EPSILON AURIGAE: AN IMPROVED SPECTROSCOPIC ORBITAL SOLUTION
A rare eclipse of the mysterious object ε Aurigae will occur in 2009-2011. We report an updated single-lined spectroscopic solution for the orbit of the primary star based on 20 years of monitoring at the CfA, combined with historical velocity observations dating back to 1897. There are 518 new CfA...
| Main Authors: | , , , , , , |
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| Other Authors: | |
| Format: | Article |
| Language: | en_US |
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IOP Publishing
2015
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| Online Access: | http://hdl.handle.net/1721.1/93146 |
| _version_ | 1826193348696735744 |
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| author | Stefanik, Robert P. Torres, Guillermo Lovegrove, Justin Pera, Vivian E. Latham, David W. Zajac, Joseph Mazeh, Tsevi |
| author2 | Lincoln Laboratory |
| author_facet | Lincoln Laboratory Stefanik, Robert P. Torres, Guillermo Lovegrove, Justin Pera, Vivian E. Latham, David W. Zajac, Joseph Mazeh, Tsevi |
| author_sort | Stefanik, Robert P. |
| collection | MIT |
| description | A rare eclipse of the mysterious object ε Aurigae will occur in 2009-2011. We report an updated single-lined spectroscopic solution for the orbit of the primary star based on 20 years of monitoring at the CfA, combined with historical velocity observations dating back to 1897. There are 518 new CfA observations obtained between 1989 and 2009. Two solutions are presented. One uses the velocities outside the eclipse phases together with mid-times of previous eclipses, from photometry dating back to 1842, which provide the strongest constraint on the ephemeris. This yields a period of 9896.0 ± 1.6 days (27.0938 ± 0.0044 years) with a velocity semi-amplitude of 13.84 ± 0.23 km s[superscript –1] and an eccentricity of 0.227 ± 0.011. The middle of the current ongoing eclipse predicted by this combined fit is JD 2,455,413.8 ± 4.8, corresponding to 2010 August 5. If we use only the radial velocities, we find that the predicted middle of the current eclipse is nine months earlier. This would imply that the gravitating companion is not the same as the eclipsing object. Alternatively, the purely spectroscopic solution may be biased by perturbations in the velocities due to the short-period oscillations of the supergiant. |
| first_indexed | 2024-09-23T09:37:59Z |
| format | Article |
| id | mit-1721.1/93146 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T09:37:59Z |
| publishDate | 2015 |
| publisher | IOP Publishing |
| record_format | dspace |
| spelling | mit-1721.1/931462022-09-26T12:44:56Z EPSILON AURIGAE: AN IMPROVED SPECTROSCOPIC ORBITAL SOLUTION Stefanik, Robert P. Torres, Guillermo Lovegrove, Justin Pera, Vivian E. Latham, David W. Zajac, Joseph Mazeh, Tsevi Lincoln Laboratory Pera, Vivian E. A rare eclipse of the mysterious object ε Aurigae will occur in 2009-2011. We report an updated single-lined spectroscopic solution for the orbit of the primary star based on 20 years of monitoring at the CfA, combined with historical velocity observations dating back to 1897. There are 518 new CfA observations obtained between 1989 and 2009. Two solutions are presented. One uses the velocities outside the eclipse phases together with mid-times of previous eclipses, from photometry dating back to 1842, which provide the strongest constraint on the ephemeris. This yields a period of 9896.0 ± 1.6 days (27.0938 ± 0.0044 years) with a velocity semi-amplitude of 13.84 ± 0.23 km s[superscript –1] and an eccentricity of 0.227 ± 0.011. The middle of the current ongoing eclipse predicted by this combined fit is JD 2,455,413.8 ± 4.8, corresponding to 2010 August 5. If we use only the radial velocities, we find that the predicted middle of the current eclipse is nine months earlier. This would imply that the gravitating companion is not the same as the eclipsing object. Alternatively, the purely spectroscopic solution may be biased by perturbations in the velocities due to the short-period oscillations of the supergiant. 2015-01-22T18:59:43Z 2015-01-22T18:59:43Z 2010-02 2009-11 Article http://purl.org/eprint/type/JournalArticle 0004-6256 1538-3881 http://hdl.handle.net/1721.1/93146 Stefanik, Robert P., Guillermo Torres, Justin Lovegrove, Vivian E. Pera, David W. Latham, Joseph Zajac, and Tsevi Mazeh. “EPSILON AURIGAE: AN IMPROVED SPECTROSCOPIC ORBITAL SOLUTION.” The Astronomical Journal 139, no. 3 (February 11, 2010): 1254–1260. doi:10.1088/0004-6256/139/3/1254. en_US http://dx.doi.org/10.1088/0004-6256/139/3/1254 The Astronomical Journal 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. application/pdf IOP Publishing American Astronomical Society |
| spellingShingle | Stefanik, Robert P. Torres, Guillermo Lovegrove, Justin Pera, Vivian E. Latham, David W. Zajac, Joseph Mazeh, Tsevi EPSILON AURIGAE: AN IMPROVED SPECTROSCOPIC ORBITAL SOLUTION |
| title | EPSILON AURIGAE: AN IMPROVED SPECTROSCOPIC ORBITAL SOLUTION |
| title_full | EPSILON AURIGAE: AN IMPROVED SPECTROSCOPIC ORBITAL SOLUTION |
| title_fullStr | EPSILON AURIGAE: AN IMPROVED SPECTROSCOPIC ORBITAL SOLUTION |
| title_full_unstemmed | EPSILON AURIGAE: AN IMPROVED SPECTROSCOPIC ORBITAL SOLUTION |
| title_short | EPSILON AURIGAE: AN IMPROVED SPECTROSCOPIC ORBITAL SOLUTION |
| title_sort | epsilon aurigae an improved spectroscopic orbital solution |
| url | http://hdl.handle.net/1721.1/93146 |
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