Archive for Merging black holes

Three New Publications at the Open Journal of Astrophysics

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , on April 27, 2024 by telescoper

It’s time for the usual  Saturday roundup of business at the  Open Journal of Astrophysics. The latest batch of publications consists of three papers, taking the count in Volume 7 (2024) up to 30 and the total published by OJAp up to 145.

First one up is “Baryonic Imprints on DM Halos: the concentration-mass relation and its dependence on halo and galaxy properties” .  The authors, Mufan Shao and Dhayaa Anbajagane of the University of Chicago, USA, use  a non-linear model informed by simulations to study the imprint of galaxy formation physics on the concentration-mass relationship using various different choices of halo selection criteria. This one is in the folder marked Astrophysics of Galaxies and was published on 24th April 2024.

Here is a screen grab of the overlay, which includes the abstract:

 

You can read the paper directly on arXiv here.

The second paper to announce is “Variability in SSTc2d J163134.1-240100, a brown dwarf with quasi-spherical mass loss” which describes a search for variability in a brown dwarf star known to be losing mass and the implications of the lack thereof for the reason for the outflow therefrom. The authors are Aleks Scholz (St Andrews, UK),  Koraljka Muzic (Lisbon, Portugal), Victor Almendros-Abad (Palermo, Italy), Antonella Natta (DIAS, Ireland), Dary Ruiz-Rodriguez (NRAO, USA), Lucas Cieza (Uni. Diego Portales, Chile), Cristina Rodriguez-Lopez (IAA-CSIC, Granada, Spain)

This one is in the folder Solar and Stellar Astrophysics and was also published on 24th April 2024. The overlay looks like this:

 

You can read this paper directly on the arXiv here.

The last paper of this batch, also in the folder marked Astrophysics of Galaxies, is  entitled “MAGICS I. The First Few Orbits Encode the Fate of Seed Massive Black Hole Pairs”  and is a computational study of the process by which massive black holes are formed by merging smaller seed black holes. It was published on April 26th 2024 (i.e. yesterday). The authors are: Nianyi Chen, Diptajyoti Mukherjee and Tiziana Di Matteo (all Carnegie Mellon University); Yueying Ni (Harvard); Simeon Bird (University of California, Riverside); and Rupert Croft (Carnegie Mellon University). All authors are based in the USA.

Here is a screengrab of the overlay:

 

To read the accepted version of this on the arXiv please go here.
That’s all for now. More news in a week or so!

 

 

And then there were five….

Posted in The Universe and Stuff with tags , , , , , , on November 17, 2017 by telescoper

…black hole mergers detected via gravitational waves, that is. Here are the key measurements for Number 5, codename GW170608. More information can be found here.

Here is the abstract of the discovery paper:

On June 8, 2017 at 02:01:16.49 UTC, a gravitational-wave signal from the merger of two stellar-mass black holes was observed by the two Advanced LIGO detectors with a network signal-to-noise ratio of 13. This system is the lightest black hole binary so far observed, with component masses 12+7-2 M⊙ and 7+2-2 M⊙ (90% credible intervals). These lie in the range of measured black hole masses in low-mass X-ray binaries, thus allowing us to compare black holes detected through gravitational waves with electromagnetic observations. The source’s luminosity distance is 340 +140-140Mpc, corresponding to redshift 0.07+0.03-0.03. We verify that the signal waveform is consistent with the predictions of general relativity.

This merger seems to have been accompanied by a lower flux of press releases than previous examples…