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Proposal Number: 10700007

Title: The Disk-Jet Connection in Seyfert-1 AGN

PI Name: Jon Miller

A "fundamental plane'' of black hole activity has recently been found, possibly indicating that a specific disk-jet coupling governs all black holes. The potential importance of this relation demands that it be tested rigorously. Correlations between X-ray and radio flux are observed in individual stellar-mass black holes that bolster the robustness of the implied coupling. Similar correlations should hold in all black hole classes on the plane. We propose to make a careful search for correlated variability in the Seyfert-1 galaxy NGC 4051 via 10 short (10 ksec each) and contemporaneous Chandra and VLA observations. NGC4051 displays strong X-ray variability on the timescale of weeks and months, and has a moderately-bright radio core (0.5 mJy at GHz frequencies).

Proposal Number: 10700034

Title: X-ray spectroscopy of a recoiling SMBH candidate

PI Name: Peter Predehl

Recent numerical relativity simulations of coalescencing supermassive black hole (SMBH) binaries predict that SMBHs can receive kicks with velocities up to several thousand km/s due to anisotropic emission of gravitational waves. We have recently found the best candidate todate for such a recoiling SMBH (Komossa et al. 2008). We apply for a 25 ks ACIS-S exposure of this exceptional source.

Proposal Number: 10700038

Title: Longterm Monitoring of the Centaurus A Jet, ULXs, and Low Mass X-ray Binary Population

PI Name: Stephen Murray

We propose a 50 ks Chandra/ACIS-S and 4x5 ks ACIS-I observations of the nearby early-type galaxy Centaurus A to monitor the X-ray jet and X-ray binary population. We will search for proper motions of the X-ray knots, and continue our ongoing monitoring the X-ray fluxes and spectra for all the knots in the jet. The energy loss timescale of the synchrotron emission from the jet is of the order of years in the equipartition magnetic fields. In addition, we will observe the two known ULXs to determine their spectral states if active, and study the rest of the X-ray binary population down to an X-ray luminosity of 1E37 ergs/s in the 0.1-10.0 keV band. We will continue our monitoring campaign of the LMXB population to a sensitivity unmatched in any other early-type galaxy.

Proposal Number: 10700045

Title: Obtaining High Signal on the Fe-L Unresolved Transition Array

PI Name: Claude Canizares

We request 250 ksec of Chandra HETGS observations of the Seyfert 1 Ark 564. This source is known to have a broad range of ionized absorbers in outflow, seen against the strong soft continuum. The primary goal of these observations is to study the unresolved transition array (UTA) of Fe-L in this source, which provides the highest continuum level at the UTA of any previously studied active galaxy. We will also examine the response of the ionized warm absorber components to rapid variability, which is common in this source, a narrow line Sy1 galaxy. Finally, we will be able to place better limits on any narrow components of the neutral or ionized Fe emission lines.

Proposal Number: 10700069

Title: Flaring galaxies with strong emission-line light echo

PI Name: Peter Predehl

We propose two ACIS-S observations of the fading X-ray flare of the galaxy J0952+21 and one ACIS-S observation of the galaxy J1241+44. J0952+21 is unique in showing a very intense optical and NIR emission-line light echo in response to a high-energy flare which we also detected in the optical, NUV and NIR continuum (Komossa et al. 2008). The flare was likely caused by a stellar tidal disruption event. J1241+44 shows a similarly unusual optical emission-line spectrum, and we suspect a similar mechanism at work as in J0952+21.

Proposal Number: 10700080

Title: Studying the Optical and X-ray Emission Regions of Quasar PG 1115+080 by Monitoring Microlensing Events

PI Name: Gordon Garmire

We propose to apply the microlensing method to constrain the spatial structure of the optical and X-ray continuum emission regions of the quasar PG 1115+080 by comparing the flux ratios of the images in the X-ray and optical over several epochs. The differential changes in the flux ratios with wavelength will then constraint the relative sizes of the optical and X-ray emission regions.

Proposal Number: 10700081

Title: A Chandra Snapshot Survey of Bright Mini-BAL Quasars

PI Name: Gordon Garmire

We propose to obtain short Chandra snapshots of a a well-defined sample of the optically-brightest radio-quiet quasars (QSOs) in the SDSS Data Release 5 QSO catalog which host CIV broad absorption lines (BALs) with velocity widths between 1000 and 2000 km/s. We will compare the X-ray properties of this ``mini-BAL'' QSO sample to those of unabsorbed QSOs and also to traditional BAL QSOs, which have velocity widths >2000 km/s and are typically strongly X-ray absorbed. This will enable us to extend studies of BAL QSO X-ray properties to a new regime, and will also test whether mini-BAL QSOs are physically similar to BAL QSOs or are a separate population of objects.

Proposal Number: 10700119

Title: Tracking the Aftermath of the Giant Flare in the M87 Jet

PI Name: Daniel Harris

We request a continuation of our monitoring of the M87 jet. The primary driver is the large X-ray/Optical outburst of the jet knot, HST-1. Both the optical and X-ray intensities peaked at a level 50 times larger than that found in year 2000. We have also now detected superluminal motions of radio components of HST-1 with the VLBA. Many of the characteristics of these events are similar to blazar variability but HST-1 is clearly resolved from the nuclear emission of M87 at a projected distance of 60pc. We are coordinating our program with ground based gamma ray experiments which are monitoring M87, and GLAST should be operational during the AO10 Chandra year, thereby providing the possibility of confirming the predicted inverse Compton emission from the compact component(s) of HST-1.

Proposal Number: 10700121

Title: Testing the Radio-loud vs Radio-quiet AGN Dichotomy through the Ionized Circumnuclear Gas in 3C 445

PI Name: Rita Sambruna

The circumnuclear environment of Seyferts contains photoionized gas responsible for complex X-ray absorption/emission. Evidence for such a component in radio-loud AGN is, instead, very rare. And yet, the presence of an ionized, scattering medium is postulated by unification models for these sources, and in models for jet formation. Here we propose sensitive Chandra LETGS observations of 3C 445, a nearby bright Broad-Line Radio Galaxy with a line-dominated soft X-ray spectrum. For the first time in a luminous radio-loud AGN, it will be possible to resolve the soft emission lines, determining the kinematics and location of the photoionized gas, its role in jet collimation and thereby probe the differences in the circumnuclear environment between radio-loud and radio-quiet AGN.

Proposal Number: 10700125

Title: Short-time monitoring of extreme spectral variations in Seyfert 2s

PI Name: GUIDO RISALITI

We propose two 3 weeks monitoring campaigns of five 10 ks observations, of two Seyfert Galaxies, found in both reflection-dominated and transmission-dominated states in past observations. The aim is to detect such variations on time scales of a few days. A Chandra monitoring analogous to the ones proposed here, performed in 2006 on NGC 1365 provided a spectacular result: a spectral change from Compton-thin to Compton-thick and back to Compton-thin in four days. One more campaign completed just a few days before this deadline on UGC 4203 provided similar results.If found in other sources, these extreme variations would demonstrate that the thick absorber in Seyfert Galaxies is extremely compact (on the spatial scale of the broad line region).

Proposal Number: 10700149

Title: Exploratory Chandra observations of low-metallicity AGN candidates

PI Name: Trinh Thuan

Metallicity estimates of AGN generally range from solar to supersolar. This is because their massive, bulge-dominated galaxy hosts have processed much of their gas into stars by the present epoch. If AGN metallicity correlates with stellar mass, however, then low-metallicity AGN should reside in low-mass dwarf galaxies. Yet searches in low-mass galaxies have only turned up AGN with slightly subsolar metallicities, at best. So where are the low-metallicity AGN? We propose Chandra observations of four candidates discovered in a large sample of metal-poor dwarf galaxies in the SDSS (<0.1 solar). All are faint (M_g>-19.2), yet show strong broad Halpha (>3e41 erg/s, >2200 km/s) coming from very dense regions (>>1e4/cm3). Chandra will help to secure the AGN nature of these primordial analogues.

Proposal Number: 10700189

Title: A Co-ordinated Chandra, Suzaku, HST Campaign for NGC3227

PI Name: Martin Elvis

We propose a 200ksec LETGS/HRC observation of NGC3227, a bright, nearby AGN, coordinated with Suzaku monitoring and HST UV spectra. NGC3227 seems to have a distant, dusty, 'lukewarm' Warm Absorber (WA), AND a smaller, high ionization, WA. For these WAs an LETGS grating spectrum will determine: ionization parameter, NH, 'b'-parameter, metal ratios and dust-specific features. The WA location will be known from Suzaku monitoring; together Chandra and Suzaku observations determine the mass loss rate. A joint HST/COS UV spectrum gives absolute metallicity and velocity and covering factor. With the WAs well characterized, NGC3227 joins two other WAs to span M_BH - L/L_Edd space, allowing tests of AGN-galaxy feedback models.

Proposal Number: 10700214

Title: AN X-RAY MICROLENSING TEST OF THE AU-SCALE CENTRAL STRUCTURE OF THE QUADRUPLE QUASAR 2237+0305

PI Name: Shin Mineshige

We propose Chandra observations of the gravitationally lensed quasar Q2237+0305 during a microlensing event to reveal its AU scale central structure. The quasar is being monitored from the ground regularly to ascertain the onset of the event. As it occurs, we will measure X-ray spectral variations with Chandra and compare with those taken before and after the event. Since a small region of the quasar accretion disk is strongly magnified during the event, we will be able to limit the mass contained on scales of several AUs and to probe the physical properties of X-ray emitting gas in the vicinity of the black hole. Together with ground-based telescopes, we can resolve the quasar emission regions at multiple wavelengths. This provide a critical test of quasar accretion disk theories.

Proposal Number: 10700224

Title: Probing physical conditions in the extended emission-line regions of powerful radio galaxies: the case of 3C171

PI Name: Martin Hardcastle

Extended optical emission-line regions in which cold gas is ionized by the radio jets are common in high-redshift radio AGN. Our target, 3C171, is the best-studied low-redshift analog of those systems: a region of shock-excited, outflowing gas around the jets has been studied with optical and high-frequency radio polarization data. 'Snapshot' Chandra observations have shown that the environment of the radio galaxy, and potentially the medium responsible for the radio depolarization, are detectable in the X-ray. We propose follow-up Chandra observations that will measure the physical conditions in and around the radio source; coupled with our optical and radio data, this will give a complete picture of the dynamics and energetics of the outflow of cold and warm gas in this object.

Proposal Number: 10700228

Title: Deep ACIS-S imaging of two X-shaped radio galaxies

PI Name: Christopher Reynolds

X-shaped radio galaxies (XRGs) are often considered to be the smoking gun of a supermassive black hole merger, with the unusual radio morphology attributed to the rapid re-orientation of the AGN jets during the merger event. We request deep (100ks) observations of two XRGs; 4C+00.58 and J1043+3131. Our principal objective is to map the morphology of the hot interstellar/intragroup medium around these radio galaxies that has been previously discovered in our Cycle-9 pilot study, and hence test the "expanding backflow" model of XRG formation which remains a viable alternative to the merging black hole picture. The study proposed here will double the number of XRG that have been imaged deeply in the X-ray band, and provide the most compelling test yet of the backflow model of XRGs.

Proposal Number: 10700258

Title: Identifying High-Redshift X-ray Jets from Radio-Loud Quasars with Chandra

PI Name: William Brandt

We propose ACIS-S imaging observations of two luminous, radio-loud quasars at z = 3.6 and 4.3. Our Chandra snapshot observations of these targets revealed evidence for X-ray extension, and we aim to identify definitively whether these features are kpc-scale X-ray jets. This program should substantially increase the sample of z > 3.5 quasars with resolved X-ray jets, and we will determine the X-ray extent and morphology of each jet for comparison with VLA data. By comparing the X-ray-to-radio flux ratios of these high-redshift jets with those of closer jets, we will constrain jet X-ray emission mechanisms. These data will also allow effective investigation of intrinsic X-ray absorption in the core spectrum for one of our targets and constrain X-ray variability for both.

Proposal Number: 10700299

Title: Jets at Intermediate Redshifts: Shedding Light on Emission Mechanisms and Physics

PI Name: Rita Sambruna

We propose observations of a small sample of intermediate-redshift radio jets (2=3-4) tend to confirm the IC/CMB origin of the X-ray emission, the limited morphological information available due to the faintness of the radio emission prevents more detailed studies. Observations at intermediate z will bridge the gap, allowing us to study the role of both the increase of the CMB energy and intergalactic matter densities on the X-ray emission properties and physics of jets.

Proposal Number: 10700307

Title: Two to Tango? Binary Quasars, their Environments, and the Merger Hypothesis

PI Name: Paul Green

Merger/feedback scenarios linking AGN and galaxy evolution to cosmological structure formation seem wildly successful. Close quasar pairs, which are rare but show a significant excess over the extrapolated large-scale quasar correlation function, are the strongest candidates for merger triggering we have. But a competing theory posits that their excess is only due to their inhabiting locally overdense environments. To address this controversy, we propose to observe 9 close quasar pairs. Their X-ray luminosity, spectra, and broadband SEDs will be compared to hundreds of isolated SDSS quasars already imaged and analyzed. Proposed NOAO 4-meter imaging provides complementary tests for environmental overdensities.

Proposal Number: 10700401

Title: Mothering and smothering: AGN in merging galaxies

PI Name: Diana Worrall

We will study the role of early-stage galaxy mergers in triggering and smothering the AGN-induced ejection of radio plasma, an important heat source in the Universe. Our X-ray and radio observations will allow us to measure the energetics and dynamics of radio-plasma/X-ray interactions, determining the pressures in both components and detecting gas features (e.g., shocks, filaments) that have a morphological association with the radio structures and galaxy motions. We focus on systems whose known properties suggest they are least complicated and which will show different aspects of triggering and smothering.

Proposal Number: 10700465

Title: The nature of active nuclei in radio galaxies: observations of the 2Jy sample

PI Name: Martin Hardcastle

We propose Chandra observations that will provide a complete, unbiased sample of radio galaxies drawn from the 2Jy sample, which already has excellent radio, optical and mid-infrared data. Our primary goal is X-ray spectra of the active nuclei: we will detect or put strong upper limits on the heavily obscured continuum emission that indicates a radiatively efficient AGN, and combine this with the uniquely good data at other wavelengths to establish a definitive picture of the ways in which black-hole activity manifests itself in these objects. We will test models in which the optical line emission class indicates powerful, radiatively inefficient AGN. We will also constrain the hot-gas environments of our targets and test models that relate accretion mode and environment in radio AGN.

Proposal Number: 10700504

Title: The multi-faceted X-ray activity of low-redshift active galaxies

PI Name: Mark Birkinshaw

We propose ACIS-I observations of Chandra-unobserved low-redshift 3CRR active galaxies and their environments. The data will complete Chandra observations of 3CRR at z < 0.1, making the sample useful for statistical studies. Only Chandra can resolve the multiple components of these sources, as is needed for an improved understanding of source physics and gas heating. The imaging and spectroscopy of cores, jets, hot spots, and atmospheres will be of permanent legacy value. We will use the data to investigate particle acceleration, interactions between radio plasma and the ISM and IGM, the emission mechanisms of hot spots, and AGN fueling. Comparison with our complete Spitzer coverage and HST images will aid interpretation. The dataset will be made public immediately.

Proposal Number: 10700550

Title: Chandra ToO Observations of Flaring GLAST Blazars

PI Name: Greg Madejski

We propose for two 25 ks ToO observations of blazars (or any other high latitude source) undergoing an exceptional flare in the GLAST gamma-ray band. We intend to use Chandra only if other facilities such as RXTE or Suzaku are not sufficiently sensitive, or cannot reach the source because of the Solar angle or scheduling constraints; we estimate the probability of a Chandra trigger about 50 pct. The resulting X-ray data - both the spectrum and variability information - will be indispensable to deterine the emission mechanisms, and by extension, allow inferences about the structure of the sub-parsec jet, and connection of the jet to the accretion disk and the supermassive black hole.

Proposal Number: 10700575

Title: Feedback in Seyfert galaxies: shocks, jets and winds

PI Name: Judith Croston

Disentangling the feedback contributions from AGN outbursts, star formation and galaxy winds to the energetics of gas in galaxies, galaxy groups and clusters is a key problem in galaxy evolution. Recent work has shown that kpc-scale radio bubbles connected to an active nucleus can be found in a wide range of host-galaxy environments, including spiral galaxies. We recently carried out a Chandra observation of one such system NGC 6764, finding X-ray luminous hot gas associated with the radio bubbles. Here we propose to observe two further Seyfert galaxies with kpc-scale radio bubbles, NGC 3367 and Markarian 6, in order to determine whether shock heating is ubiquitous in these systems, and to disentangle the effects of AGN, star formation activity and superwinds.

Proposal Number: 10700584

Title: Deconstructing AGN X-ray Spectra - Time for a Paradigm Shift?

PI Name: Tracey Turner

We aim to detect and measure the ionization state and outflow velocities in the well-studied low-BH-mass AGN NGC 4051. We have been granted a 340 ks Suzaku observation to study continuum and low-resolution line spectral variability; HETG spectroscopy complements this by isolating narrow absorption lines arising from key zones of gas, allowing us to measure ionization, column and outflow velocities of the multiple ionized zones. A moderately ionized zone in particular can mimic the appearance of a broad Fe emission line but can be revealed by 6.5 keV Fe Kalpha absorption, for which there is already tentative evidence. A 320 ks HETG exposure will provide powerful diagnostic signatures across a wide range of ionisation. We also request HST time for tie-in UV spectroscopy.

Proposal Number: 10700652

Title: Luminous Compton-thick QSOs at z~1

PI Name: Roberto Gilli

Over the last few years, an increasing number of results have suggested that heavily obscured, Compton-Thick (CT) AGN are abundant both in the nearby and in the distant Universe. At high redshifts and luminosities, however, sampling the population of CT AGN is difficult because of their faintness and low density on the sky. We propose a program consisting of short exposures (10 ks each) to observe 16 luminous QSOs at z~1 which are likely to suffer from heavy obscuration. The targets have been selected from the SDSS DR6 based on their strong [NeV]3427 emission. The proposed observations will determine the average obscuration properties of these objects, placing constaints on the population of CT QSOs at z~1.

Proposal Number: 10700657

Title: Using Chandra to Understand the TeV Emission from M87

PI Name: Daniel Harris

With observational data from VERITAS, HESS, and MAGIC, it appears that there are TeV 'high states' for M87 which can last a few weeks and provide many nightly detections at a level significantly higher than the 'quiet state'. Because we model the TeV emission as IC scattering by the same electrons responsible for X-ray synchrotron emission, we expect that TeV variability will be mirrored in the UV and X-rays. To determine the location of TeV emission and to obtain quasi simultaneous photometry to refine sync/IC calculations, we request a Chandra TOO program on M87 to be triggered by the TeV 'high state' condition. We request a maximum of 90 ks, divided into 5ks observations so as to construct a lightcurve for comparison with those obtained by the Cherenkov observatories.

Proposal Number: 10700660

Title: Evolution of Activity in Massive Gas-rich Mergers: The X-ray Perspective

PI Name: Sylvain Veilleux

As the final element of QUEST, a multiwavelength program on local massive gas-rich mergers, we propose to obtain ACIS-S data on all z < 0.15 ULIRGs with no obvious signs of AGN activity in deep Spitzer MIR spectra but with reliable spectroscopically-determined host (hence black hole) masses. The main goal is to investigate the evolution of nuclear activity in advanced mergers beyond the first peri-passage. We wish to study in detail the basic physical processes involved in creating massive early type hosts, and feeding embedded massive BHs in major galaxy mergers. This is an important question since about 50% of cosmic star formation at high-z and most of the big BHs appear to be formed in this process. Here we first propose a snapshot survey of the 10 sources without any X-ray data.

Proposal Number: 10700662

Title: Testing the Radiative-Driving Hypothesis of Quasar Outflows

PI Name: Rajib Ganguly

Outflows are seen prominently in the UV spectra of Broad Absorption Line (BAL) QSOs. Radiatively-driven outflows predict that the velocity (vmax) should scale with UV luminosity (LUV). Observations show that LUV only provides a cap to vmax. One explanation is that the X-ray absorbing gas in an individual quasar provides a shield that regulates its radiative driving efficiency. That is, quasars with thick shields can accelerate gas to higher vmax. To test this hypothesis, we propose snapshot (8ks) ACIS observations of 12 carefully-selected BALQSOs to investigate the relationship between vmax and X-ray absorption, and thus the role of shielding in radiative acceleration.

Proposal Number: 10700664

Title: Exploring the X-ray - TeV connection in BL Lacs on short timescales

PI Name: Sarah Kaufmann

We propose to perform one ToO for a full night (30 ks) of simultaneous observation with Chandra and H.E.S.S., on a flaring TeV blazar with flux high enough to constrain both spectra on hour timescales or less. Our goal is to investigate with unprecedented detail the intra-night and sub-hour variability in TeV blazars, as strikingly revealed by recent H.E.S.S. observations on PKS 2155-304 (few minutes flux doubling timescales). The aim is to shed light on the origin of the gamma-ray emission and on the relation between X-ray and gamma-ray emissions.

Proposal Number: 10700666

Title: Completing a Flux-limited Survey for X-ray Emission from Radio Jets

PI Name: Herman Marshall

We propose to obtain high resolution X-ray images for a well defined complete sample of quasar jets. Selection is based on the flux density in extended emission which should give a sample that spans a wide range of jet physical conditions. We will find good targets for detailed X-ray imaging followup so that we can measure the spectral energy distributions and then test models such as the synchrotron and synchrotron self-Compton emission mechanisms. Shallow surveys provide an efficient use of Chandra observing time for this purpose because little time is given to targets that are too weak for effective followup. Furthermore, for a small initial observing time, it is more straightforward to estimate exposure times for followup observations.

Proposal Number: 10700667

Title: Probing X-Ray Jet Emission Mechanisms in a Complete Blazar Sample

PI Name: Preeti Kharb

We propose deep (70 ksec) followup Chandra X-ray observations and new HST WFPC2/F450W observations of two quasars belonging to the complete flux-limited MOJAVE Chandra blazar sample. These two quasars have HST WFPC2/F702W data available in the archive. Combining the existing optical and radio data with the new Chandra and HST data at an additional optical band we aim to construct asignificantly more accurate multi-waveband (four frequency) spectral energy distributions for distinct knots in the jets. This will serve as a first step towards resolving longstanding ambiguities surrounding the primary X-ray emission mechanisms in a well-defined sample of powerful FR-II class jets.

Proposal Number: 10700678

Title: The Circumnuclear X-Ray Environments of CSS Radio Sources

PI Name: Daniel Evans

We propose the first Chandra/ACIS-S observations of the kpc-scale circumnuclear environments in a sample of Compact Steep Spectrum (CSS) radio sources, the likely progenitors of powerful radio galaxies. Their small-scale radio ejecta mean we can simultaneously examine the roles of AGN photoionization and jet-environment interactions on gas both interior and exterior to the radio lobe. We will explore the relationship between the X-ray environment, extended [O III] NLR, and radio outflow. We will then (1) determine the role of jet-environment interactions in imparting energy into the ambient ISM, (2) assess the energetic contribution from photoionizing AGN radiation, and (3) compare the circumnuclear environments in CSS sources with those in other radio-loud and radio-quiet AGN.

Proposal Number: 10700684

Title: Chandra survey of Polar Broad Absorption-Line Quasars

PI Name: Kajal Ghosh

We have detected polar broad absorption-line quasars from their radio-core variabilities. Recent X-ray observations of two polar LoBALQSOs suggest that they may have different X-ray properties from other BALQSOs: their X-ray absorbing columns are much smaller compared to that of non-polar LoBALQSOs with Compton-thick absorbing columns and the polar LoBALQSOs may have different type of outflow. Here we propose snapshot survey (6~ks exposure each) of 10 polar BALQSOs to determine if this is the case. Determining if polar BALQSOs are qualitatively different from the rest of the BALQSO population would be a very significant result.

Proposal Number: 10700689

Title: Chandra X-ray Scrutiny of New Radio-Shy BL Lac Candidates

PI Name: Scott Anderson

BL Lacs are rare X-ray emitting AGN, oft-unified with FR I radio galaxies viewed along a jet. Despite decades of study it is still uncertain whether all BL Lacs are strong radio sources: venerable BL Lac samples include just dozens of objects, too few to test for an even rarer radio-quiet subset. But, recent large area surveys have found a few intriguing BL Lacs lying on the radio faint tail; SDSS alone provides hundreds of new BL Lacs, with several dozen potentially radio-shy cases. We propose brief Chandra images of 3 such BL Lac candidates having deep VLA data but lacking X-ray constraints. Chandra scrutiny is a prerequisite to claiming them as radio quiet BL Lacs; confirmation would provide fascinating challenges to our understanding of this peculiar AGN subclass.

Proposal Number: 10700699

Title: The Structure and Physics of the Youngest Radio Galaxies

PI Name: Eric Perlman

We propose to obtain X-ray images and spectra of two of the nearest and X-ray brightest compact symmetric objects. These objects are radio sources which have begun ejecting radio plasma within the last $\sim 10000 years$. The purpose of these observations is to discover their X-ray structure, measure their X-ray spectra and test the Wilson-Colbert hypothesis regarding the formation of radio-loud AGN. CSOs are ideal targets for this test because they are very small ($\sim 100pc$) and very young. By targeting the very nearest objects we assure ourselves of the highest possible physical resolution. We are particularly looking for binary black holes (possibly found for one of our objects already) and/or nascent NLRs.

Proposal Number: 10700750

Title: Mapping the Centaurus A Nuclear Region

PI Name: Margarita Karovska

We propose to carry out high-angular resolution HRC-I observations of the early-type galaxy Centaurus A containing the nearest radio-bright AGN, and map the circumnuclear X-ray emission within a radius of 3". Cen A provides a unique opportunity to carry out sub-arcsecond resolution X-ray imaging of the nuclear region, which will result in key constraints on the AGN unified model and the putative torus of gas and dust surrounding the nucleus and the accretion disk. Our goal is to confirm the possible detection of extended emission in the circumnuclear region using early HRC-I observations, obtain the first unambiguous X-ray image of a resolved torus structure in an AGN, and search for jet--environment interactions or AGN-photoionized gas in the circumnuclear regions.

Proposal Number: 10700854

Title: A Complete Census of AGN Activity in Luminous Infrared Galaxies

PI Name: David Alexander

We are undertaking a detailed study of AGN activity in Luminous Infrared Galaxies (LIRGs) at d<60 Mpc. We have Spitzer-IRS spectroscopy for our targets, providing a sensitive probe of AGN activity at mid-IR wavelengths, but only six of our 17 LIRGs have Chandra coverage, restricting crucial information on the X-ray properties of LIRGs. Here we propose for ACIS-S observations of the 11 LIRGs in our sample that currently lack Chandra constraints. Our aims are to (1) provide the most complete constraints on the properties of AGNs in LIRGs, (2) assess the fraction of distant AGNs that are being misclassified in the deepest X-ray surveys, and (3) identify the starburst galaxy X-ray power from X-ray binaries, hot interstellar gas, and supernovae in the LIRG population.

Proposal Number: 10700883

Title: Zeroing in on the sources of Ultrahigh Energy Cosmic Rays

PI Name: Glennys Farrar

Correlations have been observed between the highest energy cosmic rays and galaxies in the Veron-Cetty Veron catalog of Quasars and AGN. However only 14 of the 21 correlated VCV galaxies are optical AGN, and a correlation with luminous infrared galaxies has been found. This suggests the exciting possibility that UHECRs are produced by both AGN and systems associated with star formation such as GRBs or magnetars. A crucial question is therefore whether correlated galaxies which have not been identified as AGN, are in fact AGN. The Chandra observation will answer this question. Key information that will be determined by this observation is the X-ray luminosity and the spectrum of the correlated galaxies, to understand whether those which accelerate have unusual properties.

Proposal Number: 10700916

Title: Using Chandra and HST to Construct the First Detailed Timeline of Early-Type Galaxy Evolution

PI Name: Ann Zabludoff

While considerable effort has been devoted to statistical studies of the origin of the red sequence of galaxies, there has been relatively little direct exploration of galaxies transforming from late to early types. Such galaxies are identified by their post-starburst spectra, bulge-dominated, tidally-disturbed morphologies, and current lack of gas. We are constructing the first detailed timeline of their evolution onto the red sequence, pinpointing when star formation ends, nuclear activity ceases, globular clusters form, and the bulk of the merging progenitors' dust disappears. Here we propose to obtain HST imaging of nine galaxies, whose wide range of post-starburst ages we have precisely dated with a new UV-optical technique and for which we were awarded Spitzer time.

Proposal Number: 10700917

Title: WPVS 007: the little AGN that could

PI Name: Karen Leighly

Outflows are important components of AGN, potentially removing angular momentum, enriching the intergalactic medium, and potentially playing a key role in the evolution of galaxies. Yet their astrophysics is poorly understood. We propose an FUV observation of the Seyfert-luminosity AGN WPVS 007 (M_V=-19.7, z=0.02882) using COS, coordinated with a short Chandra observation. Observed to have a miniBAL with maximum velocity v_max~1000 km/s in an 1996 HST observation, it was discovered to have developed an additional BAL flow by the time of the FUSE observation in 2003. The BAL flow has maximum velocity of at least 6,000 km/s, and the unambiguous presence of PV indicates that it is very optically thick. (Truncated to conform with length limits required by Chandra RPS.)

Proposal Number: 10700920

Title: AO-10 Calibration Observations of 4U 1957+11

PI Name: CXC Calibration

These observations of the X-ray binary will be used to improve ACIS CC-mode calibration.

Proposal Number: 10700928

Title: AO-10 Calibration Observations of PKS2155-304

PI Name: CXC Calibration

We continue to monitor the build-up of contamination on ACIS with LETG/ACIS-S observations PKS2155-304. These observations are also used for internal cross-calibration as well as cross-calibration with XMM-Newton and Suzaku.

Proposal Number: 10700929

Title: AO-10 Calibration Observation of PKS2155-304 Near the Read-Out

PI Name: CXC Calibration

We continue to monitor the build-up of contamination on ACIS with LETG/ACIS-S observations PKS2155-304. These observations are also used for internal cross-calibration as well as cross-calibration with XMM-Newton and Suzaku.

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