FK COMAE BERENICES, KING OF SPIN: THE COCOA-PUFS PROJECT
COCOA-PUFS is an energy-diverse, time-domain study of the ultra-fast spinning, heavily spotted, yellow giant FK Comae Berenices (FK Com: HD117555; G4 III). This single star is thought to be a recent binary merger, and is exceptionally active by measure of its intense ultraviolet (UV) and X-ray emiss...
| Main Authors: | , , , , , , , , , , |
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| Formato: | Artigo |
| Idioma: | en_US |
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IOP Publishing
2017
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| Acesso em linha: | http://hdl.handle.net/1721.1/108368 |
| _version_ | 1826207253270626304 |
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| author | Ayres, Thomas R. Kashyap, V. Saar, S. Korhonen, H. Drake, J. J. Cohen, O. Garraffo, C. Granzer, T. Strassmeier, K. Testa, Paola Huenemoerder, David P. |
| author2 | MIT Kavli Institute for Astrophysics and Space Research |
| author_facet | MIT Kavli Institute for Astrophysics and Space Research Ayres, Thomas R. Kashyap, V. Saar, S. Korhonen, H. Drake, J. J. Cohen, O. Garraffo, C. Granzer, T. Strassmeier, K. Testa, Paola Huenemoerder, David P. |
| author_sort | Ayres, Thomas R. |
| collection | MIT |
| description | COCOA-PUFS is an energy-diverse, time-domain study of the ultra-fast spinning, heavily spotted, yellow giant FK Comae Berenices (FK Com: HD117555; G4 III). This single star is thought to be a recent binary merger, and is exceptionally active by measure of its intense ultraviolet (UV) and X-ray emissions, and proclivity to flare. COCOA-PUFS was carried out with the Hubble Space Telescope in the UV (1200–3000 Å), using mainly its high-performance Cosmic Origins Spectrograph, but also high precision Space Telescope Imaging Spectrograph; Chandra X-ray Observatory in the soft X-rays (0.5–10 keV), utilizing its High-Energy Transmission Grating Spectrometer; together with supporting photometry and spectropolarimetry in the visible from the ground. This is an introductory report on the project. FK Com displayed variability on a wide range of timescales over all wavelengths during the week-long main campaign, including a large X-ray flare; "super-rotational broadening" of the far-ultraviolet "hot lines" (e.g., Si iv 1393 Å; 8 × 10[superscript 4] K) together with chromospheric Mg ii 2800 Å and C ii 1335 Å (1–3 × 10[superscript 4] K); large Doppler swings suggestive of bright regions alternately on advancing and retreating limbs of the star; and substantial redshifts of the epoch-average emission profiles. These behaviors paint a picture of a highly extended, dynamic, hot (~10 MK) coronal magnetosphere around the star, threaded by cooler structures perhaps analogous to solar prominences and replenished continually by surface activity and flares. Suppression of angular momentum loss by the confining magnetosphere could temporarily postpone the inevitable stellar spindown, thereby lengthening this highly volatile stage of coronal evolution. |
| first_indexed | 2024-09-23T13:46:44Z |
| format | Article |
| id | mit-1721.1/108368 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T13:46:44Z |
| publishDate | 2017 |
| publisher | IOP Publishing |
| record_format | dspace |
| spelling | mit-1721.1/1083682022-09-28T16:07:01Z FK COMAE BERENICES, KING OF SPIN: THE COCOA-PUFS PROJECT Ayres, Thomas R. Kashyap, V. Saar, S. Korhonen, H. Drake, J. J. Cohen, O. Garraffo, C. Granzer, T. Strassmeier, K. Testa, Paola Huenemoerder, David P. MIT Kavli Institute for Astrophysics and Space Research Huenemoerder, David P Testa, Paola COCOA-PUFS is an energy-diverse, time-domain study of the ultra-fast spinning, heavily spotted, yellow giant FK Comae Berenices (FK Com: HD117555; G4 III). This single star is thought to be a recent binary merger, and is exceptionally active by measure of its intense ultraviolet (UV) and X-ray emissions, and proclivity to flare. COCOA-PUFS was carried out with the Hubble Space Telescope in the UV (1200–3000 Å), using mainly its high-performance Cosmic Origins Spectrograph, but also high precision Space Telescope Imaging Spectrograph; Chandra X-ray Observatory in the soft X-rays (0.5–10 keV), utilizing its High-Energy Transmission Grating Spectrometer; together with supporting photometry and spectropolarimetry in the visible from the ground. This is an introductory report on the project. FK Com displayed variability on a wide range of timescales over all wavelengths during the week-long main campaign, including a large X-ray flare; "super-rotational broadening" of the far-ultraviolet "hot lines" (e.g., Si iv 1393 Å; 8 × 10[superscript 4] K) together with chromospheric Mg ii 2800 Å and C ii 1335 Å (1–3 × 10[superscript 4] K); large Doppler swings suggestive of bright regions alternately on advancing and retreating limbs of the star; and substantial redshifts of the epoch-average emission profiles. These behaviors paint a picture of a highly extended, dynamic, hot (~10 MK) coronal magnetosphere around the star, threaded by cooler structures perhaps analogous to solar prominences and replenished continually by surface activity and flares. Suppression of angular momentum loss by the confining magnetosphere could temporarily postpone the inevitable stellar spindown, thereby lengthening this highly volatile stage of coronal evolution. Space Telescope Science Institute (U.S.) (grant GO-12279) Space Telescope Science Institute (U.S.) (grant GO-12376) Space Telescope Science Institute (U.S.) (grant GO-13938) Space Telescope Science Institute (U.S.) (grant GO1- 12021X) Space Telescope Science Institute (U.S.) (grant GO1-12021X) United States. National Aeronautics and Space Administration (SAO contract SV3-73016 to MIT) 2017-04-21T21:32:21Z 2017-04-21T21:32:21Z 2016-03 2015-10 Article http://purl.org/eprint/type/JournalArticle 1538-4365 0067-0049 http://hdl.handle.net/1721.1/108368 Ayres, Thomas R., V. Kashyap, S. Saar, D. Huenemoerder, H. Korhonen, J. J. Drake, P. Testa, et al. “FK COMAE BERENICES, KING OF SPIN: THE COCOA-PUFS PROJECT.” The Astrophysical Journal Supplement Series 223, no. 1 (March 17, 2016): 5. © 2016 The American Astronomical Society en_US http://dx.doi.org/10.3847/0067-0049/223/1/5 Astrophysical Journal. Supplement Series 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 IOP Publishing |
| spellingShingle | Ayres, Thomas R. Kashyap, V. Saar, S. Korhonen, H. Drake, J. J. Cohen, O. Garraffo, C. Granzer, T. Strassmeier, K. Testa, Paola Huenemoerder, David P. FK COMAE BERENICES, KING OF SPIN: THE COCOA-PUFS PROJECT |
| title | FK COMAE BERENICES, KING OF SPIN: THE COCOA-PUFS PROJECT |
| title_full | FK COMAE BERENICES, KING OF SPIN: THE COCOA-PUFS PROJECT |
| title_fullStr | FK COMAE BERENICES, KING OF SPIN: THE COCOA-PUFS PROJECT |
| title_full_unstemmed | FK COMAE BERENICES, KING OF SPIN: THE COCOA-PUFS PROJECT |
| title_short | FK COMAE BERENICES, KING OF SPIN: THE COCOA-PUFS PROJECT |
| title_sort | fk comae berenices king of spin the cocoa pufs project |
| url | http://hdl.handle.net/1721.1/108368 |
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