Multimodal Analysis of Gravitational Wave Signals and Gamma-Ray Bursts from Binary Neutron Star Mergers

A major boost in the understanding of the universe was given by the revelation of the first coalescence event of two neutron stars (GW170817) and the observation of the same event across the entire electromagnetic spectrum. With third-generation gravitational wave detectors and the new astronomical facilities, we expect many multi-messenger events of the same type. We anticipate the need to analyse the data provided to us by such events not only to fulfil the requirements of real-time analysis, but also in order to decipher the event in its entirety through the information emitted in the different messengers using machine learning. We propose a change in the paradigm in the way we do multi-messenger astronomy, simultaneously using the complete information generated by violent phenomena in the Universe. What we propose is the application of a multimodal machine learning approach to characterize these events.

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Progress Toward a Space-Based Gravitational Wave Observatory

Proceedings of the International Astronomical Union ◽

10.1017/s1743921316005524 ◽

2015 ◽

Vol 11 (A29B) ◽

pp. 357-362

Author(s):

Jeffrey C. Livas ◽

Robin T. Stebbins

Keyword(s):

Gravitational Wave ◽

Gravitational Waves ◽

Gamma Ray ◽

European Space Agency ◽

Gravity Gradient ◽

Electromagnetic Spectrum ◽

Space Agency ◽

Pulsar Timing ◽

The Universe ◽

Gamma Ray Telescopes

AbstractThe discovery of binary pulsar PSR 1913+16 by Hulse & Taylor in 1974 established the existence of gravitational waves, for which the 1983 Nobel Prize was awarded. However, the measurement of astrophysical parameters from gravitational waves will open an entirely new spectrum for discovery and understanding of the Universe, not simply a new window in the electromagnetic spectrum like gamma ray telescopes in the 1970s. Two types of ground-based detectors, Advanced LIGO/Virgo and Pulsar Timing Arrays, are expected to directly detect gravitational waves in their respective frequency bands before the end of the decade. However, many of the most exciting sources are in the band from 0.1–100 mHz, accessible only from space due to seismic and gravity gradient noise on Earth. The European Space Agency (ESA) has chosen the 'Gravitational Universe' as the science theme for its L3 Cosmic Visions opportunity, planned for launch in 2034. NASA is planning to participate as a junior partner. Here we summarize progress toward realizing a gravitational wave observatory in space.

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Hunting Gravitational Waves with Multi-Messenger Counterparts: Australia’s Role

Publications of the Astronomical Society of Australia ◽

10.1017/pasa.2015.49 ◽

2015 ◽

Vol 32 ◽

Cited By ~ 9

Author(s):

E. J. Howell ◽

A. Rowlinson ◽

D. M. Coward ◽

P. D. Lasky ◽

D. L. Kaplan ◽

...

Keyword(s):

Gravitational Wave ◽

Gamma Ray ◽

Cosmic Ray ◽

High Energy ◽

Design Sensitivity ◽

Electromagnetic Spectrum ◽

New Era ◽

Worldwide Network ◽

The Universe

AbstractThe first observations by a worldwide network of advanced interferometric gravitational wave detectors offer a unique opportunity for the astronomical community. At design sensitivity, these facilities will be able to detect coalescing binary neutron stars to distances approaching 400 Mpc, and neutron star–black hole systems to 1 Gpc. Both of these sources are associated with gamma-ray bursts which are known to emit across the entire electromagnetic spectrum. Gravitational wave detections provide the opportunity for ‘multi-messenger’ observations, combining gravitational wave with electromagnetic, cosmic ray, or neutrino observations. This review provides an overview of how Australian astronomical facilities and collaborations with the gravitational wave community can contribute to this new era of discovery, via contemporaneous follow-up observations from the radio to the optical and high energy. We discuss some of the frontier discoveries that will be made possible when this new window to the Universe is opened.

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Gravitational waves from mountains in newly born millisecond magnetars

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab307 ◽

2021 ◽

Vol 502 (4) ◽

pp. 4680-4688

Author(s):

Ankan Sur ◽

Brynmor Haskell

Keyword(s):

Gravitational Wave ◽

Gravitational Waves ◽

Massive Star ◽

Gamma Ray ◽

Dipole Radiation ◽

X Ray ◽

Binary Neutron Star ◽

Spin Period ◽

Lower Maximum ◽

Wave Emission

ABSTRACT In this paper, we study the spin-evolution and gravitational-wave luminosity of a newly born millisecond magnetar, formed either after the collapse of a massive star or after the merger of two neutron stars. In both cases, we consider the effect of fallback accretion; and consider the evolution of the system due to the different torques acting on the star, namely the spin-up torque due to accretion and spin-down torques due to magnetic dipole radiation, neutrino emission, and gravitational-wave emission linked to the formation of a ‘mountain’ on the accretion poles. Initially, the spin period is mostly affected by the dipole radiation, but at later times, accretion spin the star up rapidly. We find that a magnetar formed after the collapse of a massive star can accrete up to 1 M⊙, and survive on the order of 50 s before collapsing to a black hole. The gravitational-wave strain, for an object located at 1 Mpc, is hc ∼ 10−23 at kHz frequencies, making this a potential target for next-generation ground-based detectors. A magnetar formed after a binary neutron star merger, on the other hand, accretes at the most 0.2 M⊙ and emits gravitational waves with a lower maximum strain of the order of hc ∼ 10−24, but also survives for much longer times, and may possibly be associated with the X-ray plateau observed in the light curve of a number of short gamma-ray burst.

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A three-dimensional laser interferometer gravitational-wave detector

Scientific Reports ◽

10.1038/s41598-020-72850-6 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Mengxu Liu ◽

Biping Gong

Keyword(s):

Gravitational Wave ◽

Laser Interferometer ◽

Three Dimensional ◽

Electromagnetic Emission ◽

Laser Interferometry ◽

Electromagnetic Spectrum ◽

Spherically Symmetric ◽

Directional Response ◽

Wave Detector ◽

The Universe

Abstract The gravitational wave (GW) has opened a new window to the universe beyond the electromagnetic spectrum. Since 2015, dozens of GW events have been caught by the ground-based GW detectors through laser interferometry. However, all the ground-based detectors are L-shaped Michelson interferometers, with very limited directional response to GW. Here we propose a three-dimensional (3-D) laser interferometer detector in the shape of a regular triangular pyramid, which has more spherically symmetric antenna pattern. Moreover, the new configuration corresponds to much stronger constraints on parameters of GW sources, and is capable of constructing null-streams to get rid of the signal-like noise events. A 3-D detector of kilometer scale of such kind would shed new light on the joint search of GW and electromagnetic emission.

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Exploring Binary-Neutron-Star-Merger Scenario of Short-Gamma-Ray Bursts by Gravitational-Wave Observation

Physical Review Letters ◽

10.1103/physrevlett.104.141101 ◽

2010 ◽

Vol 104 (14) ◽

Cited By ~ 53

Author(s):

Kenta Kiuchi ◽

Yuichiro Sekiguchi ◽

Masaru Shibata ◽

Keisuke Taniguchi

Keyword(s):

Neutron Star ◽

Gravitational Wave ◽

Gamma Ray ◽

Gamma Ray Bursts ◽

Binary Neutron Star ◽

Wave Observation

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The Swift satellite lives up to its name, revealing cosmic explosions as they happen

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2008.0153 ◽

2008 ◽

Vol 366 (1884) ◽

pp. 4393-4404 ◽

Cited By ~ 2

Author(s):

Rhaana L.C Starling

Keyword(s):

Gamma Radiation ◽

Gamma Ray ◽

Massive Stars ◽

Gamma Ray Bursts ◽

Electromagnetic Spectrum ◽

Distant Galaxies ◽

The 1960S ◽

Cosmic Explosions ◽

The Universe

Gamma-ray bursts are the most powerful objects in the Universe. Discovered in the 1960s as brief flashes of gamma radiation, we now know that they emit across the entire electromagnetic spectrum, are located in distant galaxies and comprise two distinct populations, one of which may originate in the deaths of massive stars. The launch of the Swift satellite in 2004 brought a flurry of new discoveries, advancing our understanding of these sources and the galaxies that host them. I highlight a number of important results from the Swift era thus far.

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Towards Improving the Prospects for Coordinated Gravitational-Wave and Electromagnetic Observations

Proceedings of the International Astronomical Union ◽

10.1017/s1743921312001068 ◽

2011 ◽

Vol 7 (S285) ◽

pp. 358-360 ◽

Cited By ~ 2

Author(s):

Ilya Mandel ◽

Luke Z. Kelley ◽

Enrico Ramirez-Ruiz

Keyword(s):

Gravitational Wave ◽

Prior Information ◽

Gamma Ray ◽

Optimal Parameter ◽

Gamma Ray Bursts ◽

Binary Neutron Star ◽

Quantitative Estimates ◽

Optimal Parameter Estimation ◽

Parameter Estimation Techniques

AbstractWe discuss two approaches to searches for gravitational-wave (GW) and electromagnetic (EM) counterparts of binary neutron-star mergers. The first approach relies on triggering archival searches of GW detector data based on detections of EM transients. Quantitative estimates of the improvement to GW detector reach due to the increased confidence in the presence and parameters of a signal from a binary merger gained from the EM transient suggest utilizing other transients in addition to short gamma-ray bursts. The second approach involves following up GW candidates with targeted EM observations. We argue for the use of slower but optimal parameter-estimation techniques and for a more sophisticated use of astrophysical prior information, including galaxy catalogues to find preferred follow-up locations.

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Data-driven Expectations for Electromagnetic Counterpart Searches Based on LIGO/Virgo Public Alerts

The Astrophysical Journal ◽

10.3847/1538-4357/ac366d ◽

2022 ◽

Vol 924 (2) ◽

pp. 54

Author(s):

Polina Petrov ◽

Leo P. Singer ◽

Michael W. Coughlin ◽

Vishwesh Kumar ◽

Mouza Almualla ◽

...

Keyword(s):

Data Analysis ◽

Neutron Star ◽

Gravitational Wave ◽

Gamma Ray ◽

Data Driven ◽

Wave Localization ◽

Localization Accuracy ◽

Binary Neutron Star ◽

Data Release

Abstract Searches for electromagnetic counterparts of gravitational-wave signals have redoubled since the first detection in 2017 of a binary neutron star merger with a gamma-ray burst, optical/infrared kilonova, and panchromatic afterglow. Yet, one LIGO/Virgo observing run later, there has not yet been a second, secure identification of an electromagnetic counterpart. This is not surprising given that the localization uncertainties of events in LIGO and Virgo’s third observing run, O3, were much larger than predicted. We explain this by showing that improvements in data analysis that now allow LIGO/Virgo to detect weaker and hence more poorly localized events have increased the overall number of detections, of which well-localized, gold-plated events make up a smaller proportion overall. We present simulations of the next two LIGO/Virgo/KAGRA observing runs, O4 and O5, that are grounded in the statistics of O3 public alerts. To illustrate the significant impact that the updated predictions can have, we study the follow-up strategy for the Zwicky Transient Facility. Realistic and timely forecasting of gravitational-wave localization accuracy is paramount given the large commitments of telescope time and the need to prioritize which events are followed up. We include a data release of our simulated localizations as a public proposal planning resource for astronomers.

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