Doppler imaging of stellar surface structure - XVI. A time-series analysisof the moderately-rotating K1-giant sigma Geminorum

Citation
Z. Kovari et al., Doppler imaging of stellar surface structure - XVI. A time-series analysisof the moderately-rotating K1-giant sigma Geminorum, ASTRON ASTR, 373(1), 2001, pp. 199-210
Citations number
49
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Space Sciences
Journal title
ASTRONOMY & ASTROPHYSICS
ISSN journal
1432-0746 → ACNP
Volume
373
Issue
1
Year of publication
2001
Pages
199 - 210
Database
ISI
SICI code
1432-0746(200107)373:1<199:DIOSSS>2.0.ZU;2-A
Abstract
We present a simultaneous photometric and spectroscopic imaging analysis of the long-period RS CVn binary sigma Gem, covering 3.6 consecutive rotation cycles with high time resolution. From six overlapping but consecutive Dop pler maps we trace the evolution of individual spots throughout the time ra nge covered. All spots group either along a band at approximately +45 degre es latitude and a width of 30 degrees, or appear centered at the equator. N o polar spot is detected. We did not find a conclusive migration pattern fr om the cross-correlation maps from one rotation to the next and attribute t his to a masking effect of short-term spot changes.