The talks are in the same order as the Program Schedule.
Uchiyama, Yasunobu - Resolved jets in quasars and radio galaxies
Perlman, Eric - Insights on Jet Physics & High Energy Emission Processes from Optical Polarimetry
Chartas, George - Imaging AGN using gravitational microlensing
Yasunobu Uchiyama (ISAS/JAXA)
Relativistic jets at hundreds of kiloparsecs from the quasar nucleus generally exhibit strong X-ray emission in excess of that anticipated by a synchrotron-self-Compton model, as revealed by surveys with Chandra. Despite extensive work, the dominant X-ray emission process in quasar jets remains unsettled. Solving this problem will revolutionize our ideas regarding relativistic jets and outflows in the Universe. In this talk, we present results from Spitzer infrared observations of X-ray jets in quasars and radio galaxies, combined with multifrequency imaging data from VLA, Hubble, and Chandra. A particular emphasis is placed on our multifrequency analysis of the kiloparsec-scale jet in the well-known quasar 3C 273, which offers new insights into the controversial origin of the X-ray emission seen in the relativistic jets of quasars and radio galaxies. Our analysis suggests that a population of particles distinct from radio-emitting electrons produces the resolved X-rays in powerful jets through a synchrotron process. We discuss implications for particle acceleration processes operating in relativistic jets. Finally we address effective investigations to be done with current instruments as well as future prospects of this area.
Eric Perlman (Florida Institute of Technology) , C. A. Padgett, M. Georganopoulos (JCA/UMBC), F. Dulwich, D. M. Worrall, M. Birkinshaw (U. Bristol), W. B. Sparks, J. A. Biretta (STScI), C. P. O'Dea, S. Baum (RIT), A. S. Wilson
Because of their direct tie with the magnetic field in the emitting region, polarimetry can be a powerful tool in disentangling the physics of extragalactic jets. Polarimetry in multiple emission bands can prove particularly helpful, as they can help disentangle cases where emission in multiple bands might originate in physically different regions. A total of nine jets have now been observed polarimetrically with HST, with the results on all but two having been published during the last 18 months. I will discuss the relationship between optical and radio polarization for extragalactic jets, its implications for jet energetic and magnetic field structure, and its importance for understanding the X-ray emission properties seen by Chandra. We are finding that there is not a general pattern in these properties, with each source having somewhat different polarization properties and relationship to X-ray emission. This strongly reinforces the idea that the jets of radio galaxies are not homogeneous flows.
George Chartas (Penn State) , C. S. Kochanek(OSU), X. Dai(OSU), N. Morgan(OSU), G. Garmire(PSU)
Resolving the emission regions of distant quasars is beyond the current capabilities of present-day telescopes. Until the spacial resolution of telescopes improves to reach the level of tens of nano-arcseconds we will have to rely on indirect methods of mapping the emission regions of quasars. One promising method of imaging AGN accretion disks involves microlensing of the continuum and line emission regions that can occur in lensed AGN. We have initiated a multiwavelength monitoring campaign of several microlensing candidates with the main scientific goal of measuring the structure of AGN in the optical and X-ray bands in order to test disk models. We present constraints on the sizes of AGN accretion disks and their hot coronae. These constraints were obtained by monitoring microlensing events in quasars Q1131-1231 and HE1104-1805. X-ray monitoring observations of these quasars were performed with the Chandra X-ray Observatory and B, R and I band observations were made with the Smarts Consortium 1.2m telescope in Chile. Stacking of the Chandra observations has also provided constraints of the properties of two clusters of galaxies in the vicinity of Q1131-1231.
Guido Risaliti (SAO)
I present the results of a Chandra monitoring of the Seyfert Galaxy NGC 1365, which revealed an occultation event with a duration of less than two days, implying a distance of the circumnuclear absorber of less than 0.01 pc, and a size of the X-ray emitting region of 10^14 cm. I will discuss the implication of this result in the context of the unified model, and will present the first results of a long ( 5 days) XMM monitoring of this source.
Daniel Evans (Harvard University) , Julia Lee (Harvard University), Jane Turner (UMBC/GSFC), Kim Weaver (GSFC), Herman Marshall (MIT)
We present Chandra ACIS-S (50 ks), HETGS (250 ks) and XMM-Newton RGS (60 ks) imaging and spectroscopic observations of NGC 2110, a source classified as a Narrow Emission Line Galaxy, the subclass of Seyferts historically noted for their particularly flat X-ray spectra. Although the nuclear X-ray spectrum of NGC 2110 can be modeled as a power law of photon index absorbed by a column of
3 x 1022 cm-2, the excess absorption we detect at the Si K and Fe K edges implies the need for a more complex spectral model, which we find in the form of a "canonical" 
AGN spectrum modified by patchy absorption from multiple layers of neutral material. The measured photon index and high intrinsic absorption of the nuclear spectrum of NGC 2110 are consistent with that of a typical Seyfert 2 galaxy, which demonstrates that NELG are typical AGN viewed through slightly more complex absorption, rather than a separate subclass of objects on their own. Based on additional multiwavelength imaging studies, we also find resolved soft X-ray emission 160 pc north of the nucleus, which is spatially coincident with [OIII] emission (HST), but lies just beyond the northern edge of the small-scale radio jet in the source. Taken with the evidence for ionized emission in the HETGS spectra of NGC 2110, we suggest that both photoionization and collisional ionization processes play a role in the circumnuclear environment of the source.