Showing papers by "Matthew Pitkin published in 2011"
TL;DR: In this paper, the authors demonstrate the squeezed-light enhancement of GEO600, which will be the GW observatory operated by the LIGO Scientific Collaboration in its search for GWs for the next 3-4 years.
Abstract: Around the globe several observatories are seeking the first direct detection of gravitational waves (GWs). These waves are predicted by Einstein’s general theory of relativity1 and are generated, for example, by black-hole binary systems2. Present GW detectors are Michelson-type kilometre-scale laser interferometers measuring the distance changes between mirrors suspended in vacuum. The sensitivity of these detectors at frequencies above several hundred hertz is limited by the vacuum (zero-point) fluctuations of the electromagnetic field. A quantum technology—the injection of squeezed light3—offers a solution to this problem. Here we demonstrate the squeezed-light enhancement of GEO 600, which will be the GW observatory operated by the LIGO Scientific Collaboration in its search for GWs for the next 3–4 years. GEO 600 now operates with its best ever sensitivity, which proves the usefulness of quantum entanglement and the qualification of squeezed light as a key technology for future GW astronomy4.
810 citations
20 May 2011
TL;DR: In this article, the conceptual design of a third generation gravitational wave observatory named the Einstein Telescope (ET) has been described with the support of the European Community's Seventh Framework Programme (FP7/2007-2013) under grant agreement n 211743.
Abstract: This document describes the Conceptual Design of a third generation gravitational wave observatory named Einstein Telescope (“ET”). The design of this new research infrastructure has been realised with the support of the European Community’s Seventh Framework Programme (FP7/2007-2013) under grant agreement n 211743. In this document are described the fundamental design options, the site requirements, the main technological solutions, a rough evaluation of the costs and a schematic time plan.
192 citations
TL;DR: In this paper, the authors present direct upper limits on gravitational wave emission from the Crab pulsar using data from the first 9 months of the fifth science run of the LIGO.
Abstract: We present direct upper limits on gravitational wave emission from the Crab pulsar using data from the first 9 months of the fifth science run of the Laser Interferometer Gravitational-wave Observatory (LIGO). These limits are based on two searches. In the first we assume that the gravitational wave emission follows the observed radio timing, giving an upper limit on gravitational wave emission that beats indirect limits inferred from the spin-down and braking index of the pulsar and the energetics of the nebula. In the second we allow for a small mismatch between the gravitational and radio signal frequencies and interpret our results in the context of two possible gravitational wave emission mechanisms.
160 citations
01 Jun 2011
105 citations
TL;DR: In this paper, a low-latency analysis pipeline was used to identify and localize GW event candidates and to request images of targeted sky locations, where a catalog of nearby galaxies and Milky Way globular clusters were used to select the most promising sky positions to be imaged.
Abstract: Aims. A transient astrophysical event observed in both gravitational wave (GW) and electromagnetic (EM) channels would yield rich scientific rewards. A first program initiating EM follow-ups to possible transient GW events has been developed and exercised by the LIGO and Virgo community in association with several partners. In this paper, we describe and evaluate the methods used to promptly identify and localize GW event candidates and to request images of targeted sky locations.
Methods. During two observing periods (Dec 17 2009 to Jan 8 2010 and Sep 2 to Oct 20 2010), a low-latency analysis pipeline was used to identify GW event candidates and to reconstruct maps of possible sky locations. A catalog of nearby galaxies and Milky Way globular clusters was used to select the most promising sky positions to be imaged, and this directional information was delivered to EM observatories with time lags of about thirty minutes. A Monte Carlo simulation has been used to evaluate the low-latency GW pipeline's ability to reconstruct source positions correctly.
Results. For signals near the detection threshold, our low-latency algorithms often localized simulated GW burst signals to tens of square degrees, while neutron star/neutron star inspirals and neutron star/black hole inspirals were localized to a few hundred square degrees. Localization precision improves for moderately stronger signals. The correct sky location of signals well above threshold and originating from nearby galaxies may be observed with ~50% or better probability with a few pointings of wide-field telescopes.
104 citations
TL;DR: Two directional searches for persistent GWs using data from the LIGO S5 science run are performed: one optimized for pointlike sources and one for arbitrary extended sources, finding no evidence to support the detection of GWs.
Abstract: The gravitational-wave (GW) sky may include nearby pointlike sources as well as stochastic backgrounds. We perform two directional searches for persistent GWs using data from the LIGO S5 science run: one optimized for pointlike sources and one for arbitrary extended sources. Finding no evidence to support the detection of GWs, we present 90% confidence level (C.L.) upper-limit maps of GW strain power with typical values between 2-20×10-50strain2Hz-1 and 5-35×10-49strain2Hz-1sr-1 for pointlike and extended sources, respectively. The latter result is the first of its kind. We also set 90% C.L. limits on the narrow-band root-mean-square GW strain from interesting targets including Sco X-1, SN 1987A and the Galactic center as low as ≈7×10-25 in the most sensitive frequency range near 160 Hz.
97 citations
TL;DR: The winners and runners-up in this competition will be announced at a later date, but it is likely that some of the winners will have already been announced in the competition.
Abstract: We present the first modeled search for gravitational waves using the complete binary black hole gravitational waveform from inspiral through the merger and ringdown for binaries with negligible component spin. We searched approximately 2 years of LIGO data taken between November 2005 and September 2007 for systems with component masses of 1-99 solar masses and total masses of 25-100 solar masses. We did not detect any plausible gravitational-wave signals but we do place upper limits on the merger rate of binary black holes as a function of the component masses in this range. We constrain the rate of mergers for binary black hole systems with component masses between 19 and 28 solar masses and negligible spin to be no more than 2.0 per Mpc^3 per Myr at 90% confidence.
83 citations
TL;DR: In this paper, the results of a search for GW bursts from six galactic magnetars that is sensitive to neutron star f-modes, thought to be the most efficient GW emitting oscillatory modes in compact stars, were presented.
Abstract: Soft gamma repeaters (SGRs) and anomalous X-ray pulsars (AXPs) are thought to be magnetars: neutron stars powered by extreme magnetic fields. These rare objects are characterized by repeated and sometimes spectacular gamma-ray bursts. The burst mechanism might involve crustal fractures and excitation of non-radial modes which would emit gravitational waves (GWs). We present the results of a search for GW bursts from six galactic magnetars that is sensitive to neutron star f-modes, thought to be the most efficient GW emitting oscillatory modes in compact stars. One of them, SGR 0501+4516, is likely ~1 kpc from Earth, an order of magnitude closer than magnetars targeted in previous GW searches. A second, AXP 1E 1547.0-5408, gave a burst with an estimated isotropic energy >1044 erg which is comparable to the giant flares. We find no evidence of GWs associated with a sample of 1279 electromagnetic triggers from six magnetars occurring between 2006 November and 2009 June, in GW data from the LIGO, Virgo, and GEO600 detectors. Our lowest model-dependent GW emission energy upper limits for band- and time-limited white noise bursts in the detector sensitive band, and for f-mode ringdowns (at 1090 Hz), are 3.0 × 1044 d 2 1 erg and 1.4 × 1047 d 2 1 erg, respectively, where $d_\mathrm{1} = \frac{d_{\mathrm{0501}}}{1\,\mathrm{kpc}}$ and d 0501 is the distance to SGR 0501+4516. These limits on GW emission from f-modes are an order of magnitude lower than any previous, and approach the range of electromagnetic energies seen in SGR giant flares for the first time.
80 citations
TL;DR: In this article, direct upper limits on continuous gravitational wave emission from the Vela pulsar using data from the Virgo detector's second science run were obtained using three independent methods.
Abstract: We present direct upper limits on continuous gravitational wave emission from the Vela pulsar using data from the Virgo detector's second science run. These upper limits have been obtained using three independent methods that assume the gravitational wave emission follows the radio timing. Two of the methods produce frequentist upper limits for an assumed known orientation of the star's spin axis and value of the wave polarization angle of, respectively, $1.9\ee{-24}$ and $2.2\ee{-24}$, with 95% confidence. The third method, under the same hypothesis, produces a Bayesian upper limit of $2.1\ee{-24}$, with 95% degree of belief. These limits are below the indirect {\it spin-down limit} of $3.3\ee{-24}$ for the Vela pulsar, defined by the energy loss rate inferred from observed decrease in Vela's spin frequency, and correspond to a limit on the star ellipticity of $\sim 10^{-3}$. Slightly less stringent results, but still well below the spin-down limit, are obtained assuming the star's spin axis inclination and the wave polarization angles are unknown.
78 citations
TL;DR: In this paper, the authors present the first direct search for the gravitational-wave emission associated with oscillations of the fundamental quadrupole mode excited by a pulsar timing glitch.
Abstract: The physical mechanisms responsible for pulsar timing glitches are thought to excite quasinormal mode oscillations in their parent neutron star that couple to gravitational-wave emission. In August 2006, a timing glitch was observed in the radio emission of PSR B0833-45, the Vela pulsar. At the time of the glitch, the two colocated Hanford gravitational-wave detectors of the Laser Interferometer Gravitational wave observatory (LIGO) were operational and taking data as part of the fifth LIGO science run (S5). We present the first direct search for the gravitational-wave emission associated with oscillations of the fundamental quadrupole mode excited by a pulsar timing glitch. No gravitational-wave detection
candidate was found. We place Bayesian 90% confidence upper limits of 6.3 x 10^(-21) to 1.4 x 10^(-20) on the peak intrinsic strain amplitude of gravitational-wave ring-down signals, depending on which spherical harmonic mode is excited. The corresponding range of energy upper limits is 5.0 x 10^(-44) to 1.3 x 10^(-45) erg.
65 citations
TL;DR: In this paper, the authors present a survey of the state-of-the-art work in this area, including the following: A.A. Adhikari, P.B. Abadie, B.Babak, A.C. Anderson, W.M. Brandes, M.Barriga, E.C., A.B., C.C, C.Chaibi, O.Chakrabarty, O'Brien, O.'Brien, S.Capellaro, O 'Brien, T.
Abstract: J. Abadie, B. P. Abbott, R. Abbott, M. Abernathy, T. Accadia, F. Acernese, C. Adams, R. Adhikari, P. Ajith, B. Allen, G. S. Allen, E. Amador Ceron, R. S. Amin, S. B. Anderson, W.G. Anderson, F. Antonucci, M.A. Arain, M. C. Araya, M. Aronsson, Y. Aso, S.M. Aston, P. Astone, D. Atkinson, P. Aufmuth, C. Aulbert, S. Babak, P. Baker, G. Ballardin, T. Ballinger, S. Ballmer, D. Barker, S. Barnum, F. Barone, B. Barr, P. Barriga, L. Barsotti, M. Barsuglia, M.A. Barton, I. Bartos, R. Bassiri, M. Bastarrika, J. Bauchrowitz, Th. S. Bauer, B. Behnke, M.G. Beker, A. Belletoile, M. Benacquista, A. Bertolini, J. Betzwieser, N. Beveridge, P. T. Beyersdorf, I. A. Bilenko, G. Billingsley, J. Birch, S. Birindelli, R. Biswas, M. Bitossi, M.A. Bizouard, E. Black, J. K. Blackburn, L. Blackburn, D. Blair, B. Bland, M. Blom, C. Boccara, O. Bock, T. P. Bodiya, R. Bondarescu, F. Bondu, L. Bonelli, R. Bonnand, R. Bork, M. Born, V. Boschi, S. Bose, L. Bosi, B. Bouhou, M. Boyle, S. Braccini, C. Bradaschia, P. R. Brady, V. B. Braginsky, J. E. Brau, J. Breyer, D.O. Bridges, A. Brillet, M. Brinkmann, V. Brisson, M. Britzger, A. F. Brooks, D. A. Brown, R. Budzynski, T. Bulik, H. J. Bulten, A. Buonanno, J. Burguet–Castell, O. Burmeister, D. Buskulic, C. Buy, R. L. Byer, L. Cadonati, G. Cagnoli, J. Cain, E. Calloni, J. B. Camp, E. Campagna, P. Campsie, J. Cannizzo, K. Cannon, B. Canuel, J. Cao, C. Capano, F. Carbognani, S. Caride, S. Caudill, M. Cavaglia, F. Cavalier, R. Cavalieri, G. Cella, C. Cepeda, E. Cesarini, O. Chaibi, T. Chalermsongsak, E. Chalkley, P. Charlton, E. Chassande-Mottin, S. Chelkowski, Y. Chen, A. Chincarini, N. Christensen, S. S. Y. Chua, C. T.Y. Chung, D. Clark, J. Clark, J. H. Clayton, F. Cleva, E. Coccia, C. N. Colacino, J. Colas, A. Colla, M. Colombini, R. Conte, D. Cook, T. R. Corbitt, N. Cornish, A. Corsi, C. A. Costa, J.-P. Coulon, D.M. Coward, D. C. Coyne, J. D. E. Creighton, T.D. Creighton, A.M. Cruise, R.M. Culter, A. Cumming, L. Cunningham, E. Cuoco, K. Dahl, S. L. Danilishin, R. Dannenberg, S. D’Antonio, K. Danzmann, K. Das, V. Dattilo, B. Daudert, M. Davier, G. Davies, A. Davis, E. J. Daw, R. Day, T. Dayanga, R. De Rosa, D. DeBra, G. Debreczeni, J. Degallaix, M. del Prete, V. Dergachev, R. DeRosa, R. DeSalvo, P. Devanka, S. Dhurandhar, L. Di Fiore, A. Di Lieto, I. Di Palma, M. Di Paolo Emilio, A. Di Virgilio, M. Diaz, A. Dietz, F. Donovan, K. L. Dooley, E. E. Doomes, S. Dorsher, E. S. D. Douglas, M. Drago, R.W. P. Drever, J. C. Driggers, J. Dueck, J.-C. Dumas, S. Dwyer, T. Eberle, M. Edgar, M. Edwards, A. Effler, P. Ehrens, G. Ely, R. Engel, T. Etzel, M. Evans, T. Evans, V. Fafone, S. Fairhurst, Y. Fan, B. F. Farr, D. Fazi, H. Fehrmann, D. Feldbaum, I. Ferrante, F. Fidecaro, L. S. Finn, I. Fiori, R. Flaminio, M. Flanigan, K. Flasch, S. Foley, C. Forrest, E. Forsi, L. A. Forte, N. Fotopoulos, J.-D. Fournier, J. Franc, S. Frasca, F. Frasconi, M. Frede, M. Frei, Z. Frei, A. Freise, R. Frey, T. T. Fricke, D. Friedrich, P. Fritschel, V. V. Frolov, P. Fulda, M. Fyffe, M. Galimberti, L. Gammaitoni, J. A. Garofoli, F. Garufi, M. E. Gaspar, G. Gemme, E. Genin, A. Gennai, I. Gholami, S. Ghosh, J. A. Giaime, S. Giampanis, K. D. Giardina, A. Giazotto, C. Gill, E. Goetz, L.M. Goggin, G. Gonzalez, M. L. Gorodetsky, S. Gosler, R. Gouaty, C. Graef, M. Granata, A. Grant, S. Gras, C. Gray, R. J. S. Greenhalgh, A.M. Gretarsson, C. Greverie, R. Grosso, H. Grote, S. Grunewald, G.M. Guidi, E. K. Gustafson, R. Gustafson, B. Hage, P. Hall, J.M. Hallam, D. Hammer, G. Hammond, J. Hanks, C. Hanna, J. Hanson, J. Harms, G.M. Harry, I.W. Harry, E. D. Harstad, K. Haughian, K. Hayama, J.-F. Hayau, T. Hayler, J. Heefner, H. Heitmann, P. Hello, I. S. Heng, A.W. Heptonstall, M. Hewitson, S. Hild, E. Hirose, D. Hoak, K. A. Hodge, K. Holt, D. J. Hosken, J. Hough, E. J. Howell, D. Hoyland, D. Huet, B. Hughey, S. Husa, S. H. Huttner, T. Huynh–Dinh, D. R. Ingram, R. Inta, T. Isogai, A. Ivanov, P. Jaranowski, W.W. Johnson, D. I. Jones, G. Jones, R. Jones, L. Ju, P. Kalmus, V. Kalogera, S. Kandhasamy, J. B. Kanner, E. Katsavounidis, K. Kawabe, S. Kawamura, F. Kawazoe, W. Kells, D.G. Keppel, A. Khalaidovski, F. Y. Khalili, E. A. Khazanov, H. Kim, P. J. King, D. L. Kinzel, J. S. Kissel, S. Klimenko, V. Kondrashov, R. Kopparapu, S. Koranda, I. Kowalska, D. Kozak, T. Krause, V. Kringel, S. Krishnamurthy, B. Krishnan, A. Krolak, G. Kuehn, J. Kullman, R. Kumar, P. Kwee, M. Landry, M. Lang, B. Lantz, N. Lastzka, A. Lazzarini, P. Leaci, J. Leong, I. Leonor, N. Leroy, N. Letendre, J. Li, T. G. F. Li, N. Liguori, H. Lin, P. E. Lindquist, N. A. Lockerbie, D. Lodhia, M. Lorenzini, V. Loriette, M. Lormand, G. Losurdo, P. Lu, J. Luan, M. Lubinski, A. Lucianetti, H. Luck, A.D. Lundgren, B. Machenschalk, M. MacInnis, M. Mageswaran, K. Mailand, E. Majorana, C. Mak, I. Maksimovic, N. Man, I. Mandel, V. Mandic, M. Mantovani, F. Marchesoni, F. Marion, S. Marka, Z. Marka, E. Maros, J. Marque, F. Martelli, I.W. Martin, R.M. Martin, J. N. Marx, K. Mason, A. Masserot, F. Matichard, L. Matone, R. A. Matzner, N. Mavalvala, R. McCarthy, D. E. McClelland, S. C. McGuire, G. McIntyre, G. McIvor, D. J. A. McKechan, G. Meadors, M. Mehmet, T. Meier, A. Melatos, A. C. Melissinos, G. Mendell, D. F. Menendez, R. A. Mercer, L. Merill, S. Meshkov, C. Messenger, M. S. Meyer, H. Miao, C. Michel, L. Milano, J. Miller, Y. Minenkov, Y. Mino, S. Mitra, V. P. Mitrofanov, G. Mitselmakher, R. Mittleman, B. Moe, M. Mohan, S. D. Mohanty, S. R. P. Mohapatra, D. Moraru, PHYSICAL REVIEW D 85, 089904(E) (2012)
TL;DR: In this paper, the intrinsic ability to detect, and estimate the gravitational wave amplitude for non-accreting pulsars was studied using spin-down limits on emission as a guide, assuming that they are triaxial stars emitting at precisely twice the known rotation frequency.
Abstract: Several searches for gravitational waves from a selection of known pulsars have been performed with data from the science runs of the LIGO gravitational wave detectors. So far these have lead to no detection, but upper limits on the gravitational wave amplitudes have been set. Here we study our intrinsic ability to detect, and estimate the gravitational wave amplitude for non-accreting pulsars. Using spin-down limits on emission as a guide we examine amplitudes that would be required to observe known pulsars with future detectors (Advanced LIGO, Advanced Virgo and the Einstein Telescope), assuming that they are triaxial stars emitting at precisely twice the known rotation frequency. Maximum allowed amplitudes depend on the stars’ equation of state (e.g. a normal neutron star, a quark star, a hybrid star) and the theoretical mass quadrupoles that they can sustain. We study what range of quadrupoles, and therefore EoS, would be consistent with being able to detect these sources. For globular cluster pulsars, with spin-downs masked by accelerations within the cluster, we examine what spin-down values gravitational wave observations would be able to set. For all pulsars we also alternatively examine what internal magnetic fields they would need to sustain observable ellipticities.
TL;DR: A review of the current generation of ground-based detectors is presented in this paper, in addition to the astrophysical results gained thus far, and the concept and design of possible future "third generation" gravitational wave detectors, such as the Einstein Telescope (ET), is discussed.
Abstract: Significant progress has been made in recent years on the development of gravitational wave detectors. Sources such as coalescing compact binary systems, neutron stars in low-mass X-ray binaries, stellar collapses and pulsars are all possible candidates for detection. The most promising design of gravitational wave detector uses test masses a long distance apart and freely suspended as pendulums on Earth or in drag-free craft in space. The main theme of this review is a discussion of the mechanical and optical principles used in the various long baseline systems in operation around the world - LIGO (USA), Virgo (Italy/France), TAMA300 and LCGT (Japan), and GEO600 (Germany/U.K.) - and in LISA, a proposed space-borne interferometer. A review of recent science runs from the current generation of ground-based detectors will be discussed, in addition to highlighting the astrophysical results gained thus far. Looking to the future, the major upgrades to LIGO (Advanced LIGO), Virgo (Advanced Virgo), LCGT and GEO600 (GEO-HF) will be completed over the coming years, which will create a network of detectors with significantly improved sensitivity required to detect gravitational waves. Beyond this, the concept and design of possible future "third generation" gravitational wave detectors, such as the Einstein Telescope (ET), will be discussed.
01 Mar 2011
TL;DR: A.J. Abadie, B. Abbott, R. Adhikari, P. Allen, E. Barriga, L. Barsotti, M. Bock, T. Blair, D. Donovan, K. Frei, A. Freisinger, C. Freise, S. Fricke, J. Friedrich, P Fritschel, V. Fairhurst, Y.
Journal Article•
TL;DR: In this article, the authors present a survey of the state-of-the-art work in this area: A.A. Adhikari, P. A. Ajith, B. Barriga, S.A., A.B. Bennett, J.C. Dooley, E.M. Brandt, J-C. Hohenberger, M.E.Charlton, N.C., C.Chua, C.C, T.Chung, D.Chakrabarty, D-C., D.
Abstract: J. Abadie, B. P. Abbott, R. Abbott, R. Adhikari, P. Ajith, B. Allen, G. Allen, E. Amador Ceron, R. S. Amin, S. B. Anderson, W.G. Anderson, M.A. Arain, M. Araya, Y. Aso, S. Aston, P. Aufmuth, C. Aulbert, S. Babak, P. Baker, S. Ballmer, D. Barker, B. Barr, P. Barriga, L. Barsotti, M.A. Barton, I. Bartos, R. Bassiri, M. Bastarrika, B. Behnke, M. Benacquista, M. F. Bennett, J. Betzwieser, P. T. Beyersdorf, I. A. Bilenko, G. Billingsley, R. Biswas, E. Black, J. K. Blackburn, L. Blackburn, D. Blair, B. Bland, O. Bock, T. P. Bodiya, R. Bondarescu, R. Bork, M. Born, S. Bose, P. R. Brady, V. B. Braginsky, J. E. Brau, J. Breyer, D.O. Bridges, M. Brinkmann, M. Britzger, A. F. Brooks, D.A. Brown, A. Bullington, A. Buonanno, O. Burmeister, R. L. Byer, L. Cadonati, J. Cain, J. B. Camp, J. Cannizzo, K. C. Cannon, J. Cao, C. Capano, L. Cardenas, S. Caudill, M. Cavaglià, C. Cepeda, T. Chalermsongsak, E. Chalkley, P. Charlton, S. Chatterji, S. Chelkowski, Y. Chen, N. Christensen, S. S. Y. Chua, C. T. Y. Chung, D. Clark, J. Clark, J. H. Clayton, R. Conte, D. Cook, T. R. C. Corbitt, N. Cornish, D. Coward, D. C. Coyne, J. D. E. Creighton, T. D. Creighton, A.M. Cruise, R.M. Culter, A. Cumming, L. Cunningham, K. Dahl, S. L. Danilishin, K. Danzmann, B. Daudert, G. Davies, E. J. Daw, T. Dayanga, D. DeBra, J. Degallaix, V. Dergachev, R. DeSalvo, S. Dhurandhar, M. Dı́az, F. Donovan, K. L. Dooley, E. E. Doomes, R.W. P. Drever, J. Driggers, J. Dueck, I. Duke, J.-C. Dumas, S. Dwyer, M. Edgar, M. Edwards, A. Effler, P. Ehrens, T. Etzel, M. Evans, T. Evans, S. Fairhurst, Y. Faltas, Y. Fan, D. Fazi, H. Fehrmann, L. S. Finn, K. Flasch, S. Foley, C. Forrest, N. Fotopoulos, M. Frede, M. Frei, Z. Frei, A. Freise, R. Frey, T. T. Fricke, D. Friedrich, P. Fritschel, V. V. Frolov, P. Fulda, M. Fyffe, J. A. Garofoli, S. Ghosh, J. A. Giaime, S. Giampanis, K.D. Giardina, E. Goetz, L.M. Goggin, G. González, S. Goßler, A. Grant, S. Gras, C. Gray, R. J. S. Greenhalgh, A.M. Gretarsson, R. Grosso, H. Grote, S. Grunewald, E. K. Gustafson, R. Gustafson, B. Hage, J.M. Hallam, D. Hammer, G. D. Hammond, C. Hanna, J. Hanson, J. Harms, G.M. Harry, I.W. Harry, E. D. Harstad, K. Haughian, K. Hayama, T. Hayler, J. Heefner, I. S. Heng, A. Heptonstall, M. Hewitson, S. Hild, E. Hirose, D. Hoak, K. A. Hodge, K. Holt, D. J. Hosken, J. Hough, E. Howell, D. Hoyland, B. Hughey, S. Husa, S. H. Huttner, D. R. Ingram, T. Isogai, A. Ivanov, W.W. Johnson, D. I. Jones, G. Jones, R. Jones, L. Ju, P. Kalmus, V. Kalogera, S. Kandhasamy, J. Kanner, E. Katsavounidis, K. Kawabe, S. Kawamura, F. Kawazoe, W. Kells, D. G. Keppel, A. Khalaidovski, F. Y. Khalili, R. Khan, E. Khazanov, H. Kim, P. J. King, J. S. Kissel, S. Klimenko, K. Kokeyama, V. Kondrashov, R. Kopparapu, S. Koranda, D. Kozak, V. Kringel, B. Krishnan, G. Kuehn, J. Kullman, R. Kumar, P. Kwee, P. K. Lam, M. Landry, M. Lang, B. Lantz, N. Lastzka, A. Lazzarini, P. Leaci, M. Lei, N. Leindecker, I. Leonor, H. Lin, P. E. Lindquist, T. B. Littenberg, N.A. Lockerbie, D. Lodhia, M. Lormand, P. Lu, M. Lubinski, A. Lucianetti, H. Lück, A. Lundgren, B. Machenschalk, M. MacInnis, M. Mageswaran, K. Mailand, C. Mak, I. Mandel, V. Mandic, S. Márka, Z. Márka, A. Markosyan, J. Markowitz, E. Maros, I.W. Martin, R.M. Martin, J. N. Marx, K. Mason, F. Matichard, L. Matone, R. A. Matzner, N. Mavalvala, R. McCarthy, D. E. McClelland, S. C. McGuire, G. McIntyre, D. J. A. McKechan, M. Mehmet, A. Melatos, A. C. Melissinos, G. Mendell, D. F. Menéndez, R. A. Mercer, L. Merrill, S. Meshkov, C. Messenger, M. S. Meyer, H. Miao, J. Miller, Y. Mino, S. Mitra, V. P. Mitrofanov, G. Mitselmakher, R. Mittleman, O. Miyakawa, B. Moe, S. D. Mohanty, S. R. P. Mohapatra, G. Moreno, K. Mors, K. Mossavi, C. MowLowry, G. Mueller, H. Müller-Ebhardt, S. Mukherjee, A. Mullavey, J. Munch, P. G. Murray, T. Nash, R. Nawrodt, J. Nelson, G. Newton, E. Nishida, A. Nishizawa, J. O’Dell, B. O’Reilly, R. O’Shaughnessy, E. Ochsner, G.H. Ogin, R. Oldenburg, D. J. Ottaway, R. S. Ottens, H. Overmier, B. J. Owen, A. Page, Y. Pan, C. Pankow, M.A. Papa, P. Patel, D. Pathak, M. Pedraza, L. Pekowsky, S. Penn, C. Peralta, A. Perreca, M. Pickenpack, I.M. Pinto, M. Pitkin, H. J. Pletsch, M.V. Plissi, F. Postiglione, M. Principe, R. Prix, L. Prokhorov, O. Puncken, V. Quetschke, F. J. Raab, D. S. Rabeling, H. Radkins, P. Raffai, Z. Raics, M. Rakhmanov, V. Raymond, C.M. Reed, T. Reed, H. Rehbein, S. Reid, D.H. Reitze, R. Riesen, K. Riles, P. Roberts, N.A. Robertson, C. Robinson, E. L. Robinson, S. Roddy, C. Röver, J. Rollins, J. D. Romano, J. H. Romie, S. Rowan, A. Rüdiger, K. Ryan, S. Sakata, L. Sammut, L. Sancho de la Jordana, V. Sandberg, V. Sannibale, L. Santamarı́a, G. Santostasi, S. Saraf, P. Sarin, B. S. Sathyaprakash, S. Sato, M. Satterthwaite, P. R. Saulson, R. Savage, R. Schilling, R. Schnabel, R. Schofield, B. Schulz, B. F. Schutz, P. Schwinberg, J. Scott, S.M. Scott, A. C. Searle, F. Seifert, D. Sellers, A. S. Sengupta, A. Sergeev, B. Shapiro, PHYSICAL REVIEW D 83, 042001 (2011)
Posted Content•
TL;DR: In this paper, the authors presented 90% confidence level (CL) upper-limit maps of GW strain power with typical values between 2-20x10^-50 strain and 5-35x10−49 strain for pointlike and extended sources respectively.
Abstract: The gravitational-wave (GW) sky may include nearby pointlike sources as well as astrophysical and cosmological stochastic backgrounds. Since the relative strength and angular distribution of the many possible sources of GWs are not well constrained, searches for GW signals must be performed in a model-independent way. To that end we perform two directional searches for persistent GWs using data from the LIGO S5 science run: one optimized for pointlike sources and one for arbitrary extended sources. The latter result is the first of its kind. Finding no evidence to support the detection of GWs, we present 90% confidence level (CL) upper-limit maps of GW strain power with typical values between 2-20x10^-50 strain^2 Hz^-1 and 5-35x10^-49 strain^2 Hz^-1 sr^-1 for pointlike and extended sources respectively. The limits on pointlike sources constitute a factor of 30 improvement over the previous best limits. We also set 90% CL limits on the narrow-band root-mean-square GW strain from interesting targets including Sco X-1, SN1987A and the Galactic Center as low as ~7x10^-25 in the most sensitive frequency range near 160 Hz. These limits are the most constraining to date and constitute a factor of 5 improvement over the previous best limits.
TL;DR: In this paper, the intrinsic ability to detect, and estimate the gravitational wave amplitude for non-accreting pulsars, using spin-down limits on emission as a guide, was examined.
Abstract: Several past searches for gravitational waves from a selection of known pulsars have been performed with data from the science runs of the Laser Inferometer Gravitational-wave Observatory (LIGO) gravitational wave detectors. So far these have lead to no detection, but upper limits on the gravitational wave amplitudes have been set. Here we study our intrinsic ability to detect, and estimate the gravitational wave amplitude for non-accreting pulsars. Using spin-down limits on emission as a guide we examine amplitudes that would be required to observe known pulsars with future detectors (Advanced LIGO, Advanced Virgo and the Einstein Telescope), assuming that they are triaxial stars emitting at precisely twice the known rotation frequency. Maximum allowed amplitudes depend on the stars' equation of state (e.g. a normal neutron star, a quark star, a hybrid star) and the theoretical mass quadrupoles that they can sustain. We study what range of quadrupoles, and therefore equations of state, would be consistent with being able to detect these sources. For globular cluster pulsars, with spin-downs masked by accelerations within the cluster, we examine what spin-down values gravitational wave observations would be able to set. For all pulsars we also alternatively examine what internal magnetic fields they would need to sustain observable ellipticities.