The link between short Gamma-ray bursts and Gravitational Waves: perspectives for the THESEUS mission
P. D'Avanzo
备注：
To be published in the Proceedings of the THESEUS Workshop 2017 (http://www.isdc.unige.ch/theseus/workshop2017.html), Journal of the Italian Astronomical Society (Mem.SAIt), Editors L. Amati, E. Bozzo, M. Della Valle, D. Gotz, P. O'Brien. Details on the THESEUS mission concept can be found in the white paper Amati et al. 2017 (arXiv:171004638) and Stratta et al. 2017 (arXiv:1712.08153)
The knowledge of the class of short Gamma-Ray Bursts (GRBs), characterised by a duration of the gamma-ray emission $\leq 2$ s, experienced an impressive boost in the last decade. In particular, the discovery of short GRB afterglows in 2005 with Swift and HETE-II provided the first insight into their energy scale, environments and host galaxies. The lack of detection of associated supernovae proved that they are not related to the death of massive stars. The increasing evidence for compact object binary progenitors makes short GRBs one of the most promising sources of gravitational waves for the forthcoming Advanced LIGO/Virgo science runs. To this end, the spectacular detection of the first electromagnetic counterpart of the gravitational wave event GW\,170817 originated by the coalescence of a double neutron star (NS) system, represents a first hystorical milestone. The (weak) short GRB\,170817A associated to this GW event provided the long-sought evidence that at least a fraction of short GRBs are originated by NS-NS merging and suggested the intriguing possibility that relativistic jets can be launched in the process of a NS-NS merger. The THESEUS mission, thanks to the diversity of intstrumentation, fast pointing and flexible schedule will represent a key facility in the multi-messenger astronomy era.
We will discuss the observing strategy of the Transient High Energy Sky and Early Universe Surveyor (THESEUS) mission proposed to ESA as a response to the M5 call for proposals. The description of THESEUS and its science goals can be found in the white paper by Amati et al. (2017).
The class of long gamma-ray bursts (LGRBs) is associated with the collapse of the most massive stars, making them a tool to investigate star formation in the early Universe. Furthermore, thanks to their exceptional brightness, LGRB afterglows can be used as extra-galactic background sources capable of unveiling the properties of the cold/warm gas of their hosting galaxies, up to the highest redshifts. Therefore LGRBs allow, uniquely, the combination of the information on different phases of the gas, through the absorption lines present in the afterglow spectra and the emission (continuum and l…
The Transient High-Energy Sky and Early Universe Surveyor (THESEUS) is a mission concept developed in the last years by a large European consortium, with interest in prospective participation by research groups in USA and other non-European countries. As detailed in Amati et al. 2017 (arXiv:1710.04638) and Stratta et al. 2017 (arXiv:1712.08153), THESEUS aims at exploiting high-redshift Gamma-Ray Bursts for getting unique clues on the early Universe and, being an unprecedentedly powerful machine for the detection, accurate location and redshift determination of all types of GRBs (long, short, h…
Modern Multimessenger Astronomy is a powerful instrument for performing cosmological crucial tests of the Standard Cosmological Model in the wide redshift interval up to $z \sim 10$. This is principally important for discussion related to discrepancies between local and global measurements of cosmological parameters. We present a review of multimessenger gamma-ray burst observations currently conducted and planed for THESEUS$-$BTA cooperative program. Such observations give a unique opportunity to test the fundamental foundations of cosmological models: gravitation theory; cosmological princip…
The recent discovery of the electromagnetic counterpart of the gravitational wave source GW170817, has demonstrated the huge informative power of multi-messenger observations. During the next decade the nascent field of multi-messenger astronomy will mature significantly. Around 2030, third generation gravitational wave detectors will be roughly ten times more sensitive than the current ones. At the same time, neutrino detectors currently upgrading to multi km^3 telescopes, will include a 10 km^3 facility in the Southern hemisphere that is expected to be operational around 2030. In this review…
Through a series of simulated observations, we investigate the capability of the instruments aboard the forthcoming THESEUS mission for the detection of a characteristic signal from decaying dark matter (DM) in the keV-MeV energy range. We focus our studies on three well studied Standard Model extensions hosting axion-like particle, dark photon, and sterile neutrino DM candidates. We show that, due to the sensitivity of THESEUS' X and Gamma Imaging Spectrometer (XGIS) instrument, existing constraints on dark matter parameters can be improved by a factor of up to ~300, depending on the consider…
The Transient High Energy Sky and Early Universe Surveyor (THESEUS) is a space mission concept aimed at exploiting Gamma-Ray Bursts for investigating the early Universe and at providing a substantial advancement of multi-messenger and time-domain astrophysics. A fundamental contribution to achieve this goal will be provided by the powerful synergy between THESEUS and the extremely large ground-based telescopes which will operate in the next decade, like E-ELT. We discuss great improvements coming from this joint effort and describe some possible observing scenarios.
Recent advances in fitting prompt emission spectra in gamma-ray bursts (GRBs) are boosting our understanding of the still elusive origin of this radiation. These progresses have been possible thanks to a more detailed analysis of the low-energy part ($<$\,100\,keV) of the prompt spectrum, where the spectral shape is sometimes found to deviate from a simple power-law shape. This deviation is well described by a spectral break or, alternatively by the addition of a thermal component. Spectral data extending down to less than 1\,keV are extremely relevant for these studies, but presently they are…
The Transient High-Energy Sky and Early Universe Surveyor (THESEUS) is a mission concept developed in the last years by a large European consortium and currently under study by the European Space Agency (ESA) as one of the three candidates for next M5 mission (launch in 2032). THESEUS aims at exploiting high-redshift GRBs for getting unique clues to the early Universe and, being an unprecedentedly powerful machine for the detection, accurate location (down to arcsec) and redshift determination of all types of GRBs (long, short, high-z, under-luminous, ultra-long) and many other classes of tran…
The radiation process of GRB prompt emission remains highly debated till date. Though a smoothly broken powerlaw function like Band provides an excellent fit to most of the cases, a spectrum with a broad top or double hump structure has emerged recently for several GRBs, specifically for the bright ones that have high signal to noise data. A number of models have been proposed to capture this shape which includes an additional blackbody component along with the Band, or a double smoothly broken powerlaw, or two blackbodies with a powerlaw/cut-off powerlaw and so on. However, finding the statis…
The Hercules-Corona Borealis Great Wall is a statistically significant clustering of gamma-ray bursts around redshift 2. Motivated by recent theoretical results indicating that a maximal Universal structure size may indeed coincide with its estimated size (2-3Gpc), we reexamine the question of this Great Wall's existence from both observational and theoretical perspectives. Our statistical analyses confirm the clustering's presence in the most reliable data set currently available, and we present a video showing what this data set looks like in~3D. Cosmological explanations (i.e. having to do …
Ultra-light primordial black holes (PBHs) in the mass range of 10$^{16}$ - 10$^{22}$ g are allowed by current observations to constitute a significant fraction, if not all, of the dark matter in the Universe. In this work, we present limits on ultra-light, non-rotating PBHs which arise from the non-detection of the Hawking radiation signals from such objects in the keV-MeV energy band. Namely, we consider observations from the current-generation missions XMM-Newton and INTEGRAL/SPI and discuss the observational perspectives of the future missions Athena, eXTP, and THESEUS for PBH searches. Bas…
THESEUS is a space mission concept aimed at exploiting Gamma-Ray Bursts for investigating the early Universe and at providing a substantial advancement of multi-messenger and time-domain astrophysics. These goals will be achieved through a unique combination of instruments allowing GRB and X-ray transient detection over a broad field of view (more than 1sr) with 0.5-1 arcmin localization, an energy band extending from several MeV down to 0.3 keV and high sensitivity to transient sources in the soft X-ray domain, as well as on-board prompt (few minutes) follow-up with a 0.7 m class IR telescope…
The multi-wavelength detection of GW170817 has inaugurated multi-messenger astronomy. The next step consists in interpreting observations coming from population of gravitational wave sources. We introduce saprEMo, a tool aimed at predicting the number of electromagnetic signals characterised by a specific light curve and spectrum, expected in a particular sky survey. By looking at past surveys, saprEMo allows us to constrain models of electromagnetic emission or event rates. Applying saprEMo to proposed astronomical missions/observing campaigns provides a perspective on their scientific impact…
Future missions for long gammma-ray burst (GRB) observations at high redshift such as HiZ-GUNDAM and THESEUS will provide clue to the star formation history in our universe. In this paper focusing on high redshift (z>8) GRBs, we calculate the detection rate of long GRBs by future observations, considering both Population (Pop) I&II stars and Pop III stars as GRB progenitors. For the Pop I&II star formation rate (SFR), we adopt an up-to-date model of high-redshift SFR based on the halo mass function and dark matter accretion rate obtained from cosmological simulations. We show that the Pop I&II…
The Chinese CubeSat Mission, Gamma Ray Integrated Detectors (GRID), recently detected its first gamma-ray burst, GRB 210121A, which was jointly observed by the Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor (GECAM). This burst is confirmed by several other missions, including \fermi and \textit{Insight}-HXMT. We combined multi-mission observational data and performed a comprehensive analysis of the burst's temporal and spectral properties. Our results show that the burst is relatively special in its high peak energy, thermal-like low energy indices, and large fluenc…
Type I X-ray bursts and superbursts from accreting neutron stars illuminate the accretion disk and produce a reflection signal that evolves as the burst fades. Examining the evolution of reflection features in the spectra will give insight into the burst-disk interaction, a potentially powerful probe of accretion disk physics. At present, reflection has been observed during only two bursts of exceptional duration. We investigate the detectability of reflection signatures with four of the latest well-studied X-ray observatory concepts: Hitomi, NICER, Athena, and LOFT. Burst spectra are modeled …
I present an overview of the Swift mission, which was launched on November 20, 2004 to discover and observe the most energetic of astrophysical phenomena, gamma-ray bursts (GRBs). After almost 6 years in space the Observatory is in excellent shape, with all systems and instruments performing nominally and in burst chasing mode for an average of 97% of the time. Swift is also a multi-purpose multi-frequency mission with the observing time evolving from mostly GRB targets, to mainly secondary science ones such as supernovae, cataclysmic variables and novae, active galactic nuclei, Galactic trans…
Ultra-long gamma-ray bursts (ULGRBs) have very atypical durations of more than 2000 seconds. Even if their origins are discussed, the SVOM mission with its soft gamma-ray telescope ECLAIRs could detect ULGRBs and increase the sample of the few which have been detected so far by the Burst Alert Telescope aboard the Neil Gehrels Swift Observatory and some other instruments. In this paper, after a short description of the SVOM mission, we present methods developed to clean detector images from non-flat background and known source contributions in the onboard imaging process. We present an estimat…
The X-ray emission of gamma-ray bursts (GRBs) is often characterized by an initial steep decay, followed by a nearly constant emission phase (so called "plateau") which can extend up to thousands of seconds. While the steep decay is usually interpreted as the tail of the prompt gamma-ray flash, the long-lasting plateau is commonly associated to the emission from the external shock sustained by energy injection from a long lasting central engine. A recent study proposed an alternative interpretation, ascribing both the steep decay and the plateau to high-latitude emission (HLE) from a "structur…
This is a White Paper in support of the mission concept of the Large Observatory for X-ray Timing (LOFT), proposed as a medium-sized ESA mission. We discuss the potential of LOFT for the study of thermonuclear X-ray bursts on accreting neutron stars. For a summary, we refer to the paper.
This is a White Paper in support of the mission concept of the Large Observatory for X-ray Timing (LOFT), proposed as a medium-sized ESA mission. We discuss the potential of LOFT for the study of gamma-ray bursts. For a summary, we refer to the paper.
We examine the prospects of the high redshift Long Gamma Ray Bursts (LGRB) Hubble Diagram as a test of the basic cosmological principles. Analysis of the Hubble Diagram allows us to test several fundamental cosmological principles using the directly observed flux-distance-redshift relation. Modern LGRB data, together with the correlation between the spectral peak energy and the isotropic-equivalent radiated energy (the so-called Amati relation) can be used for construction of the Hubble Diagram at the model-independent level. We emphasise observational selection effects, which inevitably exist…
We present a short review of GRB studies performed for many years by Ioffe Institute experiments onboard a number of space missions. The first breakthrough in the studies of GRB was made possible by four Konus experiments carried out by the Ioffe Institute onboard the Venera 11-14 deep space missions from 1978 to 1983. A new important stage of our research is associated with the joint Russian-American experiment with the Russian Konus scientific instrument onboard the U.S. Wind spacecraft which has been successfully operating since its launch in November 1994. The Konus-Wind experiment has mad…
Despite being a general observatory, and not a Gamma-Ray Bursts (GRBs) oriented mission, INTEGRAL has contributed to several important discoveries in the GRB field. This has been obtained thanks to its unprecedented localization capabilities, and sensitivity in the soft gamma-ray domain. In this paper I will review the main results obtained during the last 10 years with, and thanks to, INTEGRAL GRBs, including the discovery of one of the few GRBs spectroscopically associated with a Supernova, the first measurement of variable polarization in the GRB prompt emission, the indication of the exist…
Observations of Gamma-Ray Bursts with the Fermi Large Area Telescope have prompted theoretical advances and posed big challenges in the understanding of such extreme sources, despite the fact that GRB emission above 100 MeV is a fairly rare event. The first Fermi/LAT GRB catalog, published a year ago, presented 28 detections out of ~300 bursts detected by the Fermi Gamma-Ray Burst Monitor (GBM) within the LAT field of view. Building on the results from that work and on recent development in the understanding of the systematic errors on GBM localizations, we developed a new detection algorithm …
The Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope observatory is a pair conversion telescope sensitive to gamma-rays over more than four energy decades, between 20 MeV and more than 300 GeV. Acting in synergy with the Gamma-ray Burst Monitor (GBM) - the other instrument onboard the mission - the LAT features unprecedented sensitivity for the study of gamma-ray bursts (GRBs) in terms of spectral coverage, effective area, and instrumental dead time. We will review the main results from Fermi-LAT observation of GRB, presenting the main properties of GRBs at GeV energies.
Gamma-ray Bursts (GRBs) prompt emission spectra are often fitted with the empirical ''Band" function, namely two power laws smoothly connected. The typical slope of the low energy (sub-MeV) power law is $α_{B}\simeq -1$. In a small fraction of long GRBs this power law splits into two components such that the spectrum presents, in addition to the typical $\sim$ MeV $νF_ν$ peak, a break at the order of a few keV or hundreds keV. The typical power law slopes below and above the break are -0.6 and -1.5 respectively. If the break is a common feature, the value of $α_{B}$ could be an ''average'' of …
The Sonoma State University (SSU) Education and Public Outreach (E/PO) group leads the Swift Education and Public Outreach program. For Swift, we have previously implemented broad efforts that have contributed to NASA's Science Mission Directorate E/PO portfolio across many outcome areas. Our current focus is on highly-leveraged and demonstrably successful activities, including the wide-reaching Astrophysics Educator Ambassador program, and our popular websites: Epo's Chronicles and the Gamma-ray Burst (GRB) Skymap. We also make major contributions working collaboratively through the Astrophys…
BurstCube will detect long GRBs, attributed to the collapse of massive stars, short GRBs (sGRBs), resulting from binary neutron star mergers, as well as other gamma-ray transients in the energy range 10-1000 keV. sGRBs are of particular interest because they are predicted to be the counterparts of gravitational wave (GW) sources soon to be detectable by LIGO/Virgo. BurstCube contains 4 CsI scintillators coupled with arrays of compact low-power Silicon photomultipliers (SiPMs) on a 6U Dellingr bus, a flagship modular platform that is easily modifiable for a variety of 6U CubeSat architectures. …
After seven years of science operation, the Fermi mission has brought great advances in the study of Gamma-ray Bursts (GRBs). Over 1600 GRBs have been detected by the Gamma-ray Burst Monitor, and more than 100 of these are also detected by the Large Area Telescope above 30 MeV. We will give an overview of these observations, presenting the common properties in the GRB temporal and spectral behavior at high energies. We will also highlight the unique characteristics of some individual bursts. The main physical implications of these results will be discussed, along with open questions regarding …
We present motivations for and study feasibility of a small, rapid optical to IR response gamma ray burst (GRB) space observatory. By analyzing existing GRB data, we give realistic detection rates for X-ray and optical/IR instruments of modest size under actual flight conditions. Given new capabilities of fast optical/IR response (about 1 s to target) and simultaneous multi-band imaging, such an observatory can have a reasonable event rate, likely leading to new science. Requiring a Swift-like orbit, duty cycle, and observing constraints, a Swift-BAT scaled down to 190 square cm of detector ar…
In this paper we first review the results obtained by the INTEGRAL mission in the domain of Gamma-Ray Bursts (GRBs), thanks to the INTEGRAL Burst Alert System, which is able to deliver near real-time alerts for GRBs detected within the IBIS field of view. More than 120 GRBs have been detected to date and we summarize their properties here. In the second part of this review we focus on the polarimetric results obtained by IBIS and SPI on GRBs and Galactic compact objects.
Simultaneous, precise measurements of the mass $M$ and radius $R$ of neutron stars can yield uniquely valuable information about the still uncertain properties of cold matter at several times the density of nuclear matter. One method that could be used to measure $M$ and $R$ is to analyze the energy-dependent waveforms of the X-ray flux oscillations seen during some thermonuclear bursts from some neutron stars. These oscillations are thought to be produced by X-ray emission from hotter regions on the surface of the star that are rotating at or near the spin frequency of the star. Here we explo…
We review more than 10 years of continuous monitoring of accreting X-ray pulsars with the all-sky Gamma-ray Burst Monitor (GBM) aboard the Fermi Gamma-ray Space Telescope. Our work includes data from the start of GBM operations in August 2008, through to November 2019. Pulsations from 39 accreting pulsars are observed over an energy range of $10-50\,$keV by GBM. The GBM Accreting Pulsars Program (GAPP) performs data reduction and analysis for each accreting pulsar and makes histories of the pulse frequency and pulsed flux publicly available. We examine in detail the spin histories, outbursts a…
The Fermi observatory, with its Gamma-Ray Bursts monitor (GBM) and Large Area Telescope (LAT), is observing Gamma-ray Bursts with unprecedented spectral coverage and sensitivity, from ~10 keV to > 300 GeV. In the first 3 years of the mission it observed emission above 100 MeV from 35 GRBs, an order of magnitude gain with respect to previous observations in this energy range. In this paper we review the main results obtained on such sample, highlighting also the relationships with the low-energy features (as measured by the GBM), and with measurements from observatories at other wavelengths. We…
The Neutron Star Interior Composition Explorer (NICER) has observed seven thermonuclear X-ray bursts from the Low Mass X-ray Binary (LMXB) neutron star 4U 1728-34 from the start of the mission's operations until February of 2019. Three of these bursts show oscillations in their decaying tail with frequencies that are within 1 Hz of the previously detected burst oscillations from this source. Two of these burst oscillations have unusual properties: They have large fractional rms amplitudes of $ 48 \pm 9 \%$ and $ 46 \pm 9 \%$, and they are detected only at photon energies above 6 keV. By contra…
Long Gamma Ray Bursts (LGRBs) can be used to address key questions on the formation of the modern universe including: How does the star formation rate evolve at high redshift? When and how did the intergalactic medium become re-ionized? What processes governed its early chemical enrichment? A LGRB signals when a massive star collapses to form a black hole and in doing so provides an independent tracer of the star formation rate. The LGRB afterglow is a bright back-light to view the host galaxy and intergalactic medium in absorption. The Gamow Explorer will be optimized to search for high redsh…
Quantum Convolutional Neural Networks for the detection of Gamma-Ray Bursts in the AGILE space mission data
University of Bologna（博洛尼亚大学）；INAF/OAS Bologna（意大利国家天体物理研究所/博洛尼亚天体物理与空间科学天文台）；German Research Center for Artificial Intelligence (DFKI)（德国人工智能研究中心）；Università degli Studi di Modena e Reggio Emilia（摩德纳和雷焦艾米利亚大学）；Department of Physics and Astronomy, University of Bologna（博洛尼亚大学物理与天文学系）；INAF/OA Roma（意大利国家天体物理研究所/罗马天文台）；ASI/SSDC Roma（意大利航天局/罗马空间科学数据中心）；INAF/IAPS Roma（意大利国家天体物理研究所/罗马行星际与空间物理研究所）；INAF/IRA Bologna（意大利国家天体物理研究所/博洛尼亚射电天文研究所）；INAF/OA Catania（意大利国家天体物理研究所/卡塔尼亚天文台）；INAF/OA Trieste（意大利国家天体物理研究所/的里雅斯特天文台）
Since its successful launch in June 2008, the {\it Fermi} Gamma-ray Space Telescope has made important breakthroughs in the understanding of the Gamma-Ray Burst (GRB) phenomemon. The combination of the GBM and the LAT instruments onboard the {\it Fermi} observatory has provided a wealth of information from its observations of GRBs over seven decades in energy. We present brief descriptions of the {\it Fermi} instruments and their capabilities for GRB science, and report highlights from {\it Fermi} observations of high-energy prompt and extended GRB emission. The main physical implications of t…
Long-duration gamma-ray burst (GRB) afterglow observations offer cutting-edge opportunities to characterise the star formation history of the Universe back to the epoch of reionisation, and to measure the chemical composition of interstellar and intergalactic gas through absorption spectroscopy. The main barrier to progress is the low efficiency in rapidly and confidently identifying which bursts are high redshift ($z > 5$) candidates before they fade, as this requires low-latency follow-up observations at near-infrared wavelengths (or longer) to determine a reliable photometric redshift estim…
We aim to obtain high-quality time-resolved spectral fits of gamma-ray bursts (GRBs) observed by the Gamma-ray Burst Monitor (GBM) on board the Fermi Gamma-ray Space Telescope. We perform time-resolved spectral analysis with high temporal and spectral resolution of the brightest bursts observed by Fermi GBM in its first 4 years of mission. We present the complete catalog containing 1,491 spectra from 81 bursts with high spectral and temporal resolution. Distributions of parameters, statistics of the parameter populations, parameter-parameter and parameter-uncertainty correlations, and their ex…
High-redshift Gamma-Ray Bursts (GRBs) beyond redshift $\sim6$ are potentially powerful tools to probe the distant early Universe. Their detections in large numbers and at truly high redshifts call for the next generation of high-energy wide-field instruments with unprecedented sensitivity at least one order of magnitude higher than the ones currently in orbit. On the other hand, follow-up observations of the afterglows of high-redshift GRBs and identification of their host galaxies, which would be difficult for the currently operating telescopes, require new, extremely large facilities of at m…
Revisiting holographic dark energy from the perspective of multi-messenger gravitational wave astronomy: future joint observations with short gamma-ray bursts
Ultra-long Gamma-Ray Bursts (ulGRBs) are Gamma-Ray Bursts (GRBs) with an unusually long emission in X and gamma rays, reaching durations of thousands of seconds. They could form a specific class of high-energy transient events, whose origin is still under discussion. The current sample of known ulGRBs consists of a few tens of events which have been detected so far by the Burst Alert Telescope (BAT) aboard the Neil Gehrels Swift Observatory and some other instruments. The SVOM mission which is scheduled to begin operations after 2021 could help to detect and observe more ulGRBs thanks to its s…
