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The Parkes Multibeam Pulsar Survey -- II. Discovery and Timing of 120 Pulsars  [PDF]
D. J. Morris,G. Hobbs,A. G. Lyne,I. H. Stairs,F. Camilo,R. N. Manchester,A. Possenti,J. F. Bell,V. M. Kaspi,N. D'Amico,N. P. F. McKay,F. Crawford,M. Kramer
Physics , 2002, DOI: 10.1046/j.1365-8711.2002.05551.x
Abstract: The Parkes multibeam pulsar survey is a sensitive survey of a strip of the Galactic plane with $|b|<5\degr$ and $260\degr < l < 50\degr$ 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, $B_s = 5.4\times10^{13}$ G, and PSR J1830$-$1135, the second slowest radio pulsar known, with a 6-s period.
The Parkes multibeam pulsar survey: III. Young pulsars & the discovery and timing of 200 pulsars  [PDF]
M. Kramer,J. F. Bell,R. N. Manchester,A. G. Lyne,F. Camilo,I. H. Stairs,N. D'Amico,V. M. Kaspi,G. Hobbs,D. J. Morris,F. Crawford,A. Possenti,B. C. Joshi,M. A. McLaughlin,D. R. Lorimer,A. J. Faulkner
Physics , 2003, DOI: 10.1046/j.1365-8711.2003.06637.x
Abstract: The Parkes multibeam pulsar survey has unlocked vast areas of the Galactic plane which were previously invisible to earlier low-frequency and less-sensitive surveys. The survey has discovered more than 600 new pulsars so far, including many that are young and exotic. In this paper we report the discovery of 200 pulsars for which we present positional and spin-down parameters, dispersion measures, flux densities and pulse profiles. A large number of these new pulsars are young and energetic, and we review possible associations of $\gamma$-ray sources with the sample of about 1300 pulsars for which timing solutions are known. Based on a statistical analysis, we estimate that about $19\pm6$ associations are genuine. The survey has also discovered 12 pulsars with spin properties similar to those of the Vela pulsar, nearly doubling the known population of such neutron stars. Studying the properties of all known `Vela-like' pulsars, we find their radio luminosities to be similar to normal pulsars, implying that they are very inefficient radio sources. Finally, we review the use of the newly discovered pulsars as Galactic probes and discuss the implications of the new NE2001 Galactic electron density model for the determination of pulsar distances and luminosities.
The Pulsar Search Collaboratory: Discovery and Timing of Five New Pulsars  [PDF]
R. Rosen,J. Swiggum,M. A. McLaughlin,D. R. Lorimer,M. Yun,S. Heatherly,J. Boyles,R. Lynch,V. I. Kondratiev,S. Scoles,S. M. Ransom,M. L. Moniot,A. Cottrill,M. Weaver,A. Snider,C. Thompson,M. Raycraft,J. Dudenhoefer,L. Allphin,J. Thorley,B. Meadows,G. Marchiny,A. Liska,A. M. O'Dwyer,B. Butler,S. Bloxton,H. Mabry,H. Abate,J. Boothe,S. Pritt,J. Alberth,A. Green,R. J. Crowley,A. Agee,S. Nagley,N. Sargent,E. Hinson,K. Smith,R. McNeely,H. Quigley,A. Pennington,S. Chen,T. Maynard,L. Loope,N. Bielski,J. R. McGough,J. C. Gural,S. Colvin,S. Tso,Z. Ewen,M. Zhang,N. Ciccarella,B. Bukowski,C. B. Novotny,J. Gore,K. Sarver,S. Johnson,H. Cunningham,D. Collins,D. Gardner,A. Monteleone,J. Hall,R. Schweinhagen,J. Ayers,S. Jay,B. Uosseph,D. Dunkum,J. Pal,S. Dydiw,M. Sterling,E. Phan
Physics , 2012, DOI: 10.1088/0004-637X/768/1/85
Abstract: We present the discovery and timing solutions of five new pulsars by students involved in the Pulsar Search Collaboratory (PSC), a NSF-funded joint program between the National Radio Astronomy Observatory and West Virginia University designed to excite and engage high-school students in Science, Technology, Engineering, and Mathematics (STEM) and related fields. We encourage students to pursue STEM fields by apprenticing them within a professional scientific community doing cutting edge research, specifically by teaching them to search for pulsars. The students are analyzing 300 hours of drift-scan survey data taken with the Green Bank Telescope at 350 MHz. These data cover 2876 square degrees of the sky. Over the course of five years, more than 700 students have inspected diagnostic plots through a web-based graphical interface designed for this project. The five pulsars discovered in the data have spin periods ranging from 3.1 ms to 4.8 s. Among the new discoveries are - PSR J1926-1314, a long period, nulling pulsar; PSR J1821+0155, an isolated, partially recycled 33-ms pulsar; and PSR J1400-1438, a millisecond pulsar in a 9.5-day orbit whose companion is likely a white dwarf star.
A coherent acceleration search of the Parkes multi-beam pulsar survey - techniques and the discovery and timing of 16 pulsars  [PDF]
R. P. Eatough,M. Kramer,A. G. Lyne,M. J. Keith
Physics , 2013, DOI: 10.1093/mnras/stt161
Abstract: A fully coherent acceleration search algorithm has been applied to the Parkes multi- beam pulsar survey of the Galactic plane to search for previously undiscovered relativistic binary pulsars. The search has resulted in the discovery of 16 pulsars including a binary millisecond pulsar and an intermittent pulsar. Despite a number of promising candidates there have been no new discoveries of relativistic binary pulsars. Here we detail the acceleration search performed in our analysis and present coherent timing solutions for each of pulsars discovered. In light of the lack of discoveries of relativistic binary pulsars, we also discuss the technique of acceleration searching and its effectiveness in finding these systems.
The Parkes Multibeam Pulsar Survey: I. Observing and Data Analysis Systems, Discovery and Timing of 100 Pulsars  [PDF]
R. N. Manchester,A. G. Lyne,F. Camilo,J. F. Bell,V. M. Kaspi,N. D'Amico,N. P. F. McKay,F. Crawford,I. H. Stairs,A. Possenti,M. Kramer,D. C. Sheppard
Physics , 2001, DOI: 10.1046/j.1365-8711.2001.04751.x
Abstract: The Parkes multibeam pulsar survey is a sensitive survey of a strip along the Galactic plane with |b|<5 deg and l=260 deg to l=50 deg. It uses a 13-beam receiver on the 64-m Parkes radio telescope, receiving two polarisations per beam over a 288 MHz bandwidth centred on 1374 MHz. Receiver and data acquisition systems are described in some detail. For pulsar periods in the range 0.1 - 2 s and dispersion measures of less than 300 cm^{-3} pc, the nominal limiting flux density of the survey is about 0.2 mJy. At shorter or longer periods or higher dispersions, the sensitivity is reduced. Timing observations are carried out for pulsars discovered in the survey for 12 - 18 months after confirmation to obtain accurate positions, spin parameters, dispersion measures, pulse shapes and mean flux densities. The survey is proving to be extremely successful, with more than 600 pulsars discovered so far. We expect that, when complete, this one survey will come close to finding as many pulsars as all previous pulsar surveys put together. The newly discovered pulsars tend to be young, distant and of high radio luminosity. They will form a valuable sample for studies of pulsar emission properties, the Galactic distribution and evolution of pulsars, and as probes of interstellar medium properties. This paper reports the timing and pulse shape parameters for the first 100 pulsars timed at Parkes, including three pulsars with periods of less than 100 ms which are members of binary systems. These results are briefly compared with the parameters of the previously known population.
The High Time Resolution Universe Pulsar Survey X: Discovery of four millisecond pulsars and updated timing solutions of a further 12  [PDF]
C. Ng,M. Bailes,S. D. Bates,N. D. R. Bhat,M. Burgay,S. Burke-Spolaor,D. J. Champion,P. Coster,S. Johnston,M. J. Keith,M. Kramer,L. Levin,E. Petroff,A. Possenti,B. W. Stappers,W. van Straten,D. Thornton,C. Tiburzi,C. G. Bassa,P. C. C. Freire,L. Guillemot,A. G. Lyne,T. M. Tauris,R. M. Shannon,N. Wex
Physics , 2014, DOI: 10.1093/mnras/stu067
Abstract: We report on the discovery of four millisecond pulsars (MSPs) in the High Time Resolution Universe (HTRU) pulsar survey being conducted at the Parkes 64-m radio telescope. All four MSPs are in binary systems and are likely to have white dwarf companions. In addition, we present updated timing solutions for 12 previously published HTRU MSPs, revealing new observational parameters such as five proper motion measurements and significant temporal dispersion measure variations in PSR J1017-7156. We discuss the case of PSR J1801-3210, which shows no significant period derivative after four years of timing data. Our best-fit solution shows a period derivative of the order of $10^{-23}$, an extremely small number compared to that of a typical MSP. However, it is likely that the pulsar lies beyond the Galactic Centre, and an unremarkable intrinsic period derivative is reduced to close to zero by the Galactic potential acceleration. Furthermore, we highlight the potential to employ PSR J1801-3210 in the strong equivalence principle test due to its wide and circular orbit. In a broader comparison with the known MSP population, we suggest a correlation between higher mass functions and the presence of eclipses in `very low-mass binary pulsars', implying that eclipses are observed in systems with high orbital inclinations. We also suggest that the distribution of the total mass of binary systems is inversely-related to the Galactic height distribution. Finally, we report on the first detection of PSRs J1543-5149 and J1811-2404 as gamma-ray pulsars.
The timing behaviour of radio pulsars  [PDF]
G. Hobbs
Physics , 2009,
Abstract: The purpose of this review paper is to summarise the pulsar timing method, to provide an overview of recent research into the spin-down of pulsars over decadal timescales and to highlight the science that can be achieved using high-precision timing of millisecond pulsars.
Timing the Parkes Multibeam Pulsars  [PDF]
R. N. Manchester,A. G. Lyne,F. Camilo,V. M. Kaspi,I. H. Stairs,F. Crawford,D. J. Morris,J. F. Bell,N. D'Amico
Physics , 1999,
Abstract: Measurement of accurate positions, pulse periods and period derivatives is an essential follow-up to any pulsar survey. The procedures being used to obtain timing parameters for the pulsars discovered in the Parkes multibeam pulsar survey are described. Completed solutions have been obtained so far for about 80 pulsars. They show that the survey is preferentially finding pulsars with higher than average surface dipole magnetic fields. Eight pulsars have been shown to be members of binary systems and some of the more interesting results relating to these are presented.
An analysis of the timing irregularities for 366 pulsars  [PDF]
G. Hobbs,A. G. Lyne,M. Kramer
Physics , 2009, DOI: 10.1111/j.1365-2966.2009.15938.x
Abstract: We provide an analysis of timing irregularities observed for 366 pulsars. Observations were obtained using the 76-m Lovell radio telescope at the Jodrell Bank Observatory over the past 36 years. These data sets have allowed us to carry out the first large-scale analysis of pulsar timing noise over time scales of > 10yr, with multiple observing frequencies and for a large sample of pulsars. Our sample includes both normal and recycled pulsars. The timing residuals for the pulsars with the smallest characteristic ages are shown to be dominated by the recovery from glitch events, whereas the timing irregularities seen for older pulsars are quasi-periodic. We emphasise that previous models that explained timing residuals as a low-frequency noise process are not consistent with observation.
Timing of five millisecond pulsars discovered in the PALFA survey  [PDF]
P. Scholz,V. M. Kaspi,A. G. Lyne,B. W. Stappers,S. Bogdanov,J. M. Cordes,F. Crawford,R. D. Ferdman,P. C. C. Freire,J. W. T. Hessels,D. R. Lorimer,I. H. Stairs,B. Allen,A. Brazier,F. Camilo,R. F. Cardoso,S. Chatterjee,J. S. Deneva,F. A. Jenet,C. Karako-Argaman,B. Knispel,P. Lazarus,K. J. Lee,J. van Leeuwen,R. Lynch,E. C. Madsen,M. A. McLaughlin,S. M. Ransom,X. Siemens,L. G. Spitler,K. Stovall,J. K. Swiggum,A. Venkataraman,W. W. Zhu
Physics , 2015, DOI: 10.1088/0004-637X/800/2/123
Abstract: We present the discovery of five millisecond pulsars (MSPs) from the PALFA Galactic plane survey using Arecibo. Four of these (PSRs J0557+1551, J1850+0244, J1902+0300, and J1943+2210) are binary pulsars whose companions are likely white dwarfs, and one (PSR J1905+0453) is isolated. Phase-coherent timing solutions, ranging from $\sim$1 to $\sim$3 years in length, and based on observations from the Jodrell Bank and Arecibo telescopes, provide precise determinations of spin, orbital, and astrometric parameters. All five pulsars have large dispersion measures ($>100$ pc cm$^{-3}$, within the top 20% of all known Galactic field MSPs) and are faint (1.4 GHz flux density < 0.1 mJy, within the faintest 5% of all known Galactic field MSPs), illustrating PALFA's ability to find increasingly faint, distant MSPs in the Galactic plane. In particular, PSR J1850+0244 has a dispersion measure of 540 pc cm$^{-3}$, the highest of all known MSPs. Such distant, faint MSPs are important input for accurately modeling the total Galactic MSP population.
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