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Institute of Astronomy University of Cambridge Natural Sciences Tripos Part III/MASt Astrophysics Project Booklet Version date: 7th October 2016 2016-2017 Editors: Ian Parry, George Efstathiou and Judith Moss CONTENTS # Supervisor(s) Assoc.UTO/ Project title pp 2nd supervisor 1 Robert Izzard Christopher Tout Asterosemismology of stellar populations 2 2 Robert Izzard Christopher Tout The Galactic stellar population of single and 3 binary stars 3 Paula Jofre, [Gerry Gilmore] Cosmic trees: understanding the relationships 4-5 Gerry Gilmore between different generations of stars 4 John Ilee, Farzana Meru, [Cathie Clarke] The chemical effects of tidal interaction in the 6-7 Cathie Clarke RW Aurigae system 5 Amy Bonsor, Quentin [Mark Wyatt] Gas around white dwarfs 8-9 Kral and Mark Wyatt 6 Grant Kennedy, [Mark Wyatt] A better search for Tatooine 10-11 Mark Wyatt 7 Grant Kennedy, [Mark Wyatt] The long arm of binary perturbations to 12-13 Mark Wyatt planetary systems 8 Thomas de Boer The stellar populations of the Sagittarius dwarf 14-15 spheroidal galaxy 9 Girish Kulkarni, [Martin Haehnelt] Intensity Mapping of the High-Redshift Universe 16-17 Martin Haehnelt 10 Clare Worley, [Gerry Gilmore] Simulating the Gaia-ESO Selection Function 18 Anna Hourihane, Gerry Gilmore 11 Clare Worley, [Gerry Gilmore] Data-mining stellar evolution samples in the 19 Gerry Gilmore AMBRE catalogue 12 Nick Bate, Paul Hewett [Paul Hewett] Hot spots and warps in quasar accretion discs 20-21 13 Ciro Pinto,Anne Lohfink, [Andy Fabian] Extreme matter accretion onto black holes in 22-23 Andy Fabian ultraluminous X-ray sources 14 Ciro Pinto, Andy Fabian [Andy Fabian] The fight between cooling and heating in 24-25 clusters of galaxies 15 Roman Rafikov Cathie Clarke Understanding the Outcomes of Planet-Planet 26-27 Scattering I Supervisor(s) Assoc.UTO/ Project title # 2nd supervisor # 16 Roman Rafikov Cathie Clarke Signs of Planetary Demise Around White Dwarfs 28-29 17 Ian Parry Can we observe the A-band oxygen biomarker 30 in Proxima b with the European Extremely Large Telescope? 18 Ian Parry Searching for signs of life using a large spinning 31 space telescope 19 Amaury Triaud, Nikku How long is a day when a planet has two Suns? 32-33 John Papaloizou Madhusudhan 20 Christopher Tout, [Christopher Tout] Lithium Production by Hot-bottom Burning 34-35 Robert Izzard 21 Giulio del Zanna Henrik Latter Signatures of nanoflare heating in solar active 36-37 regions 22 Rik van Lieshout, Mark [Mark Wyatt] Strange Kepler light curves: Modelling the dips 38-39 Wyatt, Grant Kennedy of KIC 8462852 as transiting dust clouds 23 Rik van Lieshout, Amy [Mark Wyatt] Circularising spaghettified asteroids around 40-41 Bonsor, Mark Wyatt white dwarfs 24 Giovanni Rosotti, [Cathie Clarke] The impact of the birth environment on the 42-43 Cathie Clarke lifetime of proto-planetary discs 25 Ghina Halabi Christopher Tout Nucleosynthesis in Single and Binary Stars of 44 Intermediate Mass 26 Denis Erkal, [Vasily Belokurov] 45-46 Vasily Belokurov The effect of the Milky Way bar on tidal streams 27 Farzana Meru Cathie Clarke Can planets survive in young turbulent 47 protoplanetary discs? 28 William Alston, Andy [Andy Fabian] The high-frequency rms-flux relation in 48-49 Fabian accreting black holes 29 Richard Booth, Cathie [Cathie Clarke] Accretion and the location of planet formation 50-51 Clarke, Amaury Triaud in binary systems II # Supervisor(s) Assoc.UTO/ Project title pp 2nd supervisor 30 James Fergusson Anthony Challinor Parameter constraints from the CMB 52 31 Taysun Kimm [Martin Haehnelt] 53-54 Martin Haehnelt Lyman Alpha Profile of Simulated Galaxies 32 Cathie Clarke, [Mike Irwin] The search for a hot Jupiter in the young star FU 55-56 Mike Irwin Orionis 33 Paul Hewett A search for redshifted emission in the quasar 57-59 population – constraining the properties of outflows and inflows 34 Mark Wyatt Modelling the stochastic replenishment of 60 exozodiacal debris disks 35 Paula Jofre Christopher Tout Blue stragglers: can lithium tell us if a star has 61-62 experienced cannibalism? 36 Nic Walton Gerry Gilmore Planetary Nebulae Revealed by Gaia: Distances 63-64 and Dynamics 37 Richard McMahon, [Richard ALMA observations of star formation in the host 65-66 Manda Banerji, McMahon] galaxies of quasars and the coevolution of Peter Hague supermassive black holes 38 Thomas Maedler Gerry Gilmore Wobbling holostars 67-68 39 Vasily Belokurov [Wyn Evans] Uncovering the Milky Way with variable stars in 69-70 Wyn Evans Gaia DR1 #1 40 Vasily Belokurov [Wyn Evans] Uncovering the Milky Way with variable stars in 71-72 Wyn Evans Gaia DR1 #2 41 Jean Teyssandier Mark Wyatt Formation of hot Jupiters via high-eccentricity 73-74 mechanisms APPENDIX – Project timetable format and 75-77 content Contact Lists: Supervisors (project # order) 78-80 81 Supervisors (alphabetical) III Part III/MASt Astrophysics 2016-2017 Version: 7th October 2016 Introduction This booklet contains descriptions of the individual projects available in the academic year 2016- 2017. Each entry contains a brief description of the background to the project along with a summary of the type of work involved and several references where more information can be obtained. The booklet is made available just before the start of the Michaelmas term to give students about 2 weeks to choose which projects they are interested in. George Efstathiou Part III/MASt Astrophysics Course Coordinator 2016-2017 Page 1 Part III/MASt Astrophysics 2016-2017 Version: 7th October 2016 1. Part III project: Asterosemismology of stellar populations Context Asteroseismology is a vastly underused and underestimated statistical tool. The pulsa- tional properties of a star tell us much about its evolutionary state, e.g. Cepheids, Miras, RR Lyraes (see e.g. https://www.aavso.org/types-variables). Aim The recent paper of Jeffery, C. S. & Saio, H. 2016, MNRAS, 458, 1352 predicts which stars pulsate as a function of temperature,luminosity,mass and chemical abundance in all phases of stellarevolutionfrom main-sequencestars to giants. The task of this project is to combine this data with our single- and binary-star population code binary_c. A prediction of the the timescales that stars spend in each of these pulsating phases will be made, and hence the number of pulsating stars in each region of the Hertzsprung-Russell diagram will be made. This data will be directly comparable to the number of observed pulsating stars, such as Cepheids, and provide a useful guide to observing strategies and constraints on their evol- utionary channels. The final aim is to combine the generated population with the Kepler selection function to determine the numbers and properties of pulsating stars of different types observed by Kepler, in all phases of stellar evolution, and in both single and binary stars. This will be compared to Sharma et al. (2016), and the contribution of binary stars to the Kepler sample quantified (cf. Jofre et al. 2016). Education Astrophysics/astronomy: stellar evolution and hydrodynamics. Technical: coding (Linux, C, Perl). Presentation and communication skills. Collaborators Stellar group, Simon Jeffery (Armagh Observatory). Reading • Neilson, H. R., Schneider, F.R. N., Izzard, R. G., Evans, N. R., & Langer, N. 2015, A&A, 574, A2 • Miglio, A., Eggenberger, P., Girardi, L., & Montalbán, J., eds. 2015, Astrophysics and Space Science Proceedings, Vol. 39, Asteroseismology of Stellar Populations in the Milky Way • Jeffery, C. S. & Saio, H. 2016,MNRAS, 458, 1352 • Izzard, R. G., Tout, C. A., Karakas, A. I., & Pols, O. R. 2004, MNRAS, 350, 407 • Izzard, R. G., Dray, L. M., Karakas, A. I., Lugaro, M., & Tout, C. A. 2006, A&A, 460,565 • Izzard, R. G., Glebbeek, E., Stancliffe, R. J., & Pols, O. R. 2009, A&A, 508, 1359 • http://www.ast.cam.ac.uk/∼rgi/binary_c.html Hertzsprung-Russell, or luminosity-temperature, diagram showing locations of pulsating variable stars coloured by spectral type. Taken from Jeffery & Saio (2016, Fig. 1). Small red numbers are stellar masses. Shadings are different types of pulsations (p-modes , g modes , strange modes 9, acoustic modes ≡). Project No. 1 Page 2 Part III/MASt Astrophysics 2016-2017 Version: 7th October 2016 2. Part III project: The Galactic stellar population of single and binary stars Context With the forthcoming Gaia data release, it is more important than ever that we model the stars in our Galaxy as accurately as possible. Models of our galaxy have been developed previously (e.g. the Be- sançon model) but not applied to our single/binary stellar population models. We require an accurate model of the distribution of stars in the Galaxy, as well as their birth parameters (chemistry, binary frac- tion, initial mass distribution etc.), to determine the properties of stellar populations in a very general way. Selection effects in the broadest sense will have to be taken into account. Aim Develop a model of the Galactic distribution of stars as a function of position, age (i.e. star formation history) and metallicity, suitable for implementing into the binary_c population synthesis code. This will require a literature survey of the current attempts to model galactic stellar populations, e.g. the Besançon model and that implemented in Gaia simulations, and a decision on which is the “best” for our purposes. An efficient model will be implemented that can take our binary population data as in- put and generate a model of the Galaxy, such that all the stellar populations currently modelled can be counted as a function of position on the sky. Selection effects, such as an extinction law, will have to be implemented to count magnitude- and volume-limited surveys. The Gaia colours have already been implemented,but not well tested, so this could also form part of the project. The first Gaia release should be available by the time the project starts, but are already preliminary datasets (e.g Hipparcos) which could be used as test data.
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