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Pulsar J0453+1559, the 10Th Double Neutron Star System in the Universe

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Pulsar J0453+1559, the 10Th Double Neutron Star System in the Universe University of Texas Rio Grande Valley ScholarWorks @ UTRGV UTB/UTPA Electronic Theses and Dissertations Legacy Institution Collections 11-2014 Pulsar J0453+1559, the 10th double neutron star system in the universe Jose Guadalupe Martinez The University of Texas Rio Grande Valley Follow this and additional works at: https://scholarworks.utrgv.edu/leg_etd Part of the Cosmology, Relativity, and Gravity Commons, Physical Processes Commons, and the Stars, Interstellar Medium and the Galaxy Commons Recommended Citation Martinez, Jose Guadalupe, "Pulsar J0453+1559, the 10th double neutron star system in the universe" (2014). UTB/UTPA Electronic Theses and Dissertations. 52. https://scholarworks.utrgv.edu/leg_etd/52 This Thesis is brought to you for free and open access by the Legacy Institution Collections at ScholarWorks @ UTRGV. It has been accepted for inclusion in UTB/UTPA Electronic Theses and Dissertations by an authorized administrator of ScholarWorks @ UTRGV. For more information, please contact [email protected], [email protected]. Pulsar J0453+1559, the 10th Double Neutron Star System in the Universe By Jose Guadalupe Martinez A Thesis Presented to the Graduate Faculty of the College of Science, Mathematics and Technology in Partial Fulfillment of the Requirements for the Degree of Master of Science in the field of Physics November 2014 c Copyright by Jose Guadalupe Martinez November 2014 All Rights Reserved. Glossary of Abbreviations and Symbols DNS Double Neutron Star PSR Pulsar TOA’s Time of Arrival’s ARCC Arecibo Remote Command Center AO Arecibo Observatory Hz Hertz K Kelvin Jy Jansky G Gauss M⊙ Solar Mass P Period Pb Orbital Period x Semi-Major Axis e Eccentricity MT Total Mass Mp Pulsar Mass Mc Companion Mass iii ABSTRACT Pulsars are neutron stars that spin rapidly, are highly magnetized, and they emit beams of electromagnetic radiation like a lighthouse out in space. These beams of radiation are only observed when the beams face towards Earth and can be measured by a radio telescope. Pulsar studies have an abundance of scientific implementations in solid state physics, general relativity, galactic astronomy, astronomy, planetary physics and have even opened windows in cosmology. This thesis reports the results of a study of pulsar (PSR) J0453+1559, a new binary pulsar discovered in the Arecibo All-Sky 327 MegaHertz Drift Pulsar Survey. The recorded observations of the times of arrivals of the pulses of the pulsar in the system, J0453+1559, span a period of about 320 days, which allowed precise measurement of its spin period (45.7 ms) and its derivative (1.85 ± 0.13 × 10−19 ss−1). From these measurements we derived the characteristic age of the system as ∼ 3.9 × 106 years and having a magnetic field of ∼ 2.9 × 109 G. These measurements point out that this pulsar was mildly recycled by gradual accumulation of matter from the companion star. The cyclic dance of this system has an eccentric (e = 0.11) 4.07-day orbit. This eccentricity enables a highly significant quantification of the rate of advance of periastron asω ˙ = 0.0379 ± 0.0005 ◦yr−1, which entails the total mass of the system as M = 2.73 ± 0.006 M⊙. We also discovered the Shapiro delay, which allows an approximation of the individual masses being mp = 1.54 ± 0.006 M⊙ and mc = 1.19 ± 0.011 M⊙, appropriately. These masses, along with the orbital eccentricity, propose that PSR iv J0453+1559 is a double neutron star system with a mass asymmetry. The anticipated coalescence time due to the outflow of gravitational waves is ∼1.4 x 1012, approximately 100 times greater than the age of the Universe. This is the 10th recognized double neutron star system in the known Universe, and below is its story. v Para mi familia, Thank you for always being there and believing in me, I wouldn’t be here today without your advise, support, and your never-ending love. I love you all so much! vi ACKNOWLEDGMENTS I would like to thank Dr. Fredrick Jenet for his invaluable assistance and insights leading to the writing of this work. I thank the Department of Physics & Astronomy at the University of Texas at Brownsville for providing the setting and support that allowed this work to be done. Without the ARCC Scholars program none of this work could have been possible. I am truly grateful for being part of this incredible program and like to truly thank everyone from ARCC Executive Committee, faculty, staff, and students. vii TABLE OF CONTENTS Permission ...................................... i Approval ....................................... ii Copyright ...................................... iii Approval ....................................... iv Abstract ....................................... v Dedication ...................................... vi Acknowledgments ................................. vii List of Tables .................................... viii List of Figures ................................... ix 1 Introduction ................................... 1 1.1 PulsarBackground ............................. 1 1.2 DoubleNeutronStarSystems ....................... 6 1.3 TheLighthouseModel ........................... 7 1.4 Pulsarspinevolution ............................ 8 1.5 CharacteristicAge ............................. 10 1.6 MagneticFieldStrength .......................... 10 1.7 PulseDispersion .............................. 11 1.8 PulsarPopulation.............................. 12 2 Pulsar Timing ................................. 14 viii 2.1 Measuringpulsearrivaltimes . 15 2.2 AreciboAll-Sky327MHzDriftPulsarSurvey . 27 2.3 InitialObservationsofaNewPulsar . 28 2.4 SolvingDoubleNeutronStarSystemOrbit . .. 33 2.5 MassFunction................................ 35 2.6 ShapiroDelay................................ 40 2.7 Post-Keplerian Parameters and Relativistic Parameters......... 43 3 Results of J0453+1559 ............................ 45 3.1 abstract ................................... 46 3.2 Introduction................................. 46 3.3 Observationsanddatareduction. .. 48 ix LIST OF TABLES 1 DoubleNeutronStarSystemsknownintheUniverse . .. 8 2 DoubleNeutronStarSystemsknownintheUniverse . .. 48 3 TimingsolutionsforPSRJ0453+1559. .. 50 x LIST OF FIGURES 1 This is the lighthouse model for a rotating neutron star and its magnetosphere. 13 2 A pulsar’s pulses observed at higher frequencies arrive earlier at the telescope thantheirlowerfrequencycounterparts. .... 16 3 Diagram showing the basic concept of a pulsar timing observation. .... 17 4 This figure illustrates the technique of folding. This figure is taken from the Pulsar Search Collaboratory pulsar searching guide. ....... 18 5 Pulsar timing plot examples. In (a) is an example of a good timing solution with no unmodeled effects. In (b) is an example of an error in the frequency derivative. In (c) it shows a sinusoidal ripple that tells us there is an error in position. In (d) it shows that you did not model the pulsar propermotion. 21 6 A prepfold plot of pulsar J0154+18, a millisecond pulsar discovered in the AreciboAll-Sky327MHzDriftPulsarSurvey. 25 7 (a) Shows a time series for pulsar J0137+1654 folded at an incorrect period. Notice how the pulse is smeared and has a lower strength detection. (b) The same time series, but folded at the correct period, giving a sharper pulse signalwithastrongerdetection. 29 8 This is the discovery prepfold plot of pulsar J0453+1559, discovered in the AreciboAll-Sky327MHzDriftPulsarSurvey. 31 9 This is the confirmation prepfold plot of pulsar J0453+1559, this strong de- tection confirmed that PSR J0453+1559 is in fact a real pulsar....... 32 xi 10 Barycentric period measurements of PSR J0453+1559 vs time. The black dots denote observations and the red curve shows the expected change in observed period due to eccentric orbital motion for the best fitorbit. 36 11 This plot was created by the online Digital Sky Survey, NASA Infrared Sci- ence Archive which shows no optical companion near pulsar J0453+1559 within5arcminutes. .............................. 39 41 13 This plot shows the timing residuals versus its orbital phase of the binary system in which pulsar J0453+1559 is in. The top graph shows the detection of the Shapiro Delay which enables to constrain and measure precise mass measurements of the total mass and companion mass of the system. ... 42 15 PSRJ0453+1559Timingsolution. 51 xii CHAPTER 1 INTRODUCTION 1.1 PULSAR BACKGROUND Pulsars are rapidly rotating radio objects in the sky that are extremely magnetized, and weigh more than our sun but are only about 10km in diameter, see Figure 1. The formation of neutron stars occurs when stars with a high mass range of 8-20 M⊙ go su- pernovae and leave behind compact and highly magnetized cores. The violent outburst of a supernova blows off the outer layers of a star and creates an alluring supernova rem- nant. The core of the star then crumples under its own gravity, so protons and electrons fuse under gravity to form neutrons, consequently giving it the name “neutron star”. These particularly condensed objects emit beams of radiation that streak across the sky like light beams from a lighthouse. The term “lighthouse model” is used to describe the underlying idea of the pulsar phenomenon. As the neutron star swiftly rotates, charged particles are accelerated out along the magnetic field lines in the magnetosphere, see Figure 1. This acceleration causes the particles to emit electromagnetic radiation. This radiation is detected on Earth at radio frequencies as a series of observed pulses gen- erated as the magnetic axis of the pulsar, and
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