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Proposal Number: 09700043

Title: NGC 1068: Photo-ionized gas in the nucleus, and ionization cone

PI Name: Claude Canizares

We request a total of 400 ksec of Chandra HETGS observations of the archetypal Seyfert 2 galaxy NGC 1068. The primary goal of these observations is to study the spatially extended photo-ionized emission line gas in the nucleus, and the ionization cone to the northeast. We will examine the Fe XXV lines, radiative recombination continua, He-like triplets and other emission lines to determine the ionization state of the gas. These observations will test the hypothesis that the extended emission is highly photo-ionized.

Proposal Number: 09700056

Title: LETGS Spectroscopy of the Narrow-Line Seyfert 1 Galaxy Arakelian 564

PI Name: Peter Predehl

LETGS Spectroscopy of the Narrow-Line Seyfert 1 Galaxy Arakelian 564 to study the warm absorber with its wealth of absorption features (lines and edges) as well as emission lines in the X-ray spectra.

Proposal Number: 09700061

Title: Chandra ACIS Snapshots of the Brightest Radio-Loud Broad Absorption Line Quasars in the SDSS

PI Name: Gordon Garmire

We propose a Chandra snapshot survey of 13 of the brightest radio-loud broad absorption line quasars (BAL RLQs) in the Sloan Digital Sky Survey (SDSS). These observations will more than triple the number of BAL RLQs with X-ray detections and will allow efficient investigation of the strength and characteristics of intrinsic X-ray absorption. Our sample of notably radio-loud high-ionization BAL quasars (displaying a wide range of outflow velocities and depths) will enable us to test correlations between radio, UV, and X-ray properties and constrain the nature of BALs in RLQs. We will also search for X-ray jets (some targets have extended radio structure) and identify promising candidates for follow-up X-ray and radio observations.

Proposal Number: 09700067

Title: Chandra follow-up observations of Swift/BAT unidentified sources: Searching for obscured type II quasars

PI Name: Peter Predehl

We propose 5 Chandra follow-up observations, of 5 ks each, of BAT unidentified survey sources. These sources are detected in the ongoing BAT survey using the Maximum Likelihood method (Ajello et al. 2007a, 2007b and Rau et al. 2007).

Proposal Number: 09700091

Title: Simultaneous Chandra, VLT, and APEX Observations of Sgr A*

PI Name: Farhad Yusef-Zadeh

We propose Chandra observations of X-ray flares from Sgr A*, in conjunction with near-IR and submm observations with an already approved observation with the ESO's VLT and APEX. We intend to measure simultaneously the spectral index distribution of flare emission in X-ray, near-IR and submm wavelengths, the time average flux and duration of flares, the statistics of flare activity and to confirm previously reported quasi-periodic variability. These measurements will have far-reaching implications for testing the inverse Compton scattering (ICS) and synchrotron models of low-luminosity flares onto and outflow from supermassive black holes, and constraining the inferred black hole spin.

Proposal Number: 09700098

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: 09700175

Title: Studying the Optical and X-ray Emission Regions of Quasar RX J1131-1231 by Monitoring Microlensing Events

PI Name: George Chartas

We proposal to apply the microlensing method to study the spatial structure of the optical and X-ray continuum emission regions of the quasar RX J1131-1231 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: 09700212

Title: Velocity Gradients in the Jets of BL Lac Objects

PI Name: Alan Marscher

We propose to observe the arcsec-scale jets of 2 BL Lac objects with highly relativistic jets (bulk Lorentz factor of 16) on parsec scales in order to determine whether a velocity gradient exists between the axis and edge of the jet and along the length of the jet. Models both for the morphology of jets in BL Lac objects and for the launching of the jet predict such gradients. If radio-selected BL Lac objects are end-on FR 1 sources, there should be strong X-ray emission from inverse Compton scattering of CMB photons along the highly beamed fast spine of the jet. The imaging observations with Chandra, HST, SST, and the VLA will therefore verify whether such a spine exists and on what length scale it decelerates to nonrelativistic speeds.

Proposal Number: 09700219

Title: Unraveling the accretion structure of the double-peaked emitter SDSS J2125-0813

PI Name: Iskra Strateva

We propose to obtain a 40ks X-ray spectrum of SDSSJ2125-0813 -- the most luminous (L[2-10keV]=6.4E+44ergs/s) radio-quiet quasar that shows signs of accretion-disk emission in the optical. A short exploratory Chandra observation of this object revealed tentative evidence for an unusually strong, ionized, broad Fe Ka line combined with little or no intrinsic absorption. The proposed Chandra observation will confirm or refute the presence of a relativistic Fe Ka line, the first such line to be detected in a double-peaked emitter. Alternatively, the detection of a strong narrow line will provide a rare example of strong Fe Ka emission in an active galaxy with quasar-like luminosity.

Proposal Number: 09700252

Title: Lower Luminosity AGNs at Cosmologically Interesting Redshifts: SEDs and Accretion Rates of z~0.36 Seyferts

PI Name: Sarah Gallagher

We propose a multiwavelength campaign to constrain the SEDs of Seyferts at z~0.36. This epoch, corresponding to a look back time of 4 Gyrs, is cosmologically interesting for studies of the coeval development of black holes and their host galaxy bulges. Our sample, comprising 24 Seyferts, has unprecedented high quality Keck spectroscopy and HST imaging already invested to extract host galaxy bulge properties, estimate black hole masses, and separate nuclear and host optical luminosities. To supplement and extend this successful program, we request 93 ks of Chandra time (to measure the shape and power of the AGN-only X-ray continuum), 11 hrs each of Spitzer and Gemini (to constrain the dust temperature), and 7 orbits of HST (to determine the nuclear luminosity for the final 7 objects).

Proposal Number: 09700284

Title: Coordinated Multiwavelength Observations of New TeV Blazars Detected by VERITAS

PI Name: Markus Boettcher

We propose a 40 ksec ACIS-S ToO observation on one out of a sample of 10 candidate blazars for TeV emission, currently on the VERITAS observing program. The Chandra ToO observations will be triggered following a detection by VERITAS, which in turn, may be triggered by an extraordinary optical flare. It will only be triggered if the source can not be observed through our approved XMM-Newton ToO. The observations will be coordinated with simultaneous monitoring observations at radio, near-IR, and optical frequencies. For the first time, simultaneous monitoring at MeV - GeV energies will be carried out by GLAST. The proposed campaign aims at the detection of new TeV blazars with meaningful multiwavelength data to allow detailed studies of their broadband spectra and variability.

Proposal Number: 09700302

Title: The inner kpc of NGC4151: the AGN-host interaction region in depth

PI Name: Giuseppina Fabbiano

We propose to observe the nearby Seyfert galaxy NGC4151 with HRC for 50 ks and ACIS-S 1/8 subarray for 200 ks, to study in detail the morphology and spectral properties - both continuum and line emission - of the circumnuclear X-ray diffuse emission, from ~100 pc to a few kpc from the SMBH. We will also study the XRB population of these regions down to flux limits consistent with those of Galactic XRBs, to explore the effect of the luminous AGN on the star-formation processes, of which these sources are an obscuration independent marker. The unprecedented view of the interaction of the SMBH winds with the surrounding ISM will generate strong physical constraints on the properties of this ISM, and will place tight constraints on nonthermal jet emission in low-power radio-quiet AGNs.

Proposal Number: 09700387

Title: A Simple Test of Quasar Outflow Models

PI Name: Frederick Hamann

Energetic outflows are important components of quasar environments. They give rise to a variety of UV absorption lines in quasar spectra and they are believed to originate from the inner accretion disk. In some sources, there is direct evidence for the UV lines forming in an outflow very near the central engine based on partial coverage of the background light source. However, in some of these same absorbers, there is also contradictory evidence for low densities that require extremely large distances (>10kpc to >100kpc) based on photoionization. We propose Chandra ACIS-S observations that will either resolve or confirm this contradiction and thereby test our understanding of basic outflow properties.

Proposal Number: 09700405

Title: Deconstructing the Accretion Disk Wind in Quasars

PI Name: Gordon Richards

Radiation and MHD driven accretion disk winds are reaching a level of maturity in explaining the observational signatures of quasars in the broad emission (and absorption) line regions. Further advancement of the models requires additional empirical input to provide observational constraints. One of the most robust indicators of a disk wind (other than broad absorption troughs) is the blueshift of the CIV emission line with respect to the systemic redshift. This proposal seeks to obtain good S/N (~100 counts) Chandra observations of 18 bright SDSS quasars (189.2 ks in total) in order to confirm a previous trend seen in joint spectral fitting of exploratory observations of large CIV blueshift quasars and to test radiation driven wind models for radio quiet quasars.

Proposal Number: 09700422

Title: Investigating the physics behind the X-ray / radio offset in 4C 74.26

PI Name: Mary Erlund

4C 74.26 is the largest known radio quasar; its southern hotspot complex contains the most luminous known X-ray hotspot and, intriguingly it also has the largest detected angular offset between its radio and X-ray hotspot peaks. We propose to image the X-ray hotspot complex, making use of Chandra's exquisite spatial resolution to resolve the X-ray hotspot(s), going deeper that existing archival data. In so doing we can determine whether the X-ray / radio hotspot offset is the result of inverse-Compton beaming of the cosmic microwave background in a decelerating flow (Georganopoulos & Kazanas 2003) or the dentist's drill effect (Scheuer 1982) enabling us to learn about the dynamics of the jet in more detail.

Proposal Number: 09700450

Title: X-Ray Emission in Radio-Quiet z>4 Quasars: A New Perspective on the AGN-Starburst-Connection?

PI Name: Dominik Riechers

We propose to investigate the nature of the extended X-ray emission detected toward the starbursting quasar BR1202-0725 (z=4.7), and to search for X-ray emission in BRI1335-0417 (z=4.4), with Chandra/ACIS. These sources are the only unlensed z>4 AGN-starburst systems that are resolved in molecular gas (CO), FIR and radio continuum emission. Shallow archival ACIS observations of BR1202 show two components (X1/X2). X1 is coincident with the optical quasar, and shows tentative evidence for a radio-quiet X-ray jet emerging from the AGN. X2 is only tentatively detected, which would be first evidence for an AGN. We here propose to confirm both tentative results in BR1202, and to obtain first X-ray observations of BRI1335.

Proposal Number: 09700467

Title: A Chandra survey of IMBH AGNs with low Eddington ratios

PI Name: Weimin Yuan

Intermediate mass black holes (IMBH) are an important class of objects. Interesting results have been obtained recently from a study with Chandra on a sample of IMBH AGN by Greene & Ho (2007, ApJ, 656, 84), which comprises mostly objects accreting at relatively high Eddington ratios. However, little is known about their low accretion counterparts as a class. We propose to observe a well defined, nearest sample of eight IMBH AGN (black hole masses $<10^{6}M_{\odot}$) with the least estimated Eddington ratios (0.01-0.1), which were discovered in our recent work. We aim at detecting their X-ray emission in order to secure their low accretion nature. This work complements that by Greene & Ho (2007) by extending Eddington ratio into a previously unexplored region in the parameter space.

Proposal Number: 09700477

Title: Dissecting Accretion Disks

PI Name: Christopher Kochanek

We will use microlensing, where the stars in a lens galaxy magnify the accretion disk of a lensed quasar, to measure the sizes of the X-ray emission regions of 6 gravitationally lensed quasars with well-sampled optical light curves. For RXJ1131-1231 and Q2237+0305, where we have already measured the average 0.4-8 keV band X-ray size to be comparable to the inner edge of the accretion disk, we will use longer observations in order to measure the X-ray energy dependence of the size. For PG1115+080 and HE1104-1805, we will extend their X-ray light curves to get an accurate 0.4-8 keV size measurement. For the last two systems, QJ0158-4325 and SDSS1004+4112, we will evaluate whether they are good candidates for measuring the size of the X-ray emission region with microlensing.

Proposal Number: 09700482

Title: Orientation effects in the X-ray and multi-wavelength properties of high-z, 3CRR quasars.

PI Name: Belinda Wilkes

We propose X-ray observations of 24 sources to complete a subset of 38 radio-lobe-selected, 3CRR massive radio galaxies in the redshift range 1\leq z \leq 2. We will measure the strength of the nuclear activity and study the relation of X-ray flux and spectral hardness to orientation, estimated from the radio core-dominance. In combination with the rich, multi-wavelength dataset for this inclination unbiased sample (to include Spitzer 3.6$-$70$\mu$m photometry), we will test AGN Unification at these redshifts. SED fitting will also provide constraints on models for the obscuring material, allow us to estimate the relative numbers of obscured and unobscured quasars and to quantify selection effects likely to be present in X-ray samples due to orientation.

Proposal Number: 09700497

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

PI Name: GUIDO RISALITI

We propose two ~3 weeks monitoring campaigns consisting of five 10 ks observations each, of two Seyfert Galaxies which were observed both in reflection-dominated and in transmission-dominated states in past observations. The aim is to detect such dramatic variations on time scales of a few days. A Chandra monitoring campaign 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. 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: 09700570

Title: Shock-heating by double-lobed radio sources in spiral galaxies

PI Name: Judith Croston

Shock heating by radio galaxies is thought to be an important means of transferring energy from active galactic nuclei to their environments. With recent Chandra observations, we have found evidence for strongly shocked gas surrounding two nearby, low-power radio galaxies, Centaurus A and NGC 3801, with large amounts of energy transferred from the AGN to the galaxy ISM in these systems, which will permanently increase the gas entropy. Although these two known examples of strong shocks both occur in elliptical galaxies, similar radio sources are found in a range of host galaxy types. To investigate the range of environments in which radio-galaxy shock heating can be important, we propose to observe three small, overpressured, double-lobed radio sources in nearby, active spiral galaxies.

Proposal Number: 09700606

Title: A Chandra Survey of Nearby X-shaped Radio Galaxies

PI Name: Christopher Reynolds

The unusual morphology of winged or X-shaped radio galaxies (XRGs) has been attributed to rapid changes in the spin axis of the jet-producing black hole during the merger of two supermassive black holes (SMBH). However, an alternative scenario posits that the wings are due to hydrodynamic blow-out of the (normal) radio-galaxy back-flow along the minor axis of a non-spherical ISM distribution. We plan to test the backflow model in a sample of nearby XRGs by correlating the minor axis of the ICM distribution with the radio-wings. Here, we propose the first stage of this program - a Chandra survey of all previously unobserved XRGs within z=0.1 (10ks observations of 14 objects). The results of this survey will be used to select optimal sources for detailed investigation in future cycles.

Proposal Number: 09700655

Title: NGC 4388 the Last Remaining Source - Chandra HETG Constrains on the Fe K line region

PI Name: Richard Mushotzky

High spectral resolution x-ray observations of AGN in the Fe K band have been critical for a set of important discoveries including ionized outflowing absorbers, Compton scattering shoulders on the Fe K lines, strong tests of the broad lines in AGN, and the dynamics of the Fe K line region. Thus high to moderate S/N, high resolution x-ray spectra are vital for understanding the geometry of the central regions. Most archival Chandra HETG observations of AGN are severely hampered by low S/N and to date there have been only two 'good' S/N grating observations of Seyfert IIs in the Fe K line region. We propose to obtain HETG for the only remaining object, NGC 4388, that is bright enough to get high S/N observations in the Fe K band in less than 300 ks .

Proposal Number: 09700656

Title: THE NATURE OF ENERGY TRANSPORT AND PARTICLE ACCELERATION IN THE TRANSITIONAL FRI/FRII RADIO GALAXY 3C 288

PI Name: Daniel Evans

We propose a 40-ks ACIS-S imaging observation of 3C 288, the prototypical example of a `jetted double' radio galaxy, which displays an unusually powerful, dissipative (FRI-like) radio jet and counterjet, but FRII-like large-scale radio features. Our observations have two distinct science goals: (1) to study the hot-gas environment of 3C 288, in order to establish how the thermal atmosphere influences the propagation of the radio jet, and what its role is in governing the transitional FRI/FRII morphology of the radio outflow, and (2) to examine the methods of particle acceleration and energy transport in a dissipative jet and counterjet 100 times more radio luminous than any known FRI jet.

Proposal Number: 09700701

Title: The Chandra view of NGC~3621: A bulgeless galaxy hosting an AGN?

PI Name: Mario Gliozzi

We propose to observe for 25 ks the nearby bulgeless galaxy NGC3621, which is optically classified as a normal galaxy but has recently been discovered by Spitzer mid-IR spectroscopy to contain an AGN. The unique capabilities of Chandra will be exploited to: disentangle the different components contributing to the X-ray emission and perform spatially-resolved spectroscopy; estimate the bolometric luminosity of the nuclear region; study the X-ray variability and put constrains on the black hole mass; investigate the circum-nuclear spatial and spectral properties to constrain the fuel reservoir. The proposed pilot study will open up opportunities to study the characteristics of the largely unexplored low black hole mass regime and the low mass end of the M_BH-sigma relation.

Proposal Number: 09700736

Title: Surveying X-ray Jets in Superluminal Blazars

PI Name: Matthew Lister

We propose a survey to search for X-ray emission associated with powerful FR-II jets in radio-loud AGN. Our sample is drawn from the MOJAVE program, which is currently studying the spectral and evolutionary properties of the 133 brightest and most compact AGN in the northern sky. Using the parsec-scale Lorentz and Doppler factors derived from our VLBA observations, we will evaluate current models for kiloparsec-scale X-ray jet emission, and address the longstanding question as to where deceleration is occurring in powerful extragalactic jets. All 32 AGN in our survey have extended jets at radio wavelengths, and 12 of 18 have been detected in X-rays with archival observations. We propose to obtain 10 ksec ACIS-S integrations of the 14 remaining AGN not yet observed with Chandra.

Proposal Number: 09700745

Title: Towards a Complete Sample: 3CR Extragalactic Radio Sources with z < 0.3

PI Name: Daniel Harris

In the last decade we performed a series of HST snapshot surveys of the 3CR sample that proved to be one of the most productive HST programs. As the completeness of high resolution X-ray observations, crucial for all multiwavelength analyses, lags far behind, we propose a Chandra snapshot survey of all unobserved 3CR sources with z<0.3: half now; half next year. An integration time of 8ks each will provide the data quality well suited to address the nature and propagation of jets, the physics of the environment, and will be relevant to evaluate the AGN unified models. The observations will also provide a versatile, complete, and uniform database that will be a valuable resource for the astronomical community, and since it is designed as a 'legacy' program, we waive proprietary rights.

Proposal Number: 09700792

Title: X-ray properties of compact CSS quasar with BALs - 1045+352

PI Name: Magdalena Kunert-Bajraszewska

We propose a 5 ksec observation with Chandra ACIS-S to detect for the first time an X-ray emission from the high ionization broad absorption line (HiBAL) compact steep spectrum (CSS) radio-loud quasar 1045+352. The X-ray information is critical to studies of the environment of BALQSOs. Radio-loud BALs have important additional information about their orientation based on the radio morphology, but they are rare. Only a handful of radio-loud BALs observed in X-rays so far indicating their high intrinsic absorption columns. The proposed target has a deep radio data and known optical spectrum. The new X-ray Chandra data will put a stringent limit on the absorption column by direct measure of the absorption in the spectrum or suppression of the predicted X-ray flux.

Proposal Number: 09700908

Title: Monitoring the Giant Flare of HST-1 in the M87 Jet

PI Name: John Biretta

(Abridged)During 2002, HST and Chandra monitoring of the M87 jet detected a dramatic flare in knot HST-1 located ~1" from the nucleus. Its optical brightness eventually increased seventy-fold and peaked in 2005; the X-rays show a similarly dramatic outburst. In both bands HST-1 is still extremely bright and greatly out-shines the galaxy nucleus. To our knowledge this is the first incidence of an optical or X-ray outburst from a jet region which is spatially distinct from the core source; this presents an unprecedented opportunity to study the processes responsible for non-thermal variability and the X-ray emission. We propose six epochs of HST flux monitoring during Cycle 16, as well as seven epochs of Chandra/ACIS observation (5ksec each, six Chandra epochs contemporary with HST).

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