Identification of OH/IR Stars from Color Selected IRAS Sources

Abstract

Efficient all-sky surveys for OH/IR stars can be completed from 1612 MHz line-searches at the positions of color-selected IRAS sources. This approach can easily detect sources of ~50 mJy, so giving a 20 fold improvement in sensitivity. Results of both a 1612 MHz and a 1665/7 MHz survey from Arecibo are presented. These show that color-selected samples include sources with three distinctly different galactic latitude distributions. Objects with (60–25) µm > -0.9 are rarer than the others, have a narrow distribution about the galactic plane, and so come from short-lived massive progenitors. Far-IR colors of sources in the galactic plane, require adjustment for interstellar extinction.