Gravitational Wave Astrophysics with Pulsar Timing Arrays

137 Pages·2016·2.64 MB·English

by  Chiara M. F. Mingarelli (auth.)

Springer Theses
Recognizing Outstanding Ph.D. Research
Chiara M. F. Mingarelli

Gravitational
Wave Astrophysics
with Pulsar
Timing Arrays
Springer Theses
Recognizing Outstanding Ph.D. Research
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Chiara M.F. Mingarelli
Gravitational Wave
Astrophysics with Pulsar
Timing Arrays
123
ChiaraM.F.Mingarelli,PhD
Physics,MathematicsandAstronomy
(TAPIRGroup)
CaliforniaInstituteofTechnology
Pasadena,CA,USA
ISSN2190-5053 ISSN2190-5061 (electronic)
SpringerTheses
ISBN978-3-319-18400-5 ISBN978-3-319-18401-2 (eBook)
DOI10.1007/978-3-319-18401-2
LibraryofCongressControlNumber:2015952623
SpringerChamHeidelbergNewYorkDordrechtLondon
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Formyfamilywhohasalwaysbelieved
inme,andforthechildrenwhodreamof
blackholes,spaceships,andotherworlds

Supervisor’s Foreword
The prediction of the existence of gravitational waves as one of the fundamental
consequencesofEinstein’stheoryofgeneralrelativityisalmostexactlyahundred
years old. Einstein thought gravitational waves would be unobservable due to the
intrinsicweaknessofthisformofradiation.However,aftermanydecadesdevoted
to the development of new instruments, a handful of detectors and observational
techniquesareapproachingasensitivityadequatetofinallycapturethesewaves.We
arepossiblyonthebrinkofarevolutionwiththefirstdirectdetectionfinallyinsight
andtheopeningupofanewobservationalwindowontheUniverse.
Oneofthetechniquesusedtosearchforgravitationalwavesisthemonitoringof
ultra-stable radio pulsars that provide a galactic-scale gravitational-wave detector,
apulsartimingarray.Thesearraysareparticularlysuitabletocapturegravitational
radiationfromsomeofthemostextremeobjectsinnature:binarysystemsofbillion-
solarmassblackholes.
ChiaraMingarelli’sPh.D.thesisopensnewresearchavenuesintheuseofpulsar
timing arrays (PTAs) to study populations of super-massive black hole binaries
throughgravitational-waveobservations.Herworkhasshownforthefirsttimethat
PTAscanyieldinformationaboutthenon-lineardynamicsofthegravitationalfield.
This is possible because PTAs collect, at the same time, radiation from the same
source emitted at stages of its binary evolution that are separated by thousands of
years.
Chiarahasalsobeenamongstthepioneersofthetechniquesthatwillallowusto
probethelevelofanisotropyofthediffusegravitational-wavebackgroundradiation
from the whole population of super-massive black hole binaries in the Universe.
Indeed, future observations will provide us with hints about the distribution of
galaxiesharboringmassiveblackholesandinsightsintoendproductsofhierarchical
mergersofgalaxies.
ProfessorAlbertoVecchio
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Acknowledgments
IwouldliketoexpressmysincerestgratitudetoAlbertoVecchio,mysupervisorand
mentor.Hishelp,encouragementandadvicehavebeeninvaluableoverthecourseof
myPh.D.Albertoplayedasmystrengthsandhelpedmetodevelopmyweaknesses
and,importantly,gavemeprojectswhichIcouldreallysinkmyteethinto.Iwould
also like to thank Will Farr for his frequent clear and insightful comments on my
work and my thesis examiners Ian Stevens and Ik Siong Heng for their astute and
penetrating comments and questions during my viva voce exam. Their comments
havewithoutadoubtmadethisthesisbetter.
I am very much obliged to all my colleagues and friends at the University of
Birmingham for making my time there very special, most of all to the following:
Alberto Vecchio, Andreas Freise, Will Farr, Mike Cruise, Katherine Grover, Ben
Aylott, Trevor Sidery, Ilya Mandel, Carl-Johan Haster, John Veitch, Christopher
Berry,BenFarr,DanBrown,HaixingMiao,MengyaoWang,CharlotteBond,Will
Vousden,MelissaGillone,RichardPearsonandMaggieLieu.Maggie,Ihopeyou
neverchange,exceptforwhenyoubecometheQueenofMars.
I also owe a great deal to Michaela Nelson, Chris Collins, Eleanor Chalkey,
Stuart Aston and Ludovico Carbone for their encouragement and their help with
my experimental work in the first year of my Ph.D. I don’t recall there ever being
amorebeautiful(orlarger!)MachZenderinterferometer:).Moreover,mygenuine
and sincerest thanks are owed to Andreas Freise, Yvonne Elsworth and Eleanor
Chalkley,whohelpedmetobelieveinmyselfinmomentsofdoubt.
Furthermore, I would like to thank all my colleagues in the EPTA for their
interestinmywork,theirsupportandconstantencouragement—especiallyMichael
Kramer,BenStappers,GemmaJanssen,AntoineLassus,StephenTaylor,Delphine
PerrodinandMartaBurgay.
A special thanks to Ingrid Stairs, Joseph Lazio, Sarah Burke–Spolaor, Michele
Vallisneri, Maura McLaughlin, Joseph Romano, Andrea Lommen and Xavier
Siemens, who have shown enthusiasm and interest in my work. I am very much
lookingforwardtoworkingwithNANOGravinthefuture.
For having passed on my acute caffeine addiction, I must offer my sincerest
apologiestoKatherineGrover,TrevorSideryandCarl-JohanHaster.Ourfrequent
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