Showing papers by "G. Gemme published in 2010"
University of Glasgow1, University of Salerno2, Max Planck Society3, University of Southampton4, University of Paris-Sud5, Paris Diderot University6, VU University Amsterdam7, University of Nice Sophia Antipolis8, Washington State University9, University of Warsaw10, University of Birmingham11, Cardiff University12, University of Rome Tor Vergata13, Moscow State University14, California Institute of Technology15, fondazione bruno kessler16, Centre national de la recherche scientifique17, University of Cambridge18, University of Tübingen19, University of Urbino20, University of Vienna21, University of Minnesota22, University of Jena23, Albert Einstein Institution24, Northwestern University25, University of Savoy26, Pennsylvania State University27, University of Pisa28, Sapienza University of Rome29, University of Florence30
TL;DR: The third-generation ground-based observatory Einstein Telescope (ET) project as discussed by the authors is currently in its design study phase, and it can be seen as the first step in this direction.
Abstract: Advanced gravitational wave interferometers, currently under realization, will soon permit the detection of gravitational waves from astronomical sources. To open the era of precision gravitational wave astronomy, a further substantial improvement in sensitivity is required. The future space-based Laser Interferometer Space Antenna and the third-generation ground-based observatory Einstein Telescope (ET) promise to achieve the required sensitivity improvements in frequency ranges. The vastly improved sensitivity of the third generation of gravitational wave observatories could permit detailed measurements of the sources' physical parameters and could complement, in a multi-messenger approach, the observation of signals emitted by cosmological sources obtained through other kinds of telescopes. This paper describes the progress of the ET project which is currently in its design study phase.
1,497 citations
TL;DR: In this paper, Kalogera et al. presented an up-to-date summary of the rates for all types of compact binary coalescence sources detectable by the initial and advanced versions of the ground-based gravitational-wave detectors LIGO and Virgo.
Abstract: We present an up-to-date, comprehensive summary of the rates for all types of compact binary coalescence sources detectable by the initial and advanced versions of the ground-based gravitational-wave detectors LIGO and Virgo. Astrophysical estimates for compact-binary coalescence rates depend on a number of assumptions and unknown model parameters and are still uncertain. The most confident among these estimates are the rate predictions for coalescing binary neutron stars which are based on extrapolations from observed binary pulsars in our galaxy. These yield a likely coalescence rate of 100 Myr−1 per Milky Way Equivalent Galaxy (MWEG), although the rate could plausibly range from 1 Myr−1 MWEG−1 to 1000 Myr−1 MWEG−1 (Kalogera et al 2004 Astrophys. J. 601 L179; Kalogera et al 2004 Astrophys. J. 614 L137 (erratum)). We convert coalescence rates into detection rates based on data from the LIGO S5 and Virgo VSR2 science runs and projected sensitivities for our advanced detectors. Using the detector sensitivities derived from these data, we find a likely detection rate of 0.02 per year for Initial LIGO–Virgo interferometers, with a plausible range between 2 × 10−4 and 0.2 per year. The likely binary neutron–star detection rate for the Advanced LIGO–Virgo network increases to 40 events per year, with a range between 0.4 and 400 per year.
1,011 citations
TL;DR: In this article, the authors present an up-to-date summary of the rates for all types of compact binary coalescence sources detectable by the Initial and Advanced versions of the ground-based LIGO and Virgo Astrophysical estimates for compact-binary coalescence rates depend on a number of assumptions and unknown model parameters.
Abstract: We present an up-to-date, comprehensive summary of the rates for all types of compact binary coalescence sources detectable by the Initial and Advanced versions of the ground-based gravitational-wave detectors LIGO and Virgo Astrophysical estimates for compact-binary coalescence rates depend on a number of assumptions and unknown model parameters, and are still uncertain The most confident among these estimates are the rate predictions for coalescing binary neutron stars which are based on extrapolations from observed binary pulsars in our Galaxy These yield a likely coalescence rate of 100 per Myr per Milky Way Equivalent Galaxy (MWEG), although the rate could plausibly range from 1 per Myr per MWEG to 1000 per Myr per MWEG We convert coalescence rates into detection rates based on data from the LIGO S5 and Virgo VSR2 science runs and projected sensitivities for our Advanced detectors Using the detector sensitivities derived from these data, we find a likely detection rate of 002 per year for Initial LIGO-Virgo interferometers, with a plausible range between 00002 and 02 per year The likely binary neutron-star detection rate for the Advanced LIGO-Virgo network increases to 40 events per year, with a range between 04 and 400 per year
918 citations
University of Glasgow1, University of Salerno2, Max Planck Society3, University of Southampton4, University of Paris-Sud5, VU University Amsterdam6, University of Nice Sophia Antipolis7, Washington State University8, University of Zielona Góra9, University of Birmingham10, Cardiff University11, University of Rome Tor Vergata12, Moscow State University13, California Institute of Technology14, fondazione bruno kessler15, Centre national de la recherche scientifique16, University of Cambridge17, University of Tübingen18, University of Urbino19, University of Vienna20, University of Minnesota21, University of Jena22, Northwestern University23, University of Savoy24, Pennsylvania State University25, University of Pisa26, Sapienza University of Rome27, Roma Tre University28, University of Florence29
TL;DR: The status of the project Einstein Telescope (ET), a design study of a third-generation gravitational wave observatory, is reported in this paper, where an overview of the possible science reaches and the technological progress needed to realize a third generation observatory are discussed.
Abstract: Large gravitational wave interferometric detectors, like Virgo and LIGO, demonstrated the capability to reach their design sensitivity, but to transform these machines into an effective observational instrument for gravitational wave astronomy a large improvement in sensitivity is required. Advanced detectors in the near future and third-generation observatories in more than one decade will open the possibility to perform gravitational wave astronomical observations from the Earth. An overview of the possible science reaches and the technological progress needed to realize a third-generation observatory are discussed in this paper. The status of the project Einstein Telescope (ET), a design study of a third-generation gravitational wave observatory, will be reported.
319 citations
TL;DR: In this article, an updated search for gravitational waves from 116 known millisecond and young pulsars using data from the fifth science run of the LIGO detectors was presented, where ephemerides overlapping the run period were obtained using radio and X-ray observations.
Abstract: We present a search for gravitational waves from 116 known millisecond and young pulsars using data from the fifth science run of the LIGO detectors. For this search ephemerides overlapping the run period were obtained for all pulsars using radio and X-ray observations. We demonstrate an updated search method that allows for small uncertainties in the pulsar phase parameters to be included in the search. We report no signal detection from any of the targets and therefore interpret our results as upper limits on the gravitational wave signal strength. The most interesting limits are those for young pulsars. We present updated limits on gravitational radiation from the Crab pulsar, where the measured limit is now a factor of seven below the spin-down limit. This limits the power radiated via gravitational waves to be less than ~2% of the available spin-down power. For the X-ray pulsar J0537-6910 we reach the spin-down limit under the assumption that any gravitational wave signal from it stays phase locked to the X-ray pulses over timing glitches, and for pulsars J1913+1011 and J1952+3252 we are only a factor of a few above the spin-down limit. Of the recycled millisecond pulsars several of the measured upper limits are only about an order of magnitude above their spin-down limits. For these our best (lowest) upper limit on gravitational wave amplitude is 2.3x10^-26 for J1603-7202 and our best (lowest) limit on the inferred pulsar ellipticity is 7.0x10^-8 for J2124-3358.
187 citations
TL;DR: The first search for gravitational waves from compact binary coalescence using data from the Laser Interferometer Gravitational-Wave Observatory and Virgo detectors was reported in this article, which focused on signals from binary mergers with a total mass between 2 and 35M (circle dot).
Abstract: We report the results of the first search for gravitational waves from compact binary coalescence using data from the Laser Interferometer Gravitational-Wave Observatory and Virgo detectors. Five months of data were collected during the Laser Interferometer Gravitational-Wave Observatory's S5 and Virgo's VSR1 science runs. The search focused on signals from binary mergers with a total mass between 2 and 35M(circle dot). No gravitational waves are identified. The cumulative 90%-confidence upper limits on the rate of compact binary coalescence are calculated for nonspinning binary neutron stars, black hole-neutron star systems, and binary black holes to be 8: 7 X 10(-3) yr(-1) L-10(-1), 2.2 X 10(-3) yr(-1) L-10(-1), and 4.4 X 10(-4) yr(-1) L-10(-1), respectively, where L-10 is 10(10) times the blue solar luminosity. These upper limits are compared with astrophysical expectations.
132 citations
TL;DR: In this article, the authors search for known gravitational-wave signatures in temporal and directional coincidence with 22 short gamma-ray bursts (shortGRBs) that had sufficient gravitationalwave data available in multiple instruments during LIGO's fifth science run,============S5, and Virgo's first science run VSR1.
Abstract: Progenitor scenarios for short gamma-ray bursts (shortGRBs) include coalescenses of two neutron stars or a neutron
star and black hole, which would necessarily be accompanied by the emission of strong gravitational waves. We
present a search for these known gravitational-wave signatures in temporal and directional coincidence with 22
GRBs that had sufficient gravitational-wave data available in multiple instruments during LIGO’s fifth science run,
S5, and Virgo’s first science run, VSR1. We find no statistically significant gravitational-wave candidates within a
[−5, +1) s window around the trigger time of any GRB. Using the Wilcoxon–Mann–Whitney U-test, we find no
evidence for an excess of weak gravitational-wave signals in our sample of GRBs. We exclude neutron star–black
hole progenitors to a median 90% confidence exclusion distance of 6.7 Mpc.
119 citations
TL;DR: Virgo is one of the large, ground-based interferometers aimed at detecting gravitational waves as mentioned in this paper, but its sensitivity is limited by light in the output beams which is backscattered by seismically excited surfaces and couples back into the main beam of the interferometer.
Abstract: Virgo is one of the large, ground-based interferometers aimed at detecting gravitational waves. One of the technical problems limiting its sensitivity is caused by light in the output beams which is backscattered by seismically excited surfaces and couples back into the main beam of the interferometer. The resulting noise was thoroughly studied, measured and mitigated before Virgo's second science run (VSR2). The residual noise during VSR2, which increases in periods with a large microseism activity, is accurately predicted by the theoretical model. The scattered light has been associated with transient events in the gravitational-wave signal of the interferometer.
93 citations
TL;DR: In this article, a Superattenuator, a chain of mechanical filters designed to suppress seismic vibrations, starting from a few Hz, is measured by exciting its suspension point with sinuisodal forces and using the interferometer as sensor.
80 citations
TL;DR: In this article, the results of a search for gravitational-wave bursts associated with 137 gamma-ray bursts (GRBs) that were detected by satellite-based gamma ray experiments during the fifth LIGO science run and first Virgo science run were presented.
Abstract: We present the results of a search for gravitational-wave bursts associated with 137 gamma-ray bursts (GRBs) that were detected by satellite-based gamma-ray experiments during the fifth LIGO science run and first Virgo science run. The data used in this analysis were collected from 2005 November 4 to 2007 October 1, and most of the GRB triggers were from the Swift satellite. The search uses a coherent network analysis method that takes into account the different locations and orientations of the interferometers at the three LIGO-Virgo sites. We find no evidence for gravitational-wave burst signals associated with this sample of GRBs. Using simulated short-duration (<1 s) waveforms, we set upper limits on the amplitude of gravitational waves associated with each GRB. We also place lower bounds on the distance to each GRB under the assumption of a fixed energy emission in gravitational waves, with typical limits of D ~ 15 Mpc (E_GW^iso / 0.01 M_o c^2)^1/2 for emission at frequencies around 150 Hz, where the LIGO-Virgo detector network has best sensitivity. We present astrophysical interpretations and implications of these results, and prospects for corresponding searches during future LIGO-Virgo runs.
79 citations
TL;DR: In this article, the methods used to determine the parameters for sensitivity estimation and gravitational wave reconstruction are described and the main quantities to be calibrated are the frequency response of the mirror actuation and the sensing of the output power.
Abstract: The Virgo detector is a kilometer-length interferometer for gravitational wave detection located near Pisa (Italy). During its second science run (VSR2) in 2009, six months of data were accumulated with a sensitivity close to its design. In this paper, the methods used to determine the parameters for sensitivity estimation and gravitational wave reconstruction are described. The main quantities to be calibrated are the frequency response of the mirror actuation and the sensing of the output power. Focus is also put on their absolute timing. The monitoring of the calibration data as well as the parameter estimation with independent techniques are discussed to provide an estimation of the calibration uncertainties. Finally, the estimation of the Virgo sensitivity in the frequency-domain is described and typical sensitivities measured during VSR2 are shown.
TL;DR: In this paper, a search for known gravitational-wave signatures in temporal and directional coincidence with 22 short gamma-ray bursts (short GRBs) was carried out using the Wilcoxon-Mann-Whitney U test, finding no evidence for an excess of weak gravitational wave signals in their sample of GRBs.
Abstract: Progenitor scenarios for short gamma-ray bursts (short GRBs) include coalescenses of two neutron stars or a neutron star and black hole, which would necessarily be accompanied by the emission of strong gravitational waves. We present a search for these known gravitational-wave signatures in temporal and directional coincidence with 22 GRBs that had sufficient gravitational-wave data available in multiple instruments during LIGO's fifth science run, S5, and Virgo's first science run, VSR1. We find no statistically significant gravitational-wave candidates within a [-5, +1) s window around the trigger time of any GRB. Using the Wilcoxon-Mann-Whitney U test, we find no evidence for an excess of weak gravitational-wave signals in our sample of GRBs. We exclude neutron star-black hole progenitors to a median 90% CL exclusion distance of 6.7 Mpc.
01 Jan 2010
TL;DR: Virgo is designed to detect gravitational waves of both astrophysical and cosmological origin in the frequency range from a few Hz to a few kHz as discussed by the authors, and the second science run started at the beginning of July 2009 in coincidence with LIGO.
Abstract: Virgo is designed to detect gravitational waves of both astrophysical and cosmological origin in the frequency range from a few Hz to a few kHz. After the end of the first science run, partially overlapped with the LIGO fifth science run, the detector underwent several upgrades to improve its sensitivity. The second Virgo science run started at the beginning of July 2009 in coincidence with LIGO. A further upgrade is planned at beginning of 2010 with the installation of new suspensions for the test masses and of new mirrors. This will lead to a considerable improvement in the sensitivity and represents an intermediate step toward the development of the advanced detectors.
01 Jun 2010
TL;DR: In this paper, the authors summarize the sensitivity achieved by the LIGO and Virgo gravitational wave detectors for compact binary coalescence (CBC) searches during the fifth science run and the first science run.
Abstract: We summarize the sensitivity achieved by the LIGO and Virgo gravitational wave detectors for compact binary coalescence (CBC) searches during LIGO's fifth science run and Virgo's first science run. We present noise spectral density curves for each of the four detectors that operated during these science runs which are representative of the typical performance achieved by the detectors for CBC searches. These spectra are intended for release to the public as a summary of detector performance for CBC searches during these science runs.
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TL;DR: In this article, the authors summarize the sensitivity achieved by the LIGO and Virgo gravitational wave detectors for compact binary coalescence (CBC) searches during the fifth science run and the first science run.
Abstract: We summarize the sensitivity achieved by the LIGO and Virgo gravitational wave detectors for compact binary coalescence (CBC) searches during LIGO's fifth science run and Virgo's first science run. We present noise spectral density curves for each of the four detectors that operated during these science runs which are representative of the typical performance achieved by the detectors for CBC searches. These spectra are intended for release to the public as a summary of detector performance for CBC searches during these science runs.
01 May 2010
TL;DR: In this paper, a non-linear reconstruction of the differential arm length variations in free swinging Michelson configurations is used to calibrate the frequency dependent response of the Virgo mirror actuators and derive the detector in-loop response and sensitivity within 5%.
Abstract: Virgo is a kilometer-length interferometer for gravitationnal waves detection located near Pisa. Its first science run, VSR1, occured from May to October 2007. The aims of the calibration are to measure the detector sensitivity and to reconstruct the time series of the gravitationnal wave strain h(t). The absolute length calibration is based on an original non-linear reconstruction of the differential arm length variations in free swinging Michelson configurations. It uses the laser wavelength as length standard. This method is used to calibrate the frequency dependent response of the Virgo mirror actuators and derive the detector in-loop response and sensitivity within ~ 5%. The principle of the strain reconstruction is highlighted and the h(t) systematic errors are estimated. A photon calibrator is used to check the sign of h(t). The reconstructed h(t) during VSR1 is valid from 10 Hz up to 10 kHz with systematic errors estimated to 6% in amplitude. The phase error is estimated to be 70 mrad below 1.9 kHz and 6 μs above.
TL;DR: In this article, the performance of the longitudinal sensing and control system of the Virgo gravitational wave detector is described, which is able to stably maintain the RMS residual fluctuation of the interferometer longitudinal degrees of freedom around or below 10-11m.
TL;DR: A remotely controlled system using a motorized lambda=2 waveplate inserted between the first polarizer and the Faraday rotator has proven its capability to restore the optical isolation to a value close to the one set up in air.
Abstract: In-vacuum Faraday isolators (FIs) are used in gravitational wave interferometers to prevent the disturbance caused by light reflected back to the input port from the interferometer itself The efficiency of the optical isolation is becoming more critical with the increase of laser input power An in-vacuum FI, used in a gravitational wave experiment (Virgo), has a 20mm clear aperture and is illuminated by an almost 20W incoming beam, having a diameter of about 5mm When going in vacuum at 10−6mbar, a degradation of the isolation exceeding 10dB was observed A remotely controlled system using a motorized λ/2 waveplate inserted between the first polarizer and the Faraday rotator has proven its capability to restore the optical isolation to a value close to the one set up in air
TL;DR: In this article, a non-linear reconstruction of the differential arm length variations in free swinging Michelson configurations is used to calibrate the frequency dependent response of the Virgo mirror actuators and derive the detector in-loop response and sensitivity within 5%.
Abstract: Virgo is a kilometer-length interferometer for gravitational waves detection located near Pisa. Its first science run, VSR1, occured from May to October 2007. The aims of the calibration are to measure the detector sensitivity and to reconstruct the time series of the gravitational wave strain h(t). The absolute length calibration is based on an original non-linear reconstruction of the differential arm length variations in free swinging Michelson configurations. It uses the laser wavelength as length standard. This method is used to calibrate the frequency dependent response of the Virgo mirror actuators and derive the detector in-loop response and sensitivity within ~5%. The principle of the strain reconstruction is highlighted and the h(t) systematic errors are estimated. A photon calibrator is used to check the sign of h(t). The reconstructed h(t) during VSR1 is valid from 10 Hz up to 10 kHz with systematic errors estimated to 6% in amplitude. The phase error is estimated to be 70 mrad below 1.9 kHz and 6 micro-seconds above.
01 Aug 2010
TL;DR: In this article, several software tools were used to perform on-line and of-line noise analysis as a support to commissioning activities, to monitor the rate of glitches, the occurrence of non stationary noise, the presence of environmental contamination, the behavior of narrow spectral features and the coherence with auxiliary channels.
Abstract: Several software tools were used to perform on-line and of-line noise analysis as a support to commissioning activities, to monitor the rate of glitches, the occurrence of non stationary noise, the presence of environmental contamination, the behavior of narrow spectral features and the coherence with auxiliary channels. We report about the use of these tools to study the main sources of identified noise: broadband, spectral lines and glitches. Plans for the upgrade of the tools will be presented, for example for lines identification purpose to let the scientists in control room do noise characterization in an easier way.