New results of magnetic field measurements for BP Tau

Chuntonov, G. A.; Smirnov, D. A.; Ламзин, С. А.

doi:10.1134/s1063773707010057

Cited by 9 publications

(10 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…And, finally, it is worth drawing a parallel with the young star BP Tau, whose magnetic field has been measured at the SAO (Special Astrophysical Observatory); the field was found not to be stationary and its structure may undergo readjustments over a time on the order of a few hours [31]. Short-term variability in the magnetic field may be caused by nonstationary small-scale fields of active regions on the star's surface.…”

Section: Conclusion and Discussionmentioning

confidence: 98%

Analysis of a 30-year series of photoelectric observations of RY Tauri. I. Search for possible periodicities

Zajtseva

2010

Astrophysics

View full text Add to dashboard Cite

Searches for periodic variations in the brightness of RYTauri over various time intervals are conducted on the basis of photoelectric observations made by the author at the Crimean Station of the Shternberg State Astronomical Institute (GAISh) from 1965 through 2000 and of data published by others. The total duration of the series of observations is 12500 days. The existence of a long cycle lasting about 2000 days is confirmed. Short periods owing to rotational modulation of the brightness are not always present. During a time when the brightness of the star was increasing in 1966, a period of 7.5 days showed up. The detection of fluctuations which might be identified with rotational modulation evidently depends on the star's level of brightness. In 1993 and 1996, respectively, periods of 20.0 and 29.4 days were discovered which are most likely caused by inhomogeneities in the circumstellar disk.

show abstract

Section: Conclusion and Discussionmentioning

confidence: 98%

Analysis of a 30-year series of photoelectric observations of RY Tauri. I. Search for possible periodicities

Zajtseva

2010

Astrophysics

View full text Add to dashboard Cite

show abstract

“…Several authors have reported the detection of magnetic fields on BP Tau (Johns‐Krull, Valenti & Koresko 1999b; Johns‐Krull 2007; Donati et al 2008a) with a strong circular polarization signal commonly detected in the accretion‐related He i 5876Å emission line (Johns‐Krull et al 1999a; Valenti & Johns‐Krull 2004; Symington et al 2005; Chuntonov, Smirnov & Lamzin 2007), as well as in other accretion‐related emission lines (e.g. the Ca ii infrared triplet and He i 6678 Å; Donati et al 2008a).…”

Section: The Stars Bp Tau and V2129 Ophmentioning

confidence: 99%

“…the Ca ii infrared triplet and He i 6678 Å; Donati et al 2008a). Despite the concerns of Chuntonov et al (2007), 1 Donati et al (2008a) have presented clear evidence that the Zeeman signatures in both photospheric‐ and accretion‐related lines are dominated by rotational modulation, having monitored BP Tau for a complete rotation cycle at two different epochs. Interestingly, the large‐scale structure of BP Tau's field was found to be similar despite the observing runs being separated by almost 11 months.…”

Section: The Stars Bp Tau and V2129 Ophmentioning

confidence: 99%

The non-dipolar magnetic fields of accreting T Tauri stars

Gregory

Donati

Jardine

2008

Monthly Notices of the Royal Astronomical Society

113

View full text Add to dashboard Cite

Models of magnetospheric accretion on to classical T Tauri stars often assume that stellar magnetic fields are simple dipoles. Recently published surface magnetograms of BP Tau and V2129 Oph have shown, however, that their fields are more complex. The magnetic field of V2129 Oph was found to be predominantly octupolar. For BP Tau the magnetic energy was shared mainly between the dipole and octupole field components, with the dipole component being almost four times as strong as that of V2129 Oph. From the published surface maps of the photospheric magnetic fields we extrapolate the coronal fields of both stars, and compare the resulting field structures with that of a dipole. We consider different models where the disc is truncated at, or well-within, the Keplerian corotation radius. We find that although the structure of the surface magnetic field is particularly complex for both stars, the geometry of the larger scale field, along which accretion is occurring, is somewhat simpler. However, the larger scale field is distorted close to the star by the stronger field regions, with the net effect being that the fractional open flux through the stellar surface is less than would be expected with a dipole magnetic field model. Finally, we estimate the disc truncation radius, assuming that this occurs where the magnetic torque from the stellar magnetosphere is comparable to the viscous torque in the disc.Comment: 14 pages, 8 figures. Figures are reduced resolutio

show abstract

“…Spectra were processed as follows (Chountonov et al, 2007). Dark current, night sky emission and detector bias as well as cosmic ray traces were removed in a standard way, using routines from the MIDAS software package.…”

Section: Observations and Data Reductionmentioning

confidence: 99%

Magnetic field of the young star RW Aur

Додин¹,

Ламзин

Chuntonov

2012

Astron. Lett.

Self Cite

View full text Add to dashboard Cite

Results of longitudinal magnetic field B z measurements for young star RW Aur A are presented. We found that B z in the formation region of He I 5876 line's narrow component varies from −1.47 ± 0.15 kG to +1.10 ± 0.15 kG. Our data are consistent with a stellar rotational period of ≃ 5.6d and with a model of two hotspots with an opposite polarity of magnetic field and with a difference in a longitude about 180o . The spot with B z < 0 is located at the hemisphere above the midplane of RW Aur's accretion disc and the spot with B z > 0 is below the midplane.The following upper limits for B z (at 3σ level) were found after averaging of all our observations: 180 G for photosperic lines, 220 G and 230 G for formation regions of H α and [OI] 6300 lines respectively. Upper limit 600 G were found in the region where broad components of emisson lines form.For two cases out of 11 we observed the field in a formation region of a blue absorption wing of Na I D lines i.e. in an outflow: B z = −180 ± 50 G and −810 ± 80 G.Radial velocity of RW Aur's photospheric lines averaged over all our observations is ≃ +10.5 km s −1 what is 5.5 km s −1 less than value derived ten years earlier by Petrov et al. (2001). In this connection, we discuss a possibility that RW Aur is not a binary but a triple system.

show abstract

New results of magnetic field measurements for BP Tau

Cited by 9 publications

References 10 publications

Analysis of a 30-year series of photoelectric observations of RY Tauri. I. Search for possible periodicities

Analysis of a 30-year series of photoelectric observations of RY Tauri. I. Search for possible periodicities

The non-dipolar magnetic fields of accreting T Tauri stars

Magnetic field of the young star RW Aur

Contact Info

Product

Resources

About