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The Nuclear Spectroscopic Telescope Array (NuSTAR) is the first focusing hard X-ray mission in orbit and operates in the 3-79 keV range. NuSTAR's sensitivity is roughly two orders of magnitude better than previous missions in this energy band thanks to its superb angular resolution. Since its launch in 2012 June, NuSTAR has performed excellently and observed many interesting sources including four magnetars, two rotation-powered pulsars and the cataclysmic variable AE Aquarii. NuSTAR also discovered 3.76-s pulsations from the transient source SGR J1745-29 recently found by Swift very close to the Galactic center, clearly identifying the source as a transient magnetar. For magnetar 1E 1841-045, we show that the spectrum is well fit by an absorbed blackbody plus broken power-law model with a hard power-law photon index of ∼ 1.3. This is consistent with previous results by INTEGRAL and RXTE. We also find an interesting double-peaked pulse profile in the 25-35 keV band. For AE Aquarii, we show that the spectrum can be described by a multi-temperature thermal model or a thermal plus non-thermal model; a multi-temperature thermal model without a non-thermal component cannot be ruled out. Furthermore, we do not see a spiky pulse profile in the hard X-ray band, as previously reported based on Suzaku observations. For other magnetars and rotation-powered pulsars observed with NuSTAR, data analysis results will be soon available. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

The Parkes Multibeam Pulsar Survey is a sensitive survey of a strip of the Galactic plane with |b| < 5° and 260° < l < 50° at 1374 MHz. Here we report the discovery of 120 new pulsars and subsequent timing observations, primarily using the 76-m Lovell radio telescope at Jodrell Bank. The main features of the sample of 370 published pulsars discovered during the multibeam survey are described. Furthermore, we highlight two pulsars: PSR J1734-3333, a young pulsar with the second highest surface magnetic field strength among the known radio pulsars, B[sub s]= 5.4 × 10[sup 13] G , and PSR J1830-1135, the second slowest radio pulsar known, with a 6-s period. [ABSTRACT FROM AUTHOR]

Examines the performance of Parkes multi-beam pulsar survey along the Galactic plane. Inclusion of the concept of receiver and data acquisition system; Emphasis of the pulsar emission properties; Consideration of high radio luminosity.

Examines the Parkes multi-beam pulsar survey. Use of a 13-beam receiver on the 64-m Parkes radio telescope; Nominal limiting flux density of the survey; Increase in radio luminosity of the pulsar.

We report on the discovery of a binary pulsar, PSR J1740-3052, during the Parkes multibeam survey. Timing observations of the 570-ms pulsar at Jodrell Bank and Parkes show that it is young, with a characteristic age of 350 kyr, and is in a 231-d, highly eccentric orbit with a companion whose mass exceeds 11 M[sub ⊙]. An accurate position for the pulsar was obtained using the Australia Telescope Compact Array. Near-infrared 2.2-μm observations made with the telescopes at the Siding Spring observatory reveal a late-type star coincident with the pulsar position. However, we do not believe that this star is the companion of the pulsar, because a typical star of this spectral type and required mass would extend beyond the orbit of the pulsar. Furthermore, the measured advance of periastron of the pulsar suggests a more compact companion, for example, a main-sequence star with radius only a few times that of the Sun. Such a companion is also more consistent with the small dispersion measure variations seen near periastron. Although we cannot conclusively rule out a black hole companion, we believe that the companion is probably an early B star, making the system similar to the binary PSR J0045-7319. [ABSTRACT FROM AUTHOR]

Timing observations of 40 mostly young pulsars using the ATNF Parkes radio telescope between 1990 January and 1998 December are reported. In total, 20 previously unreported glitches and 10 other glitches were detected in 11 pulsars. These included 12 glitches in PSR J1341-6220, corresponding to a glitch rate of 1.5 glitches per year. We also detected the largest known glitch, in PSR J1614-5047, with Δν[sub g]ν≈6.5×10[sup -6], where ν=1/P is the pulse frequency. Glitch parameters were determined both by extrapolating timing solutions to interglitch intervals and by phase-coherent timing fits across the glitch(es). These fits also give improved positions and dispersion measures for many of the pulsars. Analysis of glitch parameters, both from this work and from previously published results, shows that most glitches have a fractional amplitude Δν[sub g]ν of between 10[sup -8] and 10[sup -6]. There is no consistent relationship between glitch amplitude and the time since the previous glitch or the time to the following glitch, either for the ensemble or for individual pulsars. As previously recognized, the largest glitch activity is seen in pulsars with ages of order 10[sup 4] yr, but for about 30 per cent of such pulsars, no glitches were detected in the 8-year data span. There is some evidence for a new type of timing irregularity in which there is a significant increase in pulse frequency over a few days, accompanied by a decrease in the magnitude of the slow-down rate. Fits of an exponential recovery to post-glitch data show that for most older pulsars, only a small fraction of the glitch decays. In some younger pulsars a large fraction of the glitch decays, but in others there is very little decay. Apart from the Crab pulsar, there is no clear dependence of recovery time-scale on pulsar age. [ABSTRACT FROM AUTHOR]

We are undertaking a high-frequency survey of the Galactic plane for radio pulsars, using the 13-element multibeam receiver on the 64-m Parkes radio telescope. We describe briefly the survey system and some of the initial results. PSR J1811-1736, one of the first pulsars discovered with this system, has a rotation period of 104 ms. Subsequent timing observations using the 76-m radio telescope at Jodrell Bank show that it is in an 18.8-d, highly eccentric binary orbit. We have measured the rate of advance of periastron which indicates a total system mass of 2.6±0.9 M[sub ⊙], and the minimum companion mass is about 0.7 M[sub ⊙]. This, the high orbital eccentricity and the recycled nature of the pulsar suggest that this system is composed of two neutron stars, only the fourth or fifth such system known in the disc of the Galaxy. [ABSTRACT FROM AUTHOR]

Investigates magnetar-like x-ray bursts from an anomalous x-ray pulsar (AXP). Soft-gamma-ray (SGR) repeaters thought to be magnetars; Suggestion that AXPs might also be magnetars; Close relationship between AXPs and SGRs with both being magnetars.

Presents evidence from a precessing pulsar orbit for a neutron-star birth kick. Explanation of the high velocities of pulsars; Radio observations of the pulsar PSR J0045-7319; Significant deviations from a simple Keplerian orbit; Indications of a pulsar's periastron and spin-orbiting coupling seen through a misalignment; Explanation of the misalignment.