Abstract. We report new spectroscopic observations of the peculiar emission-line star SS73 11, between 3200Å and 7200Å. A line list is provided with their suggested identifications. From the measurements of several forbidden and permitted emission lines of single ionized iron, we derived the color excess and the excitation temperature. We also discuss the nature of SS73 11 based on data obtained. The spectrum closely resembles not only η Car but also some proto-planetary nebulae. On the other hand we concluded that this object is not a B[e]-supergiant, a symbiotic star or a Herbig AeB[e]-star.

Abstract.A set of 45 dust envelopes of carbon stars has been modeled. Among them, 34 were selected according to their dust envelope class (as suggested by Sloan et al. 1998) and 11 are extreme carbon stars. The models were performed using a code that describes the radiative transfer in dust envelopes considering core/mantle grains composed by an α-SiC core and an amorphous carbon (A.C.) mantle. In addition, we have also computed models with a code that considers two kinds of grains -α-SiC and A.C. -simultaneously. Core-mantle grains seem to fit dust envelopes of evolved carbon stars, while two homogeneous grains are more able to reproduce thinner dust envelopes. Our results suggest that there exists an evolution of dust grains in the carbon star sequence. In the beginning of the sequence, grains are mainly composed of SiC and amorphous carbon; with dust envelope evolution, carbon grains are coated in SiC. This phenomena could perhaps explain the small quantity of SiC grains observed in the interstellar medium. However, in this work we consider only α-SiC grains, and the inclusion of β-SiC grains can perhaps change some of these results.

HD 326823 is a peculiar emission line object. In the literature it was considered as a pre-WN candidate. Based mainly on high resolution data, obtained with the FEROS spectrograph, we made an atlas covering 3800-9200 Å region. This atlas confirms the presence of several strong He i lines and numerous N lines. There is also a deficiency of H, indicating that this object is indeed in an evolved stage. In addition, with low resolution spectra, we obtained intensities of several lines.

We present new spectroscopic observations between 3100 and 5100 and 3500 and 7500 of the A A stars Hen 3-461, Hen 3-653, Hen 2-156, V704 Cen, Mac 1-17, V3804 Sgr, and V2905 Sgr. Except for V3804 Sgr, which presents a Ñat spectrum in the optical range, and V704 Cen, all the objects have latetype continuum spectra, and some have H I, He I, He II j4686, and [O III] j5007 emission lines. All the objects have been previously classiÐed as suspected symbiotic stars. We Ðnd that Ðve of them (Hen 3-461, Hen 2-156, Mac 1-17, V3804 Sgr, and V2905 Sgr) are symbiotic stars. The nature of two objects, Hen 3-653 and V704 Cen, is still uncertain despite their symbiotic behavior. We also present a discussion of the nature of each object.