In this paper, we present a database of class I methanol masers. The compiled information
from the available literature provides an open and fast access to the data on class I …

Context. IRAS 19312+ 1950 is an isolated infrared source that exhibits a characteristic quasi-
point-symmetric morphology in the near-and mid-infrared images and is also very bright in …

Context. The circumstellar ammonia (NH 3) chemistry in evolved stars is poorly understood.
Previous observations and modelling showed that NH 3 abundance in oxygen-rich stars is …

ABSTRACT IRAS 19312+ 1950 is a peculiar object that has eluded firm characterization
since its discovery, with combined maser properties similar to an evolved star and a young …

Water fountains (WFs) are thought to be objects in the morphological evolution of the
circumstellar envelopes of low-and intermediate-mass evolved stars, transitioning from …

We report the detection of a new class I methanol maser candidate from the 5 2− 4 1 E
transition (266.8 GHz). This methanol transition has been detected toward a nearby high …

We present the database of maser sources in H 2 O, OH and SiO lines that can be used to
identify and study variable stars at evolved stages. Detecting the maser emission in H 2 O …

We report the results of wide field CO mapping in the region of IRAS 19312+ 1950. This
Infrared Astronomical Satellite (IRAS) object exhibits SiO/H 2 O/OH maser emission, and is …

We present the database of maser sources in H2O, OH and SiO lines that can be used to
identify and study variable stars at evolved stages. Detecting the maser emission in H2O …

The physics and chemistry of the circumstellar envelopes (CSEs) of evolved stars are not
fully understood despite decades of research. This thesis addresses two issues in the study …