000002308 001__ 2308
000002308 005__ 20160701171703.0
000002308 0247_ $$2DOI$$a10.1051/0004-6361/200911971
000002308 037__ $$aASTROimport-465
000002308 100__ $$aNeiner, C.
000002308 245__ $$aThe pulsations of the B5IVe star HD 181231 observed with CoRoT and ground-based spectroscopy
000002308 260__ $$c2009
000002308 520__ $$aContext: HD 181231 is a B5IVe star, which has been observed with the CoRoT satellite during ~5 consecutive months and simultaneously from the ground in spectroscopy and spectropolarimetry. Aims: By analysing these data, we aim to detect and characterize as many pulsation frequencies as possible, to search for the presence of beating effects possibly at the origin of the Be phenomenon. Our results will also provide a basis for seismic modelling.  Methods: The fundamental parameters of the star are determined from spectral fitting and from the study of the circumstellar emission. The CoRoT photometric data and ground-based spectroscopy are analysed using several Fourier techniques: Clean-ng, Pasper, and Tisaft, as well as a time-frequency technique. A search for a magnetic field is performed by applying the LSD technique to the spectropolarimetric data.  Results: We find that HD 181231 is a B5IVe star seen with an inclination of ~45 degrees. No magnetic field is detected in its photosphere. We detect at least 10 independent significant frequencies of variations among the 54 detected frequencies, interpreted in terms of non-radial pulsation modes and rotation. Two longer-term variations are also detected: one at ~14 days resulting from a beating effect between the two main frequencies of short-term variations, the other at ~116 days due either to a beating of frequencies or to a zonal pulsation mode.  Conclusions: Our analysis of the CoRoT light curve and ground-based spectroscopic data of HD 181231 has led to the determination of the fundamental and pulsational parameters of the star, including beating effects. This will allow a precise seismic modelling of this star. Based on observations obtained with the CoRoT satellite, with FEROS at the 2.2 m télescope of the La Silla Observatory under the ESO Large Programme LP178.D-0361, with Narval at the Télescope Bernard Lyot of the Pic du Midi Observatory, and collected from the BeSS database. Table 5 is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/506/143 
000002308 700__ $$a Gutiérrez-Soto, J.
000002308 700__ $$a Baudin, F.
000002308 700__ $$a de Batz, B.
000002308 700__ $$a Frémat, Y.
000002308 700__ $$a Huat, A. L.
000002308 700__ $$a Floquet, M.
000002308 700__ $$a Hubert, A.-M.
000002308 700__ $$a Leroy, B.
000002308 700__ $$a Diago, P. D.
000002308 700__ $$a Poretti, E.
000002308 700__ $$a Carrier, F.
000002308 700__ $$a Rainer, M.
000002308 700__ $$a Catala, C.
000002308 700__ $$a Thizy, O.
000002308 700__ $$a Buil, C.
000002308 700__ $$a Ribeiro, J.
000002308 700__ $$a Andrade, L.
000002308 700__ $$a Emilio, M.
000002308 700__ $$a Espinosa Lara, F.
000002308 700__ $$a Fabregat, J.
000002308 700__ $$a Janot-Pacheco, E.
000002308 700__ $$a Martayan, C.
000002308 700__ $$a Semaan, T.
000002308 700__ $$a Suso, J.
000002308 700__ $$a Baglin, A.
000002308 700__ $$a Michel, E.
000002308 700__ $$a Samadi, R.
000002308 773__ $$c143-151$$i1$$pAstronomy and Astrophysics$$v506$$y2009
000002308 85642 $$ahttp://esoads.eso.org/abs/2009A%26A...506..143N
000002308 905__ $$apublished in
000002308 980__ $$aREFERD