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Structure, Properties and Formation Histories of S0 Galaxies Structure, Properties and Formation Histories of S0 Galaxies by Kaustubh Vaghmare Thesis Supervisor Prof. Ajit K. Kembhavi A thesis presented for the degree of Doctor of Philosophy to IUCAA & Jawaharlal Nehru University India July, 2015 Structure, Properties and Formation Histories of S0 Galaxies by Kaustubh Vaghmare c 2015 All rights reserved. Certificate This is to certify that the thesis entitled Structure, Properties and Formation Histories of S0 Galaxies submitted by Mr. Kaustubh Vaghmare for the award of the degree of Doctor of Philosophy to Jawaharlal Nehru University, New Delhi is his original work. This has not been published or submitted to any other University for any other Degree or Diploma. Pune July 30th, 2015 Prof. Ajit K. Kembhavi (Thesis Advisor & Director, IUCAA) Declaration I hereby declare that the work reported in this thesis is entirely original. This thesis is composed independently by me at the Inter-University Centre for Astronomy and Astrophysics, Pune under the supervision of Prof. Ajit K. Kembhavi. I further declare that the subject matter presented in the thesis has not previously formed the basis for the award of any degree, diploma, associateship, fellowship or any other similar title of any University or Institution. Pune July 30th, 2015 Prof. Ajit K. Kembhavi Mr. Kaustubh Vaghmare (Thesis Advisor) (Ph.D. Candidate) 3 Dedicated to ... Prathama & Prakash (my parents, my Gods) Rahul (my brother, whose ever presence with my parents and unquestioning support allowed me to work in peace) & Sneha (my beloved) 5 Acknowledgements For all students and regular visitors, it is clear that Prof. Ajit Kembhavi is one of the busiest people with frequent meetings, visits abroad, directorial duties and several other responsibilities. A testament to this is the simple fact that parts of this thesis have actually been corrected by him while waiting in South Block, New Delhi. A question I have been asked often is - how has it been to work with him? How did you manage? Do you wish you had worked with someone else? And my answer has been the same always. Yes, it has been difficult no doubt but when I compare myself with what I was when I got started and what I am today, I see so much growth. The growth has not just been academic. I have grown as a teacher, a mentor, a manager, a team member etc. In every single interaction with him, there was a lot I could learn in a short time. And even when I was not interacting with him, I found myself busy wrapping my head around his method of work and management. And I find myself privileged to have had the chance to work with him. Thanks to him, I had a chance to be a part of many committees and projects. I have had the chance to do work beyond my main thesis topic and grow in several directions. The general difficulty of working with a supervisor as busy as Prof. Kembhavi was manageable greatly because of Sudhanshu Barway's guidance. Sudhanshu has been a great mentor, the co-brainstormer behind all the projects in this thesis. His general advice on surviving graduate school days has also proved valuable. He has generously hosted me at the South African Astronomical Observatory in Cape Town on multiple occassions. During my trips to Cape Town, his wife Anjali and daughter Nihira opened their doors for me and gave me a home away from home for which I remain ever grateful. In the initial days of my PhD, I drew a lot of wisdom and help from Yogesh Wadadekar. His course on Astronomical Techniques was probably what cemented my decision that I wanted to work on Observational Astronomy. Through his course I was introduced to the Python programming language, a skill which has remained the corner stone of all my analysis done for the work in this thesis and beyond. During the later days of my graduate school, Varun Bhalerao joined as a postdoctoral fellow and Ashish Mahabal became a frequent visitor to IUCAA. With Varun, I had 7 the chance of doing a project that allowed me a glimpse of transient astronomy and with Ashish, I found myself expanding my skill set to large databases by working on the Catalina Real-time Transient Survey Virtual Observatory project. I can safely say that my growth in management skills and use of computational machinery grew exponentially thanks to my interactions with them. In the early days of learning photometry and IRAF, Vijay Mohan, one of the most patient teachers I know of, groomed me into using all the tools. And later when I took it on myself to master the fine art of spectroscopic analysis, I received a lot of help from Hadi Rahmani, Vivek and Anand. Finally, I learned most of the SALT data analysis and spectral modelling from Petri Vaisanen (SAAO) and his student Rajin Ramphul (UCT). I also had the privilege of interacting with Steve Crawford, Alexei Kniazev, Christian Hettlage, Kevin Hainline and David Buckley during my visits to Cape Town and learned a lot through discussions with them. A good deal of my time in graduate school was spent working for the Virtual Observatory India project. I had the chance of working with a fine team comprising of software engineers from both IUCAA and Persistent Systems Pvt Ltd. My thanks to Santosh Jagade, Ajay Vibhute, Sharmad Navalkar, Prerak Garg, and Snehal Valame. To Santosh and Ajay, along with Sagar and Prafull, I also thank them for the significant amount of improvement in my skill at playing badminton, all their help in lab workshops conducted by me at IUCAA and the tea table fun with Neelam and Praveen. And what is graduate school without your batch mates, your partners in crime? My gratitude to Luke Chamandy for his constant support and advice, my thanks to Rosy, Tina and Tori - you guys are great! And for bearing witness to my dare devil acts on the IUCAA terrace, the constant mimicry, for bearing my loud music, my very bad guitar playing, my annoying use of whistles as replacement to door knocking etc. I owe one (oops, many) to Suprit, my good friend and balcony mate (a phrase that the younger generation of students have replaced with the more disgusting phrase bathroom mate). And hey, you do need one senior student to keep warning you of the pot holes ahead and advise you both when needed and otherwise - Sibashish played this role perfectly. One of the things that kept me sane during my time in IUCAA was my partici- pation in public outreach. There was something about speaking to school & college children, and the general audience which was refreshing to do. And for the opportu- nities provided to me to do this, I am very thankful to Arvind Paranjpye and Samir Dhurde. The inspiration to look at science outreach as an important undertaking came from the inspiring works of Prof. Jayant Narlikar and the late Carl Sagan. My thanks to all members of the science outreach team for having supported me in all these activities. My thanks also to Ranjeev, Durgesh and Kanak for advices on various aspects of academia. Having travelled abroad as well as around India, having seen events small and big, if there is one conclusion I can say I have reached without any doubt, is this - IUCAA has the best administrative team (period). Everything in IUCAA is taken care of and I cannot ask for more. I have been helped by all of them with no questions asked and I would like to thank all of them. With many, I have developed strong personal rapports and will carry them always in my heart. I especially miss Susan Kuriakose, whose untimely passing away was perhaps the most shocking thing to happen. My special thanks to Sandeep for always squeezing me into Prof. Kembhavi's schedule, Samak for all the superb PJs, Chella for his confident and reassuring nods, Santosh Khadilkar for his we'll manage it attitude, Samuel for the ever present gesture inviting me in his office, Deepika, for making travel itineraries look easy (they are not!), Mukund Sahasrabuddhe for making accounting look trivial (again, it's not), Rajesh Pardeshi for all the of course, it's our job statements and Goswamiji for all the fikar na karo, ho jayegas. My thanks to every single person in the administration and the support staff. How often do you get to talk to people who have braved the enemy when it tried to enter your country? For me, it was a singular privilege that I was protected on all four directions by people with such experience. And to add to it, these security personnels of IUCAA were always willing to share their experiences, their war time stories and what not! And what to say about the cosmetic staff, the folks manning the receptions, the engineers - ever alert - all making everything go like clockwork! One of the central aspects about IUCAA is the visitor programme which allows one to meet an amazing diversity of people across the globe. I have met many people during the course of last several years, all of whom had a lot to teach me - George Djorgovski, George Helou, Poshak Gandhi, Smita Mathur, Sajeeth Phillip, C D Ravikumar, Asis & Tanuka Chattopadhaya, Amit Pathak, Shantanu Rastogi, Gazi Ahmed, Changbom Park, and Devraj Pawar. I now step back in time and recollect the people who inspired me to do science in general. I especially recollect the time back in ninth grade (or standard), a time where a series of low scores in Mathematics and Science convinced me that I was not meant to do science.
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