Search Publications
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 …
Observations of the X-Ray Afterglows of GRB 011211 and GRB 001025 by XMM-Newton
Trudolyubov, Sergey P.; Borozdin, Konstantin N.
We present the XMM-Newton observations of X-ray afterglows of the gamma-ray bursts GRB 011211 and GRB 001025. For GRB 011211, XMM detected a fading X-ray object with an average flux in 0.2-10 keV declining from 2.7×10-13 ergs s-1 cm-2 during the first 5 ks of the 27 ks observation to 1.0×10-13 ergs s
ROSAT View of Hipparcos F Stars
Makarov, V. V.; Voges, W.; Suchkov, A. A.
For a set of 11,900 F stars that have uvby photometry and are in the Hipparcos catalog, we have found 1980 X-ray counterparts (~17%) in the ROSAT All-Sky Survey (RASS). In this paper we analyze X-ray properties of these ROSAT F stars and compare that sample with the entire set of our F stars. The comparison has shown that the ROSAT F stars are on …
A Probable Dwarf Nova Outburst in the Core of the Globular Cluster M22
Anderson, Jay; Cool, Adrienne M.; King, Ivan R.
We reexamine an event that was previously reported by Sahu et al. as a microlensing event of a Galactic bulge star by a star of M22. We find strong evidence that the event was actually a dwarf nova outburst of a cataclysmic variable in the cluster. The primary evidence consists of the star's proper motion, Hα emission, X-ray luminosity, and variab…