Science Archives Publication System

Multiple Collimated Outflows in the Proto-Planetary Nebula GL 618

DOI: 10.1086/342943 Bibcode: 2002ApJ...579..688T

Trammell, Susan R.; Goodrich, Robert W.

We present narrowband Hα, [S II], and [O I] Hubble Space Telescope images of the young planetary nebula GL 618. This object is a compact, bipolar nebula that is currently undergoing the transition from asymptotic giant branch star to planetary nebula. Our images confirm the presence of at least three highly collimated outflows emanating from the c…

2002 • The Astrophysical Journal

eHST 36

A chromospheric scenario for the activity of beta Pictoris, as revealed by FUSE

DOI: 10.1051/0004-6361:20020741 Bibcode: 2002A&A...390.1049B

Deleuil, M.; Bouret, J. -C.; Roberge, A. +3 more

We investigate a chromospheric scenario to explain the characteristics of the far-UV emission lines of beta Pictoris, revealed by FUSE spectra of this famous circumstellar disk system. The model assumes a thin region heated up to a few 10⁵ K located close to the stellar photosphere. The resonance lines of C III at 977 Å and O VI at 1032…

2002 • Astronomy and Astrophysics

eHST 36

Detection of the Neupert Effect in the Corona of an RS Canum Venaticorum Binary System by XMM-Newton and the Very Large Array

DOI: 10.1086/342122 Bibcode: 2002ApJ...577..371G

Güdel, Manuel; Behar, Ehud; Audard, Marc +3 more

The RS CVn-type binary σ Geminorum was observed during a large, long-duration flare simultaneously with XMM-Newton and the Very Large Array. The light curves show a characteristic time dependence that is compatible with the Neupert effect observed in solar flares: the time derivative of the X-ray light curve resembles the radio light curve. This o…

2002 • The Astrophysical Journal

XMM-Newton 36

Hipparcos open clusters and stellar evolution

DOI: 10.1046/j.1365-8711.2002.05508.x Bibcode: 2002MNRAS.334..193C

Prada Moroni, P. G.; Degl'Innocenti, S.; Castellani, V. +1 more

By relying on recently improved Hipparcos parallaxes for the Hyades, Pleiades and Ursa Major clusters we find that stellar models with updated physical inputs reproduce nicely the location in the colour-magnitude diagram of main-sequence stars of different metallicities. Stars in the helium-burning phase are also discussed, showing that the lumino…

2002 • Monthly Notices of the Royal Astronomical Society

Hipparcos 36

Dual-filament initiation of a Coronal Mass Ejection: Observations and Model

DOI: 10.1023/A:1019610614255 Bibcode: 2002SoPh..208...69U

Grechnev, V. V.; Uralov, A. M.; Lesovoi, S. V. +1 more

We propose a new model for the initiation of solar coronal mass ejections (CMEs) and CME-associated flares. The model is inferred from observations of a quiescent filament eruption in the north-western quadrant of the solar disk on 4 September 2000. The event was observed with the Siberian Solar Radio Telescope (5.7 GHz), the Nobeyama Radioheliogr…

2002 • Solar Physics

SOHO 36

A New Measurement of the Average Far-Ultraviolet Extinction Curve

DOI: 10.1086/337955 Bibcode: 2002ApJ...566..267S

Hurwitz, M.; Dixon, W. V.; Sasseen, T. P. +1 more

We have measured the extinction curve in the far-ultraviolet wavelength region of (900-1200 Å) using spectra obtained with the Berkeley EUV/FUV spectrometer during the ORFEUS I and the ORFEUS II (Orbiting and Retrievable Far and Extreme Ultraviolet Spectrometer) missions in 1993 and 1996. From the complete sample of early-type stars observed durin…

2002 • The Astrophysical Journal

IUE 36

XMM-Newton observations of the isolated neutron star RX J0806.4-4123

DOI: 10.1051/0004-6361:20020778 Bibcode: 2002A&A...391..571H

Haberl, F.; Zavlin, V. E.

The isolated neutron star RX J0806.4-4123 was observed with XMM-Newton in November 2000. The data from the three EPIC instruments allowed us (i) to derive an improved X-ray position to an accuracy of 2-3 arcsec, (ii) to accumulate the first medium-resolution soft X-ray spectra of high statistical quality and (iii) to find a cand…

2002 • Astronomy and Astrophysics

XMM-Newton 36

Transition Region Blinkers I. Quiet-Sun Properties

DOI: 10.1023/A:1014954629349 Bibcode: 2002SoPh..206...21B

Harrison, R. A.; Parnell, C. E.; Bewsher, D.

An automated method of identifying transition region blinkers is presented. The distribution and general properties of blinkers identified in the quiet Sun are discussed. The blinkers are seen most clearly in the O v (629 Å) transition region emission line, but they also have strong signatures in O iv (554 Å), and the chromospheric line, He i (584…

2002 • Solar Physics

SOHO 36

Isolating Clusters with Wolf-Rayet Stars in I Zw 18

DOI: 10.1086/345336 Bibcode: 2002ApJ...579L..75B

Brown, Thomas M.; Hubeny, Ivan; Heap, Sara R. +2 more

We present UV images and spectra of the starburst galaxy I Zw 18, taken with the Space Telescope Imaging Spectrograph. The high spatial resolution of these data allows us to isolate clusters containing Wolf-Rayet stars of the subtype WC. Our far-UV spectra clearly show C IV λλ1548, 1551 and He II λ1640 emission of WC stars in two clusters: one wit…

2002 • The Astrophysical Journal

eHST 36

High-Resolution X-ray imaging and spectroscopy of N 103B

DOI: 10.1051/0004-6361:20020963 Bibcode: 2002A&A...392..955V

Kaastra, J. S.; Mewe, R.; Behar, E. +5 more

The X-ray emission from the young supernova remnant (SNR) N 103B is measured and analysed using the high-resolution cameras and spectrometers on board XMM-Newton and Chandra. The spectrum from the entire remnant is reproduced very well with three plasma components of kT_e = 0.55, 0.65, and 3.5 keV, corresponding roughly to line emission …

2002 • Astronomy and Astrophysics

XMM-Newton 36