Showing papers by "H. Overmier published in 2004"

Detector description and performance for the first coincidence observations between LIGO and GEO

Abstract: For 17 days in August and September 2002, the LIGO and GEO interferometer gravitational wave detectors were operated in coincidence to produce their first data for scientific analysis. Although the detectors were still far from their design sensitivity levels, the data can be used to place better upper limits on the flux of gravitational waves incident on the earth than previous direct measurements. This paper describes the instruments and the data in some detail, as a companion to analysis papers based on the first data.

Setting upper limits on the strength of periodic gravitational waves from PSR J1939+2134 using the first science data from the GEO 600 and LIGO detectors

Abstract: Data collected by the GEO 600 and LIGO interferometric gravitational wave detectors during their first observational science run were searched for continuous gravitational waves from the pulsar J1939+2134 at twice its rotation frequency. Two independent analysis methods were used and are demonstrated in this paper: a frequency domain method and a time domain method. Both achieve consistent null results, placing new upper limits on the strength of the pulsar’s gravitational wave emission. A model emission mechanism is used to interpret the limits as a constraint on the pulsar’s equatorial ellipticity.

First upper limits from LIGO on gravitational wave bursts

Abstract: We report on a search for gravitational wave bursts using data from the first science run of the Laser Interferometer Gravitational Wave Observatory (LIGO) detectors. Our search focuses on bursts with durations ranging from 4 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 a 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 hrss; typical sensitivities lie in the range hrss∼10-19–10-17strain/√Hz, depending on the waveform. We discuss improvements in the search method that will be applied to future science data from LIGO and other gravitational wave detectors.

Analysis of first LIGO science data for stochastic gravitational waves

Abstract: We present the analysis of between 50 and 100 h of coincident interferometric strain data used to search for and establish an upper limit on a stochastic background of gravitational radiation. These data come from the first LIGO science run, during which all three LIGO interferometers were operated over a 2-week period spanning August and September of 2002. The method of cross correlating the outputs of two interferometers is used for analysis. We describe in detail practical signal processing issues that arise when working with real data, and we establish an observational upper limit on a f^-3 power spectrum of gravitational waves. Our 90% confidence limit is Ω0h100(^2)<~23±4.6 in the frequency band 40–314 Hz, where h100 is the Hubble constant in units of 100 km/sec/Mpc and Ω0 is the gravitational wave energy density per logarithmic frequency interval in units of the closure density. This limit is approximately 104 times better than the previous, broadband direct limit using interferometric detectors, and nearly 3 times better than the best narrow-band bar detector limit. As LIGO and other worldwide detectors improve in sensitivity and attain their design goals, the analysis procedures described here should lead to stochastic background sensitivity levels of astrophysical interest.

Seismic isolation and suspension systems for Advanced LIGO

Abstract: To meet the overall isolation and alignment requirements for the optics in Advanced LIGO, the planned upgrade to LIGO, the US laser interferometric gravitational wave observatory, we are developing three sub-systems: a hydraulic external pre-isolator for low frequency alignment and control, a two-stage active isolation platform designed to give a factor of ~1000 attenuation at 10 Hz, and a multiple pendulum suspension system that provides passive isolation above a few hertz. The hydraulic stage uses laminar-flow quiet hydraulic actuators with millimeter range, and provides isolation and alignment for the optics payload below 10 Hz, including correction for measured Earth tides and the microseism. This stage supports the in-vacuum two-stage active isolation platform, which reduces vibration using force feedback from inertial sensor signals in six degrees of freedom. The platform provides a quiet, controlled structure to mount the suspension system. This latter system has been developed from the triple pendulum suspension used in GEO 600, the German/UK gravitational wave detector. To meet the more stringent noise levels required in Advanced LIGO, the baseline design for the most sensitive optics calls for a quadruple pendulum, whose final stage consists of a 40 kg sapphire mirror suspended on fused silica ribbons to reduce suspension thermal noise.

Upper limits on the strength of periodic gravitational waves from PSR J1939+2134

Abstract: The first science run of the LIGO and GEO gravitational wave detectors presented the opportunity to test methods of searching for gravitational waves from known pulsars. Here we present new direct upper limits on the strength of waves from the pulsar PSR J1939+2134 using two independent analysis methods, one in the frequency domain using frequentist statistics and one in the time domain using Bayesian inference. Both methods show that the strain amplitude at Earth from this pulsar is less than a few times 10−22.

LIGO: S1 Science Results and Plans Beyond

Abstract: B. Abbott, R. Abbott, R. Adhikari, A. Ageev, 28 B. Allen, R. Amin, S. B. Anderson, W. G. Anderson, M. Araya, H. Armandula, F. Asiri, a P. Aufmuth, C. Aulbert, S. Babak, R. Balasubramanian, S. Ballmer, B. C. Barish, D. Barker, C. Barker-Patton, M. Barnes, B. Barr, M. A. Barton, K. Bayer, R. Beausoleil, b K. Belczynski, R. Bennett, c S. J. Berukoff, d J. Betzwieser, B. Bhawal, I. A. Bilenko, G. Billingsley, E. Black, K. Blackburn, B. Bland-Weaver, B. Bochner, e L. Bogue, R. Bork, S. Bose, P. R. Brady, V. B. Braginsky, J. E. Brau, D. A. Brown, S. Brozek, f A. Bullington, A. Buonanno, g R. Burgess, D. Busby, W. E. Butler, R. L. Byer, L. Cadonati, G. Cagnoli, J. B. Camp, C. A. Cantley, L. Cardenas, K. Carter, M. M. Casey, J. Castiglione, A. Chandler, J. Chapsky, h P. Charlton, S. Chatterji, Y. Chen, V. Chickarmane, D. Chin, N. Christensen, D. Churches, C. Colacino, 2 R. Coldwell, M. Coles, i D. Cook, T. Corbitt, D. Coyne, J. D. E. Creighton, T. D. Creighton, D. R. M. Crooks, P. Csatorday, B. J. Cusack, C. Cutler, E. D’Ambrosio, K. Danzmann, 2, 20 R. Davies, E. Daw, j D. DeBra, T. Delker, k R. DeSalvo, S. Dhurandhar, M. Diaz, H. Ding, R. W. P. Drever, R. J. Dupuis, C. Ebeling, J. Edlund, P. Ehrens, E. J. Elliffe, T. Etzel, M. Evans, T. Evans, C. Fallnich, D. Farnham, M. M. Fejer, M. Fine, L. S. Finn, E. Flanagan, A. Freise, l R. Frey, P. Fritschel, V. Frolov, M. Fyffe, K. S. Ganezer, J. A. Giaime, A. Gillespie, m K. Goda, G. Gonzalez, S. Gosler, P. Grandclement, A. Grant, C. Gray, A. M. Gretarsson, D. Grimmett, H. Grote, S. Grunewald, M. Guenther, E. Gustafson, n R. Gustafson, W. O. Hamilton, M. Hammond, J. Hanson, C. Hardham, G. Harry, A. Hartunian, J. Heefner, Y. Hefetz, G. Heinzel, I. S. Heng, M. Hennessy, N. Hepler, A. Heptonstall, M. Heurs, M. Hewitson, N. Hindman, P. Hoang, J. Hough, M. Hrynevych, o W. Hua, R. Ingley, M. Ito, Y. Itoh, A. Ivanov, O. Jennrich, p W. W. Johnson, W. Johnston, L. Jones, D. Jungwirth, q V. Kalogera, E. Katsavounidis, K. Kawabe, 2 S. Kawamura, W. Kells, J. Kern, A. Khan, S. Killbourn, C. J. Killow, C. Kim, C. King, P. King, S. Klimenko, P. Kloevekorn, S. Koranda, K. Kotter, J. Kovalik, D. Kozak, B. Krishnan, M. Landry, J. Langdale, B. Lantz, R. Lawrence, A. Lazzarini, M. Lei, V. Leonhardt, I. Leonor, K. Libbrecht, P. Lindquist, S. Liu, J. Logan, r M. Lormand, M. Lubinski, H. Luck, 2 T. T. Lyons, r B. Machenschalk, M. MacInnis, M. Mageswaran, K. Mailand, W. Majid, h M. Malec, F. Mann, A. Marin, s S. Marka, E. Maros, J. Mason, t K. Mason, O. Matherny, L. Matone, N. Mavalvala, R. McCarthy, D. E. McClelland, M. McHugh, P. McNamara, u G. Mendell, S. Meshkov, C. Messenger, V. P. Mitrofanov, G. Mitselmakher, R. Mittleman, O. Miyakawa, S. Miyoki, v S. Mohanty, w G. Moreno, K. Mossavi, B. Mours, x G. Mueller, S. Mukherjee, w J. Myers, S. Nagano, T. Nash, y H. Naundorf, R. Nayak, G. Newton, F. Nocera, P. Nutzman, T. Olson, B. O’Reilly, D. J. Ottaway, A. Ottewill, z D. Ouimette, q H. Overmier, B. J. Owen, M. A. Papa, C. Parameswariah, V. Parameswariah, M. Pedraza, S. Penn, M. Pitkin, M. Plissi, M. Pratt, V. Quetschke, F. Raab, H. Radkins, R. Rahkola, M. Rakhmanov, S. R. Rao, D. Redding, h M. W. Regehr, h T. Regimbau, K. T. Reilly, K. Reithmaier, D. H. Reitze, S. Richman, aa R. Riesen, K. Riles, A. Rizzi, bb D. I. Robertson, N. A. Robertson, 27 L. Robison, S. Roddy, J. Rollins, J. D. Romano, cc J. Romie, H. Rong, m D. Rose, E. Rotthoff, S. Rowan, A. Rudiger, 2 P. Russell, K. Ryan, I. Salzman, G. H. Sanders, V. Sannibale, B. Sathyaprakash, P. R. Saulson, R. Savage, A. Sazonov, R. Schilling, 2 K. Schlaufman, V. Schmidt, dd R. Schofield, M. Schrempel, ee B. F. Schutz, 7 P. Schwinberg, S. M. Scott, A. C. Searle, B. Sears, S. Seel, A. S. Sengupta, C. A. Shapiro, ff P. Shawhan, D. H. Shoemaker, Q. Z. Shu, gg A. Sibley, X. Siemens, L. Sievers, h D. Sigg, A. M. Sintes, 33 K. Skeldon, J. R. Smith, M. Smith, M. R. Smith, P. Sneddon, R. Spero, h G. Stapfer, K. A. Strain, D. Strom, A. Stuver, T. Summerscales, M. C. Sumner, P. J. Sutton, y J. Sylvestre, A. Takamori, D. B. Tanner, H. Tariq, I. Taylor, R. Taylor, K. S. Thorne, M. Tibbits, S. Tilav, hh M. Tinto, h K. V. Tokmakov, C. Torres, C. Torrie, 36 S. Traeger, ii G. Traylor, W. Tyler, D. Ugolini, M. Vallisneri, jj M. van Putten, S. Vass, A. Vecchio, C. Vorvick, S. P. Vyachanin, L. Wallace, H. Walther, H. Ward, B. Ware, h K. Watts, D. Webber, A. Weidner, 2 U. Weiland, A. Weinstein, R. Weiss, H. Welling, L. Wen, S. Wen, J. T. Whelan, S. E. Whitcomb, B. F. Whiting, P. A. Willems, P. R. Williams, kk R. Williams, B. Willke, 2 A. Wilson, B. J. Winjum, d W. Winkler, 2 S. Wise, A. G. Wiseman, G. Woan, R. Wooley, J. Worden, I. Yakushin, H. Yamamoto, S. Yoshida, I. Zawischa, ll L. Zhang, N. Zotov, M. Zucker, and J. Zweizig