تقرير
Evidence for an FU Orionis-like Outburst from a Classical T Tauri Star
| العنوان: | Evidence for an FU Orionis-like Outburst from a Classical T Tauri Star |
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| المؤلفون: | Miller, Adam A., Hillenbrand, Lynne A., Covey, Kevin R., Poznanski, Dovi, Silverman, Jeffrey M., Kleiser, Io K. W., Rojas-Ayala, Barbara, Muirhead, Philip S., Cenko, S. Bradley, Bloom, Joshua S., Kasliwal, Mansi M., Filippenko, Alexei V., Law, Nicholas M., Ofek, Eran O., Dekany, Richard G., Rahmer, Gustavo, Hale, David, Smith, Roger, Quimby, Robert M., Nugent, Peter, Jacobsen, Janet, Zolkower, Jeff, Velur, Viswa, Walters, Richard, Henning, John, Bui, Khanh, McKenna, Dan, Kulkarni, Shrinivas R., Klein, Christopher R. |
| سنة النشر: | 2010 |
| المجموعة: | Astrophysics |
| مصطلحات موضوعية: | Astrophysics - Solar and Stellar Astrophysics, Astrophysics - Astrophysics of Galaxies |
| الوصف: | We present pre- and post-outburst observations of the new FU Orionis-like young stellar object PTF 10qpf (also known as LkHa 188-G4 and HBC 722). Prior to this outburst, LkHa 188-G4 was classified as a classical T Tauri star on the basis of its optical emission-line spectrum superposed on a K8-type photosphere, and its photometric variability. The mid-infrared spectral index of LkHa 188-G4 indicates a Class II-type object. LkHa 188-G4 exhibited a steady rise by ~1 mag over ~11 months starting in Aug. 2009, before a subsequent more abrupt rise of > 3 mag on a time scale of ~2 months. Observations taken during the eruption exhibit the defining characteristics of FU Orionis variables: (i) an increase in brightness by > 4 mag, (ii) a bright optical/near-infrared reflection nebula appeared, (iii) optical spectra are consistent with a G supergiant and dominated by absorption lines, the only exception being Halpha which is characterized by a P Cygni profile, (iv) near-infrared spectra resemble those of late K--M giants/supergiants with enhanced absorption seen in the molecular bands of CO and H_2O, and (v) outflow signatures in H and He are seen in the form of blueshifted absorption profiles. LkHa 188-G4 is the first member of the FU Orionis-like class with a well-sampled optical to mid-infrared spectral energy distribution in the pre-outburst phase. The association of the PTF 10qpf outburst with the previously identified classical T Tauri star LkHa 188-G4 (HBC 722) provides strong evidence that FU Orionis-like eruptions represent periods of enhanced disk accretion and outflow, likely triggered by instabilities in the disk. The early identification of PTF 10qpf as an FU Orionis-like variable will enable detailed photometric and spectroscopic observations during its post-outburst evolution for comparison with other known outbursting objects. Comment: 14 pages, 11 figures, ApJ accepted |
| نوع الوثيقة: | Working Paper |
| DOI: | 10.1088/0004-637X/730/2/80 |
| URL الوصول: | http://arxiv.org/abs/1011.2063 |
| رقم الأكسشن: | edsarx.1011.2063 |
| قاعدة البيانات: | arXiv |
| DOI: | 10.1088/0004-637X/730/2/80 |
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