HD 139319
HD 139319 is a ternary system composed of the binary Algol variable star known as TW Draconis, and a main-sequence companion star at a separation of 3 arcseconds. The system lies in the constellation of Draco about 540 light years away.
System
The primary star is an eclipsing, semi-detached binary, the brighter component of which is a pulsating star of Delta Scuti type. Its pulsation frequency is 17.99 cycles per day. Mass transfer between stars is ongoing in the system with a transfer rate of 6.8×10M☉/year. The 2.8 day period of the Algol binary is cyclically variable with a period 116.04 years, possibly due to gravitational influence of the distant companion HD 139319B. Another three stars in the system are suspected.
References
- ^ "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. Retrieved 8 December 2021.
- ^ "TW Dra". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2021-12-13.
- ^ Kim, S.-L.; Lee, J. W.; Kwon, S.-G.; Youn, J.-H.; Mkrtichian, D. E.; Kim, C. (2003), "Search for A–F Spectral type pulsating components in Algol-type eclipsing binary systems", Astronomy & Astrophysics, 405: 231–236, Bibcode:2003A&A...405..231K, doi:10.1051/0004-6361:20030630
- ^ Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
- ^ Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
- ^ Liao, Wen-Ping; Qian, Sheng-Bang; Zejda, Miloslav; Zhu, Li-Ying; Li, Lin-Jia (2016), "Lunar-based Ultraviolet Telescope study of the well-known Algol-type binary TW Dra", Research in Astronomy and Astrophysics, 16 (6): 009, Bibcode:2016RAA....16...94L, doi:10.1088/1674-4527/16/6/094, S2CID 124656327
- ^ Bozic, H.; Nemravova, J.; Harmanec, P. (2013), "Standard UBV photometry and improved physical properties of TW Dra", Information Bulletin on Variable Stars, 6086: 1, Bibcode:2013IBVS.6086....1B
- ^ Norton, A. J.; Lohr, M. E.; Smalley, B.; Wheatley, P. J.; West, R. G. (2016), "SuperWASP discovery and SALT confirmation of a semi-detached eclipsing binary that contains aδScuti star", Astronomy & Astrophysics, 587: A54, arXiv:1601.03198, Bibcode:2016A&A...587A..54N, doi:10.1051/0004-6361/201526881, S2CID 10625309
