SIMBAD references

We have searched for minutes to hours timescale optical modulation from SNR 1987 A due to occultation of the putative neutron star by passing dust clouds. For this study, photometric images of the supernova were taken at one minute intervals using the NTT at ESO. We did not detect significant optical variability on this timescale from the supernova against the background of the two nearby stars. Based on our findings, we cannot rule out the possibility of an optical pulsar. However, if the neutron star is temporally obscured, we set an upper limit on the magnitude of the pulsar in the R band 20.1.