Search Publications
A Detailed Study of Molecular Clouds toward the TeV Gamma-Ray Supernova Remnant G347.3-0.5
Yamaoka, K.; Fukui, Y.; Onishi, T. +4 more
The supernova remnant G347.3-0.5 (J1713.7-3946) is known as one of the unique SNRs that emit TeV γ-rays, as well as nonthermal X-rays. We present a detailed study of molecular gas toward this SNR obtained with the 4 m millimeter and submillimeter telescope NANTEN at an angular resolution of 2.6 arcmin. This study has revealed that several intensit…
On the Origins of Solar EIT Waves
Thompson, B. J.; Laurenza, M.; Cliver, E. W. +1 more
Approximately half of the large-scale coronal waves identified in images obtained by the Extreme-Ultraviolet Imaging Telescope (EIT) on the Solar and Heliospheric Observatory from 1997 March to 1998 June were associated with small solar flares with soft X-ray intensities below C class. The probability of a given flare of this intensity having an a…
The Ionized Gas and Nuclear Environment in NGC 3783. V. Variability and Modeling of the Intrinsic Ultraviolet Absorption
Kaiser, Mary Elizabeth; Brandt, W. N.; Kaspi, Shai +13 more
We present results on the location, physical conditions, and geometry of the outflow in the Seyfert 1 galaxy NGC 3783 from a study of the variable intrinsic UV absorption. Based on analysis of 18 observations with the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope and six observations with the Far Ultraviolet Spectroscopi…
The Stellar Populations of the M31 Halo Substructure
Lewis, Geraint F.; Ibata, Rodrigo A.; Johnston, Kathryn V. +5 more
We present the first results from our survey of stellar substructure in the outskirts of M31 using the Advanced Camera for Surveys on board the Hubble Space Telescope. We discuss the stellar populations associated with five prominent stellar overdensities discovered during the course of our panoramic ground-based imaging survey with the Isaac Newt…
Cassini Visual and Infrared Mapping Spectrometer Observations of Iapetus: Detection of CO2
Sotin, C.; Brown, R. H.; Baines, K. H. +26 more
The Visual and Infrared Mapping Spectrometer (VIMS) instrument aboard the Cassini spacecraft obtained its first spectral map of the satellite Iapetus in which new absorption bands are seen in the spectra of both the low-albedo hemisphere and the H2O ice-rich hemisphere. Carbon dioxide is identified in the low-albedo material, probably a…
Sources of Oscillation Frequency Increase with Rising Solar Activity
Dziembowski, W. A.; Goode, P. R.
We analyze and interpret SOHO MDI data on oscillation frequency changes between 1996 and 2004, focusing on differences between the activity minimum and maximum of solar cycle 23. We study only the behavior of the centroid frequencies, which reflect changes averaged over spherical surfaces. Both the f-mode and p-mode frequencies are correlated with…
The B-Band Luminosity Function of Red and Blue Galaxies up to z = 3.5
Dickinson, M.; Fontana, A.; Cristiani, S. +5 more
We have explored the redshift evolution of the luminosity function of red and blue galaxies up to z=3.5. This was possible by joining a deep I-band composite galaxy sample, which includes the spectroscopic K20 sample and the Hubble Deep Field samples, with the deep HAB=26 and KAB=25 samples derived from the deep NIR images of…
Discovery of a Planetary-Mass Brown Dwarf with a Circumstellar Disk
Luhman, K. L.; Fazio, G. G.; Megeath, S. T. +4 more
Using the Hubble Space Telescope, the 4 m Blanco Telescope at the Cerro Tololo Inter-American Observatory, and the Spitzer Space Telescope, we have performed deep imaging from 0.8 to 8 µm of the southern subcluster in the Chamaeleon I star-forming region. In these data, we have discovered an object, Cha 110913-773444, whose colors and magnit…
A Systematic Search for Gravitationally Lensed Arcs in the Hubble Space Telescope WFPC2 Archive
Smith, Graham P.; Treu, Tommaso; Ellis, Richard S. +1 more
We present the results of a systematic search for gravitationally lensed arcs in clusters of galaxies located in the Hubble Space Telescope Wide Field and Planetary Camera 2 data archive. By carefully examining the images of 128 clusters we have located 12 candidate radial arcs and 104 tangential arcs, each of whose length-to-width ratio exceeds 7…
Simultaneous Ultraviolet and X-Ray Observations of Seyfert Galaxy NGC 4151. I. Physical Conditions in the X-Ray Absorbers
Gull, T. R.; Kriss, G. A.; Turner, T. J. +9 more
We present a detailed analysis of the intrinsic X-ray absorption in the Seyfert 1 galaxy NGC 4151 using Chandra High Energy Transmission Grating Spectrometer data obtained in 2002 May as part of a program that included simultaneous ultraviolet (UV) spectra using the Hubble Space Telescope Space Telescope Imaging Spectrograph and the Far Ultraviole…