Magnetic field topology of the RS CVn star II Pegasi
نویسندگان
چکیده
منابع مشابه
The chromosphere of II Pegasi: multi-line modelling of an RS Canum Venaticorum star
We present the first simultaneous multi-line fitting of a semi-empirical atmospheric model with a chromosphere and transition region to the H I and Ca II spectra of an RS CVn star (II Peg). The static component of the Hα emission core, the line profile of Hβ, the apparent absence of Hγ and Hδ, and the emission core profiles of Ca II K and two of the Ca II IR3 lines are all approximately fitted ...
متن کاملA probable RS CVn star which sometimes stops its eclipses ⋆
We report the discovery of a new variable star, called S 10947 Aql, as the likely optical counterpart of RX J2009.8+1557. The optical variability pattern as well as the detected X-ray emission suggest that it is a chromospherically active binary of the RS Canum Venaticorum (≡ RS CVn) type. We discovered an occasional disappearance of the eclipsing minima as well as large variations in the eclip...
متن کاملThe active RS Canum Venaticorum binary II Pegasi
A total of 6 new surface images of II Peg obtained for the years 1997 and 1998 confirms the recently revealed permanent active longitude structure. The lower limit of the active longitudes’ lifetime is now extended up to 25 years. A new “flipflop” phenomenon, redefined as a switch of the activity between the active longitudes, has started in summer of 1998. It coincides reasonably well with the...
متن کاملVLBI imaging of the RS CVn binary star system HR 5110
We present VLBI images of the RS CVn binary star HR 5110 (=BH CVn; HD 118216), obtained from observations made at 8.4 GHz on 1994 May 29/30 in support of the NASA/Stanford Gravity Probe B project. Our images show an emission region with a core-halo morphology. The core was 0.39 ± 0.09 mas (FWHM) in size, or 66%±20% of the 0.6 ±0.1 mas diameter of the chromospher-ically active K subgiant star in...
متن کاملVLA multifrequency observations of RS CVn binaries
We present multiepoch Very Large Array (VLA) observations at 1.4 GHz, 4.9 GHz, 8.5 GHz and 14.9 GHz for a sample of eight RS CVn binary systems. Circular polarization measurements of these systems are also reported. Most of the fluxes observed are consistent with incoherent emission from mildly relativistic electrons. Several systems show an increase of the degree of circular polarization with ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Astronomy & Astrophysics
سال: 2013
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361/201220432