1994A&A...286..211J

We report on new photometric, CORAVEL and spectroscopic observations carried out between 1988 and 1991 of the visible G5III central star HD 112313 of the planetary nebula LoTr5 which each of them confirm variability. The power spectrum of our photometric data collected in March 1989 is similar to those of previous observers but cannot help to decide the true period(s). Radial-velocity measurements of the H_α absorption line obtained in May 1990, January 1991 and April 1991 seem to have a pattern of power spectra similar to photometry. CORAVEL radial-velocity measurements of HD 112313 are of poor quality due to a very wide correlation dip with poor contrast, origin of which should be the high rotational velocity of the G-star (v.sini∼70km/s) and possible drastic changes in the spectrum within the course of some hours. The radial-velocity variations of the iron lines shown by CORAVEL are irregular and no stable period appears among five yearly observing runs (about seven days each one), though the pattern of power spectra for June 1988 and July 1989 is also similar to the photometric one.