Structure of the M31 satellite system : bayesian distances from the tip of the red giant branch Anthony Rhys Conn To cite this version: Anthony Rhys Conn. Structure of the M31 satellite system : bayesian distances from the tip of the red giant branch. Other. Université de Strasbourg; Macquarie university (Sydney, Australie), 2013. English. NNT : 2013STRAH002. tel-01012081 HAL Id: tel-01012081 https://tel.archives-ouvertes.fr/tel-01012081 Submitted on 25 Jun 2014 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. UNIVERSITÉ DE STRASBOURG A thesis presented to Observatoire astronomique de Strasbourg by: Anthony Rhys CONN defended on : 7 February 2013 for the degree of : Docteur de l’université de Strasbourg Discipline: Astrophysics Structure of the M31 Satellite System: Bayesian Distances from the Tip of the Red Giant Branch Thesis Supervisors : Dr. Rodrigo A. Ibata Université de Strasbourg Prof. Quentin A. Parker Macquarie University Prof. Geraint F. Lewis University of Sydney A/Prof. Daniel B. Zucker Macquarie University Members of the Jury : Prof. Christian M. Boily Université de Strasbourg Dr. Michele Bellazzini INAF—Osservatorio Astronomico di Bologna Dr. Annie C. Robin Observatoire de Besançon External Examiner : Dr. Andreas Koch University of Heidelberg Completed under a cotutelle agreement with Macquarie University in Sydney Australia ii !c Anthony Rhys Conn, 2013. Typeset in LATEX 2ε. iii Except where acknowledged in the customary manner, the material presented in this thesis is, to the best of my knowl- edge, original and has not been submitted in whole or part for a degree in any university. Anthony Rhys Conn iv Acknowledgements I have been very fortunate throughout my PhD candidature to work with some very dedicated and talented astronomers and astrophysicists who have had a huge impact on the course my research has taken. I have worked most closely with my supervisors Dr Rodrigo Ibata (Universite´ de Strasbourg) and Prof. Geraint Lewis (University of Sydney) who I would like to thank for the large amount of their time and resources they have invested in my project. Rodrigo is a renowned figure in the field of Galactic Archaeology and I have greatly benefited from his expertise. He has also been a great host on my many visits to Strasbourg and always available to discuss the problem at hand. Likewise Geraint has had a prolific impact on the field and is a veritable source of programming knowhow. He devotes an enormous amount of energy to the various projects of his many students and his input has been invaluable to my research. In addition, I would also like to thank my supervisors Prof. Quentin Parker and A/Prof. Dan Zucker (both from Macquarie University) for their constant support and encouragement. In particular I am indebted to Quentin for the great lengths he went to in securing a funded position for me at Macquarie and for his efforts in establishing and maintaining the cotutelle agreement with the Universite´ de Strasbourg. Whilst my PhD project was somewhat external to the fields of expertise of both Quentin and Dan, they have always made themselves available to discuss my work at length and advise on all matters of administration. In addition to the contributions of my 4 supervisors, there are a number of other people who have played an important role in my progress toward completion. I would especially v vi Acknowledgements like to thank all the members of the Pan Andromeda Archaeological Survey (PAndAS) col- laboration for providing a wonderful repository of data to work with and particularly those members included as coauthors on my papers for their detailed reviews of my drafts. I would also like to add that I had many meetings with Dr Nicolas Martin (Universite´ de Strasbourg) whilst in Strasbourg which had a large impact on the work presented in Paper II. In addition I must thank Neil Ibata for his French translation of my thesis summary (Resum´ e´ de These).` I also received much support from my fellow PhD student Dr Anjali Varghese on my many trips to Strasbourg and relied on her superior French more than once. There are also a number of institutions that I must acknowledge for the support they have provided. Firstly, I would like to thank Macquarie University for their financial support via the Macquarie University Research Excellence Scholarship (MQRES) and also for paying all my airfares and providing assistance with other expenses incurred during my candidature. I would also like to thank the Observatoire Astronomique of the Universite´ de Strasbourg for providing me with accommodation on each visit to Strasbourg and I would like to thank both the aforementioned universities as well as the University of Sydney for use of computational and all other facilities. Finally I would like to thank all of my family for their ceaseless support and encour- agement. Without my family it is inconceivable that I could ever have made it this far. I would therefore like to dedicate this work to all of them: Mum, Dad, Nanna, Pa, Mardi, Pop, Andrew, Crysta, Sophie, Kristin, Remo, Alex, Chris, Matthew, Trixie and all my extended family. A Note on Paper Co-Author Contributions As a thesis by publication, much of the work contained in the main body of this thesis has been (or will be) published in the form of three separate papers submitted to the Astrophys- ical Journal. Each of these publications acknowledges contributions from a relatively large group of co-authors. This is an inevitable consequence of the use of data that is the property of a large collaboration (i.e. the Pan-Andromeda Archaeological Survey - PAndAS), and it has in no way diminished the amount of work that I have put into each of these papers. In fact, rather the opposite is true, due to the enormous amount of code adjustments and paper editing that has had to take place to accommodate the suggestions of a large group of people. The work contained in these papers has been carried out principally with the direction of the second and third co-authors, my supervisors Prof. Geraint Lewis and Dr Rodrigo Ibata, with all other contributions being in the form of written critiques of the paper drafts. This does not detract from the aid I have received from my other two supervisors Prof. Quentin Parker and A/Prof. Dan Zucker, who as well as providing similar critiques of my drafts, have been a great help with all administrational matters that I have contended with during the course of my PhD candidature. I should also note that I had many in-person discussions with Dr Nico- las Martin whilst in Strasbourg, which further influenced the way I carried out the analysis contained in the second paper. All of this said, all three papers have been written entirely by me, and all figures they contain have been generated by me using the PGPLOT plotting package (Pearson, 2011), with the sole exception of the pole-density plots in Paper III; Ch. 5 (Figs. 2, 4, 8, 10 (right-hand column of plots), 11 and 14), which were produced using a Gaussian-smoothing vii viii ANote on Paper Co-Author Contributions program by Geraint Lewis from the pole count analysis data that I sent him. All of the analysis contained in the papers has been undertaken using Fortran code that I have written from scratch, with examples of most of the principal versions of the code provided in the appendix. These programs do make occasional use of subroutines written by others, as now stated: I The “PolyS elect” subroutine is built around code written by Rodrigo Ibata, which uses the functions “in poly” and “ f imag” written by him. Given a series of points defin- ing the corners of a polygon, it determines whether or not a given point is inside this polygon. I use this routine to make colour-cuts on the Colour-Magnitude Diagram (see calls of this subroutine in MF TRGB. f 95; Appendix C for example) and also to re- ject random satellites drawn outside of the PAndAS survey area in my “RandomPoints” subroutine, used in the analysis of Paper III. II Part of the SVDFitter subroutine called in MF TRGB. f 95 (and earlier versions of this program) has been modified by Geraint Lewis. III The “ f unc i” function called in MF TRGB. f 95 (and earlier versions of this program) gives the photometric error as a function of magnitude in CFHT i-band for the PAndAS data and was provided by Rodrigo Ibata. IV The “k verse alpha” subroutine called in S atDensity S ampCont. f 95 (Appendix C) makes use of data generated by Geraint Lewis (k vs alpha.dat), which accounts for the volume of space covered by the PAndAS survey area as a function of distance from M31. V Several subroutines from Numerical Recipes (Press et al., 1992) have been used to per- form standard functions by various programs I have written, in particular MF TRGB. f 95. In the programs listed in the appendices, use of these algorithms are generally noted at the end of the program with commented double lines and the words ‘Libpress Algo- rithms’ embedded. The Numerical Recipes subroutines themselves are not shown for the sake of brevity, but any subroutine or function that is called from the code as printed ix in the appendices and yet is apparently absent from this printed code can be assumed to be from Numerical Recipes.