Search Publications
Quiescent Giant Molecular Cloud Cores in the Galactic Center
Li, Y.; Lis, D. C.; Zylka, R. +1 more
We have used the Long Wavelength Spectrometer aboard the Infrared Space Observatory to map the far-infrared continuum emission (45-175 µm) toward several massive giant molecular cloud (GMC) cores located near the Galactic center. The observed far-infrared and submillimeter spectral energy distributions imply low temperatures (~15-22 K) for t…
Chandra, EUVE, HST, and VLA Multiwavelength Campaign on HR 1099: Instrumental Capabilities, Data Reduction, and Initial Results
Ayres, Thomas R.; Brown, Alexander; Drake, Jeremy J. +4 more
In mid-September of 1999, a multiwavelength campaign was carried out on the coronally active RS Canum Venaticorum binary HR 1099 (K1 IV+G5 V P=2.84 days), during commissioning of the High Energy Transmission Grating Spectrometer (HETGS) of the Chandra X-ray Observatory (CXO). The coordinated program involved the Extreme Ultraviolet Explorer (EUVE)…
Space Telescope Imaging Spectrograph Echelle Observations of the Seyfert Galaxy NGC 4151: Physical Conditions in the Ultraviolet Absorbers
Gull, T. R.; Kraemer, S. B.; Crenshaw, D. M. +7 more
We have examined the physical conditions in intrinsic UV-absorbing gas in the Seyfert galaxy NGC 4151, using echelle spectra obtained with the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope on 1999 July 19. We confirm the presence of the kinematic components detected in earlier Goddard High Resolution Spectrograph (GHRS)…
The Southern Crab from a New Perspective
Livio, Mario; Corradi, Romano L. M.; Munari, Ulisse +2 more
New Hubble Space Telescope images and Cerro Tololo Inter-American Observatory echelle spectra of the nebula around the symbiotic Mira Henize 2-104 are presented. The nebula consists of two nested hourglass-shaped structures and a collimated polar jet. Spatiokinematical modeling shows that all three outflows were ejected during approximately the sa…
Coronal Mass Ejection of 2000 July 14 Flare Event: Imaging from Near-Sun to Earth Environment
Pick, M.; Kaiser, M. L.; Ipavich, F. M. +6 more
We report the results of our investigation of interplanetary effects caused by the large solar flare (X5.7/3B) that occurred on 2000 July 14. In association with this event a bright, fast, halo coronal mass ejection (CME) was observed. The analysis of multiwavelength, high-cadence images obtained from the Nançay Radioheliograph shows the on-disk s…
Temporal Variations of the Solar Rotation Rate at High Latitudes
Basu, Sarbani; Antia, H. M.
Frequency splitting coefficients from Global Oscillation Network Group and Michelson Doppler Imager observations covering the period 1995-2001 are used to study temporal variations in the solar rotation rate at high latitudes. The torsional oscillation pattern in the Sun is known to penetrate to a depth of about 0.1 Rsolar with alternat…
Physical Parameters of Erupting Luminous Blue Variables: NGC 2363-V1 Caught in the Act
Drissen, Laurent; Robert, Carmelle; Smith, Linda J. +3 more
A quantitative study of the luminous blue variable NGC 2363-V1 in the Magellanic galaxy NGC 2366 (D=3.44 Mpc) is presented, based on ultraviolet and optical Hubble Space Telescope STIS spectroscopy. Contemporary WFPC2 and William Herschel Telescope imaging reveals a modest V-band brightness increase of ~0.2 mag per year between 1996 January-1997 N…
Locating the Starburst in the SCUBA Galaxy SMM J14011+0252
Kneib, J. -P.; Ivison, R. J.; Frayer, D. T. +2 more
We present new, multiwavelength, high-resolution imaging of the luminous, submillimeter galaxy SMM J14011+0252, an interacting starburst at z=2.56. Our observations comprise optical imaging from the Hubble Space Telescope, sensitive radio mapping from the Very Large Array, and CO observations from the Owens Valley Radio Observatory and Berkeley-Il…
Absorption and Reddening in the Seyfert Galaxy NGC 3227
Kraemer, S. B.; Crenshaw, D. M.; Bruhweiler, F. C. +1 more
We have obtained low-dispersion spectra of NGC 3227 with the Space Telescope Imaging Spectrograph (STIS) to study the intrinsic UV absorption and the reddening of the nucleus in this Seyfert 1 galaxy. The UV spectra show a wealth of absorption lines at the systemic redshift that span a wide range in ionization state (Mg I to N V). The equivalent w…
A Possible Massive Asteroid Belt around ζ Leporis
Jura, M.; Chen, C. H.
We have used the Keck I telescope to image at 11.7 and 17.9 µm the dust emission around ζ Leporis, a main-sequence A-type star at 21.5 pc from the Sun with an infrared excess. The excess is at most marginally resolved at 17.9 µm. The dust distance from the star is probably <=6 AU, although some dust may extend to 9 AU. The mass of o…