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Dear colleagues! I would like to send you observations of a new variable star (Brh V135), which I have discovered in a systematic CCD-based search for new variables. In each observing run typically 600 images are taken of several survey fields. The frames are processed automatically. Instruments: CCD-camera: Starlight Xpress SX (unfiltered) Telescope: Celestron-8 (20 cm Schmidt-Cassegrain) New variable star: new Brh V135 17 43 19.2 -03 30 21 (J2000) 13.9-14.1 (CCD) comments: Brh V135: GSC 2.2 S220033334724 The comparison star is GSC 5085 774 (14.0 mag), which has been checked for constant brightness. The variability of this object is confirmed by TASS observations: http://a188-l009.rit.edu/cgi-bin/tass_curve2.cgi?265.8302_-03.5058 John Greaves has kindly sent a comment: The TASS Mk III has two near contemporaneous V and Ic points which give V-Ic of ~4, which 2MASS J-Ks is around 1.5. There will be some reddening in this field, but at first glance it looks like a Carbon star from the colours. USNO B1.0 B1-B2 and R1-R2 show little difference, which with your own and the TASS Mk III Ic measures suggest a small amplitude. Semiregular LPV Carbon stars are not uncommon, and this star is probably another example. IRAS PSC gives it as brightest at 100 microns (~2 Jy flux) and half as bright at 12 microns (~1 Jy flux) and about 0.4 Jy flux at 20 and 60 microns. The 12 micron level relative to the others _may_ suggest some excess of flux due to graphite, whilst the 100 micron level may suggest some general warm extended circumstellar material about the object, as can be the case with Carbon stars. It is a Semiregular variable. I do not think it is a "SARV" as I believe they are restricted to the "oxygen rich" spectral type M stars. object YYMMDD(UT) mag(CCD) code Brh V135 030703.9194 14.12 Brh.BAV Brh V135 030706.9541 13.94 Brh.BAV Brh V135 030708.9277 13.99 Brh.BAV Brh V135 030711.9118 13.94 Brh.BAV Brh V135 030713.8868 13.95 Brh.BAV Brh V135 030715.8821 13.90 Brh.BAV Regards, Klaus Bernhard Klaus Bernhard Kafkaweg 5 A-4030 LINZ AUSTRIA kl.bernhard@aon.at http://mitglied.lycos.de/klausbernhard/
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