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Models for the Type Ic Hypernova SN 2003lw associated with GRB 031203
Della Valle, Massimo; Tominaga, Nozomu; Nomoto, Ken'ichi +10 more
The gamma-ray burst GRB 031203 at a redshift z=0.1055 revealed a highly reddened Type Ic supernova, SN 2003lw, in its afterglow light. This is the third well-established case of a link between a long-duration GRB and a Type Ic SN. The SN light curve is obtained by subtracting the galaxy contribution and is modeled together with two spectra at near…
A Multiwavelength Study of Sgr A*: The Role of Near-IR Flares in Production of X-Ray, Soft γ-Ray, and Submillimeter Emission
Dowell, C. D.; Bélanger, G.; Goldwurm, A. +8 more
Although Sgr A* is known to be variable in radio, millimeter, near-IR, and X-rays, the correlation of the variability across its spectrum has not been fully studied. Here we describe highlights of the results of two observing campaigns in 2004 to investigate the correlation of flare activity in different wavelength regimes, using a total of nine g…
Probing the Coevolution of Supermassive Black Holes and Quasar Host Galaxies
Ho, Luis C.; Rix, Hans-Walter; Peng, Chien Y. +2 more
At low redshift, there are fundamental correlations between the mass of supermassive black holes (MBH) and the mass (Mbulge) and luminosity of the host galaxy bulge. We investigate the same relation at z>~1. Using virial mass estimates for 11 quasars at z>~2 to measure their black hole mass, we find that black holes at …
Nonthermal High-Energy Emission from Colliding Winds of Massive Stars
Reimer, A.; Reimer, O.; Pohl, M.
Colliding winds of massive star binary systems are considered as potential sites of nonthermal high-energy photon production. Motivated by the detection of synchrotron radio emission from the colliding wind location, we here investigate the properties of high-energy photon production in colliding winds of long-period WR+OB systems. Analytical form…
The Spiderweb Galaxy: A Forming Massive Cluster Galaxy at z ~ 2
Pentericci, Laura; Franx, Marijn; Illingworth, Garth D. +11 more
We present a deep image of the radio galaxy MRC 1138-262 taken with the Hubble Space Telescope (HST) at a redshift of z=2.2. The galaxy is known to have properties of a cD galaxy progenitor and be surrounded by a 3 Mpc-sized structure, identified with a protocluster. The morphology shown on the new deep HST ACS image is reminiscent of a spider's w…
Mid-Infrared Spectral Diagnostics of Nuclear and Extranuclear Regions in Nearby Galaxies
Helou, G.; Moustakas, J.; Roussel, H. +19 more
Mid-infrared diagnostics are presented for a large portion of the Spitzer Infrared Nearby Galaxies Survey (SINGS) sample plus archival data from ISO and Spitzer. The SINGS data set includes low- and high-resolution spectral maps and broadband imaging in the infrared for over 160 nuclear and extranuclear regions within 75 nearby galaxies spanning a…
The Outburst of HST-1 in the M87 Jet
Cheung, C. C.; Sparks, W. B.; Wilson, A. S. +4 more
The X-ray intensity of knot HST-1, 0.85" from the nucleus of the radio galaxy M87, has increased by more than a factor of 50 during the last 5 yr. The optical increase is similar, and our more limited radio data indicate a commensurate activity. We give the primary results of our Chandra X-Ray Observatory monitoring program and consider some of th…
The Second IBIS/ISGRI Soft Gamma-Ray Survey Catalog
Hill, A. B.; Mas-Hesse, J. M.; Walter, R. +21 more
In this paper we report the second soft gamma-ray source catalog obtained with the IBIS/ISGRI gamma-ray imager on board the INTEGRAL satellite. The scientific data set is based on more than 10 Ms of high-quality observations performed during the first 2 years of Core Program and public IBIS/ISGRI observations, and covers ~50% of the whole sky. The…
Scaling Mass Profiles around Elliptical Galaxies Observed with Chandra and XMM-Newton
Fukazawa, Y.; Botoya-Nonesa, J. G.; Pu, J. +2 more
We investigated the dynamical structure of 53 elliptical galaxies using the Chandra archival X-ray data. In X-ray-luminous galaxies, temperature increases with radius and gas density is systematically higher at the optical outskirts, indicating the presence of a significant amount of the group-scale hot gas. In contrast, X-ray-dim galaxies show a …
Identification of the Red Supergiant Progenitor of Supernova 2005cs: Do the Progenitors of Type II-P Supernovae Have Low Mass?
Van Dyk, Schuyler D.; Filippenko, Alexei V.; Livio, Mario +5 more
The stars that end their lives as supernovae (SNe) have been directly observed in only a handful of cases, mainly because of the extreme difficulty of identifying them in images obtained prior to the SN explosions. Here we report the identification of the progenitor for the recent Type II-plateau (core collapse) SN 2005cs in pre-explosion archival…