High cadence pulsar timing with CHIME/Pulsar
department or school: Science, Faculty of
department or school: Physics and Astronomy, Department of
data provider: DSpace
degree campus: UBCV
creator: Cassity, Alyssa
issued: 2025-02-11T09:01:46Z
issued: 2025
related degree: Master of Science - MSc
degree grantor: University of British Columbia
description: Pulsars are rapidly rotating, highly magnetized neutron starsâthe collapsed remnants of massive stars following a supernova explosion. They produce beams of radiation that reach our observatories on Earth at regular intervals. The precise timing of these radio pulses has many applications, including exploring fundamental physics, testing the predictions of general relativity, probing the interstellar medium, and even detecting gravitational waves. This work investigates variability in pulsar emission using the unprecedented observing cadence of the CHIME telescope. The Canadian Hydrogen Intensity Mapping Experiment (CHIME) is a radio telescope near Penticton, British Columbia, Canada. Although initially conceived as a cosmology experiment, it has proven to be an excellent instrument for discovering and studying radio transients. This thesis utilizes the CHIME/Pulsar science backend. First, for PSR B0540+23 we conduct an analysis to explore emission modulation during periods of low solar elongation, which occur once a year. Each year, the pulsar is occulted by the solar wind due to its position in the sky. We observe dispersion measure variations caused by excess solar wind electrons along the line of sight and infer a solar electron density based on these observations. Next, we study nulling and mode-changing behavior in PSRs B0809+74 and B0329+54. We employ a matched filtering pipeline to identify this behavior. We investigate links between these phenomena and an excess of outlier TOAs identified by the NANOGrav Collaborationâs outlier analysis. We find that the outlier analysis is sensitive to mode-changing in PSR B0329+54. These findings highlight the utility of CHIME/Pulsarâs daily observing cadence for studying pulsar emission. With the capabilities of CHIME/Pulsar, we are able to identify yearly occultations of PSR B0540+23 by the solar wind. We also provide a foundation for applying the NANOGrav outlier analysis to identify mode-changing in pulsars. The resul…
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/90354
note: High Cadence Pulsar Timing withCHIME/PulsarbyAlyssa CassityB.A., Smith College, 2020A THESIS SUBMITTED IN PARTIAL FULFILLMENT OFTHE REQUIREMENTS FOR THE DEGREE OFMASTER OF SCIENCEinThe Faculty of Graduate and Postdoctoral Studies(Astronomy)THE UNIVERSITY OF BRITISH COLUMBIA(Vancouver)February 2025© Alyssa Cassity 2025The following individuals certify that they have read, and recommend tothe Faculty of Graduate and Postdoctoral Studies for acceptance, the thesisentitled:submitted by in partial fulfillment of the requirements forthe degree ofinExamining Committee:SupervisorSupervisory Committee MemberiiAlyssa CassityMaster of ScienceAstronomyHigh cadence pulsar timing with CHIME/PulsarIngrid Stairs, Professor, Physics and Astronomy, UBCJeremy Heyl, Professor, Physics and Astronomy, UBCAbstractPulsars are rapidly rotating, highly magnetized neutron starsâthe collapsedremnants of massive stars following a supernova explosion. They producebeams of radiation that reach our observatories on Earth at regular intervals.The precise timing of these radio pulses has many applications, includingexploring fundamental physics, testing the predictions of general relativity,probing the interstellar medium, and even detecting gravitational waves.This work investigates variability in pulsar emission using the unprecedentedobserving cadence of the CHIME telescope.The Canadian Hydrogen Intensity Mapping Experiment (CHIME) is aradio telescope near Penticton, British Columbia, Canada. Although ini-tially conceived as a cosmology experiment, it has proven to be an excellentinstrument for discovering and studying radio transients. This thesis utilizesthe CHIME/Pulsar science backend.First, for PSR B0540+23 we conduct an analysis to explore emissionmodulation during periods of low solar elongation, which occur once a year.Each year, the pulsar is occulted by the solar wind due to its position in thesky. We observe dispersion measure variations caused by excess solar windelectrons along the …
has type: Thesis/Dissertation
date issued: 2025-05
is shown at: 10.14288/1.0448046
language: eng
degree discipline: Astronomy
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-NoDerivatives 4.0 International
rights URI: http://creativecommons.org/licenses/by-nc-nd/4.0/
scholar level: Graduate
contributor: Stairs, Ingrid Helen, 1972-
type: Text
identifier URI: http://hdl.handle.net/2429/90354