Search Publications
BAT X-Ray Survey. I. Methodology and X-Ray Identification
Greiner, J.; Strong, A. W.; Ajello, M. +3 more
We applied the maximum likelihood (ML) method, as an image reconstruction algorithm, to the BAT X-Ray Survey (BXS). This method was specifically designed to preserve the full statistical information in the data and to avoid mosaicking of many exposures with different pointing directions, thus reducing systematic errors when co-adding images. We re…
Strongly Blueshifted Phenomena Observed with Hinode EIS in the 2006 December 13 Solar Flare
Culhane, J. L.; Hara, Hirohisa; Narukage, Noriyuki +5 more
We present a detailed examination of strongly blueshifted emission lines observed with the EUV Imaging Spectrometer on board the Hinode satellite. We found two kinds of blueshifted phenomenon associated with the X3.4 flare that occurred on 2006 December 13. One was related to a plasmoid ejection seen in soft X-rays. It was very bright in all the l…
HST ACS Imaging of M82: A Comparison of Mass and Size Distribution Functions of the Younger Nuclear and Older Disk Clusters
Luna, A.; Mayya, Y. D.; Rosa-González, D. +3 more
We present the results obtained from an objective search for stellar clusters, both in the currently active nuclear starburst region, and in the poststarburst disk of M82. Images obtained with the Advanced Camera for Surveys (ACS) on board the Hubble Space Telescope (HST) in F435W (B), F555W (V), and F814W (I) filters were used in the search for t…
A Search for Molecular Gas in the Nucleus of M87 and Implications for the Fueling of Supermassive Black Holes
Beuther, Henrik; Walter, Fabian; Tan, Jonathan C. +1 more
Supermassive black holes in giant elliptical galaxies are remarkably faint given their expected accretion rates. This motivates models of radiatively inefficient accretion due to either ion-electron thermal decoupling, generation of outflows that inhibit accretion, or settling of gas to a gravitationally unstable disk that forms stars in preferenc…
Emission from Very Small Grains and PAH Molecules in Monte Carlo Radiation Transfer Codes: Application to the Edge-On Disk of Gomez's Hamburger
Wood, Kenneth; Robitaille, Thomas; Draine, Bruce T. +1 more
We have modeled optical to far-infrared images, photometry, and spectroscopy of the object known as Gomez's Hamburger. We reproduce the images and spectrum with an edge-on disk of mass 0.3 M⊙ and radius 1600 AU, surrounding an A0 III star at a distance of 280 pc. Our mass estimate is in excellent agreement with recent CO observations. H…
A New FUSE Survey of Interstellar HD
Snow, Theodore P.; Destree, Joshua D.; Rachford, Brian L. +5 more
We have used archival FUSE data to complete a survey of interstellar HD in 41 lines of sight with a wide range of extinctions. This follow-up to an earlier survey was made to further assess the utility of HD as a cosmological probe; to analyze the HD formation process; and to see what trends with other interstellar properties were present in the d…
Off-Nuclear Star Formation and Obscured Activity in the Luminous Infrared Galaxy NGC 2623
Sanders, D. B.; Surace, J. A.; Armus, L. +13 more
New optical Hubble Space Telescope (HST), Spitzer Space Telescope, and XMM observations of the luminous infrared galaxy (LIRG) NGC 2623 are presented. This galaxy was observed as part of the Great Observatories All-sky LIRG Survey (GOALS). The prominent 3.2 kpc southern extension to the nucleus has been resolved by HST observations into ~100 star …
GRB 070610: A Curious Galactic Transient
Cenko, S. B.; Campana, S.; Price, P. A. +23 more
GRB 070610 is a typical high-energy event with a duration of 5 s. Yet within the burst localization we detect a highly unusual X-ray and optical transient, Swift J195509.6+261406. We see high-amplitude X-ray and optical variability on very short timescales even at late times. Using near-infrared imaging assisted by a laser guide star and adaptive …
The Structure of the Local Interstellar Medium. V. Electron Densities
Redfield, Seth; Falcon, Ross E.
We present a comprehensive survey of C II* absorption detections toward stars within 100 pc in order to measure the distribution of electron densities present in the local interstellar medium (LISM). Using high spectral resolution observations obtained by GHRS and STIS on board HST, we searched for all detections of LISM C II* absorption. We ident…
Coronal Rotation at Solar Minimum from UV Observations
Giordano, S.; Mancuso, S.
The observations of the UVCS SOHO instrument from 1996 May to 1997 May have been analyzed to reconstruct intensity time series of the O VI 1032 Å and H I Lyα 1216 Å spectral lines at different coronal heliolatitudes from 1.5 to 3.0 R⊙ from Sun center. At solar minimum, some features persist for several rotations, thus allowing analysis …