Search Publications
How Many Active Galaxies and QSOs Will Future Space Missions Detect?
Spinoglio, Luigi; Malkan, Matthew A.; Andreani, Paola
Averaged spectral energy distributions (SEDs) of active and starburst galaxies, from the 12 µm sample in the local universe, and QSOs, from an optically selected sample at a mean redshift <z>=0.7, are built from optical, near-IR, and far-IR (FIR; IRAS and Infrared Space Observatory) photometric observations. These SEDs are then used to…
The Infrared Spectral Energy Distribution of the Seyfert 2 Prototype NGC 5252
Acosta-Pulido, J. A.; Prieto, M. Almudena
The complete mid- to far-infrared continuum energy distribution collected with the Infrared Space Observatory of the Seyfert 2 prototype NGC 5252 is presented. ISOCAM images taken in the 3-15 µm show a resolved central source that is consistent at all bands with a region of about 1.3 kpc in size. Because of the lack of ongoing star formation…
Azimuthal and Kinematic Segregation of Neutral and Molecular Gas in Arp 118: The Yin-Yang Galaxy NGC 1144
Appleton, P. N.; Charmandaris, V.; Gao, Yu +2 more
We present new high-resolution H I observations of the disk of the collisional infrared luminous (LIR=2.2×1011Lsolar) galaxy NGC 1144, which reveal an apparent large-scale azimuthal and kinematic segregation of neutral hydrogen relative to the molecular gas distribution. Even among violently collisional galaxies, t…
Temperature Measurements in the Solar Transition Region Using N III Line Intensity Ratios
Bhatia, A. K.; Doschek, G. A.; Feldman, U. +2 more
UV emission from B-like N and O ions offers a rather rare opportunity for recording spectral lines in a narrow wavelength range that can potentially be used to derive temperatures relevant to the solar transition region. In these ions, the line intensity ratios of the type (2s2p2-2p3)/(2s22p-2s2p2) are v…
Shadowing of the Nascent Jet in NGC 4261 by a Line-emitting Supersonic Accretion Disk
Fromerth, Michael J.; Melia, Fulvio; Liu, Siming
NGC 4261 (3C 270) is a low-luminosity radio galaxy with two symmetric kiloparsec-scale jets. Earlier Hubble Space Telescope observations indicated the presence of a 100 pc scale disk of cool dust and gas surrounding a central, supermassive (~4.9×108 Msolar) black hole. The recent detection of free-free radio absorption by a s…
High-Redshift Candidates and the Nature of Small Galaxies in the Hubble Deep Field
Thompson, Rodger I.; Weymann, Ray J.; Storrie-Lombardi, Lisa J.
We present results on two related topics: (1) a discussion of high-redshift candidates (z>4.5) and (2) a study of very small galaxies at intermediate redshifts, both sets being detected in the region of the northern Hubble Deep Field (HDF) covered by the deep NICMOS observations at 1.6 and 1.1 µm. The high-redshift candidates are just tho…
Beyond the Hubble Deep Field Limiting Magnitude: Faint Galaxy Number Counts from Surface Brightness Fluctuations
Marín-Franch, A.; Aparicio, A.
The faint end of the differential galaxy number counts n(m) in the Hubble Deep Field-North (HDF-N) has been determined for the F450W, F606W, and F814W filters by means of surface brightness fluctuation measurements. This technique allows us to explore n(m) beyond the limiting magnitude of the HDF, providing new, stronger constraints on the faint e…