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We present a single pulse study of pulsar B1944+17, whose non-random nulls dominate nearly 70% of its pulses and usually occur at mode boundaries. When not in the null state, this pulsar displays four bright modes of emission, three of which exhibit drifting subpulses. B1944+17 displays a weak interpulse whose position relative to the main pulse we find to be frequency independent. Its emission is nearly 100% polarized, its polarization-angle traverse is very shallow and opposite in direction to that of the main pulse, and it nulls approximately two-thirds of the time. Geometric modeling indicates that this pulsar is a nearly aligned rotator whose alpha value is hardly 2 degrees--i.e., its magnetic axis is so closely aligned with its rotation axis that its sightline orbit remains within its conal beam. The stars nulls appear to be of two distinct types: those with lengths less than about 8 rotation periods appear to be pseudonulls--that is, produced by empty sightline traverses through the conal beam system; whereas the longer nulls appear to represent actual cessations of the pulsars emission engine.
In the canonical picture of pulsars, radio emission arises from a narrow cone centered on the stars magnetic axis but many basic details remain unclear. We use high-quality polarization data taken with the Parkes radio telescope to constrain the geom
We present a single-pulse study of the four-component pulsar J1819+1305, whose ``null pulses bunch at periodic intervals of around 57 times the rotation period. The emission bursts between the null bunches exhibit characteristic modulations at two sh
We performed Monte Carlo simulations of different properties of pulsar radio emission, such as: pulsar periods, pulse-widths, inclination angles and rates of occurrence of interpulse emission (IP). We used recently available large data sets of the pu
We present timing solutions and spin properties of the young pulsar PSR B0540-69 from analysis of 15.8 yr of data from the Rossi X-Ray Timing Explorer. We perform a partially phase-coherent timing analysis in order to mitigate the pronounced effects
On the ground of the large number of gamma-ray bursts (GRBs) detected with cosmological redshift, we classified GRBs in seven subclasses, all with binary progenitors originating gravitational waves (GWs). Each binary is composed by combinations of ca