Hosted by the Chandra X-ray Center

Name	Institution	Title	Abstract	Session
James Aird	Imperial College London	Faint end of the AGN x-ray luminosity function at z=3	We combine Lyman-break galaxy selection with deep Chandra x-ray data to efficiently select AGN at redshift z ~ 3. 21 AGN are discovered in 4 fields (Hubble Deep Field-North, Groth-Westphal Strip, Lynx and LALA CETUS). This sample is used to determine the faint end of the x-ray luminosity function at z ~ 3, carefully considering corrections for incompleteness in both the x-ray data and Lyman-break selection. We find a significantly steeper slope for the faint end than other work, indicating that the number density of moderate luminosity AGN at high redshift may have previously been underestimated.	P90
Tom Aldcroft	Harvard-Smithsonian Center for Astrophysics	Yaxx: Yet Another X-ray Xtractor	Yaxx is a Perl script that facilitates batch spectral processing of X-ray data. It includes automated spectral extraction, fitting, and report generation. The primary emphasis is on having an easily used tool that can be run without requiring an extensive learning curve. However, for those with the motivation, yaxx is highly configurable and can be customized to support complex analysis. Yaxx has been used extensively with Chandra data and a newly developed thread for XMM processing is now available. A modular software design allows for multi-mission support and user customization of the data processing flow.	P55
Amy Barger	University of Wisconsin-Madison	Extragalactic Surveys	I will review our current understanding of the history of supermassive black hole accretion from deep and wide-area X-ray surveys. I will use these data to compute the growth of the supermassive black hole mass density and compare it with the locally determined values.	O1
Volker Beckmann	NASA / Goddard Space Flight Center	The INTEGRAL 20-40 keV AGN Survey and Luminosity Function	We have compiled a complete extragalactic sample based on ~25,000 deg^2 to a limiting flux of 3 x 10^-11 ergs cm-2 s-1 (~7,000 deg^2 to a flux limit of 10^-11 ergs cm-2 s-1) in the 20 - 40 keV band with INTEGRAL. The flux-number relation is best described by a power-law with a slope of alpha = 1.66 +/- 0.11. We present the first AGN luminosity function above 20 keV. The results are consistent with those derived in the 2 - 20 keV energy band and do not show a significant contribution by Compton-thick objects.	O5
Niel Brandt	The Pennsylvania State University	Deep-Survey Constraints on X-ray Outbursts from Stellar Tidal Disruptions	Transient X-ray outbursts from galactic nuclei are likely caused by inevitable fueling events of supermassive black holes when a star or gas cloud is tidally disrupted and partially accreted. They may be a primary fueling mechanism for moderate-luminosity active galaxies. We present new constraints on the rate of such outbursts, utilizing the multi-epoch nature of the Chandra Deep Fields. Specifically, we constrain outbursts with harder X-ray spectra, higher redshifts, and lower X-ray luminosities than in our past work. We also discuss future plans and implications for the Black Hole Finder Probe, Lobster, eROSITA, LSST, and JDEM.	O5
Marcella Brusa	MPE - Max Planck Institut fuer Extraterrestrische Physik	The AGN content of the COSMOS: the XMM-Newton view	The XMM-Newton wide-field survey in the COSMOS field (XMM-COSMOS) is expected to be an important step forward in the study of the physics and evolution of AGN, especially for what concern high redshift obscured quasars. I will discuss the survey strategy and the main scientific objectives expected from the full exploitation of the truly multiwavelength dataset available (including HST, NIR, Spitzer and VLA data). I will also present the most important results obtained from the analysis of the first year XMM-Newton observations. In particular, I will concentrate on the multiwavelength properties of about 1400 X-ray sources detected over an area of ~2 deg^2, and I will show a few examples on how the combined use of different datasets is crucial to fully characterize the AGN source population.	O8
Francisco J. Carrera	Instituto de Fisica de Cantabria (CSIC-UC), Spain	Obscured and unobscured growth of supermassive black holes from the XMM-Newton Medium sensitivity Survey	We report on the current status of the XMM-Newton Medium sensitivity Survey, where we have identified the sources responsible for 50% of the accretion history in the Universe. This sample outnumbers previous medium X-ray surveys. We will discuss source counts, angular clustering, identifications, and X-ray spectral properties. Unobscured objects still dominate at these fluxes, but obscured sources become increasingly important at fainter fluxes. The X-ray-to-Optical flux ratio appears to be a good (but not perfect) discriminant between obscured and unobscured objects. Preliminary results confirm the presence of Fe-K emission in the stacked X-ray spectra of obscured and unobscured AGN.	O2
Francesca Civano	INAF--OAB & Bologna University	Multiwavelenght properties of elusive AGNs: X-EROs and XBONGs	Extensive programs of follow--up observations of sources detected in both deep and shallow X--ray survey (Chandra Deep Fields, HELLAS2XMM and COSMOS) have revealed a complex nature for the hard X--ray source population. The large database of these surveys offers a unique possibility to select statistically relevant samples of AGN characterized by extreme properties either in the X--rays or in the optical/near--infrared bands or boths, and to investigate their multiwavelength spectral energy distributions (SEDs). I will present the results of a multiwavelength study of X--ray sources selected on the basis of their extreme X-ray to optical properties, i.e. X-ray bright Optically Normal Galaxies (XBONGs) and X-ray emitting Extremely Red Objects (X-EROs). I will also discuss the results about the SED fitting and the morphological analysis of Quasar host galaxies for both classes of sources.	P180
Alison Coil	University of Arizona	Clustering of AGN and QSOs at z=1	Using galaxies from the DEEP2 Redshift Survey and AGN from the AEGIS/Chandra survey and QSOs from SDSS, I present the cross-correlation function of AGN/QSOs and 'normal' galaxies at z=1. Using the known clustering of DEEP2 galaxies, this leads to an estimate of the bias and typical host dark matter halo mass of AGN/QSOs as a function of X-ray luminosity, which constrains AGN formation models.	O6
Andrea Comastri	INAF - Osservatorio Astronomico di Bologna	Everything you always wanted to know about X-Ray Background but were afraid to ask	After a review of AGN synthesis models for the XRB I will discuss the multiwavelength properties of the XRB sources with special enphasys on peculair/extreme objects such as EROs EXOs XBONG and Compton Thick AGN. The wavelength dependence of selection criteria to obtain an almost complete census of accreting SMBH will be critically discussed.	O2
Jennifer Donley	University of Arizona	X-ray Properties of Spitzer-Selected AGN	Hard X-ray selection is generally considered the most efficient and complete way to select AGN. Even the deepest X-ray surveys, however, can miss heavily obscured AGN, which are predicted in significant numbers by models of the X-ray background. We present results of a Spitzer mid-infrared search for AGN in the Chandra Deep Field-North. Approximately 50% of the Spitzer-selected AGN are not readily detected in the X-ray, suggesting that they are either highly obscured or intrinsically X-ray weak. We discuss the properties of this AGN sample and its relation to the X-ray--selected population.	O10
Megan Eckart	Caltech	Recent Results from the SEXSI Survey: Comparison of AGN Selected by Chandra and Spitzer	We present the mid-IR properties and SEDs of spectroscopically-confirmed hard X-ray sources from five moderately-deep (50 - 200 ks) Chandra fields. These sources, identified in the SEXSI (Serendipitous Extragalactic X-ray Source Identification) survey, include (1) X-ray luminous, narrow-lined quasars; (2) X-ray bright, optically-normal galaxies (sources which appear inactive at optical wavelengths but reveal the presence of an active nucleus at X-ray energies); and (3) optically-faint X-ray sources which currently lack spectroscopic classification and are likely to be either at high-redshift, or heavily-obscured. In addition, we investigate the X-ray properties of mid-IR-selected AGN by performing a stacking analysis of sources undetected in X-rays in the Spitzer fields.	O10
Martin Elvis	Harvard-Smithsonian Center for Astrophysics	1. The Chandra COSMOS Survey 2. Compton-thick & Compton-thin AGN: Two different origins	1. The Chandra COSMOS Survey has just been approved as a Very Large Program for Cycle 8. C-COSMOS surveys the central square degree of the COSMOS field to 200ksec depth, a total of 1.8Ms. The survey science and strategy will be discussed. 2. Evidence that Compton-thick and Compton-thin obscured AGN have two physically different origins on different scales are presented and the implications for surveys and AGN evolution are discussed.	P10
Taotao Fang	UCB	Chandra Observation of DEEP2 Galaxy Groups and Clusters	I will present a 200 ksec Chandra observation of seven spectroscopically selected, high redshift (0.75 < z < 1.03) galaxy groups and clusters discovered by the DEEP2 Galaxy Redshift Survey in the Extended Groth Strip (EGS).	P340
Alexis Finoguenov	UMBC/MPE	Statistics of galaxy groups in ultradeep XMM surveys.	We discuss the results of the X-ray search and optical identification of galaxy groups in several ultradeep XMM fields: COSMOS, SXDS/UDS, CDFS and CDFN, detecting a total number of 200 of groups and clusters of galaxies with identifications achieving a z of 1.5. A statistical description of the survey in terms of the cumulative log(N>S)-log(S) distribution compares well with the previous results, although yielding a somewhat higher number of clusters at similar fluxes. For the probed luminosity range of 8e42-2e44 ergs/s, these surveys are in agreement with and adds significantly to the existing data on the cluster luminosity function at high redshifts and implies no substantial evolution at these luminosities to z=1.3.	O7
Fabrizio Fiore	INAF-OAR	The multiwavelengh survey of the ELAIS-S1 field	Both X-ray, optical and infrared observations are needed to provide a full census of AGN. They can be used to select samples of today still elusive Comptonthick AGNs. Deep surveys in these three wide bands are a key ingredient to obtain an unbiased AGN "bolometric" luminosity function. The central 0.6deg2 region of the ELAIS-S1 field is one of the few fields with deep X-ray (XMM, Chandra), optical (B,V,R,I,z, VLT-VIMOS and FORS2 spectroscopy), near infrared (J,K) and mid-infrared (IRAC, MIPS) coverage. It is therefore particularly well suited to test strategies to find both unobscured and moderately obscured AGN shining in X-rays and highly obscured AGN with faint X-ray emission but shining in the infrared. These strategies will then be applied on wider fields like the COSMOS field as soon the Spitzer and Chandra coverages will be ultimated.	O8
Willam Forman	Smithsonian Astrophysical Observatory - CFA	XBONGS in the XBootes Field	X-ray Bright Optically Normal Galaxies (XBONGS) have X-ray luminosities characteristic of accretion onto a SMBH, but lack the optical emission lines generally expected for AGN. We have analyzed a sample of 258 XBONGS detected in the XBootes Survey using X-ray, optical, infrared and radio observations. We find that XBONGS are not a single class of object, but fall into four categories -- red early-type galaxies, blue ellipticals, spiral/irregular galaxies and galaxies with AGN colors. We compare the luminosities, colors, X-ray spectra, and Eddington ratios of the XBONGS with those of narrow and broad-line AGN.	O4
Harold Francke	Universidad de Chile	Clustering of z=3 AGN in MUSYC-ECDFS	The Multiwavelength Survey by Yale/Chile (MUSYC) covers 1.2 square degrees of sky to U,B,V,R = 26 and K = 22 (AB), and includes the Extended CDF-S field, home of the largest Chandra survey ever conducted at its depth (0.3 square degrees and 228 ks). The X-ray catalogs of this field (Virani et al. 2006, Lehmer et al. 2005) reveal more than 700 Active Galactic Nuclei (AGN). We used the deep optical catalogs to apply the Lyman-Break technique, which yielded a sample of 84 AGN at 2.7 < z < 3.7. We performed a cross-correlation clustering analysis on these AGN and a sample of 1400 Lyman Break Galaxies at z~3. Here we present results on the clustering amplitude, estimates of the dark matter halo masses and number densities of z~3 AGN, and a measurement of the duty cycle for accretion by the SMBH hosted by these AGN.	P40
Stephan Frank	The Ohio State University, Department of Astronomy	The sources of the CFD-N - classification schemes, absorption estimates and broadband SEDs	We have developed a classification scheme for the sources of the CDF-N with known redshifts based upon the visual appearance of their broadband SEDs. The observed X-ray column density distribution for the complete sample of AGN shows a significant rise of the number of sources with N_H > 10^22.5 cm-2 when we include objects fainter than f_0.5-8.0 keV = 3.0 x 10^-15 erg s-1 cm-2. We argue that the ratio of X-ray absorbed to unabsorbed AGN remains constant with redshift, but not with luminosity. The comparison of the X-ray column density estimates with N_H, obtained by fits to the broadband NIR-UV SEDs, validates our classification scheme, and allows for placing constraints on unification models.	O2
Antonis Georgakakis	Imperial College	The environment of AGN at z~1	I will present results on the environment of X-ray selected AGN at z~1 using data from the Extended Groth strip International Survey (AEGIS) which combines (among others) deep (200ks per field) wide-area (0.5deg2) Chandra observations with extensive optical spectroscopy to R~24mag. The 3-D information is exploited to quantify the local density in the vicinity of an X-ray source by measuring the projected surface density of galaxies within a radius defined by the 3rd nearest neighbour. The main result is that X-ray selected AGN at z~1 avoid underdense regions at the 99.89% confidence level. Moreover, although the overall AGN population shares the same (rich) environment with optical galaxies of similar U-B and M_B, there is also tentative evidence (96%) that AGN with blue host-galaxy colors (U-B<1) reside in denser environments compared to optical galaxies. The results above can be understood as a consequence of the whereabouts of massive galaxies, capable of hostin! g supermassive black holes at their centers, with available cold gas reservoirs, the fuel for AGN activity. At z~1 an increasing fraction of such systems are found in dense regions.	P140
Ioannis Georgantopoulos	National Observatory of Athens	SHEEP2: A search for obscured AGN with XMM in the hardest band (7.5-12 keV)	We present initial results on our ultra-hard (7.5-12 keV) selected sample from the XMM Serendipitous Source Catalogue (SSC-1XMM). We find 17 sources down to have a flux of 10-13 cgs. The sample has a median redshift of 0.29. We find a number of high X-ray to optical flux ratio objects (log(fx/fo)>1) with four of these not having an optical counterpart down to B=21. The hardness ratio analysis indicates that most of the sources are unobscured.	P100
Marat Gilfanov	MPA, Garching	X-ray binaries and CXB.	We discuss contribution of X-ray binaries to the Cosmic X-ray Background. We show that given the cosmic star formation history and Lx-SFR relation for high-mass X-ray binaries, their contribution to the CXB energy flux in the 2-10 keV band can be as large as ~5%. A similar estimate for low-mass X-ray binaries gives an upper limit of a few per cent.	O4
Roberto Gilli	INAF-Osservatorio Astronomico di Bologna	The spatial clustering of X-ray selected AGN	We discuss the 3D clustering properties of AGN selected by X-ray surveys with different area and sensitivity. The measurements performed in the 0.1 deg2 Chandra Msec Fields are compared with those obtained in the 0.4 deg2 CLASXS and 81 deg2 NEP surveys. We also present preliminary results on the spatial clustering of ~300 AGN selected in the 2 deg2 XMM-COSMOS field, where a highly significant (~8sigma) clustering signal has been detected. The issue of cosmic variance is discussed. Finally, we investigate the relation between AGN clustering amplitude vs X-ray luminosity, redshift and obscuration.	O6
Percy Gomez	Gemini Observatory	First Results of an optically blind Sunyaev-Zeldovich Cluster Survey	We will present the first results of an optically blind Sunyaev-Zeldovich Cluster Survey carried out with the ACBAR bolometer array at the South Pole. Cluster candidates detected by the ACBAR array were verified by XMM-Newton and Chandra X-ray observations and by optical imaging and spectra.	P320
Paul Green	SAO	X-ray Spectral Properties of Broad Line AGN in the SDSS/ChaMP	AGN unification models spawned in the optical are now confronted with multiwavelength data that break the simplest Type I/II dichotomy. For instance, some broad emission line (optical Type I) AGN (BLAGN) are found to show significant X-ray absorption, and some narow line AGN (NLAGN) show none. Some of the absorbed BLAGN are explained as BALQSOs, but some are not. We cross-correlate the largest intermediate depth Chandra X-ray survey, the ChaMP, with a new SDSS photometric quasar catalog (extending to fainter mags and larger populations than the spectroscopic sample), and study the X-ray spectral properties of luminous broad line quasars. This constrains the absorbed fraction, identifies new BALQSO candidates, and tests claims of decreased absorption with increasing luminosity. We also contrast the X-ray spectral properties of this sample with those of an X-ray-selected BLAGN sample from the ChaMP.	P50
Josh Grindlay	Harvard	BAT Slew Survey (BATSS): Extending GRBs and AGN Flares to EXIST	We are implementing a survey using Swift/BAT event mode data from the ~60 "target slews" per day vs. the previously available ~3 GRB slews per week. This will increase BAT coverage and sensitivity for high z GRBs as well as AGN flares. Analysis of available GRB slews shows that due to averaging of detector and sky systematics, the sum of slews are appreciably more sensitive than pointed exposures of the same total time. BATSS will search for short duration flares of AGN (~1-10h), as expected from Blazars, and test scanning coded aperture imaging as proposed for EXIST.	P300
Heng Hao	Harvard University	AGN SEDs in COSMOS Survey	The early result of the AGN (mainly type I) spectral energy distributions (SEDs) in the COSMOS survey is showed in the poster.	P20
Ryan Hickox	Harvard-Smithsonian Center for Astrophysics	A population of mid-infrared selected, obscured AGN in the Bootes field	We analyze an infrared-selected sample of ~1500 active galactic nuclei (AGN) at redshifts 0.7 < z < 3 from the 9 deg^2 wide-field multiwavelength survey in Bootes. Data are taken from the Spitzer IRAC Shallow Survey, Chandra XBootes survey, NOAO Deep Wide Field Survey, and MMT/AGES survey. We classify the IR-selected AGN as Type 1 (unobscured) and Type 2 (obscured) based on their mid-IR and optical luminosities. We find ~700 Type 2 objects, and show that their multiwavelength properties are consistent with AGNs having N_H 3x10^22 cm-2, bolometric unabsorbed luminosities L_bol 10^44-10^46 ergs s-1 and L_bol/L_Edd 0.01-1. These Type 2 AGN represent one of the largest samples of distant, obscured AGN identified to date.	O10
Ann Hornschemeier	NASA GSFC	Deep X-ray Survey of the Coma Cluster with XMM-Newton	We present some preliminary results on a 220~ks survey of an off-center region in the Coma cluster. These observations are sensitive to ~10^39 erg s-1, allowing us to probe the X-ray emission from normal galaxies fainter than the Milky Way and construct an X-ray luminosity function. This represents a major step forward in characterizing the high energy emission of lower-luminosity galaxies in cluster/group environments. We also report on a major multiwavelength campaign to study the Coma cluster which includes Spitzer, GALEX, and HST data.	P370
Daniel Hudson	Argelander Insititute for Astrophysics - Bonn University	The Chandra Follow-Up Of The HIFLUGCS Sample - An Analysis Of The Cores Of All 64 Clusters.	The HIFLUGCS sample is a complete, flux-limited sample of the 64 X-ray brightest clusters outside of the galactic plane. The primary purpose of studying this sample is to provide a local cluster mass function which can be used to constrain cosmological parameters. We present the Chandra follow-up, which includes all 64 clusters, to the original analysis of this sample In this poster we focus on the analysis of the central density peaks of the clusters in the sample. Using high quality Chandra data we determined central temperature, density, entropy, and cooling time. We find that 46 of the clusters have central cooling times shorter than 7.7 Gyr, with a surprising 31 clusters having a central cooling time shorter than 1 Gyr. The high number of clusters with such cooling times implies that the main mechanism for quenching cooling cannot heat cluster cores above a cooling time of ~1 Gyr. Moreover, it implies that clusters with cooling times ~1 - ~7 Gyr either have not yet cooled to point of needing to be reheated or have been reheated by a different mechanism.	P310
Tesla Jeltema	Carnegie Observatories	The Evolution of X-ray Luminous Groups of Galaxies	We have undertaken a multiwavelength project to study the relatively unknown properties of groups and poor clusters of galaxies at intermediate redshifts. The full sample includes nine X-ray selected groups with redshifts between 0.2 and 0.6, and our follow up includes observations with XMM, HST, Gemini, and Keck. The X-ray properties of these systems are generally in good agreement with the properties of low-redshift groups. They appear to follow the scaling relations between luminosity, temperature, and velocity dispersion defined by low-redshift groups and clusters. We also find indications of excess entropy in these systems over self-similar predictions out to large radii. However, the properties of the group galaxies, in particular the central galaxies, show them to be less evolved than similar groups at low-redshift. Roughly half of our intermediate-redshift groups do not have a dominant central elliptical galaxy (BGG), and three of the four BGGs contain mult! iple luminous nuclei indicating recent merging.	O7
Matthias Kadler	NASA/GSFC	An X-ray Spectral Survey of Radio-Loud Core-Dominated AGN	I will discuss the X-ray properties of MOJAVE, the so far largest statistically complete sample of VLBI-monitored radio-loud core-dominated AGN. The jets of the 133 radio-brightest blazars and active galaxies of the northern sky are being monitored for more than a decade now with the VLBA at milliarcsecond resolution. Archival X-ray spectroscopic data above 2 keV is available for 50 of them. I will compare those to other classes of AGN, in particular radio-quiet ones, and will discuss correlations between the X-ray spectra and parsec-scale relativistic beaming and jet parameters such as superluminal jet speeds, jet Doppler factors, and luminosities.	P160
Sarah Kaufmann	Argelander-Institute for Astronomy at the University of Bonn	The X-ray properties of radio-loud core-dominated AGN at different redshifts	We study a sample of 36 flat-spectrum radio-loud AGN, observed with the X-ray observatories ASCA, BeppoSax, Chandra and XMM-Newton. The sample covers a broad redshift range up to z=4.5 which provides the opportunity to search for evolutionary effects. We found that the basic shape of the X-ray spectra observed in the energy range 2-10 keV is the same for the full range of different redshifts. About 30% of the objects show a significant amount of excess absorption which is unexpected for highly beamed blazar sources. The excess absorption measured in the quasars seems to increase with redshift.	P150
Almus Kenter	SAO	Large scale structure in the Xbootes survey	We present results from the XBootes survey. This survey consists of 126 separate Chandra ACIS-~I observations each of approximately 5000 seconds in duration. The observations comprise a field of view of ~ 9 degree^2 and are part of the multi-wavelength NOAO Deep Wide Field Survey (NDWFS). 3293 x-ray sources have been detected with flux ≥ 8x 10^-15 (0.5-7 keV). These X-ray data are combined with optical observations and the combined data set is observed with the multi-fiber spectrograph (HECTOSPEC) as part of the AGN and Galaxy Evolution Survey (AGES). We present results on large scale structure, redshift distribution, and the three dimensional 2-point correlation.	O6
Roy Kilgard	Harvard-Smithsonian Center for Astrophysics	Normal Galaxies in the Chandra/SWIRE X-ray Survey	We present results on the normal galaxy population detected in the Chandra/SWIRE X-ray survey, the largest (0.6 sq. deg), deepest (broad bandf lux limit = 7e-16 erg/cm^2/s) contiguous region observed by Chandra to date. We find 49 X-ray sources that are spatially coincident with optically extended galaxies, 6% of the total X-ray sources. We discuss the multiwavelength properties of these galaxies, including classification of the host galaxies based on their spectral energy distribution. We also discuss the contribution of the sources to the total X-ray population of this field and compare our results with those from the ChaMP survey (Kim et al, 2006).	P260
Minsun Kim	SAO	Chandra Multiwavelength Project X-ray Point Source Number Counts and the Cosmic X-ray Background	We present the Chandra Multiwavelength Project (ChaMP) X-ray point source number counts and the cosmic X-ray background (CXRB) flux densities in multiple energy bands. To quantitatively characterize the sensitivity and completeness of the ChaMP sample, we perform extensive simulations. We also include the ChaMP+CDFs (Chandra Deep Fields) number counts to cover large flux ranges from 2x10^-17 to 2.4x10^-12 (0.5-2 keV) and from 2x10^-16 to 7.1x10^-12 (2-8 keV) erg cm-2 sec-1. We detect breaks in the differential number counts and they appear at different fluxes in different energy bands. Assuming a single power law model for a source spectrum, we find that the same population(s) of soft X-ray sources causes the break in the differential number counts for all energy bands. We measure the resolved CXRB flux densities from the ChaMP and the ChaMP+CDFs number counts with and without bright target sources. Adding the known unre! solved CXRB to the ChaMP+CDF resolved CXRB, we also estimate total CXRB flux densities. The fractions of the resolved CXRB without target sources are 78 +/- 1/1 % and 81 +/- 2/2 % in the 0.5-2 keV and 2-8 keV bands, respectively. These fractions increase by ~1% when target sources are included.	P60
Anton Koekemoer	Space Telescope Science Institute	Probing AGN Populations beyond Redshifts 6 - 7 using Large X-ray Surveys	The advent of deep and wide multi-wavelength surveys provides unprecedented new opportunities to search for very high redshift active galactic nuclei by constructing samples of sources that are detected at X-ray wavelengths but completely undetected at optical wavelengths to very deep limits. I will describe recent work on constructing samples of candidate AGN at or beyond redshift 6 - 7, such as the `EXO's selected from deep multiband X-ray/HST/IR surveys such as GOODS, COSMOS and similar projects. The optical flux limits are combined with IR detections, together with X-ray fluxes, to model the spectral energy distributions of the sources and help discriminate intermediate-redshift interlopers from the rare number of likely high-redshift sources. The resulting constraints on the number of candidate AGN at or above redshift 7 are used to examine the evolution of the AGN luminosity function at high redshift, with corresponding implications for the co-evolution of ga! laxies and their central black holes.	O1
Mirko Krumpe	Astrophysical Institute of Potsdam, Germany	The XMM-Newton Survey in the Marano Field	We report on a medium deep XMM-Newton survey of the Marano field and optical follow-up observations. With a total of 110 identifications in our core sample we reach a completeness of ~65%. A fraction of 30% of the XMM-Newton sources are identified as type II AGN with redshifts mostly below 1.0. We estimate absorbing column densities and show that the ratio of absorbed to unabsorbed objects is significantly higher for type II AGN than for type I AGN. However, we find a few unabsorbed type II AGN and significant number of heavily absorbed type I AGN, mostly at high redshifts.	P110
Mark Lacy	Spitzer Science Center, Caltech	X-ray properties of Spitzer-selected type-2 quasars	Spitzer surveys are now finding many examples of obscured quasars. However, X-ray follow-up of these objects has been minimal, principally because a significant amount of exposure time (10-100ks) is needed to detect these objects, even those with relatively bright mid-infrared fluxes of several mJy at 24mu. Nevertheless, the presence of such a population has important implications for models of the hard X-ray background. I will present results for a subsample of 20 mid-infrared selected AGN in the SWIRE/XMM field, which demonstrate that a large fraction of obscured quasars have high X-ray absorption columns, and are likely to be Compton thick.	O10
Fabio La Franca	Universita` Roma tre	The Hard X-Ray Luminosity Function of AGNs	We have determined the cosmological evolution of the density of AGNs and of their NH distribution as a function of the unabsorbed 2-10 keV luminosity up to redshift 4. We used the HELLAS2XMM sample combined with other published catalogs, yielding a total of 508 AGNs. Our best fit is obtained with a luminosity-dependent density evolution (LDDE). There is evidence that the fraction of absorbed (NH〉10^22 cm-2) AGNs decreases with the intrinsic X-ray luminosity and increases with the redshift.	P80
Hermine Landt	Harvard-Smithsonian Center for Astrophysics	The Deep X-ray Radio Blazar Survey (DXRBS) - Radio and X-ray Number Counts, Evolution and Luminosity Function	We present the faintest blazar sample currently available, based on the Deep X-ray Radio Blazar Survey (DXRBS), which includes 129 flat-spectrum radio quasars and 24 BL Lacs down to radio fluxes and powers more than ~10 times fainter than published blazar samples. Our results constrain blazar evolution, unified schemes, and the so-called "blazar sequence".	P170
Bret Lehmer	Penn State University	The Properties and Redshift Evolution of Intermediate-Luminosity Off-Nuclear X-Ray Sources in the Chandra Deep Fields	We present a sample of 24 intermediate-redshift (z ~ 0.05-0.3) off-nuclear X-ray sources that are coincident with optically bright (V_606 < 21) field galaxies within the Chandra deep fields. These off-nuclear sources have X-ray properties and optical environments similar to intermediate-luminosity X-ray objects (IXOs) in the local universe. We find that the fraction of intermediate-redshift galaxies hosting an off nuclear source with luminosity L_X > 10^39 erg s-1 is suggestively elevated over the local IXO fraction by a factor of ~ 1.9 +/- 1.4/1/3 A rise in this fraction may be a consequence of the observed increase in star-formation activity with redshift.	P270
Bret Lehmer	Penn State University	The X-ray Properties of Early-Type Galaxies in the Extended Chandra Deep Field-South	We present X-ray stacking results from a large sample of z < 0.7 early-type galaxies within the Extended Chandra Deep Field-South region. We study separately optically luminous and faint galaxy samples, which have soft X-ray emission dominated by hot interstellar gas and low mass X-ray binaries (LMXBs), respectively. We observe no significant evolution in the X-ray emission from our optically luminous samples, which we attribute to intermittent heating of the hot interstellar gas (possibly from AGNs). For our optically faint samples we find suggestive evidence for evolution, possibly due to changes in LMXB populations.	O4
Karen Lewis	NASA GSFC	Follow-up of the XMM Slew Survey: 5070 square degrees and counting	The XMM Slew Survey covers 5070 square degrees and is an order of magnitude more sensitive in the 2-12 keV band than previous all-sky surveys, opening up the possibility of studying large numbers of intermediate redshift AGNs. We have begun a follow-up campaign for ~300 sources with 2-12 keV detections. Although most have optical/IR counterparts, only 1/3 have been robustly classifed (including 65 AGNs). Most are classified simply as "Galaxy". SDSS/6dF spectra of some reveal an AGN, while others appear "dull". Our initial efforts focus on these poorly studied galaxies and includes improved X-ray observations, optical spectroscopy and IR/optical imaging.	P220
Andisheh Mahdavi	University of Victoria	JACO: Simultaneous X-ray, Sunyaev-Zeldovich, and Weak Lensing Modeling of Relaxed Clusters	I will discuss a method for the Joint Analysis of Cluster Observations. By combining measurements of the X-ray spectrum, gravitational lensing shear, and Sunyaev-Zel'dovich decrement for the same cluster, JACO yields powerful constraints on the distribution of baryonic and non-baryonic matter in a relaxed system. Chandra, XMM-Newton, Cosmic Background Imager, and CFHT observations of the well-studied cluster Abell 478 yield a dark matter distribution that is shallower than standard CDM models. I will preview the application of JACO to the Canadian Cluster Comparison Project, a survey of massive, intermediate-redshift systems.	P350
Vincenzo Mainieri	Max Planck Institute - European Southern Observatory	NH distribution from deep and large area X-ray surveys.	We present a detailed analysis of the X-ray spectra of point like sources in the XMM-COSMOS field. Our sample includes 134 X-ray sources with more than 100 net counts in the [0.3-10] keV energy band and that have been spectroscopically identified. The majority (72%) of the sources are well described by a simple power-law model, ~23% of them show intrinsic absorption. The remaining ~5% of the sources require a more complex modeling with additional components to the simple power-law. The average photon spectral slope of our sources is Gamma=2.06 +/- 0.08, with an intrinsic dispersion of ~0.24. The distribution of intrinsic absorbing column densities is different among broad line AGN and not broad line AGN. We will complement this sample with the results of our X-ray spectral analysis in the CDF-S area (~0.1 deg2). 99% of these sample has either a spectroscopic or a good photometric redshift. We demonstrated that at least part of a still mi! ssing population of Compton thick sources can be accounted for in deep X-ray surveys when all the X-ray sources are included (thanks to the use of accurate photometric redshifts for the still unidentified ones). In particular 14 sources have a pure reflection X-ray spectrum, typical of Compton-thick sources (N_H > 1.5 x 10^24 cm-2), which we can convert in a surface density as high as (200 +/- 50) deg-2. We will finally present our current best estimate of the intrinsic N_H distribution of AGN coming from these two surveys, discussing in details the corrections for incompleteness we had applied.	O2
Paul Martini	Ohio State University	AGN in Clusters of Galaxies	AGN in clusters of galaxies are commonly invoked to explain the absence of cold gas in cluster cores, although they appear to be substantially rarer in rich environments than in the field. I will present results from a Chandra study of eight low-redshift clusters that has systematically measured the AGN fraction in clusters and describe their spatial, kinematic, and host galaxy distributions. I will also briefly discuss their implications for AGN fueling, galaxy evolution, and heating the ICM.	O6
Silvia Mateos	University of Leicester	Statistical analysis of the X-ray emission properties of type-1 AGN in the XMM-2dF Wide Angle Survey	I will present the results of a statistical analysis of the X-ray emission properties of one of the largest samples of X-ray selected type-1 AGN assembled so far (>600 objects) from the XMM-2dF Wide Angle Survey. This study allows us to constrain the broad band continuum and intrinsic X-ray absorption properties of type-1 AGN and investigate their dependence with X-ray luminosity and redshift. I will also show how AGN population studies will benefit from the study of samples of objects selected from the 2XMM catalogue with both Sloan and UKIDSS data available	O8
Takamitsu Miyaji	Carnegie Mellon University	AGN Clustering and Environments in X-ray Surveys	Clustering properties and environments of active galactic nuclei provide yet another key to understanding the formation/triggering mechanism of AGN activities. I review the current status of AGN clustering and environment studies from X-ray surveys and discuss their implications for AGN formation/evolution and cosmology. Topics include comparisons amonng AGN correlation functions from various X-ray and opticl surveys, statistical challenges in the correlation function analysis, and the evolution of AGN clustering/bias with redshift. I further overview the implications of the AGN clusterings in terms of dark-matter halo occupation, typical lifetime of AGN activities, and cosmolgy. Future prospects are discussed.	O6
Kirpal Nandra	Imperial College London	Survey Challenges	Chandra and XMM surveys have now resolved most of the X-ray background below 10 keV. While many of the important matters arising are starting to be addressed, almost all the important issues remain controversial or have large uncertainties. These include, but are not limited to a) how AGN activity evolves, and the accretion history; b) the fraction of absorbed objects and any dependence of absorption on, e.g. luminosity or redshift; c) the triggering mechanism for AGN activity; d) its relationship to star formation and galaxy evolution. Reaching robust conclusions requires careful data reduction and analysis, and proper consideration of biases and completeness. These issues and their implications will be discussed.	O12
Dara Norman	NOAO	Weak lensing selected, X-ray confirmed galaxy clusters & the AGN closest to them	The Deep Lens Survey (DLS) team has identified a unique sample of galaxy clusters through weak gravitational lensing shear mapping (Wittman et al. 2006). Chandra X-ray confirmation of several of these clusters has serendipitously uncovered large numbers of X-ray point sources, presumably AGN, in the fields of these clusters. We have begun a survey to characterize these AGN; determine their redshifts, luminosities and distributions relative to the mass and hot gas of the cluster environment. This study will also allow us to test the validity of assumptions made about the formation and evolution of AGN in hierarchical structure formation models.	O7
Richard Owen	University of Leicester	X-ray Emission from Nearby 'Normal' Spiral Galaxies	We present preliminary results from a survey of nearby late-type spiral galaxies observed by XMM-Newton. We have developed new procedures to study the point source distribution and unresolved emission present. The X-ray luminosity function of the point sources is used to estimate the proportion of unresolved emission which is truly diffuse, and the origins of this diffuse emission are explored by comparison of its morphology to that in other wavebands. Using a sample of 30-40 galaxies, we aim to extract a consistent set of derived X-ray parameters appropriate to late-type spiral galaxies such as our own.	P280
Shinae Park	Harvard-Smithsonian	A Spitzer-Chandra Survey of AGN in the Extended Groth Strip	The All Wavelength Extended Groth Strip International Survey (AEGIS) is a widespread collaborative effort to study sources in the EGS, a 2 degree by 10 arcmin sky field with low column density and high galactic and ecliptic latitude. Here we take advantage of deep Chandra and Spitzer observations of the field to present the infrared properties of X-ray detected sources, including their color-color identification, SED shape, and source variability. We use these properties in order to better understand multi-wavelength AGN identification	P130
Mari Polletta	University of California, San Diego	Spectral Energy Distributions of Hard X-ray selected AGN in the XMDS Survey	The spectral energy distributions (SEDs) of AGNs and their dependence on luminosity and absorption are characterized in order to evaluate the selection biases of multi-wavelength surveys, understand the nature of elusive AGNs, investigate the origin of AGN red mid-IR colors, and test model predictions for AGNs at high-z and luminosities. This study is based on a hard (2-10 keV) X-ray selected sample from the XMM-Medium Depth Survey (XMDS). The multi-wavelength data set includes optical data from the VVDS, CFHTL surveys, infrared data from the SWIRE survey, and X-ray data from the XMM-LSS survey.	P30
Mari Polletta	University of California, San Diego	X-ray surveys in the SWIRE fields	The combined capabilities of Spitzer, Chandra, and XMM-Newton provide a unique opportunity to investigate the properties of AGNs over large cosmic volumes. We present an overview of the X-ray surveys carried out in the SWIRE fields and report results from the Chandra/SWIRE survey in the Lockman Hole and the XMM-Newton Medium Deep Survey in the XMM-LSS field. The multi-wavelength SEDs of AGNs as a function of selection method, luminosity, and obscuration are characterized to asses AGN samples selection biases. The nature of obscured AGNs and their contribution to the cosmic X-ray background are discussed.	O10
Trevor Ponman	Birmingham	Cluster structure and feedback	It has been known for many years, from the slope of the X-ray luminosity-temperature relation, that the baryonic contents of groups and clusters of galaxies are not self-similar, despite the fact that cosmological simulations lead us to expect a high degree of similarity in their dark matter content. The origin of this difference in behaviour between dark matter and baryons lies in the extra physics - especially heating and cooling processes - to which baryons are subject. Hence the study of the structure of the hot gas in galaxy systems as a function of cluster mass and of redshift, can provide important clues to the physical processes which we understand so poorly, and also acts as a probe of galaxy evolution. In this talk, I will review the results from studies of cluster structure and scaling which bear on the thermal and chemical history of the intergalactic medium.	O7
Gordon Richards	Drexel University	Bayesian Quasar Classification on the SDSS Equatorial Stripe	We discuss the application of Bayesian techniques to classify quasars, identifing of order 1 million quasars in the Sloan Digital Sky Survey. Photometric redshifts can be computed to better than 0.1 in redshift for the majority of the sample. Deeper coverage in the southern equatorial region allows for quasar selection to nearly i=22 and provides an optimal area for the next generation of deep-wide mid-IR and X-ray surveys. Science applications include using the quasar luminosity function to constrain merger models and determining absolute cosmic distances to high-redshift using baryon accoustic oscillations.	P250
Emmanouel Rovilos	IAA-NOA	Radio observations of the Chandra Deep Field South Are radio sources more obscured?	We have cross-correlated data from the Australia Telescope Compact Array (ATCA) with X-ray observations of the southern Chandra Deep Fields, reaching flux depths of 60 Jy-6 and 1.3x 10^-16 ergs cm-2 s-1 respectively. Our aim is to check for the existence of correlation between radio emission and obscuration of AGN. Previous works have shown that radio counterparts are preferentially detected toward obscured AGN, which possibly suggests that both radio emission and X-ray absorption are linked with circumnuclear star formation. Searching for radio counterparts among all X-ray detected sources in the two Chandra fields we get detection rates of 14% and 9% for the CDF-S and the ECDF-S respectively. After the extraction of ``normal'' galaxies and sources not detected in the hard X-ray band (2-8 keV), we found no strong evidence of correlation between the existence of a radio counterpart and X-ray obscuration. For a sizable fr! action of the sources the radio emission is linked star formation, suggested by the Spitzer mid-infrared (24 microns) and radio correlation. Limiting our sample to those sources selected by their infrared detection again reveals no correlation between X-ray obscuration and radio detection. However, we detect a correlation if we only consider sources having some degree of obscuration. We interpret this result by linking X-ray obscuration with star-forming activity which is anisotropically distributed round the AGN.	P120
Kivanc Sabirli	Carnegie Mellon University	The XMM Cluster Survey	The XCS is a serendipitous X-ray galaxy cluster survey being conducted using archival data taken by ESA's XMM-Newton satellite. Galaxy clusters trace the large scale structure of the universe, and their number density evolution with redshift provides one way to measure cosmological parameters, independent of cosmic microwave background experiments or supernovae cosmology projects. The current status of the survey and the associated NOAO optical imaging survey will be presented.	P330
Cristian Saez	Pennsylvania State University.	A Study of AGN evolution in the X-ray band.	We present results from a statistical analysis of bright radio-quiet AGNs selected from the Chandra deep field surveys in the redshift range of 0.5<z<4. Taking a sub-sample of 33 radio-quiet AGNs in the redshift range 1.6<z<3.3 we found that the X-ray power-law photon index (Gamma) of radio-quiet AGNs is correlated with their 2-10 keV rest-frame X-ray luminosity (Lx) at the greater than 99.9% confidence. Combining our results with those from previous studies we find that the Gamma - Lx correlation has a null hypothesis probability of 5x10^(-7). We investigate this correlation in the context of steady corona models.	P70
Norbert Schartel	XMM-Newton SOC, ESA	A new observing mode for XMM-Newton	When XMM-Newton moves from one target to another its cameras continue to observe. These observations, performed when XMM-Newton was slewing, allowed the compilation of a catalogue: the XMM-Newton Slew Survey. Reflecting these positive experiences, the XMM-Newton SOC started the development of a new observing mode, which basically is a slow slew- observing mode. The talk gives an overview of the slew survey, outlines the status of the development of the new observing mode and iterates the scientific potential especially with respect to large area surveys.	P210
Nicholas Seymour	Spitzer Science Center	Revealing the Nature of the Sub-mJy Radio Population with deep Multi-wavelength (X-ray/Optical/IR) Observations	Probing the exact nature of the faint (sub-mJy) radio population has been historically difficult due to the low luminosity of these sources. Using deep observations from Chandra/XMM-Newton/Spitzer and the GMRT we are able to disentangle the AGN and star-forming populations for the first time, using X-ray spectra/hardness ratios, IR colours and radio spectral indices. We are able to examine the star-formation history of the universe up to z~2 in a unique way based on an unbiased star-formation rate indicator, radio luminosity. This work provides an alternative perspective on the distribution of star-formation by mass, ``downsizing''.	O8
John Silverman	Max-Planck-Institut fur Extraterrestrische Physik	The evolution of supermassive black holes out to z ~ 5	We present a measure of the hard (2-8 keV) X-ray luminosity function of active galaxies to trace the growth of supermassive black holes out to early epochs. To do so, we have compiled a large AGN sample from published catalogs and the Chandra Multiwavelength Project (ChaMP) that significantly improves the statistics at z > 3. We discuss new analytic model fits that cover the full redshift range and enables us to determine the mass and accretion rate distributions at high redshift. We further address the improvements possible with current (e.g. E-CDF-S) and future (cCOSMOS) surveys with Chandra to improve the luminosity function at z > 4 and the low luminosity end at z > 1.5.	O1
Rebecca Smith	University of Leicester	Developing a photometric redshift code for use with large X-ray selected AGN samples	The release of large X-ray catalogues enable large samples of X-ray selected AGN to be investigated. To determine evolutionary properties of such a sample, the redshift of each object must be known. Spectroscopically determined redshifts, although accurate, are time consuming to collect. Photometric redshift estimates are more suitable for large surveys. Using samples of known AGN from several fields we cross-correlate to find optical and infra-red counterparts. Using a photometric redshift code written specifically for use with SDSS colours, we develop a method of obtaining accurate photometric redshifts based on known properties of the sources.	P240
Aaron Steffen	Penn State	Extending alpha_OX studies to include the numerous low-to-moderate luminosity AGNs	We examine the luminosity dependence and evolution of the X-ray-to-UV flux ratio (alpha_OX) for a sample of optically selected, radio-quiet, non-BAL AGNs. Combining luminous SDSS AGNs (including the 32 most luminous SDSS AGNs) having pointed and serendipitous Chandra, XMM-Newton, and ROSAT observations together with low-to-moderate luminosity AGNs in the Extended Chandra Deep Field - South maximizes coverage of the luminosity-redshift plane and includes the AGNs that dominate numerically in the Universe. Our large, homogeneous sample provides quantatively better constraints on the alpha_OX, L_UV, and z relation than earlier studies. Our data also suggest a non-linear relationship between alpha_OX and log (L_UV).	O1
Gordon Stewart	Dept. of Physics and Astronomy, Leicester University	Cosmic Variance From the 2XMM Catalogue G C Stewart, M G Watson, S Mateos, R Smith	Number counts from 2XMM serendipitous catalogue number counts are used to probe the cosmic variance at a range of depths and scales.The high sensitivity, wide-field and large sky coverage of this catalogue are ideal for this analysis. The results are used in combination with results from the deep surveys of Chandra and XMM to constrain the fluctuation amplitudes at a typical redshift of 1-2. Comparison with results obtained using other techniques can be used to investigate the bias parameter and how well for various source populations`light' traces the matter fluctuations.	P200
Jonathan Tedds	University of Leicester	X-ray Variability in the 2XMM Pre-release Serendipitous Catalogue	We present an X-ray variability study using the 2XMMp XMM-Newton Pre-release serendipitous source catalogue to provide constraints on short time-scale (mins-hours) variability for ~10% of the point source catalogue, i.e. ~10,000 extragalactic X-ray sources - a uniquely large sample for such studies. Furthermore since up to ~30% of catalogued sources have been observed more than once we can extract further information on long-term variability on scales of months-years for thousands of objects. Time series and spectral products were automatically generated for all sources having total EPIC > 500 counts in the energy range 0.2-12 keV. To test for variability we used a Chi-squared test (suitable for binned data) with the Pearson's approximation for Poissonian data and excluded high background flaring times. We determine the short-term variability properties for a large AGN sample, selected via Fx/Fopt following cross correlation with e.g. SDSS DR5. We also highlight extreme longer term variables that might be candidate Komossa-type objects in which an AGN is swallowing stars.	O5
Paolo Tozzi	INAF - Osservatorio Astronomico di Trieste	Spectral analysis of X-ray sources in the CDFS	Deep X-ray surveys are providing crucial information on the evolution of AGN and galaxies. We review some of the latest results based on the X-ray spectral analysis of the sources detected in the Chandra Deep Field South, namely: i) constraints on obscured accretion; ii) constraints on the missing fraction of the X-ray background; iii) the redshift distribution of Compton-thick sources and TypeII QSO; iv) the detection of star formation activity in high-z galaxies through stacking techniques; v) the detection of large scale structure in the AGN distribution and its effect on nuclear activity. Such observational findings are consistent with a scenario where nuclear activity and star formation processes develop together in an anti-hierarchical fashion.	O1
Laura Trouille	University of Wisconsin-Madison	Optical Properties of the LHN-2 and CLASXS Chandra X-ray Survey Sources	In this poster, we present the spectroscopic and photometric observations of the X-ray sources detected in a wide-area, moderately deep Chandra X-ray survey of a second field near the Lockman Hole. We combine our results with the previous Steffen et al. 2004 findings for the CLASXS field. We separate the X-ray sources by optical spectral type and examine the colors, apparent and absolute magnitudes, and redshift distributions for the broad-line and non-broad-line active galactic nuclei. We also compare the group structures in the CDFN with those in this Lockman Hole field as well as the CLASXS field in order to investigate if the environments of the X-ray sources evolve with redshift.	P230
Jack Tueller	NASA/GSFC	Swift/BAT Hard X-ray Survey of AGN	The BAT hard X-ray (14-100 keV) survey is the first complete and uniform survey of the whole sky not effected by absorption. The survey has detected >200 AGN with a low median z=0.03. Many of these are highly absorbed and have not been previously identified as AGN. The complete logN/LogS and luminosity function for local AGN will be presented. The survey also yields the spectral distributions and average spectrum for local AGN. Using Swift/XRT, we have 0.2-10 keV spectra for all the BAT AGN. The Swift spectral results are not consistent with the X-ray background without invoking strong evolution.	O2
Panayiotis Tzanavaris	National Observatory of Athens	The luminosity function and evolution of normal galaxies	We present initial results on the luminosity function and evolution of normal galaxies. We are using Chandra data from the deep fields CDFS-S and CDF-S as well as shallower data from the ECDFS and the XBOOTES. We are selecting normal galaxies using the following criteria: a) Lx < 10^42 b) log(fx/fo) < -1 c) hardness ratio < 0. We present our results separately for early type and late type systems. Finally, we compare our results with previous Chandra findings as well as with the XMM luminosity function in the local Universe.	O4
Cristian Vignali	Dipartimento di Astronomia, Universita` di Bologna	The obscured X-ray source population in the HELLAS2XMM survey: the Spitzer perspective	We present Spitzer IRAC and MIPS observations of a sample of eight high-luminosity, obscured AGN at z>1 selected in the 2-10 keV band from the 1.4 square degree HELLAS2XMM survey and characterized by extreme R-K colors (typically >5). The nuclear infrared spectral energy distributions of these AGN are computed using the K-band and Spitzer data, while the masses of the black holes are estimated using the local L(K)-M(BH) relation. By combining all the available information, the bolometric luminosity and Eddington ratio of these obscured AGN are derived and compared to literature results.	O10
Alexey Vikhlinin	SAO	High-redshift galaxy cluster surveys	This talk will focus on the present status of high-redshift cluster surveys. The available data already provides interesting cosmological constraints, highly complementary to those from CMB and SN Ia. I will also discuss the prospects for future work with Chandra and XMM, as well as with the proposed quasi all-sky X-ray surveys and experiments using other techniques.	O7
Sheng Wang	Columbia University	Constraining Dark Energy with X-ray Selected Galaxy Clusters	Future surveys will yield thousands of galaxy clusters and can place precise statistical constraints on cosmological parameters. We use a Fisher matrix approach to quantify constraints in forthcoming surveys that will identify clusters by their X-ray emission. Non-cosmological parameters are simultaneously included in our analysis (self-calibration), which express uncertainties in the mass-observable relations. We find that by combining observables, such as the abundance evolution (dN/dz) and the spatial power spectrum (P(k)), degeneracies (both among cosmological parameters, and between cosmological and non-cosmological parameters) can be broken, and tight constraints can be obtained on (1) the evolution of the dark energy equation of state dw/dz and on (2) the mass of neutrinos. Combining cluster data with CMB anisotropy measurements by Planck further breaks degeneracies and tightens contstriants.	P360
Mike Watson	Uiniversity of Leicester	The 2XMM Catalogue And Early Science	The XMM-Newton Survey Science Centre has recently released the second XMM-Newton serendipitous source catalogue, 2XMMp. This is the largest X-ray source catalogue ever made, including more than ~ 150000 objects. The catalogue itself is also complemented by X-ray spectra and light curves for the brighter objects in each field (around 10% of the total). 2XMM covers an area large enough (~ 300 sq.deg.) to provide large object samples and to reveal the rarest and most extreme objects in the X-ray sky. In this paper we will describe the 2XMM catalogue and highlight some early science results (and future potential) obtained by cross-matching with SDSS DR5 and the UKIDSS surveys.	P190
Lisa Winter	University of Maryland	Early Results from SWIFT's BAT AGN Survey	The SWIFT gamma ray observatory's Burst Alert Telescope (BAT) has detected a sample of active galactic nuclei (AGN) based solely on their hard X-ray flux (15-150 keV) (Markwardt et al. 2005). With approximately 200 BAT AGN sources, and an expected sample of 400 within the next two years, the potential scientific gain from a multi-wavelength study of the first such unbiased (unaffected by absorption or dilution from starlight), flux limited AGN sample is great. We present for the first time XMM follow-ups of 22 BAT AGN sources. We present X-ray spectra and light curves as well as UV data for these objects.	O5
Edward Wright	UCLA	Surveying for AGNs with the Widefield Infrared Survey Explorer (WISE)	Active Galactic Nuclei are bright and relatively unobscured in both the infrared and the hard X-ray bands. The Widefield Infrared Survey Explorer (WISE) will survey the entire sky in 4 mid-IR bands from 3.3 to 23 microns. The 23 micron band, with a required sensitivity of 2.6 mJy, should be able to detect a half million AGNs with a median redshift of 1.2 if the Hopkins et al. (2006) wavelength dependent quasar luminosity function is correct.	P290
Yueheng Xu	XROA, University of Leicester	"Normal" galaxies sample from 2dF-XMM Wide Angle Survey	We present a sample of 72 "normal" galaxies selected from 2dF-XMM Wide Angle Survey and identify the origin of the X-ray emission from these galaxies. These "normal" galaxies are selected as having either absorption or narrow emission line spectra, X-ray-to-optical flux ratios log(f_X/f_R) ≤ -1 and 0.2-12 keV luminosity L_X ≤ 10^43 erg s-1. We discuss the relative fractions of this sample "normal" galaxies which are ellipticals/groups, low-luminosity AGNs and starbursts.	O4

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