000002060 001__ 2060
000002060 005__ 20160701171658.0
000002060 0247_ $$2DOI$$a10.1051/0004-6361:20041901
000002060 037__ $$aASTROimport-217
000002060 100__ $$aNeiner, C.
000002060 245__ $$aRotation, pulsations and outbursts in the Be star υ Cygni (HD 202904)
000002060 260__ $$c2005
000002060 520__ $$aυ Cyg is a Be star that shows variations at all timescales. We monitored its spectrum for several years from 1998 to 2004 and, in particular, during a spectroscopic multisite campaign in 2000. In this paper we present and analyse the data. We observed several outbursts including an intense one in 2000. Moreover, we found several periods of short-term variations, including two frequencies at 2.95 and 2.6 c d-1, which are well reproduced by models of non radial pulsations with a retrograde mode with ℓ=3 and m=3 and a zonal mode with ℓ=3 or 4 and m=0, respectively. The stellar rotation is probably also identified at f˜1.5 c d-1, which is coherent with the rotation frequency deduced from our determination of stellar parameters. The peak-to-peak amplitude of variations also seems to vary in time, maybe due to a beating effect between close frequencies, but the resolution in time of our data does not allow us to separate such close frequencies. Finally, a longer timescale variation may be present, with a period around 11 years, which could be associated with a binary companion. 
000002060 700__ $$a Floquet, M.
000002060 700__ $$a Hubert, A. M.
000002060 700__ $$a Frémat, Y.
000002060 700__ $$a Hirata, R.
000002060 700__ $$a Masuda, S.
000002060 700__ $$a Gies, D.
000002060 700__ $$a Buil, C.
000002060 700__ $$a Martayan, C.
000002060 773__ $$c257-272$$i1$$pAstronomy and Astrophysics$$v437$$y2005
000002060 85642 $$ahttp://esoads.eso.org/abs/2005A%26A...437..257N
000002060 905__ $$apublished in
000002060 980__ $$aREFERD