can substantially enhance the GBS yield. Our study will focus on four possibilities inherent in the archival data: i) Longer observations with which to classify GBS sources; ii) Sharper localizations with which to identify optical counterparts; iii) Deeper and wider observations yielding new X-ray sources for which we already have optical data.

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500222

Title: Spectral-timing analysis of the low-B magnetar SWIFT J1822.3-1606: testing our understanding of the magnetar behavior

PI Name: Rosalba Perna

AXPs and SGRs are young neutron stars (NSs) characterized by high X-ray quiescent luminosities, outbursts, and sporadic giant flares (the SGRs). They are believed to be powered by ultra-strong B fields. However, the observation of outbursts from 'low-B' NSs has been a long-standing puzzle. Theoretical work by our group has shown that a) outbursts from a 'low-B' NS can be produced if the NS has a very strong internal toroidal field; b) a strong internal toroidal field can be revealed by spectral and timing analysis of the NS pulse profile. Here we propose to perform a detailed modeling of the spectra and pulse profile of the low-B magnetar SWIFT J1822.3-1606 with the aim of inferring its magnetic field topology and viewing geometry.

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500851

Title: SN87A's Progenitor \& Ejecta Abundances from a New NEI Model

PI Name: Adam Foster

Since 2007, SN 1987A has been observed with the gratings on Chandra at least once per year. This large catalog of high resolution spectra present a rich opportunity for the study of the evolution of non-equilibrium (NEI) plasmas. Several studies of the SNR's evolution have been already published in parts, with some looking at the high resolution spectra in detail. We have recently completed major updates to the AtomDB database, designed to improve modeling of NEI plasmas, in particular young shocks. Comparison with the previous NEI models show not-insignificant differences. In light of this we wish to re-analyze the existing archival data: this will provide both a test of our models and a chance to reassess such values as the Si abundance.

Subject Category: NORMAL GALAXIES: DIFFUSE EMISSION

Proposal Number: 16610450

Title: Chandra Early-Type Galaxy Atlas

PI Name: Dong-Woo Kim

We propose to systematically analyze the archival Chandra data of 137 early type galaxies to derive uniform data products of spatially resolved dataset with additional spectral information. We will make these products publicly available and also use them to study gas morphlogy, scaling relations, mass profile, circum-nuclear gas and LMXBs.

Subject Category: NORMAL GALAXIES: DIFFUSE EMISSION

Proposal Number: 16610785

Title: ESTABLISHING THE ORIGIN OF HOT GAS IN EARLY TYPE GALAXIES

PI Name: Rebecca Canning

A recent paradigm shift in theories of early-type galaxy evolution has put the hot gas content of such systems front and centre. Both Kormendy et al. and the ATLAS3D team have suggested a revision of the Hubble tuning fork to a parallel sequence with the existence of two kinds of ETGs; disky/fast-rotating and core/slow-rotating. These classes should be distinguishable by their hot gas content with SR having large X-ray halos while FR are dominated by discrete sources. We request support for an indepth study of >150 ETGs (9,648 ks); 10 times larger and significantly less biased than previous studies, providing a highly complete sample of AGN, LMXBs and gas in ETGs. Chandra has enormous potential for studies of galaxy evolution; the catalogued ETGs will provide an important legacy dataset.

Subject Category: NORMAL GALAXIES: X-RAY POPULATIONS

Proposal Number: 16620799

Title: Detecting short X-ray transients in the Chandra archive

PI Name: Giacomo Vianello

There are many known sources emitting short X-ray outbursts, ranging from minutes to less than a second (SGRs,GRBs,LMXB,late-type stars...). However, even the most comprehensive study of Chandra data, the Chandra Source Catalog, still leaves essentially unexplored short transients of duration < 1 ks. Indeed, their analysis has a very limited sensitivity for such sources, especially off-axis where the background contamination is more important. We will implement a blind-search algorithm for short transients in a large sample of Chandra data, featuring an order-of-magnitude improvement in sensitivity with respect to the CSC. This will open the possibility to detect many transients and associate them with existing catalogs of sources, as well as open a new unexplored space for discoveries.

Subject Category: ACTIVE GALAXIES AND QUASARS

Proposal Number: 16700216

Title: Discovering Offset AGN in the Chandra Archives to Constrain the Connection between AGN and Galaxy Mergers

PI Name: Julia Comerford

We propose a Chandra archival project to identify X-ray bright AGN that are spatially offset from their host galaxy cores. These offset AGN are unambiguous signs of galaxy mergers. Through the extensive data available in the Chandra archives, we will assemble the first catalog of confirmed offset AGN. In a pilot study we have already identified 2 offset AGN in the Chandra archives, demonstrating the effectiveness of our technique and suggesting that we will uncover ~40 offset AGN in total. The final sample will allow us to 1) constrain the role that galaxy mergers play in supermassive black hole (SMBH) accretion; 2) identify the different triggering mechanisms in single versus dual activation of SMBHs in galaxy mergers; and 3) calibrate future offset AGN selection techniques.

Subject Category: ACTIVE GALAXIES AND QUASARS

Proposal Number: 16700615

Title: The X-ray Variability of Large-scale Jets: A Chandra Legacy Project

PI Name: Eileen Meyer

The X-rays of powerful kpc-scale quasar jets are believed to be inverse Compton scattering of CMB photons (IC/CMB). However we recently ruled out this model in favor of a synchrotron nature for 3C 273 and PKS 1136-135 using Fermi and HST polarimetry, respectively. Because the two models imply radically different jets it is important to generalize our result. X-ray variability, which rules out IC/CMB, but is plausible for synchrotron has been detected in the jets of M87, Pictor A and in preliminary work on two quasar jets we present. We propose to analyze archival observations of over 40 jets, both weak and powerful, for variability over Chandraʼs lifespan, to confirm the synchrotron case for powerful sources and constrain the size, magnetic field, and physics of the emitting region.

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 16800247

Title: Confronting Chandra Spectroscopy with Experimental Measurements: Testing the Unidentified 3.55 keV Line

PI Name: Randall Smith

Two analyses of Chandra and XMM-Newton cluster observations found evidence for an as-yet unidentified emission line at ~3.55 keV. The line could be a sterile neutrino, with major implications for galaxy formation and cosmology. However, a number of more pedestrian explanations exist for the emission line, one of which is the possibility that it results from an unexpectedly strong dielectronic recombination satellite line created when He-like Ar+16 recombines to form Li-like Ar+15. Atomic theory suggests this scenario is unlikely, but experimental laboratory tests would be conclusive. We propose to use an Electron Beam Ion Trap to make measurements of the spectrum of Ar XVII and Ar XVI at a range of electron energies and compare the measurements to archival Chandra observations.

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 16800872

Title: Why some cluster cool cores become particle accelerators?

PI Name: Simona Giacintucci

We propose to study the Chandra archival data on clusters that exhibit a rare phenomenon of radio minihalos in their cores. We have recently discovered a relation of the minihalos with cold fronts in the cluster cool cores. Our subsequent hydrodynamic simulations suggested that sloshing in cool cores may produce turbulence capable of re-accelerating the pre-existing, aged relativistic electrons from past AGN activity and explain many observed features of the minihalos. It is a mystery, however, why some cool cores have minihalos and some don't. We will address this with our in-depth X-ray study of (a) a mass-limited cluster sample using Planck and (b) a full sample of known minihalos, which includes our recently discovered new minihalos.

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