Phase-resolved Faraday rotation in pulsars
We have detected significant Rotation Measure variations for 9 bright pulsars, as a function of pulse longitude. An additional sample of 10 pulsars showed a rather constant RM with phase, yet a small degree of RM fluctuation is visible in at least 3 of those cases. In all cases, we have found that t...
| Main Authors: | , , , , |
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| Format: | Journal article |
| Published: |
2009
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| _version_ | 1797080120896258048 |
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| author | Noutsos, A Karastergiou, A Kramer, M Johnston, S Stappers, B |
| author_facet | Noutsos, A Karastergiou, A Kramer, M Johnston, S Stappers, B |
| author_sort | Noutsos, A |
| collection | OXFORD |
| description | We have detected significant Rotation Measure variations for 9 bright pulsars, as a function of pulse longitude. An additional sample of 10 pulsars showed a rather constant RM with phase, yet a small degree of RM fluctuation is visible in at least 3 of those cases. In all cases, we have found that the rotation of the polarization position angle across our 1.4 GHz observing band is consistent with the wavelength-squared law of interstellar Faraday Rotation. We provide for the first time convincing evidence that RM variations across the pulse are largely due to interstellar scattering, although we cannot exclude that magnetospheric Faraday Rotation may still have a minor contribution; alternative explanations of this phenomenon, like erroneous de-dispersion and the presence of non-orthogonal polarization modes, are excluded. If the observed, phase-resolved RM variations are common amongst pulsars, then many of the previously measured pulsar RMs may be in error by as much as a few tens of rad m-2. |
| first_indexed | 2024-03-07T00:55:38Z |
| format | Journal article |
| id | oxford-uuid:87fab9a2-7c30-43e5-a251-65a3d30510ae |
| institution | University of Oxford |
| last_indexed | 2024-03-07T00:55:38Z |
| publishDate | 2009 |
| record_format | dspace |
| spelling | oxford-uuid:87fab9a2-7c30-43e5-a251-65a3d30510ae2022-03-26T22:14:00ZPhase-resolved Faraday rotation in pulsarsJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:87fab9a2-7c30-43e5-a251-65a3d30510aeSymplectic Elements at Oxford2009Noutsos, AKarastergiou, AKramer, MJohnston, SStappers, BWe have detected significant Rotation Measure variations for 9 bright pulsars, as a function of pulse longitude. An additional sample of 10 pulsars showed a rather constant RM with phase, yet a small degree of RM fluctuation is visible in at least 3 of those cases. In all cases, we have found that the rotation of the polarization position angle across our 1.4 GHz observing band is consistent with the wavelength-squared law of interstellar Faraday Rotation. We provide for the first time convincing evidence that RM variations across the pulse are largely due to interstellar scattering, although we cannot exclude that magnetospheric Faraday Rotation may still have a minor contribution; alternative explanations of this phenomenon, like erroneous de-dispersion and the presence of non-orthogonal polarization modes, are excluded. If the observed, phase-resolved RM variations are common amongst pulsars, then many of the previously measured pulsar RMs may be in error by as much as a few tens of rad m-2. |
| spellingShingle | Noutsos, A Karastergiou, A Kramer, M Johnston, S Stappers, B Phase-resolved Faraday rotation in pulsars |
| title | Phase-resolved Faraday rotation in pulsars |
| title_full | Phase-resolved Faraday rotation in pulsars |
| title_fullStr | Phase-resolved Faraday rotation in pulsars |
| title_full_unstemmed | Phase-resolved Faraday rotation in pulsars |
| title_short | Phase-resolved Faraday rotation in pulsars |
| title_sort | phase resolved faraday rotation in pulsars |
| work_keys_str_mv | AT noutsosa phaseresolvedfaradayrotationinpulsars AT karastergioua phaseresolvedfaradayrotationinpulsars AT kramerm phaseresolvedfaradayrotationinpulsars AT johnstons phaseresolvedfaradayrotationinpulsars AT stappersb phaseresolvedfaradayrotationinpulsars |