[seminar] Astro Journal Club on June 14th

[Lana Ceraj]

Dear all, 

Astro Journal club continues this Wednesday at 3 p.m. (sharp) in the seminar room F-201 of the Physics Department. 

Presenter: Krešimir Tisanić, mag. phys.

Authors: Hees et al. (2017)

Title of presentation: Testing General Relativity with Stellar Orbits around the Supermassive Black Hole in Our Galactic Centre

Abstract: 
We demonstrate that short-period stars orbiting around the supermassive black hole in our Galactic center can successfully be used to probe the gravitational theory in a strong regime. We use 19 years of observations of the two best measured short-period stars orbiting our Galactic center to constrain a hypothetical fifth force that arises in various scenarios motivated by the development of a unification theory or in some models of dark matter and dark energy. No deviation from general relativity is reported and the fifth force strength is restricted to an upper 95% confidence limit of |α|<0.016 at a length scale of λ=150 astronomical units. We also derive a 95% confidence upper limit on a linear drift of the argument of periastron of the short-period star S0-2 of |˙ωS0-2|<1.6×10−3  rad/yr, which can be used to constrain various gravitational and astrophysical theories. This analysis provides the first fully self-consistent test of the gravitational theory using orbital dynamic in a strong gravitational regime, that of a supermassive black hole. A sensitivity analysis for future measurements is also presented.

Link to paper: https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.118.211101 <https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.118.211101>

If you have recently read interesting astrophysics paper you would like to present, please contact me via e-mail: lceraj at phy.hr <mailto:lceraj at phy.hr>

See you on Wednesday.

Cheers,
Lana
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.phy.pmf.unizg.hr/pipermail/seminar/attachments/20170612/c68639e0/attachment.html>