LHIRES III SPECTROSCOPIC SURVEY OF COROT Be STARS

Introduction

The COROT (COnvection ROtation and planetary Transits) satellite has two main goals: study the interior of stars by looking at their oscillations and seach for extrasolar planets by detecting planetary transits. The 30-cm telescope of COROT will be pointed alternatively towards the galactic center and anticenter.

Bright Be stars can therefore be observed either as secondary targets asteroseismology in long runs or as short run targets. COROT can detect pulsations in Be stars, especially multiperiodicity and beating periods in early Be stars and low-amplitude pulsations in late Be stars (see Y. Frémat & all, A&A 451, 1053 (2006) and C. Neiner & all, ApJS, 152, 237 (2005)). The present survey concern the spectroscopic observations by amateurs of candidates Be stars located in the seismology fields. Regular observations of the spectroscopic activity of these stars are programmed before and after the launch of COROT satellite.

The idea of the survey by amateurs was impulsed by Coralie Neiner (GEPI - Observatoire de Paris-Meudon) during the Astrophysics School of La Rochelle 2006 (CNRS). The program coincide with the availability of has powerful instrument for the amateur community, the spectrograph LHIRES III (see description here). LHIRES III is an ARAS project (Astronomical Ring for Access to Spectroscopy). The stars of this sample forms a subset of a large long term program of Be stars observations (see here).

Web:
COROT site: http://corot.oamp.fr/
CNES site: http://smsc.cnes.fr/COROT/Fr/index.htm
COROT Be stars group: http://www.ster.kuleuven.be/~coralie/shortruns.html
ARAS site: http://astrosurf.com/aras/
La Rochelle 2006: http://www.astrosurf.com/thizy/rochelle2006/rochelle2006.htm

Winter 2006 run - Anticenter targets

HD50820 - the first probable Be star target of Corot mission
Short time evolution:

 
Download data:

_50820_20061106_028.DAT
_50820_20061214_966.DAT
_50820_20061219_996.DAT
_50820_20061226_907.DAT
_50820_20070106_058.DAT
_50820_20070109_984.DAT
_50820_20070117_986.DAT
 

Spring 2006 run - Galactic center targets

The data of the run were obtained with the LHIRES III spectrograph at the medium resolution of R=7000 (1200 lines/mm grating). The spectroscopic observations where conducted on a 0.28 m telescope located near Toulouse city, south of France (Castanet-Tolosan observatory) and the 0.60 m Gentili telescope of the Pic-du-Midi observatory (Observatoire Midi-Pyrénées).

All the selected galactic center Be stars targets are observed during the run (see the list of candidates Be stars secondary targets of COROT mission). The present wavelength intervals cover the Ha line and the He I 6677 A line. The data are reduced by using LHIRES III standard procedures (SpIRIS and VisualSpec softwares).
 

Some images of the setup

The control room of the 0.60 m telescope.

The spring 2006 run team. From left to right, Michel Pujol, Valérie Desnoux, Christian Buil.
Click here for more details about the spring 2006 Pic-du-Midi mission.

Position of some COROT Be stars on the sky (galactic field)

Some of the program Be stars are identified in the field below:

Stack of 4 frames (exposed each 3 minutes) taken with a Canon EOS 5D Digital SLR
and a Canon 24-70 mm f:2.8 zoom (used at 70 mm f:2.8). Images taken the July 27, 2006
during the run#1 mission at the Pic du Midi observatory.
Click on the image for enlarge.

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