Activity Report for WG3 (Gravitational Physics), NewCompStar 2016

Activity Report for WG3 (Gravitational Physics), NewCompStar 2016. Working Group Leader: D I Jones (Southampton)

2016 saw the announcement of the first ever detection gravitational waves. This was an exciting year for WG3, as evidenced by the activity below.

The topic leaders appointed previously remained in place. These are Bruno Giacomazzo (Trento, Italy), with topic “numerical modelling of binary inspiral”; Tanja Hinderer (Albert Einstein Institute, Golm, Germany), with topic “Influence of EoS on gravitational wave signals from inspiral”; Andreas Bauswein (Thessaloniki, Greece), with topic “Binary inspiral electromagnetic counterparts/ejecta”; and Leonardo Gualtieri (Rome, Italy), with topic “Gravitational wave emission from individual stars”.

There were several relevant working group meetings. The Relativistic Astrophysics Group of the University of Alicante, Spain, hosted a WG1-WG3 workshop with main topic: “Origin, evolution and observable effects of the magnetic field in neutron stars”. The meeting will took place from the 13th to 15th of April 2016. The Gravity Group of the University of Southampton hoisted a WG1-WG3 meeting on the theme “Oscillations and instabilities in neutron stars”, 13-14 September 2016. There were 35 participants, with all three working groups being well represented.

The 2016 NewCompStar School took place at the University of Coimbra, 5-9 September 2016. It was dedicated to gravitational issues, with theme “Neutron stars: gravitational physics theory and observations”.

Gravitational issues were well represented at the annual main meeting, which in 2016 took place in Istanbul, with many talks having a dominantly gravitational theme. These included talks on gravitational wave emission from spinning and oscillating stars, gravitational wave emission from binary coalescence, neutron stars in alternative theories of gravity, and the motion of compact objects around supermassive black holes.

In terms of STSMs, there were several with a strongly gravity-related theme, and many more where gravity played an important role. These included a project on pipeline development using high-performance computing for gravitational wave detection, a project on the huge-gravity duality, and the equilibria of self-gravitating tori.

Several outreach articles dealing with gravitational wave issues were written and posted on the main NewCompStar website, including articles “I-Love-Q: universality in properties of neutron stars” and “Gravitaiotnal Waves”.

In terms of publications, there were many with a significant gravity-component that acknowledged NewCompStar. Some relevant publications include:

“Extraction of gravitational waves in numerical relativity”, N. T. Bishop and L. Rezzolla, Living Rev Relativ 19 (2016) 2

“Exploring properties of high-density matter through remnants of neutron-star mergers”, Bauswein, Andreas; Stergioulas, Nikolaos; Janka, Hans-Thomas, EPJA 52 56 (2016)

“Gravitational-wave signal from binary neutron stars: A systematic analysis of the spectral properties”, Luciano Rezzolla and Kentaro Takami, Phys. Rev. D 93, 124051 (2016)

“Observationally constraining gravitational wave emission from short gamma-ray burst remnants “, Paul D. Lasky Kostas Glampedakis, MNRAS 458 2(2016)

“Is the Gravitational-Wave Ringdown a Probe of the Event Horizon?”, Vitor Cardoso, Edgardo Franzin, and Paolo Pani, Phys. Rev. Lett. 116, 171101 (2016)

“General relativistic magnetohydrodynamic simulations of binary neutron star mergers with the APR4 equation of state”, A Endrizzi, R Ciolfi, B Giacomazzo, W Kastaun and T Kawamura, Classical and Quantum Gravity 33 16 (2016)