SIMBAD references

We present rapid radial velocity measurements (σ∼55 m/s) for the roAp star α Cir made using a molecular iodine gas absorption cell. A period analysis places an upper limit of 60 m/s for the peak-to-peak amplitude of any radial velocity variations in the frequency range 20 to 375 days^–1. Phasing the measurements to the known photometric period of 6.83 minutes results in an upper limit of 36 m/s (peak-to-peak) for the radial velocity amplitude of the pulsations. This yields an upper limit to the ratio of radial velocity amplitude to photometric amplitude (2K/{DELTA}m_B) of about 10 km/s/mag, substantially less than was found for two other roAp stars by other investigators.