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The rotation of more than 700 pulsars has been monitored using the 76-m Lovell Telescope at Jodrell Bank. Here we report on a new search for glitches in the observations, revealing 128 new glitches in the rotation of 63 pulsars. Combining these new data with those already published we present a database containing 315 glitches in 102 pulsars. The database was used to study the glitch activity among the pulsar population, finding that it peaks for pulsars with a characteristic age tau_c ~ 10kyr and decreases for longer values of tau_c, disappearing for objects with tau_c > 20Myr. The glitch activity is also smaller in the very young pulsars (tau_c <~ 1kyr). The cumulative effect of glitches, a collection of instantaneous spin up events, acts to reduce the regular long term spindown rate |nudot| of the star. The percentage of |nudot| reversed by glitch activity was found to vary between 0.5% and 1.6% for pulsars with spindown rates |nudot| between 10^(-14) and 3.2*10^(-11) Hz/s, decreasing to less than 0.01% at both higher and lower spindown rates. These ratios are interpreted in terms of the amount of superfluid involved in the generation of glitches. In this context the activity of the youngest pulsar studied, the Crab pulsar, may be explained by quake-like activity within the crust. Pulsars with low spindown rates seem to exhibit mostly small glitches, matching well the decrease of their crustal superfluid. Through the analysis of glitch sizes it was found that the particular glitching behaviour of PSR J0537-6910 and the Vela pulsar may be shared by most Vela-like pulsars. These objects present most of their glitches with characteristic frequency and frequency derivative jumps, occurring at regular intervals of time. Their behaviour is different from other glitching pulsars of similar characteristic age.
Several glitches have been observed in young, isolated radio pulsars, while a clear detection in accretion-powered X-ray pulsars is still lacking. We use the Pizzochero snowplow model for pulsar glitches as well as starquake models to determine for t
Timing observations from the Parkes 64-m radio telescope for 165 pulsars between 1990 and 2011 have been searched for period glitches. A total of 107 glitches were identified in 36 pulsars, where 61 have previously been reported and 46 are new discov
The abrupt change in the pulse period of a pulsar is called a pulsar glitch. In this paper, we present eleven pulsar glitches detected using the Ooty Radio Telescope (ORT) and the upgraded Giant Metrewave Radio Telescope (uGMRT) in high cadence timin
Data are gathered from the Parkes pulsar data archive of twelve young radio pulsars, with the intervals of data for each pulsar ranged between 2.8 years and 6.8 years. 31 glitches are identified by using phase connection from pulsar timing technology
In this paper, we discuss the impact of rotation on the particle composition of rotating neutron stars (pulsars). Particular emphasis is put on the formation of quark matter during stellar spin-down, driven by continuous gravitational compression. Ou