========================================================================== J/A+A/322/159 H_2_O maser emission from irregular variables (Szymczak+ 1997) The following files can be converted to FITS (extension .fit .fiz or .fiZ) table2 ==========================================================================
drwxr-xr-x 5 cats archive 4096 Jan 29 2012 [Up] drwxr-xr-x 2 cats archive 4096 Jun 16 11:04 [TAR file] -rw-r--r-- 1 cats archive 314 Jun 3 1997 .message -r--r--r-- 1 cats archive 3244 Jun 9 1997 ReadMe -r--r--r-- 1 cats archive 2591 May 27 1997 table2
Beginning of ReadMe : J/A+A/322/159 H2O maser emission from irregular variables (Szymczak+ 1997) ================================================================================ H_2_O maser emission from irregular variables Szymczak M., Engels D. <Astron. Astrophys. 322, 159 (1997)> =1997A&A...322..159S (SIMBAD/NED BibCode) ================================================================================ ADC_Keywords: Stars, variable ; Stars, masers Keywords: masers - stars: circumstellar matter - stars: mass-loss - stars: AGB, post-AGB - radio lines: stars Abstract: We have performed a search for the 22 GHz water maser line among 72 optically identified irregular and semiregular red variables. New detections were made of five stars, while only four of nine objects previously known as maser sources were redetected. The probability for the detection of H_2_O maser emission increases with V light amplitude, and with H-K and K-[12] colours just as in regular Mira and semiregular variables of SRa- and SRb-types. The detection rate of water masers is about 25% for nearby Lb objects (D<400pc) in the sample, comparable to that observed in the SRa and SRb stars. No masers were detected in objects with mass loss rates <=4x10^-8^M_sun_/yr. Maser luminosities are 10^41^-10^43^photons/s similar to that of the bluest Miras and typical SRa and SRb stars showing water maser emission. A comparison of our data on irregular stars with those previously obtained on SRa and SRb variables suggests that most radio and infrared properties are indistinguishable among both classes of objects.
© UDS/CNRS