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Abstract We develop a new method for studying the Galactic magnetic field along the spiral arms using pulsar Faraday rotation measures (RMs). Our new technique accounts for the dot-product nature of Faraday rotation and also splits the associated path integral into segments corresponding to particular zones along the line of sight. We apply this geometrically corrected, arm-by-arm technique to the low-latitude portion of a recently published set of Arecibo Faraday RMs for 313 pulsars, along with previously obtained RMs in the same regions. We find disparities >1σbetween the magnitude of the field above and below the plane in the Local Arm, Sagittarius Arm, Sagittarius-to-Scutum Interarm, Scutum Arm, and Perseus Arm. We find evidence for a single field reversal near the Local Arm–Sagittarius Arm boundary. Interestingly, our results suggest that this field reversal is dependent on latitude, occurring inside the Sagittarius Arm at negative Galactic latitudes and at the Local Arm–Sagittarius Arm boundary at positive Galactic latitudes. We discuss all of our results in the context of different models and other observational Galactic magnetic field analyses.
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Pulsar-based map of galactic acceleration
Binary pulsars can be used to probe Galactic potential gradients through calculating their line-of-sight accelerations. We present the first data release of direct line-of-sight acceleration measurements for 29 binary pulsars. We validate these data with a local acceleration model, and compare our results to those from earlier works. We find evidence for an acceleration gradient in agreement with these values, with our results indicating a local disk density of 0.040+0.020−0.020 M_solar / pc^3. We also find evidence for unmodeled noise of unknown origin in our dataset.
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- PAR ID:
- 10530511
- Publisher / Repository:
- Physical Review D
- Date Published:
- Journal Name:
- Physical Review D
- Volume:
- 109
- Issue:
- 12
- ISSN:
- 2470-0010
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1103/PhysRevD.109.123015
