000002307 001__ 2307
000002307 005__ 20160701171703.0
000002307 0247_ $$2DOI$$a10.1051/0004-6361/200912025
000002307 037__ $$aASTROimport-464
000002307 100__ $$aBriquet, M.
000002307 245__ $$aGround-based observations of the ß Cephei CoRoT main target HD 180 642: abundance analysis and mode identification
000002307 260__ $$c2009
000002307 520__ $$aThe known ß Cephei star HD 180 642 was observed by the CoRoT satellite in 2007. From the very high-precision light curve, its pulsation frequency spectrum could be derived for the first time (Degroote and collaborators). In this paper, we obtain additional constraints for forthcoming asteroseismic modeling of the target. Our results are based on both extensive ground-based multicolour photometry and high-resolution spectroscopy. We determine T_eff = 24 500± 1000 K and log g = 3.45± 0.15 dex from spectroscopy. The derived chemical abundances are consistent with those for B stars in the solar neighbourhood, except for a mild nitrogen excess. A metallicity Z = 0.0099± 0.0016 is obtained. Three modes are detected in photometry. The degree l is unambiguously identified for two of them: l = 0 and l = 3 for the frequencies 5.48694 d-1 and 0.30818 d-1, respectively. The radial mode is non-linear and highly dominant with an amplitude in the U-filter about 15 times larger than the strongest of the other modes. For the third frequency of 7.36673 d-1 found in photometry, two possibilities remain: l = 0 or 3. In the radial velocities, the dominant radial mode presents a so-called stillstand but no clear evidence of the existence of shocks is observed. Four low-amplitude modes are found in spectroscopy and one of them, with frequency 8.4079 d-1, is identified as (l,m)=(3,2). Based on this mode identification, we finally deduce an equatorial rotational velocity of 38± 15 km s-1. Based on data gathered with the 1.2m Mercator telescope Roque de los Muchachos, La Palma, the 90cm telescope at Sierra Nevada Observatory, Spain, the 1.5 m telescope at San Pedro Mártir Observatory, Mexico, the 1m RCC and 50 cm telescope at the Piszkésteto Mountain Station of Konkoly Observatory, Hungary, the 2.2 m ESO telescope (ESO Programme 077.D-0311; ESO Large Programme 178.D-0361) at La Silla, Chile, the 1.93 m and 1.52 m telescopes at the Haute-Provence Observatory, France. Current address: Laboratoire AIM, CEA/DSM-CNRS-Université Paris Diderot; CEA, IRFU, SAp, centre de Saclay, 91191 Gif-sur-Yvette, France. 
000002307 700__ $$a Uytterhoeven, K.
000002307 700__ $$a Morel, T.
000002307 700__ $$a Aerts, C.
000002307 700__ $$a De Cat, P.
000002307 700__ $$a Mathias, P.
000002307 700__ $$a Lefever, K.
000002307 700__ $$a Miglio, A.
000002307 700__ $$a Poretti, E.
000002307 700__ $$a Martín-Ruiz, S.
000002307 700__ $$a Paparó, M.
000002307 700__ $$a Rainer, M.
000002307 700__ $$a Carrier, F.
000002307 700__ $$a Gutiérrez-Soto, J.
000002307 700__ $$a Valtier, J. C.
000002307 700__ $$a Benko, J. M.
000002307 700__ $$a Bognár, Z.
000002307 700__ $$a Niemczura, E.
000002307 700__ $$a Amado, P. J.
000002307 700__ $$a Suárez, J. C.
000002307 700__ $$a Moya, A.
000002307 700__ $$a Rodríguez-López, C.
000002307 700__ $$a Garrido, R.
000002307 773__ $$c269-280$$i1$$pAstronomy and Astrophysics$$v506$$y2009
000002307 85642 $$ahttp://esoads.eso.org/abs/2009A%26A...506..269B
000002307 905__ $$apublished in
000002307 980__ $$aREFERD