Single Pulse Dispersion Measure of the Crab Pulsar
Abstract

We investigate the use of bright single pulses from the Crab pulsar to determine separately the dispersion measure (DM) for the Main Pulse and Interpulse components. We develop two approaches using cross-correlation functions (CCFs). The first method computes the CCF of the total intensity of each of the 64 frequency channels with a reference channel and converts the time lag of maximum correlation into a DM. The second method separately computes the CCF between every pair of channels for each individual bright pulse and extracts an average DM from the distribution of all channel-pair DMs. Both methods allow the determination of the DM with a relative uncertainty of better than 10−5and provide robust estimates for the uncertainty of the best-fit value. We find differences in DM between the Main Pulse, the Low Frequency Interpulse, and the High Frequency Interpulse using both methods in a frequency range from 4 to 6 GHz. Earlier observations of the High Frequency Interpulse carried out by Hankins et al. (2016) resulted in DMHFIP–DMMPof 0.010 ± 0.016 pc cm−3. Our results indicate a DMHFIP–DMMPof 0.0127 ± 0.0011 pc cm−3(with DMcompbeing the DM value of the respective emission component), confirming earlier results with an independent method. more »

Authors:
; ; ; ;
Publication Date:
NSF-PAR ID:
10369820
Journal Name:
The Astrophysical Journal
Volume:
935
Issue:
2
Page Range or eLocation-ID:
Article No. 84
ISSN:
0004-637X
Publisher:
DOI PREFIX: 10.3847
National Science Foundation
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2. Abstract

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3. ABSTRACT

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4. Abstract

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5. Abstract

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