White Dwarf Binary Stars
Lead Research Organisation:
University of Warwick
Department Name: Physics
Abstract
White dwarfs are the most common end-point of stellar evolution and there are many millions of them,
both isolated and within binary systems, in our Galaxy. The focus of this project will be the evolution of
white dwarfs in binary systems as can be traced through precision measurements of masses. Particular
emphasis will be given to double white dwarf systems, both detached and mass-transferring, to understand
the origin and evolution of the accreting systems. This work will be carried out just as the Gaia survey starts
to transform the field, and exploration of Gaia's potential will play a major part in the project. The project
will involve both survey mining in an effort to find new systems and study binary populations as well as detailed
characterisation of individual systems.
both isolated and within binary systems, in our Galaxy. The focus of this project will be the evolution of
white dwarfs in binary systems as can be traced through precision measurements of masses. Particular
emphasis will be given to double white dwarf systems, both detached and mass-transferring, to understand
the origin and evolution of the accreting systems. This work will be carried out just as the Gaia survey starts
to transform the field, and exploration of Gaia's potential will play a major part in the project. The project
will involve both survey mining in an effort to find new systems and study binary populations as well as detailed
characterisation of individual systems.
Publications
Green M
(2019)
Phase-resolved spectroscopy of Gaia14aae: line emission from near the white dwarf surface
in Monthly Notices of the Royal Astronomical Society
Green M
(2018)
A 15.7-Minute AM CVn Binary Discovered in K2
in Monthly Notices of the Royal Astronomical Society
Green M
(2018)
High-speed photometry of Gaia14aae: an eclipsing AM CVn that challenges formation models
in Monthly Notices of the Royal Astronomical Society
Studentship Projects
Project Reference | Relationship | Related To | Start | End | Student Name |
---|---|---|---|---|---|
ST/N504506/1 | 01/10/2015 | 31/03/2021 | |||
1622597 | Studentship | ST/N504506/1 | 05/10/2015 | 31/03/2019 | Matthew Green |
Description | AM CVns in Gaia |
Organisation | Armagh Observatory and Planetarium |
Department | Armagh Observatory |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Provided a portion of the data analysis and text for the paper which was published in 2018. |
Collaborator Contribution | Analysis was provided by multiple researchers worldwide, collated by PI (Gavin Ramsay) |
Impact | A paper was published in 2018 (Ramsay et al, 2018A&A...620A.141R) |
Start Year | 2017 |
Description | Thomas Kupfer |
Organisation | California Institute of Technology |
Department | Caltech Astronomy |
Country | United States |
Sector | Academic/University |
PI Contribution | I led a project for which Caltech contributed data. Additionally I have performed the collection and reduction (first stage analysis) of data for several projects led by Caltech. |
Collaborator Contribution | Using the CHIMERA instrument, Caltech collected data which was published in a journal article led by me. Additionally Caltech led several projects (including writing the papers) for which I contributed data or data analysis. |
Impact | "High-Speed Photometry of Gaia14aae: An Eclipsing AM CVn That Challenges Formation Models" -- MNRAS (2018). "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). "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. |
Start Year | 2016 |
Description | Ultracam |
Organisation | University of Sheffield |
Department | Department of Physics and Astronomy |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | I have collected data using the Ultracam instrument to contribute towards various collaboration projects. I have led one such project. |
Collaborator Contribution | All team members take part in data collection. Various team members have led projects which I have contributed to. |
Impact | "High-Speed Photometry of Gaia14aae: An Eclipsing AM CVn That Challenges Formation Models" -- MNRAS (2018). "A search for optical bursts from the repeating fast radio burst FRB 121102" -- MNRAS (2017). "Testing the white dwarf mass-radius relationship with eclipsing binaries" -- MNRAS (2017). "Two white dwarfs in ultrashort binaries with detached, eclipsing, likely substellar companions detected by K2" -- MNRAS (2017). |
Start Year | 2015 |
Description | Evening seminars |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Postgraduate students |
Results and Impact | Casual talks are held fortnightly in which postgrad students present their work to each other. I have presented annually for the past two years. |
Year(s) Of Engagement Activity | 2017,2018 |
Description | Planetarium School Visits |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | Regional |
Primary Audience | Schools |
Results and Impact | Regular visits to local schools using the department planetarium. Videos are shown to the audience, often with narration by the presenter. This is generally followed by a question and answer session about astronomy. The audience is most often primary-age school children, but occasionally secondary school or general public level as well. Each show takes an audience of approximately 15, there are generally 4-10 shows per visit, and I have taken part in visits approximately once every 2-4 months. |
Year(s) Of Engagement Activity | 2015,2016,2017,2018 |