A LOFAR census of millisecond pulsars

Kondratiev, VI; Verbiest, JPW; Hessels, JWT; Bilous, AV; Stappers, BW; Kramer, M; Keane, EF; Noutsos, A; Osłowski, S; Breton, RP; Hassall, TE; Alexov, A; Cooper, S; Falcke, H; Grießmeier, JM; Karastergiou, A; Kuniyoshi, M; Pilia, M; Sobey, C; Ter Veen, S; Van Leeuwen, J; Weltevrede, P; Bell, ME; Broderick, JW; Corbel, S; Eisloffel, J; Markoff, S; Rowlinson, A; Swinbank, JD; Wijers, RAMJ; Wijnands, R; Zarka, P

A LOFAR census of millisecond pulsars

Kondratiev, VI Verbiest, JPW Hessels, JWT Bilous, AV Stappers, BW Kramer, M Keane, EF Noutsos, A Osłowski, S Breton, RP Hassall, TE Alexov, A Cooper, S Falcke, H Grießmeier, JM Karastergiou, A Kuniyoshi, M Pilia, M Sobey, C Ter Veen, S Van Leeuwen, J Weltevrede, P Bell, ME

Broderick, JW Corbel, S Eisloffel, J Markoff, S Rowlinson, A Swinbank, JD Wijers, RAMJ Wijnands, R Zarka, P

Permalink

Publication Type:: Journal Article
Citation:: Astronomy and Astrophysics, 2016, 585
Issue Date:: 2016-01-01

Open Access

Copyright Clearance Process

Recently Added
In Progress
Open Access

This item is open access.

Adobe PDF

Download Published VersionAdobe PDF (2.05 MB)

View on publisher's site

View statistics

Full metadata record

Field	Value	Language
dc.contributor.author	Kondratiev, VI	en_US
dc.contributor.author	Verbiest, JPW	en_US
dc.contributor.author	Hessels, JWT	en_US
dc.contributor.author	Bilous, AV	en_US
dc.contributor.author	Stappers, BW	en_US
dc.contributor.author	Kramer, M	en_US
dc.contributor.author	Keane, EF	en_US
dc.contributor.author	Noutsos, A	en_US
dc.contributor.author	Osłowski, S	en_US
dc.contributor.author	Breton, RP	en_US
dc.contributor.author	Hassall, TE	en_US
dc.contributor.author	Alexov, A	en_US
dc.contributor.author	Cooper, S	en_US
dc.contributor.author	Falcke, H	en_US
dc.contributor.author	Grießmeier, JM	en_US
dc.contributor.author	Karastergiou, A	en_US
dc.contributor.author	Kuniyoshi, M	en_US
dc.contributor.author	Pilia, M	en_US
dc.contributor.author	Sobey, C	en_US
dc.contributor.author	Ter Veen, S	en_US
dc.contributor.author	Van Leeuwen, J	en_US
dc.contributor.author	Weltevrede, P	en_US
dc.contributor.author	Bell, ME https://orcid.org/0000-0003-1767-5277	en_US
dc.contributor.author	Broderick, JW	en_US
dc.contributor.author	Corbel, S	en_US
dc.contributor.author	Eisloffel, J	en_US
dc.contributor.author	Markoff, S	en_US
dc.contributor.author	Rowlinson, A	en_US
dc.contributor.author	Swinbank, JD	en_US
dc.contributor.author	Wijers, RAMJ	en_US
dc.contributor.author	Wijnands, R	en_US
dc.contributor.author	Zarka, P	en_US
dc.date.issued	2016-01-01	en_US
dc.identifier.citation	Astronomy and Astrophysics, 2016, 585	en_US
dc.identifier.issn	0004-6361	en_US
dc.identifier.uri	http://hdl.handle.net/10453/113567
dc.description.abstract	© 2016 ESO. We report the detection of 48 millisecond pulsars (MSPs) out of 75 observed thus far using the LOw-Frequency ARray (LOFAR) in the frequency range 110-188 MHz. We have also detected three MSPs out of nine observed in the frequency range 38-77 MHz. This is the largest sample of MSPs ever observed at these low frequencies, and half of the detected MSPs were observed for the first time atfrequencies below 200 MHz. We present the average pulse profiles of the detected MSPs, their effective pulse widths, and flux densities and compare these with higher observing frequencies. The flux-calibrated, multifrequency LOFAR pulse profiles are publicly available via the European Pulsar Network Database of Pulsar Profiles. We also present average values of dispersion measures (DM) and discuss DM and profile variations. About 35% of the MSPs show strong narrow profiles, another 25% exhibit scattered profiles, and the rest are only weakly detected. A qualitative comparison of the LOFAR MSP profiles with those at higher radio frequencies shows constant separation between profile components. Similarly, the profile widths are consistent with those observed at higher frequencies, unless scattering dominates at the lowest frequencies. This is very different from what is observed for normal pulsars and suggests a compact emission region in the MSP magnetosphere. The amplitude ratio of the profile components, on the other hand, can dramatically change towards low frequencies, often with the trailing component becoming dominant. As previously demonstrated this can be caused by aberration and retardation. This data set enables high-precision studies of pulse profile evolution with frequency, dispersion, Faraday rotation, and scattering in the interstellar medium. Characterising and correcting these systematic effects may improve pulsar-timing precision at higher observing frequencies, where pulsar timing array projects aim to directly detect gravitational waves.	en_US
dc.relation.ispartof	Astronomy and Astrophysics	en_US
dc.relation.isbasedon	10.1051/0004-6361/201527178	en_US
dc.subject.classification	Astronomy & Astrophysics	en_US
dc.title	A LOFAR census of millisecond pulsars	en_US
dc.type	Journal Article
utslib.citation.volume	585	en_US
utslib.for	0201 Astronomical and Space Sciences	en_US
pubs.embargo.period	Not known	en_US
pubs.organisational-group	/University of Technology Sydney
pubs.organisational-group	/University of Technology Sydney/Faculty of Science
pubs.organisational-group	/University of Technology Sydney/Faculty of Science/School of Mathematical and Physical Sciences
utslib.copyright.status	open_access
pubs.publication-status	Published	en_US
pubs.volume	585	en_US

Abstract:

© 2016 ESO. We report the detection of 48 millisecond pulsars (MSPs) out of 75 observed thus far using the LOw-Frequency ARray (LOFAR) in the frequency range 110-188 MHz. We have also detected three MSPs out of nine observed in the frequency range 38-77 MHz. This is the largest sample of MSPs ever observed at these low frequencies, and half of the detected MSPs were observed for the first time atfrequencies below 200 MHz. We present the average pulse profiles of the detected MSPs, their effective pulse widths, and flux densities and compare these with higher observing frequencies. The flux-calibrated, multifrequency LOFAR pulse profiles are publicly available via the European Pulsar Network Database of Pulsar Profiles. We also present average values of dispersion measures (DM) and discuss DM and profile variations. About 35% of the MSPs show strong narrow profiles, another 25% exhibit scattered profiles, and the rest are only weakly detected. A qualitative comparison of the LOFAR MSP profiles with those at higher radio frequencies shows constant separation between profile components. Similarly, the profile widths are consistent with those observed at higher frequencies, unless scattering dominates at the lowest frequencies. This is very different from what is observed for normal pulsars and suggests a compact emission region in the MSP magnetosphere. The amplitude ratio of the profile components, on the other hand, can dramatically change towards low frequencies, often with the trailing component becoming dominant. As previously demonstrated this can be caused by aberration and retardation. This data set enables high-precision studies of pulse profile evolution with frequency, dispersion, Faraday rotation, and scattering in the interstellar medium. Characterising and correcting these systematic effects may improve pulsar-timing precision at higher observing frequencies, where pulsar timing array projects aim to directly detect gravitational waves.

Please use this identifier to cite or link to this item:

http://hdl.handle.net/10453/113567