M. Parthasarathy, J. S. Drilling, J. Vijapurkar, Y. Takeda
Hot (OB) post-AGB stars are immediate progenitors of planetary nebulae (PNe).
Very few hot post-AGB stars are known. Detecting new hot post-AGB candidates
and follow-up multiwavelength studies will enable us to further understand the
processes during the post-AGB evolution that lead to the formation of PNe.
Case-Hamburg OB star surveys and their extension (LS, LSS, and LSE catalogues)
and IRAS (point source) catalogues are good sources for detecting new hot
post-AGB candidates from low resolution spectroscopy. Spectral types are
determined from low resolution optical spectra of 44 stars selected from the
LS, LSS, and LSE catalogues. Unlike the stars in the first paper, the stars in
this paper were selected using criteria other than positional coincidence with
an IRAS source with far IR (IRAS) colours similar to post-AGB supergiants and
planetary nebulae. These included high galactic latitude, spectral types of O,
B, A supergiants, emission lines in the spectrum and known spectral
peculiarity. From the present study we find that LSS 1179, LSS 1222, LSS 1256,
LSS 1276, LSS 1341, LSS 1394, LSS 2241, LSS 2429, LSS 4560, LSE 16, LSE 31, LSE
42, and LSE 67 to be new hot post-AGB candidates. Further study of these
candidates is needed.
View original:
http://arxiv.org/abs/1112.3104
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