Search Publications
Dusty Blast Waves of Two Young Large Magellanic Cloud Supernova Remnants: Constraints on Post-shock Compression
Blair, William P.; Reynolds, Stephen P.; Points, Sean +9 more
We present results from mid-IR spectroscopic observations of two young supernova remnants (SNRs) in the Large Magellanic Cloud made with the Spitzer Space Telescope. We imaged SNRs B0509-67.5 and B0519-69.0 with Spitzer in 2005, and follow-up spectroscopy presented here confirms the presence of warm, shock-heated dust, with no lines present in the…
Critical Differences and Clues in Eta Car's 2009 Event
Humphreys, Roberta M.; Davidson, Kris; Mehner, Andrea +3 more
We monitored Eta Carinae with the Hubble Space Telescope WFPC2 and Gemini GMOS throughout the 2009 spectroscopic event, which was expected to differ from its predecessor in 2003. Here we report major observed differences between events and their implications. Some of these results were quite unexpected. (1) The UV brightness minimum was much deepe…
The Redshift and Nature of AzTEC/COSMOS 1: A Starburst Galaxy at z = 4.6
Kneib, J. -P.; Berta, S.; Lutz, D. +36 more
Based on broadband/narrowband photometry and Keck DEIMOS spectroscopy, we report a redshift of z = 4.64+0.06 -0.08 for AzTEC/COSMOS 1, the brightest submillimeter galaxy (SMG) in the AzTEC/COSMOS field. In addition to the COSMOS-survey X-ray to radio data, we report observations of the source with Herschel/PACS (100, 160 &mic…
The Deepest Hubble Space Telescope Color-Magnitude Diagram of M32. Evidence for Intermediate-age Populations
Monachesi, Antonela; Lauer, Tod R.; Dressler, Alan +4 more
We present the deepest optical color-magnitude diagram (CMD) to date of the local elliptical galaxy M32. We have obtained F435W and F555W photometries based on Hubble Space Telescope (HST) Advanced Camera for Surveys/High-Resolution Channel images for a region 110'' from the center of M32 (F1) and a background field (F2) about 320'' away from M32 …
Black Holes in Bulgeless Galaxies: An XMM-Newton Investigation of NGC 3367 and NGC 4536
Cheung, C. C.; Eracleous, Michael; Satyapal, S. +3 more
The vast majority of optically identified active galactic nuclei (AGNs) in the local universe reside in host galaxies with prominent bulges, supporting the hypothesis that black hole formation and growth is fundamentally connected to the buildup of galaxy bulges. However, recent mid-infrared spectroscopic studies with Spitzer of a sample of optica…
Evidence for Black Hole Growth in Local Analogs to Lyman Break Galaxies
Heckman, Timothy M.; Hornschemeier, Ann; Overzier, Roderik A. +3 more
We have used XMM-Newton to observe six Lyman break analogs (LBAs): members of the rare population of local galaxies that have properties that are very similar to distant Lyman break galaxies. Our six targets were specifically selected because they have optical emission-line properties that are intermediate between starbursts and Type 2 (obscured) …
A Coherent Timing Solution for the Nearby, Thermally Emitting Isolated Neutron Star RX J0420.0-5022
van Kerkwijk, M. H.; Kaplan, D. L.
We present a phase-coherent timing solution for RX J0420.0-5022, the coolest (kT ~= 45 eV) and fastest-spinning (P = 3.45 s) of the seven so-called isolated neutron stars (INSs). Using 14 observations with the XMM-Newton spacecraft in 2010 and 2011, we were able to measure a spin-down rate \dot{\nu }=(-2.3+/- 0.2)\times 10^{-15}\,{\,Hz\,s}^{-1} (\…
Millimeter Imaging of the β Pictoris Debris Disk: Evidence for a Planetesimal Belt
Hughes, A. Meredith; Wilner, David J.; Andrews, Sean M.
We present observations at 1.3 mm wavelength of the β Pictoris debris disk with beam size 4farcs3 × 2farcs6 (83 × 50 AU) from the Submillimeter Array. The emission shows two peaks separated by ~7'' along the disk plane, which we interpret as a highly inclined dust ring or belt. A simple model constrains the belt center to 94 ± 8 AU, close to the p…
Spatially Resolving the HK Tau B Edge-on Disk from 1.2 to 4.7 µm: A Unique Scattered Light Disk
Pinte, C.; Ménard, F.; Duchêne, G. +3 more
We present spatially resolved scattered light images of the circumstellar disk around HK Tau B at 3.8 and 4.7 µm taken with the Keck Telescope Laser Guide Star Adaptive Optics (AO) system, and 1.6-2.12 µm images taken with the Very Large Telescope/NACO AO system. Combined with previously published optical Hubble Space Telescope data, w…
Resolving the Baryon-fraction Profile in Lensing Galaxies
Saha, Prasenjit; Ferreras, Ignacio; Falco, Emilio E. +1 more
The study of the distribution of baryonic matter within dark halos enriches our understanding of galaxy formation. We show the radial dependence of stellar baryon-fraction curves derived for 21 lensing galaxies from the CfA-Arizona Space Telescope LEns Survey (CASTLES) by means of stellar population synthesis and pixel-based mass reconstruction. T…