Neutron Star Structure from Pulsar Observations

Symposium - International Astronomical Union ◽

10.1017/s0074180900100026 ◽

1974 ◽

Vol 53 ◽

pp. 189-207 ◽

Cited By ~ 3

Author(s):

David Pines ◽

Jacob Shaham ◽

Malvin A. Ruderman

Keyword(s):

Neutron Star ◽

Crab Pulsar ◽

Vela Pulsar ◽

Neutron Core ◽

Star Structure

We examine what inferences can be made regarding neutron star structure from observations of micro- and macroglitch behavior. After considering various theories it seems plausible that crustquakes offer an explanation for the Crab microglitches, while corequakes can explain the Vela macroglitches. It is concluded that the Crab pulsar has a mass of less than 0.5 M⊙ and is ∼ 90% superfluid neutrons while the Vela pulsar may possess a solid neutron core and have a mass of ∼ 0.7 M⊙ with a superfluid neutron abundance of ∼ 15%.

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Pulsar glitches in a strangeon star model. II. The activity

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa3520 ◽

2020 ◽

Vol 500 (4) ◽

pp. 5336-5349

Author(s):

W H Wang ◽

X Y Lai ◽

E P Zhou ◽

J G Lu ◽

X P Zheng ◽

...

Keyword(s):

Neutron Star ◽

Shear Modulus ◽

Energy Release ◽

Phenomenological Model ◽

Crab Pulsar ◽

Star Model ◽

Radio Pulsars ◽

Recovery Coefficient ◽

Star Models ◽

Vela Pulsar

ABSTRACT Glitch is supposed to be a useful probe into pulsar’s interior, but the underlying physics remains puzzling. The glitch activity may reflect a lower limit of the crustal moment of inertia in conventional neutron star models. Nevertheless, its statistical feature could also be reproduced in the strangeon star model, which is focused here. We formulate the glitch activity of normal radio pulsars under the framework of starquake of solid strangeon star model, the shear modulus of strangeon matter is constrained to be $\mu \simeq 3\times 10^{34}~\rm erg\,cm^{-3}$, consistent with previous work. Nevertheless, about ten times the shift in oblateness accumulated during glitch interval is needed to fulfill the statistical observations. The fact that typical glitch sizes of two rapidly evolving pulsars (the Crab pulsar and PSR B0540-69) are about two orders of magnitude lower than that of the Vela pulsar, significantly lower than the oblateness change they can supply, indicates probably that only a part of oblateness change is relieved when a pulsar is young. The unreleased oblateness and stress may relax as compensation in the following evolution. The small glitch sizes and low glitch activity of the Crab pulsar can be explained simultaneously in this phenomenological model. Finally, we obtain energy release to be $\Delta E\sim 2.4\times 10^{40}~\rm erg$ and $\Delta E\sim 4.2\times 10^{41}~\rm erg$ for typical glitch size of Δν/ν ∼ 10−6 (Vela-like) and ∼10−8 (Crab-like). The upcoming SKA may test this model through the energy release and the power-law relation between the reduced recovery coefficient $Q/|\dot{\nu }|^{1/2}$ and Δν/ν.

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Pulse Timing and Neutron Star Structure

Symposium - International Astronomical Union ◽

10.1017/s0074180900093037 ◽

1981 ◽

Vol 95 ◽

pp. 279-290

Author(s):

Paul E. Boynton

Keyword(s):

Neutron Star ◽

Timing Analysis ◽

Crab Pulsar ◽

X Ray ◽

Pulse Timing ◽

Star Structure

The implementation of pulse timing analysis as a probe of neutron star structure is reviewed for both pulsars and X-ray pulsators. Current results are particularly significant for the Crab pulsar.

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