John Metcalf Rankin

Individual pulse polarization properties of three pulsars

Both average and individual pulse polarization measurements at 430 MHz are presented for three pulsars: PSR 0823 + 26, PSR 0834 + 06, and PSR 2303 + 30. In each case, the average Stokes parameter waveformes are found to depend on the individual pulse polarization properties in a complicated manner. The average waveforms are in general depolarized by pulse-to-pulse fluctuations in polarization state at a given longitude. Two of the three objects exhibit variations of both linear and circular polarization which are associated with quasi-periodic subpulse modulation phenomena in a manner similar to that reported for linear polarization in PSR 0809 + 74 by Taylor et al. (1971.).

Short-duration radio flares of UV Ceti stars

The UV Ceti-type stars YZ Canis Minoris, AD Leonis, Wolf 424, and V371 Orionis were monitored with the Arecibo radio telescope at meter wavelengths. A total of 26 flares were recorded on YZ CMi, AD Leo, and Wolf 424. The observed flares had shorter durations and smaller amplitudes than those previously reported in the literature. Rates of radio-flare detection are similar to those found optically.

QUASI-SINUSOIDAL OSCILLATION IN ARRIVAL TIMES OF PULSES FROM NP 0532.

Crab Nebula pulsar NP 0532, describing quasi- sinusoidal oscillation in arrival times of radio pulses

Four-Stokes-parameter radiofrequency polarimetry of a flare from AD Leonis

Observations of the four Stokes parameters of a 430-MHz flare from the UV Ceti-type star AD Leo are presented. The maximum amplitude of the event was 0.52 flux units, and the durations at one-half and one-tenth maximum were 12 and 40 sec, respectively. The degree of circular polarization at maximum intensity was approximately 56% and was later observed to be as high as 92%. Linear polarization was also observed at a level of about 21% at flare maximum which allowed an upper limit of 440 radians/sq m to be placed on the rotation measure.