SEMINAR: Forecasting Gamma-Ray Bursts using Gravitational Waves

SEMINAR: Forecasting Gamma-Ray Bursts using Gravitational Waves

Speaker: Sarp Akçay

Title: Forecasting Gamma-Ray Bursts using Gravitational Waves

Date/Time: October 14, 2018 / 13:40 - 14:30

Place: FENS L063


Abstract: We explore the intriguing possibility of employing future ground-based gravitational-wave interferometers to detect the inspiral of binary neutron stars sufficiently early to alert electromagnetic observatories so that a gamma-ray burst (GRB) can be observed in its entirety from its very beginning. We quantify the ability to predict a GRB by computing the time a binary neutron star (BNS) system takes to inspiral from its moment of detection to its final merger. We define the moment of detection to be the instant at which the interferometer network accumulates a signal-to-noise ratio of 15. For our computations, we specifically consider BNS systems at luminosity distances of (i) D≤200Mpc for the three-interferometer Advanced-LIGO-Virgo network of 2020, and (ii) D≤1000Mpc for Einstein Telescope's B and C configurations. In the case of Advanced LIGO-Virgo we find that we may at best get a few minutes of warning time, thus we expect no forecast of GRBs in the 2020s. On the other hand, Einstein Telescope will provide us with advance warning times of more than five hours for D≤100Mpc. Taking one hour as a benchmark advance warning time, we obtain a corresponding range of roughly 600 Mpc for the Einstein Telescope C configuration. Using current BNS merger event rates within this volume, we show that Einstein C will forecast  100 GRBs in the 2030s. We reapply our warning-time computation to binary black hole - neutron star inspirals and find 1 to 3 tidal disruption events to be forecast by the same detector.

Bio: I am currently a postdoctoral research fellow at the Theoretical Physics Institute at Friedrich-Schiller Universitat Jena. I got my Ph.D. from the University of Texas at Austin in 2009.I was an IRC postdoc and then a lecturer at University College Dublin (UCD). I have additionally done two postdocs at the University of Southampton in the UK and was twice hosted at the Institut des Hautes Etudes Scientifiques in Paris. In 2014, I won the Irish Research Council Fellowship and moved to UCD. I have been doing research in general relativity since ca. 2005. Some of my interests are: causal boundaries of spacetimes and black holes, cosmological black hole solutions, gravitational-wave astronomy, source modelling for the future space-based LISA detector, gravitational self-force approach, and its synergies with post-Newtonian and effective-one-body theories.

Contact: Erdinç Öztürk& Emre Erdem& Emre Özlü& Semih Onur Sezer