... IRAF

IRAF is distributed by the National Optical Astronomy Observatories, which are operated by the Association of Universities for Research in Astronomy, Inc., under cooperative agreement with the National Science Foundation.

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... evolution

As bright RGB stars have very extended envelopes, conservation of angular momentum requires extremely low surface rotation speeds of these stars; the broadening of absorption lines in their spectra cannot be used to determine $v\sin i$.

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