Till sidans topp

Sidansvarig: Webbredaktion
Sidan uppdaterades: 2012-09-11 15:12

Tipsa en vän
Utskriftsversion

Eddington capture sphere … - Göteborgs universitet Till startsida
Webbkarta
Till innehåll Läs mer om hur kakor används på gu.se

Eddington capture sphere around luminous stars

Artikel i vetenskaplig tidskrift
Författare Adam Stahl
Maciej Wielgus
Marek A Abramowicz
Wlodek Kluźniak
Wenfei Yu
Publicerad i Astronomy and Astrophysics
Volym 546
Nummer/häfte 10
Sidor artikel nr A54
ISSN 0004-6361
Publiceringsår 2012
Publicerad vid Institutionen för fysik (GU)
Sidor artikel nr A54
Språk en
Länkar dx.doi.org/10.1051/0004-6361/201220...
www.aanda.org/index.php?option=com_...
Ämneskategorier Högenergiastrofysik, Astronomi

Sammanfattning

Test particles infalling from infinity onto a compact spherical star with a mildly super-Eddington luminosity at its surface are typically trapped on the “Eddington capture sphere” and do not reach the surface of the star. The presence of a sphere on which radiation pressure balances gravity for static particles was first discovered some twenty five years ago. Subsequently, it was shown to be a capture sphere for particles in radial motion, and more recently also for particles in non-radial motion, in which the Poynting-Robertson radiation drag efficiently removes the orbital angular momentum of the particles, reducing it to zero. Here we develop this idea further, showing that “levitation” on the Eddington sphere (above the stellar surface) is a state of stable equilibrium, and discuss its implications for Hoyle-Lyttleton accretion onto a luminous star. When the Eddington sphere is present, the cross-section of a compact star for actual accretion is typically less than the geometrical cross-section πR2, direct infall onto the stellar surface only being possible for relativistic particles, with the required minimum particle velocity at infinity typically about half the speed of light. We further show that particles on typical trajectories in the vicinity of the stellar surface will also be trapped on the Eddington capture sphere.

Sidansvarig: Webbredaktion|Sidan uppdaterades: 2012-09-11
Dela:

På Göteborgs universitet använder vi kakor (cookies) för att webbplatsen ska fungera på ett bra sätt för dig. Genom att surfa vidare godkänner du att vi använder kakor.  Vad är kakor?