I am a PhD student in the Astronomy and Astrophysics group at the University of Warwick. My supervisors are Tom Marsh and Danny Steeghs. My PhD focuses on AM CVns, a class of He-dominated cataclysmic variables which include the shortest period binaries known. I am particularly interested in the first fully-eclipsing AM CVn, Gaia14aae.
AM CVn-type binaries are laboratories of extreme physics and the dominant source of gravitational waves at frequencies detectable by a space interferometer such as LISA, as well as potential sources of dwarf novae, classical novae, type 1a supernovae, and ".1a" supernovae. They consist of a central white dwarf accreting He-rich material from a donor, which may be either another white dwarf or a He-atmosphere star.
Because of their low space density only around 50 are known. In 2014 the first fully-eclipsing AM CVn was discovered, Gaia14aae, offering an unprecedented wealth of information on the structure and evolutionary history of these objects. I am studying this system using high-speed photometry and time-resolved spectroscopy. Outreach
I am a regular writer for Astrobites, who summarise astro-ph papers aimed at an undergraduate level. I also volunteer for the department's planetarium, which is used on visits to local schools.
- "Phase-Resolved Spectroscopy of Gaia14aae: Line Emission From Near the White Dwarf Surface" -- MNRAS (2019), 485, 1947 -- M. J. Green, T. R. Marsh, D. Steeghs, E. Breedt, T. Kupfer, P. Rodriguez-Gil, J. van Roestel, R. P. Ashley, L. Wang, E. Cukanovaite, S. Outmani
- "A 15.7-Minute AM CVn Binary Discovered in K2" -- MNRAS (2018), 477, 5646 -- M. J. Green, J. J. Hermes, T. R. Marsh, D. T. H. Steeghs, Keaton J. Bell, S. P. Littlefair, S. G. Parsons, E. Dennihy, J. T. Fuchs, J. S. Reding, B. C. Kaiser, R. P. Ashley, E. Breedt, V. S. Dhillon, N. P. Gentile Fusillo, P. Kerry, D. I. Sahman
- "High-Speed Photometry of Gaia14aae: An Eclipsing AM CVn That Challenges Formation Models" -- MNRAS (2018), 476, 1663, -- M. J. Green, T. R. Marsh, D. T. H. Steeghs, T. Kupfer, R. P. Ashley, S. Bloemen, E. Breedt, H. C. Campbell, A. Chakpor, C. M. Copperwheat, V. S. Dhillon, G. Hallinan, L. K. Hardy, J. J. Hermes, P. Kerry, S. P. Littlefair, J. Milburn, S. G. Parsons, N. Prasert, J. van Roestel, D. I. Sahman, N. Singh
- "The physical properties of AM CVn stars: new insights from Gaia DR2" -- A&A 620, A141 (2018) -- G. Ramsay, M. J. Green, T. R. Marsh, T. Kupfer, E. Breedt, V. Korol, P.J. Groot, C. Knigge, G. Nelemans, D. Steeghs, P. Woudt, A. Aungwerojwit
- "A Refined Search for Pulsations in White Dwarf Companions to Millisecond Pulsars" -- MNRAS (2018) -- Mukremin Kilic, J. J. Hermes, A. H. Corsico, Alekzander Kosakowski, Warren R. Brown, John Antoniadis, Leila M. Calcaferro, A. Gianninas, Leandro G. Althaus, M. J. Green
- "The OmegaWhite survey for short-period variable stars - V. Discovery of an ultracompact hot subdwarf binary with a compact companion in a 44 minute orbit" -- ApJ (2017) -- T. Kupfer, G. Ramsay, J. van Roestel, J. Brooks, S. A. Macfarlane, R. Toma, P. J. Groot, P. A. Woudt, L. Bildsten, T. R. Marsh, M. J. Green, E. Breedt, D. Kilkenny, J. Freudenthal, S. Geier, U. Heber, S. Bagnulo, N. Blagorodnova, D. A. H. Buckley, V. S. Dhillon, S. R. Kulkarni, R. Lunnan, T. A. Prince
- "A search for optical bursts from the repeating fast radio burst FRB 121102" -- MNRAS (2017) -- Liam K Hardy, Vik S Dhillon, Laura G Spitler, Stuart P Littlefair, Richard P Ashley, Annalisa De Cia, Matthew J Green, Phrudth Jaroenjittichai, Evan F Keane, Paul Kerry, Michael Kramer, Daniele Malesani, Tom R Marsh, Steven G Parsons, Andrea Possenti, Somsawat Rattanasoon, David I Sahman
- "Testing the white dwarf mass-radius relationship with eclipsing binaries" -- MNRAS (2017) -- S. G. Parsons, B. T. Gänsicke, T. R. Marsh, R. P. Ashley, M. C. P. Bours, E. Breedt, M. R. Burleigh, C. M. Copperwheat, V. S. Dhillon, M. Green, L. K. Hardy, J. J. Hermes, P. Irawati, P. Kerry, S. P. Littlefair, M. J. McAllister, S. Rattanasoon, A. Rebassa-Mansergas, D. I. Sahman, M. R. Schreiber
- "Two white dwarfs in ultrashort binaries with detached, eclipsing, likely substellar companions detected by K2" -- MNRAS (2017) -- S. G. Parsons, J. J. Hermes, T. R. Marsh, B. T. Gänsicke, P.-E. Tremblay, S. P. Littlefair, D. I. Sahman, R. P. Ashley, M. Green, S. Rattanasoon, V. S. Dhillon, M. R. Burleigh, S. L. Casewell, D. A. H. Buckley, I. P. Braker, P. Irawati, E. Dennihy, P. Rodríguez-Gil, D. E. Winget, K. I. Winget, K. J. Bell, M. Kilic
- "Optical timing observations of Swift J1753.5-0127 during its Feb 2017 rejuvenation" -- ATel #10118 -- P. Gandhi (Southampton), V. S. Dhillon (Sheffield), T. R. Marsh, M. Green, R. P. Ashley (Warwick), D. Altamirano, A. Beri (Southampton), A. W. Shaw (Alberta), J. A. Tomsick (Berkeley)
- "Using large spectroscopic surveys to test the double degenerate model for Type Ia supernovae" -- MNRAS (2017), 468, 2910 -- Breedt, E.; Steeghs, D.; Marsh, T. R.; Gentile Fusillo, N. P.; Tremblay, P.-E.; Green, M.; De Pasquale, S.; Hermes, J. J.; Gänsicke, B. T.; Parsons, S. G.; Bours, M. C. P.; Longa-Peña, P.; Rebassa-Mansergas, A.
- "PTF1 J082340.04+081936.5: A Hot Subdwarf B Star with a Low-mass White Dwarf Companion in an 87-minute Orbit" -- ApJ (2017), 835, 131 -- Kupfer, Thomas; van Roestel, Jan; Brooks, Jared; Geier, Stephan; Marsh, Tom R.; Groot, Paul J.; Bloemen, Steven; Prince, Thomas A.; Bellm, Eric; Heber, Ulrich; Bildsten, Lars; Miller, Adam A.; Dyer, Martin J.; Dhillon, Vik S.; Green, Matthew; Irawati, Puji; Laher, Russ; Littlefair, Stuart P.; Shupe, David L.; Steidel, Charles C.; Rattansoon, Somsawat; Pettini, Max.
Conference Talks and Posters
- Talk: "Gaia14aae: An Eclipsing AM CVn that Challenges Formation Models" (Golden Age of Cataclysmic Variables IV, Palermo, September 2017)
- Talk: "Gaia14aae: An Eclipsing AM CVn that Challenges Formation Models" (NAM, Hull, July 2017)
- Poster: "An Update on Gaia14aae, the First Eclipsing AM CVn" (European White Dwarf Workshop, Warwick, June 2016). Proceedings.