HUBBLE SPACE TELESCOPE FUV SPECTRA OF THE POST-COMMON-ENVELOPE HYADES BINARY V471 Tauri

Journal Article · Sun May 20 04:00:00 EDT 2012 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/751/1/66· OSTI ID:22037211

Sion, Edward M; Godon, Patrick ^[1]; Bond, Howard E ^[2]; Lindler, Don ^[3]; Wickramasinghe, Dayal; Ferrario, Lilia ^[4]; Dupuis, Jean ^[5]

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1. Department of Astronomy and Astrophysics, Villanova University, Villanova, PA 19085 (United States)
2. Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)
3. Sigma Space Corporation, Greenbelt, MD (United States)
4. Mathematical Sciences Institute, The Australian National University, ACT0200, Canberra (Australia)
5. Space Astronomy, Canadian Space Agency, 6767 Route de l'Aeroport Saint-Hubert, Quebec J3Y 8Y9 (Canada)

We have carried out an analysis of the Hubble Space Telescope (HST)/STIS archival spectra of the magnetic white dwarf (WD) in the Hyades eclipsing-spectroscopic, post-common-envelope binary V471 Tauri, time resolved on the orbit and on the X-ray rotational phase of the magnetic WD. An HST/STIS spectrum obtained during primary eclipse reveals a host of transition region/chromospheric emission features including N V (1238, 1242), Si IV (1393, 1402), C IV (1548, 1550), and He II (1640). The spectroscopic characteristics and emission line fluxes of the transition region/chromosphere of the very active, rapidly rotating, K2V component of V471 Tauri are compared with the emission characteristics of fast rotating K dwarfs in young open clusters. We have detected a number of absorption features associated with metals accreted onto the photosphere of the magnetic WD from which we derive radial velocities. All of the absorption features are modulated on the 555 s rotation period of the WD with maximum line strength at rotational phase 0.0 when the primary magnetic accretion region is facing the observer. The photospheric absorption features show no clear evidence of Zeeman splitting and no evidence of a correlation between their variations in strength and orbital phase. We report clear evidence of a secondary accretion pole. We derive C and Si abundances from the Si IV and C III features. All other absorption lines are either interstellar or associated with a region above the WD and/or with coronal mass ejection events illuminated as they pass in front of the WD.

• OSTI ID: 22037211
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 751; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ABSORPTION SPECTRA
ASTRONOMY
ASTROPHYSICS
CARBON
CHROMOSPHERE
CORRELATIONS
ECLIPSE
ELEMENT ABUNDANCE
ORBITS
PHOTON EMISSION
PHOTOSPHERE
RADIAL VELOCITY
SILICON
TELESCOPES
TIME RESOLUTION
ULTRAVIOLET SPECTRA
WHITE DWARF STARS
ZEEMAN EFFECT