Science Archives Publication System

HV Ursae Majoris, a new contact binary with early-type components

DOI: 10.48550/arXiv.astro-ph/0002379 Bibcode: 2000A&A...356..603C

Kiss, L. L.; Alfaro, E. J.; Csák, B. +1 more

We present the first UBV and uvby photometric observations for the short period variable star HV Ursae Majoris classified as a field RRc variable. The observed differences between the consecutive minima and the lack of colour variations disagree with the RRc-classification and suggest the possible binary nature of HV UMa. In order to reveal the re…

2000 • Astronomy and Astrophysics

Hipparcos 20

Multi-wavelength observations and modelling of shock-cloud interaction regions in the Vela Supernova Remnant

Bibcode: 2000A&A...359..316B

Bocchino, F.; Sciortino, S.; Raymond, J. +1 more

We present optical photometric and spectrophotometric observations of two selected filaments near the North rim of the Vela supernova remnant also observed in UV with the International Ultraviolet Explorer, and in X-rays with the ROSAT PSPC detector. From the optical data, we have derived spatially-resolved ( ~ 3^'') profiles of several …

2000 • Astronomy and Astrophysics

IUE 20

Detection and Mapping of Decoupled Stellar and Ionized Gas Structures in the Ultraluminous Infrared Galaxy IRAS 12112+0305

DOI: 10.1086/312590 Bibcode: 2000ApJ...533L...9C

Arribas, Santiago; Colina, Luis; Borne, Kirk D. +1 more

Integral field optical spectroscopy with the INTEGRAL fiber-fed system and Hubble Space Telescope optical imaging are used to map the complex stellar and warm ionized gas structure in the ultraluminous infrared galaxy IRAS 12112+0305. Images reconstructed from wavelength-delimited extractions of the integral field spectra reveal that the observed …

2000 • The Astrophysical Journal

eHST 20

Solar Cycle Variations of Large-Scale Flows in the sun

DOI: 10.1023/A:1005256817534 Bibcode: 2000SoPh..192..469B

Basu, Sarbani; Antia, H. M.

Using data from the Michelson Doppler Imager (MDI) instrument on board the Solar and Heliospheric Observatory (SOHO), we study the large-scale velocity fields in the outer part of the solar convection zone using the ring diagram technique. We use observations from four different times to study possible temporal variations in flow velocity. We find…

2000 • Solar Physics

SOHO 20

The INES system. II. Ripple correction and absolute calibration for IUE high resolution spectra

DOI: 10.1051/aas:2000316 Bibcode: 2000A&AS..141..331C

Talavera, A.; Altamore, A.; Wamsteker, W. +4 more

In this paper we document the results of the study which led to the ripple correction and absolute calibration algorithms applied to the high resolution spectra processed with the NEWSIPS software for the Final Archive of the IUE Project. In this analysis, based on a very large number of spectra, we find that both the K and alpha parameters (not o…

2000 • Astronomy and Astrophysics Supplement Series

IUE 20

VLBI observations of two single dMe stars: spatial resolution and astrometry

DOI: 10.48550/arXiv.astro-ph/9912159 Bibcode: 2000A&A...353..569P

Güdel, M.; Benz, A. O.; Conway, J. E. +1 more

We report on 3.6 cm VLA and VLBA observations of YZ CMi and AD Leo, two nearby dMe stars. We resolve YZ CMi and can fit a circular symmetrical gaussian component of FWHP of 0.98 +/-0.2 mas, corresponding to an extent of the corona above the photosphere of 1.77 x 10¹⁰ +/-8.8 x 10⁹ cm or 0.…

2000 • Astronomy and Astrophysics

Hipparcos 20

X1908+075: An X-Ray Binary with a 4.4 Day Period

DOI: 10.1086/308604 Bibcode: 2000ApJ...532.1119W

Remillard, Ronald A.; Wen, Linqing; Bradt, Hale V.

X1908+075 is an optically unidentified and highly absorbed X-ray source that appeared in early surveys such as Uhuru, OSO 7, Ariel 5, HEAO-1, and the EXOSAT Galactic Plane Survey. These surveys measured a source intensity in the range 2-12 mcrab at 2-10 keV, and the position was localized to ~0.5d. We use the Rossi X-Ray Timing Explorer (RXTE) All…

2000 • The Astrophysical Journal

Exosat 20

Oxygen freeze-in temperatures measured with SOHO/CELIAS/CTOF

DOI: 10.1029/1999JA900384 Bibcode: 2000JGR...10510527H

Bochsler, P.; Grünwaldt, H.; Hefti, S. +1 more

We use the charge time-of-flight (CTOF) mass and charge spectrometer of the charge, element, and isotope analysis system (CELIAS) on board the Solar and Heliospheric Observatory (SOHO) to determine the solar wind oxygen freeze-in temperature T₇₆ from the O⁷⁺ and O⁶⁺ abundance ratios in the period from days 92 to 22…

2000 • Journal of Geophysical Research

SOHO 20

The outer atmosphere of α Tau - III. Inhomogeneities deduced from cold CO fluorescence

DOI: 10.1046/j.1365-8711.2000.03213.x Bibcode: 2000MNRAS.313..423M

McMurry, A. D.; Jordan, C.

Ultraviolet spectra of α Tau obtained with the Goddard High Resolution Spectrograph (GHRS) on the Hubble Space Telescope show clusters of CO emission lines which are excited by the Oi (uv2) multiplet near 1304Å. Identifications of these fluorescent lines and their pumping routes are presented. The absolute intensities of the CO lines and their rat…

2000 • Monthly Notices of the Royal Astronomical Society

eHST 20

HST spectroscopy of the double QSO HS 1216+5032 AB

DOI: 10.48550/arXiv.astro-ph/0003427 Bibcode: 2000A&A...357...37L

Reimers, D.; Hagen, H. -J.; Lopez, S.

We report on Hubble Space Telescope Faint Object Spectrograph observations of the double QSO HS 1216+5032 AB (z_e(A)=1.455; z_e(B)=1.451, and angular separation theta =9.1farcs ). The spectral coverage is 910 Å to 1340 Å in the QSO rest-frame. An unusual broad-absorption-line (BAL) system is observed only in the B component: maximum outflow veloci…

2000 • Astronomy and Astrophysics

eHST 20