dc.contributor.author | Huenemoerder, David P. | |
dc.contributor.author | Schulz, Norbert S. | |
dc.contributor.author | Testa, Paola | |
dc.contributor.author | Kesich, Anthony R. | |
dc.contributor.author | Canizares, Claude R. | |
dc.date.accessioned | 2010-02-11T18:25:34Z | |
dc.date.available | 2010-02-11T18:25:34Z | |
dc.date.issued | 2009-11 | |
dc.date.submitted | 2009-08 | |
dc.identifier.issn | 0004-637X | |
dc.identifier.uri | http://hdl.handle.net/1721.1/51722 | |
dc.description.abstract | θ(1) Ori E is a young, moderate mass binary system, a rarely observed case of spectral-type G-giants of about 3 solar masses, which are still collapsing toward the main sequence, where they presumably become X-ray faint. We have obtained high-resolution X-ray spectra with Chandra and find that the system is very active and similar to coronal sources, having emission typical of magnetically confined plasma. It has a broad temperature distribution with a hot component and significant high energy continuum; narrow emission lines from H- and He-like ions, as well as a range of Fe ions, and relative luminosity, L[subscript x] /L [subscript bol] = 10(–3), at the saturation limit. Density, while poorly constrained, is consistent with the low density limits, our upper limits being ne < 10(13) cm(-3) for Mg XI and ne < 10(12) cm(-3) for Ne IX. Coronal elemental abundances are sub-solar, with Ne being the highest at about 0.4 times solar. We find a possible trend in Trapezium hot plasmas toward low relative abundances of Fe, O, and Ne, which is hard to explain in terms of the dust depletion scenarios of low-mass young stars. Variability was unusually low during our observations relative to other coronally active stars. Qualitatively, the emission is similar to post-main-sequence G-stars. Coronal structures could be compact or comparable to the dimensions of the stellar radii. From comparison to X-ray emission from similar mass stars at various evolutionary epochs, we conclude that the X-rays in θ1 Ori E are generated by a convective dynamo, present during contraction, but which will vanish during the main-sequence epoch possibly to be resurrected during post-main-sequence evolution. | en |
dc.description.sponsorship | NASA | en |
dc.language.iso | en_US | |
dc.publisher | American Astronomical Society | en |
dc.relation.isversionof | http://dx.doi.org/10.1088/0004-637X/707/2/942 | en |
dc.rights | Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. | en |
dc.source | Claude Canizares via Gail Monahan | en |
dc.title | X-RAY EMISSION AND CORONA OF THE YOUNG INTERMEDIATE-MASS BINARY theta(1) Ori E | en |
dc.type | Article | en |
dc.identifier.citation | X-Ray Emission and Corona of the Young Intermediate-Mass Binary theta(1) Ori E
David P. Huenemoerder, Norbert S. Schulz, Paola Testa, Anthony Kesich, and Claude R. Canizares 2009 ApJ 707 942-953 doi: 10.1088/0004-637X/707/2/942. (C)2009 The American Astronomical Society. | en |
dc.contributor.department | MIT Kavli Institute for Astrophysics and Space Research | en_US |
dc.contributor.approver | Canizares, Claude R. | |
dc.contributor.mitauthor | Huenemoerder, David P. | |
dc.contributor.mitauthor | Schulz, Norbert S. | |
dc.contributor.mitauthor | Kesich, Anthony R. | |
dc.contributor.mitauthor | Canizares, Claude R. | |
dc.relation.journal | Astrophysical Journal | en |
dc.eprint.version | Final published version | en |
dc.type.uri | http://purl.org/eprint/type/JournalArticle | en |
eprint.status | http://purl.org/eprint/status/PeerReviewed | en |
eprint.grantNumber | SV3-73016 | en |
dspace.orderedauthors | Huenemoerder, David P.; Schulz, Norbert S.; Testa, Paola; Kesich, Anthony; Canizares, Claude R. | en |
dc.identifier.orcid | https://orcid.org/0000-0002-5769-8441 | |
dspace.mitauthor.error | true | |
mit.license | PUBLISHER_POLICY | en |
mit.metadata.status | Complete | |