Science Archives Publication System

Nobeyama Millimeter Array CO (J=1-0) Observations of the Hα/Radio Lobe Galaxy NGC 3079: Gas Dynamics in a Weak Bar Potential and Central Massive Core

DOI: 10.1086/340561 Bibcode: 2002ApJ...573..105K

Kohno, K.; Koda, J.; Sofue, Y. +4 more

We present ¹²CO (1-0) observations in the central 4.5 kpc (1') of the Hα/radio lobe galaxy NGC 3079 with the Nobeyama Millimeter Array. The molecular gas shows four components: a main disk, spiral arms, a nuclear disk, and a nuclear core. The main disk extends along the galaxy major axis. We detected its central 2 kpc radius, while its …

2002 • The Astrophysical Journal

eHST 45

Hubble Space Telescope Expansion Parallaxes of the Planetary Nebulae NGC 6578, NGC 6884, NGC 6891, and IC 2448

DOI: 10.1086/339838 Bibcode: 2002AJ....123.2666P

Bond, Howard E.; Panagia, Nino; Balick, Bruce +3 more

We have combined two epochs of Hubble Space Telescope WFPC2 imaging data with ground-based expansion velocities to determine distances to three planetary nebulae (NGC 6578, NGC 6884, and IC 2448). We used two variants of the expansion parallax technique-a gradient method and a magnification method-to determine the distances. The results from the t…

2002 • The Astronomical Journal

eHST 45

Cosmic Alignment toward the Radio Einstein Ring PKS 1830-211?

DOI: 10.1086/341261 Bibcode: 2002ApJ...575...95C

Kneib, J. -P.; Lidman, C.; Meylan, G. +1 more

Optical and near-IR Hubble Space Telescope and Gemini North adaptive optics images, further improved through deconvolution, are used to explore the gravitationally lensed radio source PKS 1830-211. The line of sight to the quasar at z=2.507 appears to be very busy, with the presence, within 0.5" from the source, of (1) a possible galactic main-seq…

2002 • The Astrophysical Journal

eHST 45

The Phoenix galaxy: UGC 4203 re-birth from its ashes?

DOI: 10.1051/0004-6361:20020471 Bibcode: 2002A&A...388..787G

Perola, G. C.; Fiore, F.; Guainazzi, M. +1 more

We report on a dramatic transition between a Compton-thick, reflection-dominated state and a Compton-thin state in the Seyfert 2 galaxy UGC 4203, discovered by comparing a recent (May 2001) XMM-Newton observation with ASCA observations performed about six years earlier. This transition can be explained either as a change in the column density of t…

2002 • Astronomy and Astrophysics

XMM-Newton 45

Interplanetary radio emission due to interaction between two coronal mass ejections

DOI: 10.1029/2001GL013606 Bibcode: 2002GeoRL..29.1265G

Gopalswamy, Nat; Howard, Russell A.; Yashiro, Seiji +2 more

We report on the detection of a new class of nonthermal radio emission due to the interaction between two coronal mass ejections (CMEs). The radio emission was detected by the Radio and Plasma Wave Experiment (WAVES) on board the Wind satellite, while the CMEs were observed by the white-light coronagraphs of the Solar and Heliospheric Observatory …

2002 • Geophysical Research Letters

SOHO 45

Hubble Space Telescope/WFPC2 Images of the GG Tauri Circumbinary Disk

DOI: 10.1086/339777 Bibcode: 2002ApJ...570..785K

Krist, John E.; Stapelfeldt, Karl R.; Watson, Alan M.

We present the first visible wavelength images of the GG Tau circumbinary ring obtained with the Hubble Space Telescope's (HST) Wide Field and Planetary Camera 2. Scattered light from the ring is detected in both V- and I-band images. The images show that the ring is smooth, except for a small gap that could be a shadow caused by material between …

2002 • The Astrophysical Journal

eHST 45

Energy Transformation Mechanism in the Solar Atmosphere Associated with Magnetofluid Coupling: Explosive and Eruptive Events

DOI: 10.1086/339499 Bibcode: 2002ApJ...570..395O

Ohsaki, Shuichi; Shatashvili, Nana L.; Yoshida, Zensho +1 more

By modeling the closed field structures in the solar atmosphere by ``slowly'' evolving double Beltrami two-fluid equilibria (created by the interaction of the magnetic and velocity fields), the conditions for catastrophic transformations of the original state are derived. The analysis for predicting sudden changes is carried out through a set of a…

2002 • The Astrophysical Journal

SOHO 45

The Next Geminga: Deep Multiwavelength Observations of a Neutron Star Identified with 3EG J1835+5918

DOI: 10.1086/341967 Bibcode: 2002ApJ...573L..41H

Mirabal, N.; Camilo, F.; Gotthelf, E. V. +1 more

We describe Chandra, Hubble Space Telescope (HST), and radio observations that reveal a radio-quiet but magnetospherically active neutron star in the error circle of the high-energy γ-ray source 3EG J1835+5918, the brightest of the unidentified EGRET sources at high Galactic latitude. A Chandra ACIS-S spectrum of the ultrasoft X-ray source RX J183…

2002 • The Astrophysical Journal

eHST 45

Interstellar Deuterium, Nitrogen, and Oxygen Abundances toward BD +28°4211: Results from the FUSE Mission

DOI: 10.1086/339134 Bibcode: 2002ApJS..140...51S

Tripp, Todd M.; Jenkins, Edward B.; Sembach, Kenneth R. +12 more

High-resolution far-UV spectra of the O-type subdwarf BD +28°4211 were obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE) to measure the interstellar deuterium, nitrogen, and oxygen abundances in this direction. The interstellar D I transitions are analyzed down to Lyι at 920.7 Å. The star was observed several times at different targe…

2002 • The Astrophysical Journal Supplement Series

eHST 45

The Origin of Fe II and [Fe II] Emission Lines in the 4000-10000 Å Range in the BD Weigelt Blobs of η Carinae

DOI: 10.1086/344443 Bibcode: 2002ApJ...581.1154V

Davidson, K.; Gull, T. R.; Bruhweiler, F. +3 more

We present numerical simulations that reproduce the salient features of the amazingly strong [Fe II] and Fe II emission spectra in the B and D Weigelt blobs of η Carinae. For our studies we have used spectra obtained during the 1998 epoch observations with the Hubble Space Telescope (HST). The spectrum of the B and D Weigelt blobs dominates in [Fe…

2002 • The Astrophysical Journal

eHST 45