The Experts below are selected from a list of 3441 Experts worldwide ranked by ideXlab platform
Giorgio Frossati - One of the best experts on this subject based on the ideXlab platform.
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The Schenberg spherical gravitational wave detector: the first commissioning runs
Classical and Quantum Gravity, 2008Co-Authors: Odylio D. Aguiar, A. De Waard, L A Andrade, Joaquim J. Barroso, Pedro J. Castro, Camila Alves Costa, S.l.t. De Souza, A. C. Fauth, Carlos Frajuca, Giorgio FrossatiAbstract:Here we present a status report of the first spherical antenna project equipped with a set of parametric Transducers for gravitational detection. The Mario Schenberg, as it is called, started its commissioning phase at the Physics Institute of the University of Sao Paulo, in September 2006, under the full support of FAPESP. We have been testing the three preliminary parametric Transducer systems in order to prepare the detector for the next cryogenic run, when it will be calibrated. We are also developing sapphire oscillators that will replace the current ones thereby providing better performance. We also plan to install eight Transducers in the near future, six of which are of the two-mode type and arranged according to the truncated icosahedron configuration. The other two, which will be placed close to the sphere equator, will be mechanically non-Resonant. In doing so, we want to verify that if the Schenberg antenna can become a wideband gravitational wave detector through the use of an ultra-high sensitivity non-Resonant Transducer constructed using the recent achievements of nanotechnology.
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Development of a Transducer for MiniGrail
Classical and Quantum Gravity, 2002Co-Authors: Luciano Gottardi, A. De Waard, Giorgio FrossatiAbstract:We are developing a two-mode inductive Resonant Transducer for MiniGrail. We report several quality factor measurements, down to 4.2 K, performed on a scaled size resonator in different conditions: when suspended from a wire and when clamped, by thermal contraction techniques, into a hole of a sphere of 150 mm diameter and 14 kg mass. Q-factor measurements of a first resonator prototype at 4.2 K for MiniGrail are also presented. Finally, a fabrication process for a Nb film pick-up coil is described.
Antonello Ortolan - One of the best experts on this subject based on the ideXlab platform.
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3-Mode Detection for Widening the Bandwidth of Resonant Gravitational Wave Detectors
Physical Review Letters, 2005Co-Authors: L. Baggio, Michele Bonaldi, Paolo Falferi, Renato Mezzena, M. Bignotto, A. Marin, M. Cerdonio, L. Conti, N. Liguori, Antonello OrtolanAbstract:Along with peak sensitivity, an important parameter of a Resonant gravitational wave detector is its bandwidth. In addition to the obvious advantage of making the detector more sensitive to short bursts, a wider bandwidth would allow, for instance, details of the signal emitted during a supernova gravitational collapse or the merger of compact binaries to be resolved [1]. Moreover, a wider bandwidth reduces the uncertainty in the burst arrival time [2] and consequently, with a detector network, permits a more precise source location and a higher efficiency of spurious events rejection [3]. The introduction of a mechanically Resonant Transducer, a standard practice in actual Resonant detectors, has greatly improved the coupling between the bar and the amplifier, but the bandwidth is intrinsically limited [4], and in practice, according to the full width at half maximum (FWHM) definition applied to the two minima of the Shh strain noise spectra, values of a few Hz have been achieved [5]. The use of multimode Resonant Transducers should permit further improvements of the detector bandwidth [6]. This approach has been studied [7] in depth and a few 2-mode Transducer prototypes have been realized [8] or are under development [9] to obtain 3mode operation of the Resonant mass detectors. This Letter describes how a wider detection bandwidth can be obtained with an alternative 2-mode transduction system in which the Resonant amplification is realized by means of a Resonant mechanical mode plus a Resonant electrical matching network. It also describes the key tests performed on the components of the transduction system in order to verify the achievement of the requirements set by analysis of the detector model. Figure 1 shows the electromechanical scheme of a cryogenic detector with a Resonant capacitive Transducer read by a SQUID amplifier. The matching transformer couples the output impedance of the Transducer (a capacitance of a few nF) to the input impedance of the SQUID (a small
Peter C. Hauser - One of the best experts on this subject based on the ideXlab platform.
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Piezoelectric Tube as Resonant Transducer for Gas-Phase Photoacoustics
Analytica chimica acta, 2020Co-Authors: Kanchalar Keeratirawee, Peter C. HauserAbstract:Abstract The use of a piezoelectric tube for the photoacoustic gas-phase determination of NO2 as a model analyte is demonstrated. The tube is made from lead zirconate titanate with 30 mm length and 5.35 mm internal diameter. Its inner and outer surfaces are coated with electrodes. The tube serves as both, resonance body and Transducer. The design is thus simpler than the usual combination of resonance tube and microphone as the two functions are embodied in the same component. The main resonance frequency of the tube was found to be 5341 Hz. A blue laser diode emitting at 450 nm was employed as light source for the determination of NO2. The limit of detection was determined as 83 ppbV and the calibration curve was linear with a coefficient of determination (r2) of 0.9998 up to the highest concentration of 15 ppmV tested.
Paolo Falferi - One of the best experts on this subject based on the ideXlab platform.
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3-Mode Detection for Widening the Bandwidth of Resonant Gravitational Wave Detectors
Physical Review Letters, 2005Co-Authors: L. Baggio, Michele Bonaldi, Paolo Falferi, Renato Mezzena, M. Bignotto, A. Marin, M. Cerdonio, L. Conti, N. Liguori, Antonello OrtolanAbstract:Along with peak sensitivity, an important parameter of a Resonant gravitational wave detector is its bandwidth. In addition to the obvious advantage of making the detector more sensitive to short bursts, a wider bandwidth would allow, for instance, details of the signal emitted during a supernova gravitational collapse or the merger of compact binaries to be resolved [1]. Moreover, a wider bandwidth reduces the uncertainty in the burst arrival time [2] and consequently, with a detector network, permits a more precise source location and a higher efficiency of spurious events rejection [3]. The introduction of a mechanically Resonant Transducer, a standard practice in actual Resonant detectors, has greatly improved the coupling between the bar and the amplifier, but the bandwidth is intrinsically limited [4], and in practice, according to the full width at half maximum (FWHM) definition applied to the two minima of the Shh strain noise spectra, values of a few Hz have been achieved [5]. The use of multimode Resonant Transducers should permit further improvements of the detector bandwidth [6]. This approach has been studied [7] in depth and a few 2-mode Transducer prototypes have been realized [8] or are under development [9] to obtain 3mode operation of the Resonant mass detectors. This Letter describes how a wider detection bandwidth can be obtained with an alternative 2-mode transduction system in which the Resonant amplification is realized by means of a Resonant mechanical mode plus a Resonant electrical matching network. It also describes the key tests performed on the components of the transduction system in order to verify the achievement of the requirements set by analysis of the detector model. Figure 1 shows the electromechanical scheme of a cryogenic detector with a Resonant capacitive Transducer read by a SQUID amplifier. The matching transformer couples the output impedance of the Transducer (a capacitance of a few nF) to the input impedance of the SQUID (a small
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Advanced Readout Configurations for the Gravitational Wave Detector AURIGA
Recent Developments in General Relativity Genoa 2000, 2002Co-Authors: J.-r Zendri, Massimo Cerdonio, Michele Bonaldi, Paolo Falferi, M. Bignotto, Livia Conti, V. Crivelli Visconti, M. De Rosa, A. Marin, Francesco MarinAbstract:We report the status of the experimental effort devoted at improving the sensitivity and widening the band of the gravitational wave detector AURIGA. The focus is on an optimized setup of the capacitive Resonant Transducer, read by an improved dc-SQUID amplifier and on the implementation of an opto-mechanical Resonant Transducer. Both techniques, which are complementary, should lead to an improvement of the detector performances of at least two orders of magnitude in both energy sensitivity and bandwidth.
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The Auriga ultracryogenic test facility: A new capacitive Resonant Transducer
AIP Conference Proceedings, 2000Co-Authors: V. Crivelli-visconti, J. P. Zendri, L. Taffarello, G. A. Prodi, S. Vitale, Massimo Cerdonio, Michele Bonaldi, Paolo Falferi, Renato Mezzena, A. MattioliAbstract:Sensitivity of presently working gravitational wave Resonant detectors is limited by the transduction chain—Resonant Transducer, impedance matching circuits and SQUIDs. For this reason the Auriga collaboration has started in 1998 the construction of an ultracryogenic test facility where the entire transduction chain can be tested and improved. Mechanical isolation will easely allow for intrinsic thermal noise measurement. In this poster we present the design and first measurements of a new Resonant capacitive Transducer, intended to widen the detector bandwidth up to 50 Hz with the available new generation of SQUIDs.
Michele Bonaldi - One of the best experts on this subject based on the ideXlab platform.
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3-Mode Detection for Widening the Bandwidth of Resonant Gravitational Wave Detectors
Physical Review Letters, 2005Co-Authors: L. Baggio, Michele Bonaldi, Paolo Falferi, Renato Mezzena, M. Bignotto, A. Marin, M. Cerdonio, L. Conti, N. Liguori, Antonello OrtolanAbstract:Along with peak sensitivity, an important parameter of a Resonant gravitational wave detector is its bandwidth. In addition to the obvious advantage of making the detector more sensitive to short bursts, a wider bandwidth would allow, for instance, details of the signal emitted during a supernova gravitational collapse or the merger of compact binaries to be resolved [1]. Moreover, a wider bandwidth reduces the uncertainty in the burst arrival time [2] and consequently, with a detector network, permits a more precise source location and a higher efficiency of spurious events rejection [3]. The introduction of a mechanically Resonant Transducer, a standard practice in actual Resonant detectors, has greatly improved the coupling between the bar and the amplifier, but the bandwidth is intrinsically limited [4], and in practice, according to the full width at half maximum (FWHM) definition applied to the two minima of the Shh strain noise spectra, values of a few Hz have been achieved [5]. The use of multimode Resonant Transducers should permit further improvements of the detector bandwidth [6]. This approach has been studied [7] in depth and a few 2-mode Transducer prototypes have been realized [8] or are under development [9] to obtain 3mode operation of the Resonant mass detectors. This Letter describes how a wider detection bandwidth can be obtained with an alternative 2-mode transduction system in which the Resonant amplification is realized by means of a Resonant mechanical mode plus a Resonant electrical matching network. It also describes the key tests performed on the components of the transduction system in order to verify the achievement of the requirements set by analysis of the detector model. Figure 1 shows the electromechanical scheme of a cryogenic detector with a Resonant capacitive Transducer read by a SQUID amplifier. The matching transformer couples the output impedance of the Transducer (a capacitance of a few nF) to the input impedance of the SQUID (a small
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Advanced Readout Configurations for the Gravitational Wave Detector AURIGA
Recent Developments in General Relativity Genoa 2000, 2002Co-Authors: J.-r Zendri, Massimo Cerdonio, Michele Bonaldi, Paolo Falferi, M. Bignotto, Livia Conti, V. Crivelli Visconti, M. De Rosa, A. Marin, Francesco MarinAbstract:We report the status of the experimental effort devoted at improving the sensitivity and widening the band of the gravitational wave detector AURIGA. The focus is on an optimized setup of the capacitive Resonant Transducer, read by an improved dc-SQUID amplifier and on the implementation of an opto-mechanical Resonant Transducer. Both techniques, which are complementary, should lead to an improvement of the detector performances of at least two orders of magnitude in both energy sensitivity and bandwidth.
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The Auriga ultracryogenic test facility: A new capacitive Resonant Transducer
AIP Conference Proceedings, 2000Co-Authors: V. Crivelli-visconti, J. P. Zendri, L. Taffarello, G. A. Prodi, S. Vitale, Massimo Cerdonio, Michele Bonaldi, Paolo Falferi, Renato Mezzena, A. MattioliAbstract:Sensitivity of presently working gravitational wave Resonant detectors is limited by the transduction chain—Resonant Transducer, impedance matching circuits and SQUIDs. For this reason the Auriga collaboration has started in 1998 the construction of an ultracryogenic test facility where the entire transduction chain can be tested and improved. Mechanical isolation will easely allow for intrinsic thermal noise measurement. In this poster we present the design and first measurements of a new Resonant capacitive Transducer, intended to widen the detector bandwidth up to 50 Hz with the available new generation of SQUIDs.