Astrophysics and Astronomy | Open Access Articles

Upper Limits On Gravitational Wave Bursts In Ligo’S Second Science Run, B. P. Abbott, R. Abbott, W. G. Anderson, Mario C. Diaz, Wm. R. Johnston, Soumya Mohanty, Soma Mukherjee, Cristina V. Torres

Physics & Astronomy Faculty Publications

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 100–1100 Hz 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 rate, O ( 0.1 ) μ …

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Search For Gravitational Waves From Primordial Black Hole Binary Coalescences In The Galactic Halo, B. P. Abbott, R. Abbott, Mario C. Diaz, Wm. R. Johnston, Soma Mukherjee, Soumya Mohanty, Cristina V. Torres

Physics & Astronomy Faculty Publications

We use data from the second science run of the LIGO gravitational-wave detectors to search for the gravitational waves from primordial black hole binary coalescence with component masses in the range 0.2–1.0M⊙. The analysis requires a signal to be found in the data from both LIGO observatories, according to a set of coincidence criteria. No inspiral signals were found. Assuming a spherical halo with core radius 5 kpc extending to 50 kpc containing nonspinning black holes with masses in the range 0.2–1.0M⊙, we place an observational upper limit on the rate of primordial black hole coalescence of 63 per year …

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Response Of Test Masses To Gravitational Waves In The Local Lorentz Gauge, Malik Rakhmanov

Physics & Astronomy Faculty Publications

The local Lorentz gauge represents a natural coordinate frame for an observer to analyze the effect of gravitational waves on detectors, and has been widely used to describe the response of resonant bars. Its application to laser interferometers has thus far been restricted to the long-wavelength regime, in which the separation between the test masses is much less than the wavelength of the gravitational waves. In this paper we show that the local Lorentz gauge can be used for calculations of geodesic deviations of the masses even when their separation is comparable to or greater than the wavelength of the …

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Higher Twist Analysis Of The Proton G₁ Structure Function, M. Osipenko, W. Melnitchouk, S. Simula, P. Bosted, V. Burkert, M. E. Christy, K. Griffioen, C. Keppel, S. E. Kuhn

Physics Faculty Publications

We perform a global analysis of all available spin-dependent proton structure function data, covering a large range of Q², 1 ⩽ Q² ⩽ 30 GeV², and calculate the lowest moment of the g₁ structure function as a function of Q². From the Q² dependence of the lowest moment we extract matrix elements of twist-4 operators, and determine the color electric and magnetic polarizabilities of the proton to be X_E= 0.026 ± 0.015(stat) ± ^0.021_0.024 (sys) and X_B= -0.013 ∓ 0.007(stat) ∓ ^0.010 _0.012(sys), respectively.

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Search For Gravitational Waves Associated With The Gamma Ray Burst Grb030329 Using The Ligo Detectors, B. P. Abbott, R. Abbott, Mario C. Diaz, Wm. R. Johnston, Soumya Mohanty, Soma Mukherjee, Cristina V. Torres

Physics & Astronomy Faculty Publications

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 predetermined threshold. We report frequency-dependent upper limits on the strength of the gravitational waves associated with …

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Electric-Field Generated By The Combustion Of Titanium In Nitrogen, Karen S. Martirosyan, Mona Setoodeh, Dan Luss

Physics & Astronomy Faculty Publications

A short temporal electrical impulse (duration of 30–150ms) was generated during the nitridation of mixtures of titanium and titanium nitride by a high temperature moving reaction front. The maximum voltage and current were generated in the combustion front region, in which the conversion of Ti to TiN was incomplete. The electric field (voltage up to 2V and current up to 60mA) decayed and vanished before the maximum combustion temperature was attained. The generation of an electric field during a rapid high-temperature nitridation is most probably due to the different diffusion velocities of charge carriers through the growing titanium nitride shell …

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First All-Sky Upper Limits From Ligo On The Strength Of Periodic Gravitational Waves Using The Hough Transform, B. P. Abbott, R. Abbott, W. G. Anderson, Mario C. Diaz, Wm. R. Johnston, Soma Mukherjee, Soumya Mohanty, Cristina V. Torres

Physics & Astronomy Faculty Publications

We perform a wide parameter-space search for continuous gravitational waves over the whole sky and over a large range of values of the frequency and the first spin-down parameter. Our search method is based on the Hough transform, which is a semicoherent, computationally efficient, and robust pattern recognition technique. We apply this technique to data from the second science run of the LIGO detectors and our final results are all-sky upper limits on the strength of gravitational waves emitted by unknown isolated spinning neutron stars on a set of narrow frequency bands in the range 200–400 Hz. The best upper …

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Limits On Gravitational-Wave Emission From Selected Pulsars Using Ligo Data, B. P. Abbott, R. Abbott, Mario C. Diaz, Wm. R. Johnston, Soumya Mohanty, Soma Mukherjee, Cristina V. Torres

Physics & Astronomy Faculty Publications

We place direct upper limits on the amplitude of gravitational waves from 28 isolated radio pulsars by a coherent multidetector analysis of the data collected during the second science run of the LIGO interferometric detectors. These are the first direct upper limits for 26 of the 28 pulsars. We use coordinated radio observations for the first time to build radio-guided phase templates for the expected gravitational-wave signals. The unprecedented sensitivity of the detectors allows us to set strain upper limits as low as a few times 10−24. These strain limits translate into limits on the equatorial ellipticities of the pulsars, …

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Exclusive Ρ0 Meson Electroproduction From Hydrogen At Clas, C. Hadjidakis, M. Guidal, M. Garçon, J.-M. Laget, E. S. Smith, M. Vanderhaeghen, G. Adams, P. Ambrozewicz, E. Anciant, M. Anghinolfi, H. Bagdasaryan, K. V. Dharmawardane, G. E. Dodge, T. A. Forest, G. Gavalian, M. Guler, C. E. Hyde-Wright, A. Klein, A. V. Klimenko, S. E. Kuhn, R. A. Niyazov, L. M. Qin, F. Sabatie, L. B. Weinstein, J. Yun

Physics Faculty Publications

The longitudinal and transverse components of the cross section for the ep → e′ pρ⁰ reaction were measured in Hall B at Jefferson Laboratory using the CLAS detector. The data were taken with a 4.247 GeV electron beam and were analyzed in a range of ^xB from 0.2 to 0.6 and of Q² from 1.5 to 3.0 GeV2. The data are compared to a Regge model based on effective hadronic degrees of freedom and to a calculation based on Generalized Parton Distributions. It is found that, at our lowest ^xB values, the transverse part of the …

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Full-Text Articles in Astrophysics and Astronomy

Upper Limits On Gravitational Wave Bursts In Ligo’S Second Science Run, B. P. Abbott, R. Abbott, W. G. Anderson, Mario C. Diaz, Wm. R. Johnston, Soumya Mohanty, Soma Mukherjee, Cristina V. Torres

Physics & Astronomy Faculty Publications

Search For Gravitational Waves From Primordial Black Hole Binary Coalescences In The Galactic Halo, B. P. Abbott, R. Abbott, Mario C. Diaz, Wm. R. Johnston, Soma Mukherjee, Soumya Mohanty, Cristina V. Torres

Physics & Astronomy Faculty Publications

Response Of Test Masses To Gravitational Waves In The Local Lorentz Gauge, Malik Rakhmanov

Physics & Astronomy Faculty Publications

Higher Twist Analysis Of The Proton G₁ Structure Function, M. Osipenko, W. Melnitchouk, S. Simula, P. Bosted, V. Burkert, M. E. Christy, K. Griffioen, C. Keppel, S. E. Kuhn

Physics Faculty Publications

Search For Gravitational Waves Associated With The Gamma Ray Burst Grb030329 Using The Ligo Detectors, B. P. Abbott, R. Abbott, Mario C. Diaz, Wm. R. Johnston, Soumya Mohanty, Soma Mukherjee, Cristina V. Torres

Physics & Astronomy Faculty Publications

Electric-Field Generated By The Combustion Of Titanium In Nitrogen, Karen S. Martirosyan, Mona Setoodeh, Dan Luss

Physics & Astronomy Faculty Publications

First All-Sky Upper Limits From Ligo On The Strength Of Periodic Gravitational Waves Using The Hough Transform, B. P. Abbott, R. Abbott, W. G. Anderson, Mario C. Diaz, Wm. R. Johnston, Soma Mukherjee, Soumya Mohanty, Cristina V. Torres

Physics & Astronomy Faculty Publications

Limits On Gravitational-Wave Emission From Selected Pulsars Using Ligo Data, B. P. Abbott, R. Abbott, Mario C. Diaz, Wm. R. Johnston, Soumya Mohanty, Soma Mukherjee, Cristina V. Torres

Physics & Astronomy Faculty Publications

Physics Faculty Publications