Photopolarimetric activity of the Ae Herbig star SV Cep

Rostopchina, A. N.; Гринин, В. П.; Shakhovskoi, D. N.; Миникулов, Н. Х.

doi:10.1134/1.163860

Cited by 20 publications

(27 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…their light curves show high-amplitude variability (∆m > 2.0 mag), Algol-like minima, a blueing effect and an increase of the polarization when the object brightness decreases. SV Cep also shows UXOR characteristics (Rostopchina et al 2000;Oudmaijer et al 2001). Further data are required before XY Per can be confidently classed as a UXOR-type object (Oudmaijer et al 2001), although it does share the same complex and variable spectroscopic behaviour of the other stars.…”

Section: Discussionmentioning

confidence: 99%

Dynamics of the circumstellar gas in the Herbig Ae stars BF Orionis, SV Cephei, WW Vulpeculae and XY Persei

Mora

Eiroa

Natta

et al. 2004

A&A

View full text Add to dashboard Cite

Abstract. We present high resolution (λ/∆λ = 49 000)échelle spectra of the intermediate mass, pre-main sequence stars BF Ori, SV Cep, WW Wul and XY Per. The spectra cover the range 3800−5900 Å and monitor the stars on time scales of months and days. All spectra show a large number of Balmer and metallic lines with variable blueshifted and redshifted absorption features superimposed to the photospheric stellar spectra. Synthetic Kurucz models are used to estimate rotational velocities, effective temperatures and gravities of the stars. The best photospheric models are subtracted from each observed spectrum to determine the variable absorption features due to the circumstellar gas; those features are characterized in terms of their velocity, v, dispersion velocity, ∆v, and residual absorption, R max . The absorption components detected in each spectrum can be grouped by their similar radial velocities and are interpreted as the signature of the dynamical evolution of gaseous clumps with, in most cases, solar-like chemical composition. This infalling and outflowing gas has similar properties to the circumstellar gas observed in UX Ori, emphasizing the need for detailed theoretical models, probably in the framework of the magnetospheric accretion scenario, to understand the complex environment in Herbig Ae (HAe) stars. WW Vul is unusual because, in addition to infalling and outflowing gas with properties similar to those observed in the other stars, it shows also transient absorption features in metallic lines with no obvious counterparts in the hydrogen lines. This could, in principle, suggest the presence of CS gas clouds with enhanced metallicity around WW Vul. The existence of such a metal-rich gas component, however, needs to be confirmed by further observations and a more quantitative analysis.

show abstract

Section: Discussionmentioning

confidence: 99%

Dynamics of the circumstellar gas in the Herbig Ae stars BF Orionis, SV Cephei, WW Vulpeculae and XY Persei

Mora

Eiroa

Natta

et al. 2004

A&A

View full text Add to dashboard Cite

show abstract

“…The minimum in the V band photometry corresponds to a hardly significant local maximum in polarization but is more visible in the R band data, which are also shown for this object. RR Tau is known to display the UXOR phenomenon, as Rostopchina et al (1997) has shown. They find that the V band magnitude varies between 10 and 14, with excursions in the polarization up to 6%.…”

Section: Objects Showing Increased Polarization With Fainter Magnitudesmentioning

confidence: 99%

“…A recent paper by Rostopchina et al (2000) presents 10 year long monitoring of the star, and only one deep minimum was detected. Indeed.…”

Section: Objects Not Showing Increased Polarization With Fainter Magnmentioning

confidence: 99%

EXPORT: Optical photometry and polarimetry of Vega-type and pre-main sequence stars

Oudmaijer

Palacios

Eiroa

et al. 2001

A&A

100

112

View full text Add to dashboard Cite

Abstract. This paper presents optical UBVRI broadband photo-polarimetry of the EXPORT sample obtained at the 2.5m Nordic Optical Telescope. The database consists of multi-epoch photo-polarimetry of 68 pre-mainsequence and main-sequence stars. An investigation of the polarization variability indicates that 22 objects are variable at the 3σ level in our data. All these objects are pre-main sequence stars, consisting of both T Tauri and Herbig Ae/Be objects while the main sequence, Vega type and post-T Tauri type objects are not variable. The polarization properties of the variable sources are mostly indicative of the UXOR-type behaviour; the objects show highest polarization when the brightness is at minimum. We add nine new objects to the class of UXOR variables (BH Cep, VX Cas, DK Tau, HK Ori, LkHα 234, KK Oph and RY Ori). The main reason for their discovery is the fact that our data-set is the largest in its kind, indicating that many more young UXOR-type pre-main sequence stars remain to be discovered. The set of Vega-like systems has been investigated for the presence of intrinsic polarization. As they lack variability, this was done using indirect methods, and apart from the known case of BD +31 o 643, the following stars were found to be strong candidates to exhibit polarization due to the presence of circumstellar disks: 51 Oph, BD +31 o 643C, HD 58647 and HD 233517.

show abstract

“…Herbig Ae stars seem to be the most promising objects to look for such periodicities. Light curves of the stars were analysed in details in [9][10][11][12][13][14][15], but no stable periods were detected. At longer time intervals of months and years, wave-like variations of the maximum level of brightness were found.…”

Section: Introductionmentioning

confidence: 99%

A search for Keplerian periods in the brightness variations of T Tauri and Ae Herbig stars

2010

View full text Add to dashboard Cite

Long-term, uniform series of UBVR observations of T Tauri and Herbig Ae stars obtained over 20 yr at the Maidanak Observatory as part of the ROTOR program are analyzed. We find a linear relationship between the characteristic variability time scale and the bolometric luminosity of the star+disk system: the higher the luminosity, the slower the brightness variations. This dependence is valid over a wide range of masses and luminosities, from T Tauri stars to Herbig Ae stars. On average, the variability time scale is one-quarter the Keplerian period at the dust-sublimation radius, which is known from interferometric observations. Some T Tauri stars have periods from 25 to 120 days, which are preserved over several observing seasons. These periods correspond to Keplerian orbits with semi-major axes from 0.14 to 0.52 AU. The results obtained provide indirect evidence for the existence of protoplanets in the gas-dust disks of stars in early stages of their evolution toward the main sequence.

show abstract

Photopolarimetric activity of the Ae Herbig star SV Cep

Cited by 20 publications

References 8 publications

Dynamics of the circumstellar gas in the Herbig Ae stars BF Orionis, SV Cephei, WW Vulpeculae and XY Persei

Dynamics of the circumstellar gas in the Herbig Ae stars BF Orionis, SV Cephei, WW Vulpeculae and XY Persei

EXPORT: Optical photometry and polarimetry of Vega-type and pre-main sequence stars

A search for Keplerian periods in the brightness variations of T Tauri and Ae Herbig stars

Contact Info

Product

Resources

About