Astrophysics at St.Andrews
Lead Research Organisation:
University of St Andrews
Department Name: Physics and Astronomy
Abstract
Our Galaxy contains many fossils of its formation history. Smaller galaxies that collided with the Milky Way long ago formed streams of stars that still linger as fossils of the Galaxy's formation, orbiting in the gravitational field of the Galaxy's primordial dark-matter halo. From 2011 the GAIA mission will map the positions and motions of these streams. We will develop new techniques to use data from GAIA to map the dark matter, and to test whether conventional theories of gravity work as expected at large distances. Clusters of new stars and planetary systems are constantly forming inside the dark clouds of gas and dust that delineate the Milky Way's spiral arms. In the biggest clusters, stars form that are up to 100 times as massive as the Sun. These massive stars burn so brightly that they are clearly visible in neighbouring galaxies. Many of them are binary stars. Our measurements of their mutual eclipses and spectra will reveal their sizes and temperatures, and hence the distances to the nearest galaxies. We do not yet understand how these massive stars form, or why so many of them are binaries. We will simulate how the most massive and hottest stars manage to form despite the tendency of their radiation fields to blow away the gas that feeds them. We also aim to find out how their winds, and the shock waves from the supernova explosions that eventually blow them apart, affect neighbouring gas clouds, perhaps triggering new bursts of star formation. The dark clouds where stars form contain needle-like dust grains that line up with the Galaxy's magnetic fields and polarize radiation passing through them. We will measure the polarization of infrared and mm-wave radiation coming from regions where cloud material is just beginning to form new stars, to discover what is happening to the magnetic field and to the grains themselves as the star condenses. Newly-born stars are surrounded by flat, rotating discs of gas and dust, which persist for two or three million years. As planets form in the disc material, some gas continues to feed the growing star, which at this stage possesses a strong magnetic field. We can now map these stars' magnetic fields using new instruments. We will use these maps to predict how the magnetic field acts to channel material into streams, and how the field structure regulates the flow rate on to the star and the star's spin. We will seek out rapidly rotating young stars near the Sun, in remnants of star clusters that formed up to 50 million years ago but fell apart. By this age the discs have gone, but an enigmatic fossil remnant of earlier processes lingers in their spin rates. Among otherwise identical stars in the same cluster, some spin much faster than others. We want to know if this difference in spin rate is a clue as to how many stars possess planetary systems, or if the difference originates in some peculiarity of the stars' magnetic fields. We will map the magnetic fields of the fast rotators and their more slowly-rotating siblings, to see if there is a difference in the rate at which hot gas flowing out along the field lines can carry away the star's spin. Finally, we will seek out planetary systems around nearby and distant stars. We are working with astronomers at several other institutions to monitor the brightnesses of hundreds of thousands of nearby stars, in order to pick out tiny dips in light caused by close-orbiting Jupiter-sized planets passing in front of their parent stars. We aim to discover dozens of such planets, and to measure their sizes, masses and temperatures. We will also search for planets further from their stars, by monitoring distant stars whose light is being temporarily magnified by the gravitational field of a foreground star. Distortions in the resulting light variation have already revealed Jupiter-mass planets around a couple of these foreground stars. We aim to find many more using a network of new robotic telescopes.
Organisations
Publications
McIvor T
(2006)
Simulated X-ray cycles in rapidly rotating solar-like stars
in Monthly Notices of the Royal Astronomical Society
Budding E
(2006)
Multisite, Multiwavelength Studies of the Active Cool Binary CC Eri
in Astrophysics and Space Science
Fynbo JP
(2006)
No supernovae associated with two long-duration gamma-ray bursts.
in Nature
Poulton C
(2006)
Detecting a rotation in the Eridani debris disc
in Monthly Notices of the Royal Astronomical Society
Keto E
(2006)
Observations on the Formation of Massive Stars by Accretion
in The Astrophysical Journal
Beaulieu JP
(2006)
Discovery of a cool planet of 5.5 Earth masses through gravitational microlensing.
in Nature
Zhao H
(2006)
Refining the MOND Interpolating Function and TeVeS Lagrangian
in The Astrophysical Journal
Lada C
(2006)
Spitzer Observations of IC 348: The Disk Population at 2-3 Million Years
in The Astronomical Journal
Hynes R
(2006)
Multiwavelength Observations of EXO 0748-676. I. Reprocessing of X-Ray Bursts
in The Astrophysical Journal
McIvor T
(2006)
Extrasolar planets, stellar winds and chromospheric hotspots
in Monthly Notices of the Royal Astronomical Society: Letters
Dobbs C
(2006)
Spurs and feathering in spiral galaxies
in Monthly Notices of the Royal Astronomical Society
Greaves J
(2006)
Space debris and planet detection
in Astronomy and Geophysics
Pollacco D
(2006)
The WASP Project and SuperWASP Camera
in Astrophysics and Space Science
Bentz M
(2006)
A Reverberation-based Mass for the Central Black Hole in NGC 4151
in The Astrophysical Journal
Christian D
(2006)
The WASP project in the era of robotic telescope networks
in Astronomische Nachrichten
Davies M
(2006)
Stellar encounters involving massive stars in young clusters Stellar encounters involving massive stars
in Monthly Notices of the Royal Astronomical Society
Dunstone N
(2006)
The coronal structure of Speedy Mic - II. Prominence masses and off-disc emission*
in Monthly Notices of the Royal Astronomical Society
Holzwarth V
(2006)
Theoretical mass loss rates of cool main-sequence stars
in Astronomy & Astrophysics
Rice W
(2006)
Dust filtration at gap edges: implications for the spectral energy distributions of discs with embedded planets
in Monthly Notices of the Royal Astronomical Society
Varnière P
(2006)
Observational Properties of Protoplanetary Disk Gaps
in The Astrophysical Journal
Horne K
(2006)
X-ray gas in the galaxy cluster Abell 2029: conformal gravity versus dark matter Conformal gravity analysis of Abell 2029
in Monthly Notices of the Royal Astronomical Society
Gould A
(2006)
Microlens OGLE-2005-BLG-169 Implies That Cool Neptune-like Planets Are Common
in The Astrophysical Journal
Bonnell I
(2006)
The Jeans mass and the origin of the knee in the IMF
in Monthly Notices of the Royal Astronomical Society
Stark D
(2006)
Near-Infrared Synthetic Images of Protostellar Disks and Envelopes
in The Astrophysical Journal
Hilditch R
(2006)
Eclipsing Binaries in Local Group Galaxies
in Astrophysics and Space Science
Jardine M
(2006)
X-ray emission from T Tauri stars
in Monthly Notices of the Royal Astronomical Society
Gregory S
(2006)
Rotationally modulated X-ray emission from T Tauri stars
in Monthly Notices of the Royal Astronomical Society
Jeffers S
(2006)
Hubble Space Telescope observations of SV Cam -- I. The importance of unresolved star-spot distributions in light-curve fitting
in Monthly Notices of the Royal Astronomical Society
Scholz A
(2006)
Exploring Brown Dwarf Disks: A 1.3 mm Survey in Taurus
in The Astrophysical Journal
Beichman C
(2006)
New Debris Disks around Nearby Main-Sequence Stars: Impact on the Direct Detection of Planets
in The Astrophysical Journal
Wilson D
(2006)
SuperWASP Observations of the Transiting Extrasolar Planet XO-1b
in Publications of the Astronomical Society of the Pacific
Greaves J
(2006)
Metallicity, debris discs and planets
in Monthly Notices of the Royal Astronomical Society
Denney K
(2006)
The Mass of the Black Hole in the Seyfert 1 Galaxy NGC 4593 from Reverberation Mapping
in The Astrophysical Journal
Cassan A
(2006)
OGLE 2004-BLG-254: a K3 III Galactic bulge giant spatially resolved by a single microlens
in Astronomy & Astrophysics
Chen D
(2006)
Strong Lensing Probability for Testing TeVeS Theory
in The Astrophysical Journal
Bramich D
(2006)
Upper limits on the hot Jupiter fraction in the field of NGC 7789
in Monthly Notices of the Royal Astronomical Society
Holzwarth V
(2006)
The impact of meridional circulation on stellar butterfly diagrams and polar caps Stellar butterfly diagrams and polar caps
in Monthly Notices of the Royal Astronomical Society
Smith A
(2006)
The impact of correlated noise on SuperWASP detection rates for transiting extrasolar planets
in Monthly Notices of the Royal Astronomical Society
Clark P
(2006)
Clumpy shocks and the clump mass function
in Monthly Notices of the Royal Astronomical Society
Bonnell I
(2006)
Spiral shocks, triggering of star formation and the velocity dispersion in giant molecular clouds
in Monthly Notices of the Royal Astronomical Society
Zhao H
(2006)
Concordance of Kinematics and Lensing of Elliptical Galaxies with WMAP Cosmology
in Chinese Journal of Astronomy and Astrophysics
Jeffers S
(2006)
Hubble Space Telescope observations of SV Cam - II. First derivative light-curve modelling using phoenix and atlas model atmospheres
in Monthly Notices of the Royal Astronomical Society
Christian D
(2006)
The SuperWASP wide-field exoplanetary transit survey: candidates from fields 23 h < RA < 03 h
in Monthly Notices of the Royal Astronomical Society
Rice W
(2006)
Planetesimal formation via fragmentation in sel-gravitating protoplanetary discs
in Monthly Notices of the Royal Astronomical Society: Letters
Gregory S
(2006)
Mass accretion on to T Tauri stars
in Monthly Notices of the Royal Astronomical Society
Dobbs C
(2006)
The formation of molecular clouds in spiral galaxies
in Monthly Notices of the Royal Astronomical Society
Dominik M
(2006)
Stochastic distributions of lens and source properties for observed galactic microlensing events
in Monthly Notices of the Royal Astronomical Society
Donati J
(2006)
The surprising magnetic topology of Sco: fossil remnant or dynamo output?
in Monthly Notices of the Royal Astronomical Society
Zhao H
(2006)
Roche lobe shapes for testing MOND-like modified gravities
in Astronomy & Astrophysics
Collier Cameron A
(2006)
A fast hybrid algorithm for exoplanetary transit searches
in Monthly Notices of the Royal Astronomical Society
Description | Not applicable this year |
Exploitation Route | Not applicable this year |
Sectors | Education |