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- Pulsar_timing_array abstract "A pulsar timing array is a set of millisecond pulsars that can be used to detect and analyse gravitational waves. Such a detection would result from a detailed investigation of the arrival times of pulses emitted by these millisecond pulsars.Millisecond pulsars are used because they appear not to be prone to the starquakes and accretion events which can affect the period of classical pulsars.The most interesting influence on these propagation properties is low-frequency gravitational waves, with a frequency of 10−9 to 10−6 Hertz; the expected astrophysical sources of such gravitational waves are massive black hole binaries in the centres of merging galaxies, where tens of millions of solar masses are in orbit with a period between months and a few years.The gravitational waves cause the time of arrival of the pulses to vary by a few tens of nanoseconds over their wavelength (so, for a frequency of 3 x 10 −8 Hz, one cycle per year, you would find that pulses arrive 20 ns early in July and 20 ns late in January). This is an extremely delicate experiment, although millisecond pulsars are stable enough clocks that the time of arrival of the pulses can be predicted to the required accuracy; the experiments use collections of 20 to 50 pulsars to account for dispersion effects in the atmosphere and in the space between us and the pulsar. It is necessary to monitor each pulsar roughly once a week; a higher cadence of observation would allow the detection of higher-frequency gravitational waves, but it is unclear whether there would be loud enough astrophysical sources at such frequencies.It is not possible to get particularly accurate sky locations for the sources by this method - analysing timings for twenty pulsars would produce a region of uncertainty of 100 square degrees, a patch of sky about the size of the constellation Scutum which would contain at least thousands of merging galaxies.".
- Pulsar_timing_array wikiPageExternalLink 0911.5206.
- Pulsar_timing_array wikiPageExternalLink 084013.
- Pulsar_timing_array wikiPageExternalLink nanograv.org.
- Pulsar_timing_array wikiPageExternalLink ppta.
- Pulsar_timing_array wikiPageExternalLink www.epta.eu.org.
- Pulsar_timing_array wikiPageExternalLink simpta.
- Pulsar_timing_array wikiPageID "26422187".
- Pulsar_timing_array wikiPageRevisionID "599986775".
- Pulsar_timing_array hasPhotoCollection Pulsar_timing_array.
- Pulsar_timing_array subject Category:Gravitation.
- Pulsar_timing_array comment "A pulsar timing array is a set of millisecond pulsars that can be used to detect and analyse gravitational waves.".
- Pulsar_timing_array label "Pulsar timing array".
- Pulsar_timing_array sameAs m.0bbx54v.
- Pulsar_timing_array sameAs Q7259618.
- Pulsar_timing_array sameAs Q7259618.
- Pulsar_timing_array wasDerivedFrom Pulsar_timing_array?oldid=599986775.
- Pulsar_timing_array isPrimaryTopicOf Pulsar_timing_array.