Distribution and evolution of starspots on the RS CVn binary II Pegasi in 2004
Date
01/03/2014Funder
Grant ID
ST/J001651/1
ST/I000666/1
PP/D000890/1
ST/G001006/1
PP/F000065/1
Keywords
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Show full item recordAbstract
We present Doppler images of RS CVn-type binary II Peg based on two data sets obtained in 2004 February and November. In order to improve signal-to-noise ratio and reliability,we apply least-squares deconvolution technique to calculate average profiles from 2032 photospheric absorption lines. Both of the resulting surface images show a wide latitude distribution of starspots. Most spots are concentrated at a high-latitude belt above 60° and a low-latitude belt near equator. The starspots evolved dramatically between two observing runs, which may indicate shorter time-scale evolution in this epoch, especially for low-latitude belt. There is no stable preferred active longitude that can be found in our images. We also find out a possible phenomenon that the intermediate-latitude spot migrated poleward and merged with the high-latitude spot to make it stronger, which may reveal a more complex behaviour of starspots on II Peg. A potential change of orbital ephemeris zero-point was detected. This may imply an orbital period change of II Peg like other active close binaries.
Citation
Xiang , Y , Gu , S-H , Collier Cameron , A & Barnes , J R 2014 , ' Distribution and evolution of starspots on the RS CVn binary II Pegasi in 2004 ' , Monthly Notices of the Royal Astronomical Society , vol. 438 , no. 3 , pp. 2307-2316 . https://doi.org/10.1093/mnras/stt2345
Publication
Monthly Notices of the Royal Astronomical Society
Status
Peer reviewed
ISSN
0035-8711Type
Journal article
Description
This work is supported by National Natural Science Foundation of China through grants Nos. 10373023, 10773027 and 11333006, Chinese Academy of Sciences through project KJCX2-YW-T24.Collections
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