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Despite their carbon-rich photospheres, silicate carbon stars show evidenceof oxygen-rich circumstellar material, which is considered to exist in disks.Silicate carbon stars represent interesting cases that allow us to study thepossible effects of binarity on stellar evolution and the mass loss accompaniedby the formation of disks. We present a small survey of the 22 GHz H2O maserstoward 10 silicate carbon stars with much better sensitivity than the previousobservations. We observed our sample with the Karl G. Jansky Very Large Array(VLA) using the most expanded configuration (A-configuration) with a maximumbaseline of 36 km. For some of our program stars with noisy IRAS Low ResolutionSpectra (LRS), we present new mid-IR spectra obtained with the Very LargeTelescope Interferometer and the Spitzer Space Telescope. We detected the H2Omasers toward 5 out of 10 silicate carbon stars (EU And, V778 Cyg,IRAS06017+1011, V1415 Cyg, and NC83=V1945 Cyg), with NC83 being new detection.No H2O masers were detected toward BM Gem, IRAS07221-0431, IRAS08002-3803,IRAS18006-3213, and HD189605. The velocity separation between the most blue-and red-shifted maser features is 10--14 km/s. If we assume that the masersoriginate in circum-companion disks, the measured velocity separationstranslate into a lower limit of the rotational velocity of 5--7 km/s, and theupper limit of the radius of the maser emitting region is estimated to be10--68 AU for a companion mass of 0.5--1.7 Msun. The new mid-IR spectra ofNC83, IRAS06017+1011, and HD189605 confirm the 10 micron silicate emission. Thelatter two stars show a bump at ~11.5 micron, which is presumably due to SiCoriginating in the ongoing mass loss from the carbon-rich primary star, not dueto crystalline silicate. We also report on the detection of the UV flux at 2271A toward HD189605.

VLA survey of the 22 GHz H2O masers toward 10 silicate carbon stars