[seminar] Astro Journal Club on 30 March

[Oskari Miettinen]

Dear all,

Our Astro Journal Club will be held on Wednesday at 3:00 pm (sharp) in the
seminar room F-201 of the Physics Department. This time we will discuss
about the recent first direct detection of gravitational waves.

Presenter: Vibor Jelic
Paper title: Observation of Gravitational Waves from a Binary Black Hole
Merger
Authors: Abbott, B. P., Abbott, R., Abbott, T. D., et al.
Paper status: Published in Physical Review Letters, Volume 116, Issue 6
(2016)

Summary:
On September 14, 2015 at 09:50:45 UTC the two detectors of the Laser
Interferometer Gravitational-Wave Observatory simultaneously observed a
transient gravitational-wave signal. The signal sweeps upwards in
frequency from 35 to 250 Hz with a peak gravitational-wave strain of
1.0×10-21. It matches the waveform predicted by general relativity for the
inspiral and merger of a pair of black holes and the ringdown of the
resulting single black hole. The signal was observed with a matched-filter
signal-to-noise ratio of 24 and a false alarm rate estimated to be less
than 1 event per 203 000 years, equivalent to a significance greater than
5.1sigma. The source lies at a luminosity distance of 410(-180,+160) Mpc
corresponding to a redshift z =0.09(-0.04,+0.03). In the source frame, the
initial black hole masses are 36(-4,+5) Msun and 29(-4,+4) Msun, and the
final black hole mass is 62(-4,+4) Msun, with 3.0(-0.5,+0.5) Msunxc2
radiated in gravitational waves. All uncertainties define 90% credible
intervals. These observations demonstrate the existence of binary
stellar-mass black hole systems. This is the first direct detection of
gravitational waves and the first observation of a binary black hole
merger.

Links to the paper:

http://adsabs.harvard.edu/abs/2016PhRvL.116f1102A

https://physics.aps.org/featured-article-pdf/10.1103/PhysRevLett.116.061102

Hope to see you all on Wednesday!

Cheers,
Oskari