BP Tauri

Summary

BP Tauri is a young T Tauri star in the constellation of Taurus about 416 light years away, belonging to the Taurus Molecular Cloud.

BP Tauri

A light curve for BP Tauri, plotted from TESS data[1]
Observation data
Epoch J2000      Equinox J2000
Constellation Taurus
Right ascension 04h 19m 15.8343s[2]
Declination +29° 06′ 26.9295″[2]
Apparent magnitude (V) 12.12
Characteristics
Evolutionary stage pre-main-sequence star
Spectral type K5
Apparent magnitude (G) 11.460[3]
Variable type T Tau
Astrometry
Radial velocity (Rv)15.76±0.13 km/s
Proper motion (μ) RA: 8.889[3] mas/yr
Dec.: -26.011[3] mas/yr
Parallax (π)7.8494 ± 0.0362 mas[3]
Distance416 ± 2 ly
(127.4 ± 0.6 pc)
Details
Mass1.24+0.25
−0.32
[4] M
Radius2.0[5] R
Luminosity0.93[5] L
Surface gravity (log g)4.32±0.14[6] cgs
Temperature3640+94
−92
[6] K
Rotational velocity (v sin i)11.4+0.25
−0.55
[6] km/s
Age6±4[4] Myr
Other designations
Gaia DR2 164832740220756608, HD 281934, HIP 20160, TYC 1827-554-1, GSC 01827-00554, 2MASS J04191583+2906269
Database references
SIMBADdata

Properties edit

BP Tauri is still accreting mass at the low rate of 9×10−10 M and 1.6×10−7 M/year,[7] as evidenced by X-rays produced by infalling matter,[8] and may be still in the process of spin-up.[9] Its chromospheric magnetic fields are rather strong at 2.5+0.15
−0.16
kilogauss,[6] and contains strong non-dipole components.[10] The star is producing 40% of its luminosity via the energy released by accretion.[5]

Suspected companions edit

There were two suspected stellar companions to BP Tauri on projected separations 3.00 and 5.45 arcseconds.[11] These were proven to be a background stars not related to BP Tauri with Gaia data though.[12][13]

Protoplanetary system edit

The star is surrounded by a protoplanetary disk. The disk is strongly depleted in carbon and carbon monoxide.[14]

The planetary system
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
protoplanetary disk 0–120[15] AU 30[14]°

Variability edit

BP Tauri varies in brightness, producing a strong flares due to unsteady accretion[5] held by stellar magnetic field. The lightcurve period is variable from 6.1 to 7.6 days, and quiescent periods without variability are also known.[16]

References edit

  1. ^ "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. Retrieved 8 December 2021.
  2. ^ a b "V* BP Tau". SIMBAD. Centre de données astronomiques de Strasbourg.
  3. ^ a b c d 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.
  4. ^ a b Simon, M.; Dutrey, A.; Guilloteau, S. (2000), "Dynamical Masses of T Tauri Stars and Calibration of Pre–Main-Sequence Evolution", The Astrophysical Journal, 545 (2): 1034–1043, arXiv:astro-ph/0008370, Bibcode:2000ApJ...545.1034S, doi:10.1086/317838, S2CID 18064837
  5. ^ a b c d Errico, L.; Lamzin, S. A.; Vittone, A. A. (2001), "UV spectra of T Tauri stars from the HST and IUE satellites: BP Tau", Astronomy & Astrophysics, 377 (2): 557–565, Bibcode:2001A&A...377..557E, doi:10.1051/0004-6361:20011108
  6. ^ a b c d Flores, C.; Connelley, M. S.; Reipurth, B.; Boogert, A. (2019), "Measuring the Magnetic Field of Young Stars Using iSHELL Observations: BP Tau and V347 Aur", The Astrophysical Journal, 882 (2): 75, arXiv:1908.08583, Bibcode:2019ApJ...882...75F, doi:10.3847/1538-4357/ab35d4, S2CID 201645503
  7. ^ Long, M.; Romanova, M. M.; Kulkarni, A. K.; Donati, J.-F. (2010), "Global 3D simulations of disc accretion on to the classical T Tauri star BP Tauri", Monthly Notices of the Royal Astronomical Society, 413 (2): 1061–1071, arXiv:1009.3300, doi:10.1111/j.1365-2966.2010.18193.x, S2CID 55134816
  8. ^ Schmitt, J. H. M. M.; Robrade, J.; Ness, J.-U.; Favata, F.; Stelzer, B. (2005), "X-rays from accretion shocks in T Tauri stars: The case of BP Tau", Astronomy & Astrophysics, 432 (2): L35–L38, arXiv:astro-ph/0503144, Bibcode:2005A&A...432L..35S, doi:10.1051/0004-6361:200500014, S2CID 2457531
  9. ^ Ireland, Lewis G.; Zanni, Claudio; Matt, Sean P.; Pantolmos, George (2020), "Magnetic Braking of Accreting T Tauri Stars: Effects of Mass Accretion Rate, Rotation, and Dipolar Field Strength", The Astrophysical Journal, 906: 4, arXiv:2011.01087, doi:10.3847/1538-4357/abc828, S2CID 226236865
  10. ^ Long, Min; Romanova, Marina M.; Lamb, Frederick K. (2009), "Accretion onto stars with octupole magnetic fields: Matter flow, hot spots and phase shifts", New Astronomy, 17 (2): 232–245, arXiv:0911.5455, Bibcode:2012NewA...17..232L, doi:10.1016/j.newast.2011.08.001, S2CID 119113916
  11. ^ Itoh, Yoichi; Tamura, Motohide; Hayashi, Masahiko; Oasa, Yumiko; Hayashi, Saeko S.; Fukagawa, Misato; Kudo, Tomoyuki; Mayama, Satoshi; Ishii, Miki; Pyo, Tae-Soo; Yamashita, Takuya; Morino, Junichi (2008). "Near-Infrared Spectroscopy of Faint Companions around Young Stellar Objects Associated with the Taurus Molecular Cloud". Publications of the Astronomical Society of Japan. 60 (2): 209–218. Bibcode:2008PASJ...60..209I. doi:10.1093/pasj/60.2.209. hdl:20.500.14094/90001427.
  12. ^ 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.
  13. ^ 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.
  14. ^ a b Kama, M.; Bruderer, S.; Carney, M.; Hogerheijde, M.; Van Dishoeck, E. F.; Fedele, D.; Baryshev, A.; Boland, W.; Güsten, R.; Aikutalp, A.; Choi, Y.; Endo, A.; Frieswijk, W.; Karska, A.; Klaassen, P.; Koumpia, E.; Kristensen, L.; Leurini, S.; Nagy, Z.; Perez Beaupuits, J. -P.; Risacher, C.; Van Der Marel, N.; Van Kempen, T. A.; Van Weeren, R. J.; Wyrowski, F.; Yıldız, U. A. (2016). "Observations and modelling of CO and [C I] in protoplanetary disks. First detections of [C I] and constraints on the carbon abundance". Astronomy and Astrophysics. 588: 588. arXiv:1601.01449. Bibcode:2016A&A...588A.108K. doi:10.1051/0004-6361/201526791. S2CID 53941444.
  15. ^ Dutrey, A.; Guilloteau, S.; Simon, M. (2003). "The BP Tau disk: A missing link between Class II and III objects?". Astronomy and Astrophysics. 402 (3): 1003. Bibcode:2003A&A...402.1003D. doi:10.1051/0004-6361:20030317.
  16. ^ Simon, Theodore; Vrba, Frederick J.; Herbst, William (1990). "The Ultraviolet and Visible Light Variability of BP Tauri: Possible Clues for the Origin of T Tauri Star Activity". The Astronomical Journal. 100: 1957. Bibcode:1990AJ....100.1957S. doi:10.1086/115651.