Observations of pulsars at low radio frequencies

Thesis/Dissertation · Sun Jan 01 04:00:00 EST 1989

OSTI ID:6062904

Reyes, F J

The emission of pulsars at low radio frequencies (less than 50 MHz) presents several unique characteristics which are related to the configuration and physical conditions of the magnetosphere at large distances from the neutron star. However, the existing data at low radio frequencies is scarce, due to the lack of adequate instruments and to intrinsic difficulties in carrying out the observations. Several intense, low-dispersion, long-period pulsars were observed, using the University of Chile 45 MHz radiotelescope and the University of Florida 26.3 MHz radiotelescope. A total of eleven pulsars were observed at 45 and 26.3 MHz. All pulsars were observed with one- or two-channel receivers and narrow bandwidths. Long term integration was used in order to improve the signal-to-noise ratio of the pulses. The data were digitized at sampling rates between 32 and 100 Hz. The basic parameters measured for the detected pulsars are given. The dispersion measure was computed using the delay of arrival times of the integrated pulse profiles. A collection of integrated pulse profiles for each of the detected pulsars is included. The measurements obtained at 45 and 26.3 MHz were compared with already published low frequency data. The results obtained were discussed in the context of current models of the pulsar magnetosphere. The results of the observations are consistent, within the context of the polar cap model, with emission originating in the distorted magnetic field at a distance comparable to the radius of the velocity-of-light cylinder.

• Research Organization: Florida Univ., Gainesville, FL (USA)
• OSTI ID: 6062904
• Country of Publication: United States
• Language: English

Related Subjects

640102* -- Astrophysics & Cosmology-- Stars & Quasi-Stellar
Radio & X-Ray Sources
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
COSMIC RADIO SOURCES
DATA
ELECTROMAGNETIC RADIATION
EMISSION SPECTRA
EXPERIMENTAL DATA
INFORMATION
MAGNETIC FIELDS
NUMERICAL DATA
PULSARS
RADIATIONS
RADIOWAVE RADIATION
SIGNAL-TO-NOISE RATIO
SPECTRA