THE H{alpha} VARIATIONS OF {eta} CARINAE DURING THE 2009.0 SPECTROSCOPIC EVENT

Journal Article · Thu Apr 15 04:00:00 EDT 2010 · Astronomical Journal (New York, N.Y. Online)

DOI:https://doi.org/10.1088/0004-6256/139/4/1534; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA)· OSTI ID:21301186

Richardson, N D; Gies, D R; Henry, T J ^[1]; Fernandez-Lajus, E ^[2]

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1. Center for High Angular Resolution Astronomy, Department of Physics and Astronomy, Georgia State University, P.O. Box 4106, Atlanta, GA 30302-4106 (United States)
2. Facultad de Ciencias Astronomicas y Geofisicas, Universidad Nacional de La Plata, Observatorio Astronomico, Paseo del Bosque s/n, La Plata, BA, B1900FWA (Argentina)

We report on H{alpha} spectroscopy of the 2009.0 spectroscopic event of {eta} Carinae collected via SMARTS observations using the Cerro Tololo Interamerican Observatory 1.5 m telescope and echelle spectrograph. Our observations were made almost every night over a two-month interval around the predicted minimum of {eta} Car. We observed a significant fading of the line emission that reached a minimum 7 days after the X-ray minimum. About 17 days prior to the H{alpha} flux minimum, the H{alpha} profile exhibited the emergence of a broad, P Cygni type, absorption component (near a Doppler shift of -500 km s{sup -1}) and a narrow absorption component (near -144 km s{sup -1} and probably associated with intervening gas from the Little Homunculus Nebula). All these features were observed during the last event in 2003.5 and are probably related to the close periastron passage of the companion. We argue that these variations are consistent with qualitative expectations about changes in the primary star's stellar wind that result from the wind-wind collision with a massive binary companion and from atmospheric eclipses of the companion.

• OSTI ID: 21301186
• Journal Information: Astronomical Journal (New York, N.Y. Online), Journal Name: Astronomical Journal (New York, N.Y. Online) Journal Issue: 4 Vol. 139; ISSN 1538-3881
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
99 GENERAL AND MISCELLANEOUS
ABSORPTION
DOPPLER EFFECT
ECLIPSE
NEBULAE
SPECTROSCOPY
STARS
STELLAR WINDS
TELESCOPES
X RADIATION