A search for diffuse bands in the circumstellar envelopes of post-AGB stars

التفاصيل البيبلوغرافية
العنوان: A search for diffuse bands in the circumstellar envelopes of post-AGB stars
المؤلفون: Luna, R., Cox, N. L. J., Satorre, M. A., Garcia-Hernandez, D. A., Suarez, O., Garcia-Lario, P.
سنة النشر: 2007
المجموعة: Astrophysics
مصطلحات موضوعية: Astrophysics
الوصف: In this work we present the results of a systematic search for diffuse bands (DBs, hereafter) in the circumstellar envelopes of a carefully selected sample of post-AGB stars. We concentrated on the analysis of 9 of the DBs most commonly found in the interstellar medium. The strength of these features is determined using high resolution optical spectroscopy and the results obtained are compared with literature data on field stars affected only by interstellar reddening. Based on the weak features observed in the subsample of post-AGB stars dominated by circumstellar reddening we conclude that the carrier(s) of these DBs must not be present in the circumstellar environment of these sources, or at least not under the excitation conditions in which DBs are formed. The conclusion is applicable to all the post-AGB stars studied, irrespective of the dominant chemistry or the spectral type of the star considered. A detailed radial velocity analysis of the features observed in individual sources confirms this result, as the Doppler shifts measured are found to be consistent with an interstellar origin.
Comment: Accepted for A&A
نوع الوثيقة: Working Paper
DOI: 10.1051/0004-6361:20065282
URL الوصول: http://arxiv.org/abs/0711.1843
رقم الأكسشن: edsarx.0711.1843
قاعدة البيانات: arXiv
الوصف
DOI:10.1051/0004-6361:20065282