Search Publications
Ultraviolet Spectroscopy of Narrow Coronal Mass Ejections
Raymond, J. C.; Dobrzycka, D.; Biesecker, D. A. +2 more
We present Ultraviolet Coronagraph Spectrometer (UVCS) observations of five narrow coronal mass ejections (CMEs) that were among 15 narrow CMEs originally selected by Gilbert and coworkers. Two events (1999 March 27, April 15) were ``structured,'' i.e., in white-light data they exhibited well-defined interior features, and three (1999 May 9, May 2…
The 2001 April Burst Activation of SGR 1900+14: X-Ray Afterglow Emission
Hurley, K.; Costa, E.; Mereghetti, S. +8 more
After nearly two years of quiescence, the soft gamma-ray repeater SGR 1900+14 again became burst-active on 2001 April 18, when it emitted a large flare, preceded by few weak and soft short bursts. After having detected the X- and gamma-prompt emission of the flare, BeppoSAX pointed its narrow field X-ray telescopes to the source in less than 8 hr.…
A Scattered Light Echo around SN 1993J in M81
Bregman, Joel N.; Seitzer, Patrick; Liu, Ji-Feng
A light echo around SN 1993J was observed 8.2 yr after explosion by a Hubble Space Telescope Wide Field Planetary Camera 2 observation, adding to the small family of supernovae with light echoes. The light echo was formed by supernova light scattered from a dust sheet that lies 220 pc away from the supernova, 50 pc thick along the line of sight, a…
The Line Emission Region in III Zw 2: Kinematics and Variability
Bon, E.; Popović, L. Č.; Mediavilla, E. G. +2 more
We have studied the Lyα, Hβ, Hα, and Mg II λ2798 line profiles of the Seyfert 1 galaxy III Zw 2. The shapes of these broad emission lines show evidence of a multicomponent origin and also features that may be identified as the peaks due to a rotating disk. We have proposed a two-component broad-line region (BLR) model consisting of an inner Kepler…
X-Ray Emission from the Pre-planetary Nebula Henize 3-1475
Frank, Adam; Kastner, Joel H.; Sahai, Raghvendra +2 more
We report the first detection of X-ray emission in a pre-planetary nebula, He 3-1475. Pre-planetary nebulae are rare objects in the short transition stage between the asymptotic giant branch (AGB) and planetary nebula evolutionary phases, and He 3-1475, characterized by a remarkable S-shaped chain of optical knots, is one of the most noteworthy me…
Emission and Absorption in the M87 LINER
Filippenko, Alexei V.; Ho, Luis C.; Shields, Joseph C. +2 more
The nucleus of M87 displays a LINER spectrum at optical wavelengths, with a nuclear disk of nebulosity that is resolved by the Hubble Space Telescope (HST). We present new results from optical and ultraviolet spectra of the central ~40 pc as measured by HST. In contrast with previous results for the extended disk, the emission-line spectrum of the…
Infrared Spectroscopy of 15 Radio Galaxies at 2<z<2.6
Motohara, Kentaro; Iwamuro, Fumihide; Maihara, Toshinori +7 more
Near-infrared spectra of 15 high-redshift radio galaxies (HzRGs) located at 2<z<2.6 were obtained by the OH Airglow Suppressor spectrograph mounted on the Subaru telescope. The UV-optical line ratio diagnostic diagrams indicate that half of the observed HzRGs have extended emission-line regions with low metal abundance, photoionized by a fla…
Hubble Space Telescope STIS Spectrum of RW Aurigae A: Evidence for an Ionized Beltlike Structure and Mass Ejection in Timescales of a Few Hours
Gómez de Castro, Ana I.; Verdugo, Eva
Profiles of the UV semiforbidden lines of C III]1908 and Si III]1892 of RW Aur have been obtained with the Hubble Space Telescope (HST) STIS. The C III]1908 profile shows two high-velocity components at v=+/-170 km s-1 and a central one. The Si III]1892 profile is very broad (FWHM = 293 km s
Multiple Molecular H2 Outflows in AFGL 618
Bachiller, R.; Forveille, T.; Cox, P. +3 more
We report high spatial (0.5") and high spectral (9 km s-1) resolution spectro-imaging of the 2.12 µm H2 1-->0 S(1) line in the proto-planetary nebula AFGL 618 using BEAR at the Canada-France-Hawaii Telescope. The observations reveal the presence of multiple, high-velocity, molecular outflows that align with the remar…
The Dust Ring of Luminous Blue Variable Candidate HD 168625: Infrared Observations and Model Calculations
Ueta, Toshiya; Meixner, Margaret; Bobrowsky, Matthew +2 more
We present a 2.218 µm image from the Hubble Space Telescope/Near Infrared Camera and Multi-Object Spectrometer (NICMOS) and a 55 µm image from ISOPHOT of the dust ring surrounding the luminous blue variable (LBV) candidate HD 168625, together with new temperature and optical depth maps derived from mid-IR images. The shell is detached …