We present the results of the first joint search for gravitational-wave bursts by the LIGO and GEO600 detectors. We search for bursts with characteristic central frequencies in the band 768 to 2048 Hz in the data acquired between the 22nd of February and the 23rd of March, 2005 (fourth LSC Science Run - S4). We discuss the inclusion of the GEO600 data in the Waveburst-CorrPower pipeline that first searches for coincident excess power events without taking into account differences in the antenna responses or strain sensitivities of the various detectors. We compare the performance of this pipeline to that of the coherent Waveburst pipeline based on the maximum likelihood statistic. This likelihood statistic is derived from a coherent sum of the detector data streams that takes into account the antenna patterns and sensitivities of the different detectors in the network. We find that the coherentWaveburst pipeline is sensitive to signals of amplitude 30 - 50% smaller than the Waveburst-CorrPower pipeline. We perform a search for gravitational-wave bursts using both pipelines and find no detection candidates in the S4 data set when all four instruments were operating stably.
We present recent results from searches by the LIGO Science Collaboration for bursts of gravitational-wave radiation, as well as the status of other ongoing searches. These include directed searches for bursts associated with observed sources (gamma-ray bursts, soft gamma repeaters) and untriggered searches for bursts from unknown sources. We also present the status of some newer investigations, such as coherent network methods. We show methods for interpreting our search results in terms of astrophysical source distributions that improve their accessibility to the wider community.
We report on a search for gravitational wave bursts in data from the three LIGO interferometric detectors during their third science run. The search targets subsecond bursts in the frequency range 100-1100 Hz for which no waveform model is assumed, and has a sensitivity in terms of the root-sum-square (rss) strain amplitude of hrss ~ 10^{-20} / sqrt(Hz). No gravitational wave signals were detected in the 8 days of analyzed data.
We report on a search for gravitational wave bursts using data from the first science run of the LIGO detectors. Our search focuses on bursts with durations ranging from 4 ms to 100 ms, and with significant power in the LIGO sensitivity band of 150 to 3000 Hz. We bound the rate for such detected bursts at less than 1.6 events per day at 90% confidence level. This result is interpreted in terms of the detection efficiency for ad hoc waveforms (Gaussians and sine-Gaussians) as a function of their root-sum-square strain h_{rss}; typical sensitivities lie in the range h_{rss} ~ 10^{-19} - 10^{-17}…
We present an all-sky search for gravitational waves in the frequency range 1 to 6 kHz during the first calendar year of LIGO's fifth science run. This is the first untriggered LIGO burst analysis to be conducted above 3 kHz. We discuss the unique properties of interferometric data in this regime. 161.3 days of triple-coincident data were analyzed. No gravitational events above threshold were observed and a frequentist upper limit of 5.4 events per year on the rate of strong gravitational wave bursts was placed at a 90% confidence level. Implications for specific theoretical models of gravitat…
The burst search in LIGO relies on the coincident detection of transient signals in multiple interferometers. As only minimal assumptions are made about the event waveform or duration, the analysis pipeline requires loose coincidence in time, frequency and amplitude. Confidence in the resulting events and their waveform consistency is established through a time-domain coherent analysis: the r-statistic test. This paper presents a performance study of the r-statistic test for triple coincidence events in the second LIGO Science Run (S2), with emphasis on its ability to suppress the background f…
One of the brightest Gamma Ray Burst ever recorded, GRB030329, occurred during the second science run of the LIGO detectors. At that time, both interferometers at the Hanford, WA LIGO site were in lock and acquiring data. The data collected from the two Hanford detectors was analyzed for the presence of a gravitational wave signal associated with this GRB. This paper presents a detailed description of the search algorithm implemented in the current analysis.
We examine the benefits of performing a joint LIGO--Virgo search for transient signals. We do this by adding burst and inspiral signals to 24 hours of simulated detector data. We find significant advantages to performing a joint coincidence analysis, above either a LIGO only or Virgo only search. These include an increased detection efficiency, at a fixed false alarm rate, to both burst and inspiral events and an ability to reconstruct the sky location of a signal.
We discuss the relevance, for the search of gravitational-wave bursts, of upper limits on the total mass loss of the Galaxy which come from various astronomical observations. For sub-millisecond bursts we obtain limits on the event rate, as a function of the GW amplitude, which are stronger than the corresponding upper limits set by LIGO in the S2 run. A detection of a burst rate saturating these limits, with the sensitivities of present and near-future runs, would imply that, with some improvement on the accuracy of astronomical observations of the Galaxy, as foreseen with the GAIA mission, i…
We present results from an all-sky search for unmodeled gravitational-wave bursts in the data collected by the LIGO, GEO 600 and Virgo detectors between November 2006 and October 2007. The search is performed by three different analysis algorithms over the frequency band 50-6000 Hz. Data are analyzed for times with at least two of the four LIGO-Virgo detectors in coincident operation, with a total live time of 266 days. No events produced by the search algorithms survive the selection cuts. We set a frequentist upper limit on the rate of gravitational-wave bursts impinging on our network of de…
A number of different methods have been proposed to identify unanticipated burst sources of gravitational waves in data arising from LIGO and other gravitational wave detectors. When confronted with such a wide variety of methods one is moved to ask if they are all necessary, i.e. given detector data that is assumed to have no gravitational wave signals present, do they generally identify the same events with the same efficiency, or do they each 'see' different things in the detector? Here we consider three different methods, which have been used within the LIGO Scientific Collaboration as par…
We present a comparative study of 6 search methods for gravitational wave bursts using simulated LIGO and Virgo noise data. The data's spectra were chosen to follow the design sensitivity of the two 4km LIGO interferometers and the 3km Virgo interferometer. The searches were applied on replicas of the data sets to which 8 different signals were injected. Three figures of merit were employed in this analysis: (a) Receiver Operator Characteristic curves, (b) necessary signal to noise ratios for the searches to achieve 50 percent and 90 percent efficiencies, and (c) variance and bias for the esti…
We describe the plans for a joint search for unmodelled gravitational wave bursts being carried out by the LIGO and TAMA collaborations using data collected during February-April 2003. We take a conservative approach to detection, requiring candidate gravitational wave bursts to be seen in coincidence by all four interferometers. We focus on some of the complications of performing this coincidence analysis, in particular the effects of the different alignments and noise spectra of the interferometers.
The LIGO detectors collected about 4 months of data in 2003-2004 during two science runs, S2 and S3. Several environmental and auxiliary channels that monitor the instruments' physical environment and overall interferometric operation were analyzed in order to establish the quality of the data as well as the presence of transients of non-astrophysical origin. This analysis allowed better understanding of the noise character of the instruments and the establishment of correlations between transients in these channels and the one recording the gravitational wave strain. In this way vetoes for sp…
The fourth science run of the LIGO and GEO 600 gravitational-wave detectors, carried out in early 2005, collected data with significantly lower noise than previous science runs. We report on a search for short-duration gravitational-wave bursts with arbitrary waveform in the 64-1600 Hz frequency range appearing in all three LIGO interferometers. Signal consistency tests, data quality cuts, and auxiliary-channel vetoes are applied to reduce the rate of spurious triggers. No gravitational-wave signals are detected in 15.5 days of live observation time; we set a frequentist upper limit of 0.15 pe…
We report on the first joint search for gravitational waves by the TAMA and LIGO collaborations. We looked for millisecond-duration unmodelled gravitational-wave bursts in 473 hr of coincident data collected during early 2003. No candidate signals were found. We set an upper limit of 0.12 events per day on the rate of detectable gravitational-wave bursts, at 90% confidence level. From simulations, we estimate that our detector network was sensitive to bursts with root-sum-square strain amplitude above approximately 1-3x10^{-19} Hz^{-1/2} in the frequency band 700-2000 Hz. We describe the detai…
The search procedure for burst gravitational waves has been studied using 24 hours of simulated data in a network of three interferometers (Hanford 4-km, Livingston 4-km and Virgo 3-km are the example interferometers). Several methods to detect burst events developed in the LIGO Scientific Collaboration (LSC) and Virgo collaboration have been studied and compared. We have performed coincidence analysis of the triggers obtained in the different interferometers with and without simulated signals added to the data. The benefits of having multiple interferometers of similar sensitivity are demonst…
We perform a search for gravitational wave bursts using data from the second science run of the LIGO detectors, using a method based on a wavelet time-frequency decomposition. This search is sensitive to bursts of duration much less than a second and with frequency content in the 100-1100Hz range. It features significant improvements in the instrument sensitivity and in the analysis pipeline with respect to the burst search previously reported by LIGO. Improvements in the search method allow exploring weaker signals, relative to the detector noise floor, while maintaining a low false alarm rat…
We present the results obtained from an all-sky search for gravitational-wave (GW) bursts in the 64-2000 Hz frequency range in data collected by the LIGO detectors during the first year (November 2005 - November 2006) of their fifth science run. The total analyzed livetime was 268.6 days. Multiple hierarchical data analysis methods were invoked in this search. The overall sensitivity expressed in terms of the root-sum-square (rss) strain amplitude h_{rss} for gravitational-wave bursts with various morphologies was in the range of 6 times 10^{-22} Hz^{-1/2} to a few times 10^{-21} Hz^{-1/2}. No…
The first simultaneous operation of the AURIGA detector and the LIGO observatory was an opportunity to explore real data, joint analysis methods between two very different types of gravitational wave detectors: resonant bars and interferometers. This paper describes a coincident gravitational wave burst search, where data from the LIGO interferometers are cross-correlated at the time of AURIGA candidate events to identify coherent transients. The analysis pipeline is tuned with two thresholds, on the signal-to-noise ratio of AURIGA candidate events and on the significance of the cross-correlat…
In this paper we describe the performance of the WaveBurst algorithm which was designed for detection of gravitational wave bursts in interferometric data. The performance of the algorithm was evaluated on the test data set collected during the second LIGO Scientific run. We have measured the false alarm rate of the algorithm as a function of the threshold and estimated its detection efficiency for simulated burst waveforms.
This brief report describes the search for gravitational-wave inspiral signals from short gamma-ray bursts. Since these events are probably created by the merger of two compact objects, a targeted search with a lower threshold can be made. The data around 22 short gamma-ray bursts have been analyzed.
Short Gamma Ray Bursts (SGRB) are believed to originate from the merger of two compact objects. If this scenario is correct, SGRB will be accompanied by the emission of strong gravitational waves, detectable by current or planned GW detectors, such as LIGO and Virgo. No detection of a gravitational wave has been made up to date. In this paper I will use a set of SGRB with observed redshifts to fit a model describing the cumulative number of SGRB as a function of redshift, to determine the rate of such merger events in the nearby universe. These estimations will be used to make probability stat…
We have performed a search for bursts of gravitational waves associated with the very bright Gamma Ray Burst GRB030329, using the two detectors at the LIGO Hanford Observatory. Our search covered the most sensitive frequency range of the LIGO detectors (approximately 80-2048 Hz), and we specifically targeted signals shorter than 150 ms. Our search algorithm looks for excess correlated power between the two interferometers and thus makes minimal assumptions about the gravitational waveform. We observed no candidates with gravitational wave signal strength larger than a pre-determined threshold.…
We investigate the detectability of massive mode of polarization of Gravitational Waves (GWs) in f(R) theory of gravity associated with Gamma Ray Bursts (GRBs) sources. We obtain the beam pattern function of Laser Interferometric Gravitational wave Observatory (LIGO) corresponding to the massive polarization of GWs and perform Bayesian analysis to study this polarization. It is found that the massive polarization component with a mass of 10^-22eV/c2 is too weak to be detected at LIGO with its current configuration.
We develop here algorithms which allow to find regimes of signal-recycled Fabry-Perot--Michelson interferometer (for example, Advanced LIGO), optimized concurrently for two (binary inspirals + bursts) and three (binary inspirals + bursts + millisecond pulsars) types of gravitational waves sources. We show that there exists a relatevely large area in the interferometer parameters space where the detector sensitivity to the first two kinds of sources differs only by a few percent from the maximal ones for each kind of source. In particular, there exists a specific regime where this difference is…
This paper presents a search for generic short-duration gravitational-wave (GW) transients (or GW bursts) in the data from the third observing run of Advanced LIGO and Advanced Virgo. We use coherent WaveBurst (cWB) pipeline enhanced with a decision-tree classification algorithm for more efficient separation of GW signals from noise transients. The machine-learning (ML) algorithm is trained on a representative set of noise events and a set of simulated stochastic signals that are not correlated with any known signal model. This training procedure preserves the model-independent nature of the s…
Mergers of two compact objects, like two neutron stars or a neutron star and a black hole, are the probable progenitor of short gamma-ray bursts. These events are also promising sources of gravitational waves, that are currently motivating related searches by an international network of gravitational wave detectors. Here we describe a search for gravitational waves from the in-spiral phase of two coalescing compact objects, in coincidence with short GRBs occurred during during LIGO's fifth science run and Virgo's first science run. The search includes 22 GRBs for which data from more than one …
We search for coincident gravitational wave signals from inspiralling neutron star binaries using LIGO and TAMA300 data taken during early 2003. Using a simple trigger exchange method, we perform an inter-collaboration coincidence search during times when TAMA300 and only one of the LIGO sites were operational. We find no evidence of any gravitational wave signals. We place an observational upper limit on the rate of binary neutron star coalescence with component masses between 1 and 3 M_sun of 49 per year per Milky Way equivalent galaxy at a 90% confidence level. The methods developed during …
The weak equivalence principle (WEP) is the cornerstone of gravitational theories. At the local scale, WEP has been tested to high accuracy by various experiments. On the intergalactic distance scale, WEP could be tested by comparing the arrival time of different messengers emitted from the same source. The gravitational time delay caused by massive galaxies is proportional to $γ+1$, where the parameter $γ$ is unity in general relativity. The values of $γ$ for different massless particles should be different if WEP is violated, i.e., $Δγ$ is used to indicate the deviation from WEP. So far, $|Δ…
Presented in this paper is a detailed and direct comparison of the LIGO and Virgo binary neutron star detection pipelines. In order to test the search programs, numerous inspiral signals were added to 24 hours of simulated detector data. The efficiencies of the different pipelines were tested, and found to be comparable. Parameter estimation routines were also tested. We demonstrate that there are definite benefits to be had if LIGO and Virgo conduct a joint coincident analysis; these advantages include increased detection efficiency and the providing of source sky location information.
Gamma-ray bursts are believed to originate in core-collapse of massive stars. This produces an active nucleus containing a rapidly rotating Kerr black hole surrounded by a uniformly magnetized torus represented by two counter-oriented current rings. We quantify black hole spin-interactions with the torus and charged particles along open magnetic flux-tubes subtended by the event horizon. A major output of Egw=4e53 erg is radiated in gravitational waves of frequency fgw=500 Hz by a quadrupole mass-moment in the torus. Consistent with GRB-SNe, we find (i) Ts=90s (tens of s, Kouveliotou et al. 19…
We present the results of a search for short-duration gravitational-wave bursts associated with 39 gamma-ray bursts (GRBs) detected by gamma-ray satellite experiments during LIGO's S2, S3, and S4 science runs. The search involves calculating the crosscorrelation between two interferometer data streams surrounding the GRB trigger time. We search for associated gravitational radiation from single GRBs, and also apply statistical tests to search for a gravitational-wave signature associated with the whole sample. For the sample examined, we find no evidence for the association of gravitational ra…
Magnetars are neutron stars with exceptionally strong dipole magnetic fields which are observed to display a range of x-ray flaring behavior, but the flaring mechanism is not well understood. The third observing run of Advanced LIGO and Virgo extended from April 1, 2019 to March 27, 2020, and contained x-ray flares from known magnetar SGR 1935+2154, as well as the newly-discovered magnetar, Swift J1818-1607. We search for gravitational waves coincident with these magnetar flares with minimally modeled, coherent searches which specifically target both short-duration gravitational waves produced…
We present the status of the joint search for gravitational waves from inspiraling neutron star binaries in the LIGO Science Run 2 and TAMA300 Data Taking Run 8 data, which was taken from February 14 to April 14, 2003, by the LIGO and TAMA collaborations. In this paper we discuss what has been learned from an analysis of a subset of the data sample reserved as a ``playground''. We determine the coincidence conditions for parameters such as the coalescence time and chirp mass by injecting simulated Galactic binary neutron star signals into the data stream. We select coincidence conditions so as…
Coalescing binaries in distant galaxies are one of the most promising sources of gravitational waves detectable by the LIGO project.$^{[1-5]}$ They are also a copious source of neutrinos,$^{[1]}$ however these neutrino pulses are far too weak to be detected on earth. Several years ago Eichler \etal$\,$$^{[6]}$ suggested that they are also sources of $γ$-ray bursts (GRBs). Recently it was found$^{[7]}$ that GRBs are likely to be cosmological in origin, and coalescing binary systems$^{[6,8-11]}$ are probably the most promising cosmological sources. The current estimates of the burst and LIGO rat…
Progenitors of short gamma-ray bursts are thought to be neutron stars coalescing with their companion black hole or neutron star, which are one of the main gravitational wave sources. We have devised a Bayesian framework for combining gamma-ray burst and gravitational wave information that allows us to probe short gamma-ray burst luminosities. We show that combined short gamma-ray burst and gravitational wave observations not only improve progenitor distance and inclination angle estimates, they also allow the isotropic luminosities of short gamma-ray bursts to be determined without the need f…
Gravitational Wave (GW) burst detection algorithms typically rely on the hypothesis that the burst signal is "locally stationary", that is it changes slowly with frequency. Under this assumption, the signal can be decomposed into a small number of wavelets with constant frequency. This justifies the use of a family of sine-Gaussian templates in the Omega pipeline, one of the algorithms used in LIGO-Virgo burst searches. However there are plausible scenarios where the burst frequency evolves rapidly, such as in the merger phase of a binary black hole and/or neutron star coalescence. In those ca…
We analyze the gravitational wave signatures of a network of metastable cosmic strings. We consider the case of cosmic string instability to breakage, with no primordial population of monopoles. This scenario is well motivated from GUT and string theoretic models with an inflationary phase below the GUT/string scale. The network initially evolves according to a scaling solution, but with breakage events resulting from confined monopoles (beads) being pair produced and accelerated apart. We find these ultra-relativistic beads to be a potent source of gravitational waves bursts, detectable by In…
The Advanced LIGO and Virgo experiments are poised to detect gravitational waves (GWs) directly for the first time this decade. The ultimate prize will be joint observation of a compact binary merger in both gravitational and electromagnetic channels. However, GW sky locations that are uncertain by hundreds of square degrees will pose a challenge. I describe a real-time detection pipeline and a rapid Bayesian parameter estimation code that will make it possible to search promptly for optical counterparts in Advanced LIGO. Having analyzed a comprehensive population of simulated GW sources, we d…
The LIGO Scientific Collaboration (LSC) is developing and running analysis pipelines to search for gravitational-wave transients emitted by astrophysical events such as compact binary mergers or core-collapse supernovae. However, because of the non-Gaussian, non-stationary nature of the noise exhibited by the LIGO detectors, residual false alarms might be found at the end of the pipelines. A critical aspect of the search is then to assess our confidence for gravitational waves and to distinguish them from those false alarms. Both the 'Compact Binary Coalescence' and the 'Burst' working groups …
Advanced LIGO and Advanced Virgo are expected to make the first direct detections of gravitational waves (GW) in the next several years. Possible types of GW emission include short-duration bursts, signals from the coalescence of compact binaries consisting of neutron stars or black holes, continuous radiation from fast-spinning neutron stars, and stochastic background radiation of a primordial nature or resulting from the superposition of a large number of individually unresolvable sources. We describe the different approaches that have been developed to search for these different types of si…
We study prospects of a method to constrain the inclination of a coalescing compact binary by detecting its gravitational waves associated with a three-dimensionally localized (direction and distance) short-hard gamma-ray burst. We take advantage of a synergy of these two observations, and our method can be applied even with a single interferometer. For a nearly face-on binary the inclination angle $I$ can be constrained in the range 1-1/SNR < cosI \le 1 (SNR: the signal to noise ratio of gravitational wave detection), provided that the error of the distance estimation is negligible. This meth…
Short gamma-ray bursts are believed to originate from the merger of two compact objects. If this scenario is correct, these bursts will be accompanied by the emission of strong gravitational waves, detectable by current or planned GW detectors, such as LIGO and Virgo. No detection of a gravitational wave has been made up to date. In this paper I will use a set of observed redshift measurements of short gamma-ray bursts to fit a model in order to determine the rate of such merger events in the nearby universe. Various corrections will be included in that calculation, as the field-of-view of the…
LIGO Laboratory（LIGO实验室）；California Institute of Technology（加州理工学院）
One class of gravitational wave signals LIGO is searching for consists of short duration bursts of unknown waveforms. Potential sources include core collapse supernovae, gamma ray burst progenitors, and mergers of binary black holes or neutron stars. We present a density-based clustering algorithm to improve the performance of time-frequency searches for such gravitational-wave bursts when they are extended in time and/or frequency, and not sufficiently well known to permit matched filtering. We have implemented this algorithm as an extension to the QPipeline, a gravitational-wave data analysi…
The first detection of a binary neutron star merger, GW170817, and an associated short gamma-ray burst confirmed that neutron star mergers are responsible for at least some of these bursts. The prompt gamma ray emission from these events is thought to be highly relativistically beamed. We present a method for inferring limits on the extent of this beaming by comparing the number of short gamma-ray bursts observed electromagnetically to the number of neutron star binary mergers detected in gravitational waves. We demonstrate that an observing run comparable to the expected Advanced LIGO 2016--2…
Autonomous gravitational-wave searches -- fully automated analyses of data that run without human intervention or assistance -- are desirable for a number of reasons. They are necessary for the rapid identification of gravitational-wave burst candidates, which in turn will allow for follow-up observations by other observatories and the maximum exploitation of their scientific potential. A fully automated analysis would also circumvent the traditional "by hand" setup and tuning of burst searches that is both labourious and time consuming. We demonstrate a fully automated search with X-Pipeline,…
Compact binary coalescence (CBC) is one of the most promising sources of gravitational waves. These sources are usually searched for with matched filters which require accurate calculation of the GW waveforms and generation of large template banks. We present a complementary search technique based on algorithms used in un-modeled searches. Initially designed for detection of un-modeled bursts, which can span a very large set of waveform morphologies, the search algorithm presented here is constrained for targeted detection of the smaller subset of CBC signals. The constraint is based on the as…
We report on the status of the Laser Interferometric Gravitational-Wave Observatory (LIGO) and the plans and progress towards Enhanced and Advanced LIGO. The initial LIGO detectors have finished a two year long data run during which a full year of triple-coincidence data was collected at design sensitivity. Much of this run was also coincident with the data runs of interferometers in Europe, GEO600 and Virgo. The joint analysis of data from this international network of detectors is ongoing. No gravitational wave signals have been detected in analyses completed to date. Currently two of the LI…
We describe how the six planned detectors (2 LIGOs, VIRGO, GEO, AIGO, TAMA) can be used to perform coincidence experiments for the detection of broadband signals from either coalescing compact binaries or burst sources. We make comparisons of the achievable sensitivities of these detectors under different optical configurations and find that a meaningful coincidence experiment for the detection of coalescing binary signals can only be performed by a network where the LIGOs and VIRGO are operated in power recycling mode and other medium scale detectors are operated in dual recycling mode. For t…
Detection of gravitational waves (GW) from highly eccentric binary black hole (BBH) systems can provide insight into their dynamics and formation. To date, all of the LIGO-Virgo BBH detections have been made using quasi-circular templates in their initial discovery. However, recent studies have found some of these systems to be compatible with high eccentricity in the LIGO band, $e_{10 \textrm{Hz}} > 0.1$, possibly pointing to a population of sources that are challenging to detect. Current low-latency search methods used with ground-based GW detector data are not well equipped to detect highly…
The nature of fast radio bursts (FRBs) remains enigmatic. Highly energetic radio pulses of millisecond duration, FRBs are observed with dispersion measures consistent with an extragalactic source. A variety of models have been proposed to explain their origin. One popular class of theorized FRB progenitor is the coalescence of compact binaries composed of neutron stars and/or black holes. Such coalescence events are strong gravitational-wave emitters. We demonstrate that measurements made by the LIGO and Virgo gravitational-wave observatories can be leveraged to severely constrain the validity…
Using the observed rate of short-duration gamma-ray bursts (GRBs) it is possible to make predictions for the detectable rate of compact binary coalescences in gravitational-wave detectors. These estimates rely crucially on the growing consensus that short gamma-ray bursts are associated with the merger of two neutron stars or a neutron star and a black hole, but otherwise make no assumptions beyond the observed rate of short GRBs. In particular, our results do not assume coincident gravitational wave and electromagnetic observations. We show that the non-detection of mergers in the existing LI…
Gravitational waves from precessing binary black holes exhibit new features that are absent in non-precessionary systems. All current waveform models take into account only the modulation of the signal due to precession. In this letter, we find that this effect has its own signature, by gravitational emission of a short and transient signal, or burst. The frequency of the burst is comparable to that of the late stage of the inspiral. We show that under certain conditions, this signal is strong enough to be detected by Advanced LIGO. For third-generation detectors like the Einstein telescope, t…
The LIGO-Virgo collaboration uses a variety of techniques to detect and characterize gravitational waves. One approach is to use templates - models for the signals derived from Einstein's equations. Another approach is to extract the signals directly from the coherent response of the detectors in LIGO-Virgo network. Both approaches played an important role in the first gravitational wave detections. Here we extend the BayesWave analysis algorithm, which reconstructs gravitational wave signals using a collection of continuous wavelets, to use a generalized wavelet family, known as chirplets, th…
We discuss data analysis techniques that can be used in the search for gravitational wave bursts from cosmic strings. When data from multiple interferometers are available, we describe consistency checks that can be used to greatly reduce the false alarm rates. We construct an expression for the rate of bursts for arbitrary cosmic string loop distributions and apply it to simple known solutions. The cosmology is solved exactly and includes the effects of a late-time acceleration. We find substantially lower burst rates than previous estimates suggest and explain the disagreement. Initial LIGO …
