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Related papers: Mid-Cycle Changes in Eta Carinae

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Eta Carinae's inner ejecta are dominated observationally by the bright Weigelt blobs and their famously rich spectra of nebular emission and absorption lines. They are dense (n_e ~ 10^7 to 10^8 cm^-3), warm (T_e ~ 6000 to 7000 K) and slow…

Astrophysics of Galaxies · Physics 2015-06-12 Fred Hamann

Eta Carinae is the nearest example of a supermassive, superluminous, unstable star. Mass loss from the system is critical in shaping its circumstellar medium and in determining its ultimate fate. Eta Car currently loses mass via a dense,…

We present a three-dimensional (3-D) dynamical model for the broad [Fe III] emission observed in Eta Carinae using the Hubble Space Telescope/Space Telescope Imaging Spectrograph (HST/STIS). This model is based on full 3-D Smoothed Particle…

Solar and Stellar Astrophysics · Physics 2015-06-03 Thomas I. Madura , Theodore R. Gull , Stanley P. Owocki , Jose H. Groh , Atsuo T. Okazaki , Christopher M. P. Russell

We present an updated and improved description of the light curve behaviour of T Ursae Minoris, which is a Mira star with the strongest period change (the present rate is an amazing -3.8+/-0.4 days/year corresponding to a relative decrease…

Astrophysics · Physics 2009-03-09 K. Szatmary , L. L. Kiss , Zs. Bebesi

The subject of micro-variability among Mira stars has received increased attention since DeLaverny et al. (1998) reported short-term brightness variations in 15 percent of the 250 Mira or Long Period Variable stars surveyed using the…

Astrophysics · Physics 2007-05-23 D. E. Mais , D. Richards , R. E. Stencel

High-resolution spectra of [Fe II] 16435 around eta Carinae provide powerful diagnostics of the geometry and kinematics of the ``Little Homunculus'' (LH) growing inside the larger Homunculus nebula. The LH expansion is not perfectly…

Astrophysics · Physics 2009-11-10 Nathan Smith

We present critical, long-wavelength observations of Eta Carinae in the submillimetre using SCUBA on the JCMT at 850 and 450 um to confirm the presence of a large mass of warm dust around the central star. We fit a two-component blackbody…

Astrophysics · Physics 2009-11-11 H. L. Gomez , L. Dunne , S. A. Eales , M. G. Edmunds

Single-dish sub-millimeter observations have recently revealed the existence of a substantial, chemically peculiar, molecular gas component located in the innermost circumstellar environment of the very massive luminous blue variable star…

Solar and Stellar Astrophysics · Physics 2016-12-14 L. Loinard , T. Kaminski , P. Serra , K. Menten , L. Zapata , L. Rodriguez

\eta\ Car is the only colliding-wind binary for which high-energy \gamma\ rays are detected. Although the physical conditions in the shock region change on timescales of hours to days, the variability seen at GeV energies is weak and on…

High Energy Astrophysical Phenomena · Physics 2015-06-23 S. Ohm , V. Zabalza , J. A. Hinton , E. R. Parkin

We modeled the HeII 4686 line profiles observed in the eta Carinae binary system close to the 2003.5 spectroscopic event, assuming that they were formed in the shocked gas that flows at both sides of the contact surface formed by wind-wind…

Astrophysics · Physics 2008-11-26 Z. Abraham , D. Falceta-Goncalves

The binary eta Carinae is the closest example of a very massive star, which may have formed through a merger during its Great Eruption in the mid-nineteenth century. We aimed to confirm and improve the kinematics using a spectroscopic data…

Eta Car may be the most massive and luminous star in the Galaxy and is suspected to be a massive, colliding wind binary system. The CHANDRA X-ray observatory has obtained a calibrated, high-resolution X-ray spectrum of the star…

We present more than 1000-day long photometry of EY Draconis in BV(RI)C passbands. The changes in the light curve are caused by the spottedness of the rotating surface. Modelling of the spotted surface shows that there are two large active…

Solar and Stellar Astrophysics · Physics 2013-03-08 K. Vida , K. Oláh , Zs. Kővári , J. Jurcsik , Á. Sódor , M. Váradi , B. Belucz , I. Dékány , Zs. Hurta , I. Nagy , K. Posztobányi

We report the first detection of ammonia in the Homunculus nebula around eta Carinae, which is also the first detection of emission from a polyatomic molecule in this or any other luminous blue variable (LBV) nebula. Observations of the NH3…

Astrophysics · Physics 2010-11-11 Nathan Smith , Kate J. Brooks , Baerbel S. Koribalski , John Bally

Using the Hopkins Ultraviolet Telescope (HUT), we have obtained 850-1850 angstrom spectra of the magnetic cataclysmic variable star AM Her in the high state. These observations provide high time resolution spectra of AM Her in the FUV and…

Astrophysics · Physics 2009-10-31 Bradford W. Greeley , William P. Blair , Knox S. Long , John C. Raymond

This work presents the first integral field spectroscopy of the Homunculus nebula around Eta Carinae in the near-infrared spectral region (J band). We confirmed the presence of a hole on the polar region of each lobe, as indicated by…

Astrophysics · Physics 2009-11-13 M. Teodoro , A. Damineli , R. G. Sharp , J. H. Groh , C. L. Barbosa

Far-infrared Herschel PACS imaging and spectroscopic observations of the nebula around the luminous blue variable (LBV) star AG Car have been obtained along with optical imaging in the Halpha+[NII] filter. In the infrared light, the nebula…

Solar and Stellar Astrophysics · Physics 2015-06-17 C. Vamvatira-Nakou , D. Hutsemekers , P. Royer , N. L. J. Cox , Y. Naze , G. Rauw , C. Waelkens , M. A. T. Groenewegen

I examine some aspects of the interaction between the massive star Eta Carinae and its companion, in particular during the eclipse-like event, known as the spectroscopic event or the shell event. The spectroscopic event is thought to occur…

Astrophysics · Physics 2009-11-10 Noam Soker

We have analyzed Beta Pictoris photometric measurements obtained from La Silla by the Geneva Observatory from 1975 to 1992. These data show evidence of variations in the brightness of the star, with no color dependency. Here, we demonstrate…

Astrophysics · Physics 2011-05-23 A. Lecavelier des Etangs , M. Deleuil , A. Vidal-Madjar et al

Advances in understanding of the white light faculae measured at the Royal Greenwich Observatory from 1874 to 1976 suggest that they offer a more direct measure of solar brightening by small diameter photospheric magnetic flux tubes than do…

Solar and Stellar Astrophysics · Physics 2015-12-09 Peter Foukal
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