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Author Magan, D.L.P.; Caballero, L.; Domingo-Pardo, C.; Agramunt-Ros, J.; Albiol, F.; Casanovas, A.; Gonzalez, A.; Guerrero, C.; Lerendegui-Marco, J.; Tarifeño-Saldivia, A.
Title First tests of the applicability of gamma-ray imaging for background discrimination in time-of-flight neutron capture measurements Type Journal Article
Year 2016 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume (down) 823 Issue Pages 107-119
Keywords Neutron capture cross-sections; gamma-ray imaging; Total energy detectors; Pulse-height weighting technique; Time-of-flight method
Abstract In this work we explore for the first time the applicability of using gamma-ray imaging in neutron capture measurements to identify and suppress spatially localized background. For this aim, a pinhole gamma camera is assembled, tested and characterized in terms of energy and spatial performance. It consists of a monolithic CeBr3 scintillating crystal coupled to a position-sensitive photomultiplier and readout through an integrated circuit AMIC2GR. The pinhole collimator is a massive carven block of lead. A series of dedicated measurements with calibrated sources and with a neutron beam incident on a Au-197 sample have been carried out at n_TOF, achieving an enhancement of a factor of two in the signal-to-background ratio when selecting only those events coming from the direction of the sample.
Address [Perez Magan, D. L.; Caballero, L.; Domingo-Pardo, C.; Agramunt-Ros, J.; Albiol, F.; Tarifeno-Saldivia, A.] Univ Valencia, CSIC, IFIC, E-46071 Valencia, Spain, Email: domingo@ific.uv.es
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN Medium
Area Expedition Conference
Notes WOS:000374661600015 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 2665
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Author Modamio, V.; Valiente-Dobon, J.J.; Jaworski, G.; Huyuk, T.; Triossi, A.; Egea, J.; Di Nitto, A.; Soderstrom, P.A.; Ros, J.A.; de Angelis, G.; de France, G.; Erduran, M.N.; Erturk, S.; Gadea, A.; Gonzalez, V.; Kownacki, J.; Moszynski, M.; Nyberg, J.; Palacz, M.; Sanchis, E.; Wadsworthm, R.
Title Digital pulse-timing technique for the neutron detector array NEDA Type Journal Article
Year 2015 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume (down) 775 Issue Pages 71-76
Keywords Digital timing; Constant fraction discriminator; Liquid scintillator; BC501A; Neutron detector; NEDA
Abstract A new digital pulse-timing algorithm, to be used with the future neutron detector array NEDA, has been developed and tested. The time resolution of four 5 in diameter photomultiplier tubes (XP4512, R4144, R11833-100, and ET9390-kb), coupled to a cylindrical 5 in by 5 in BC501A liquict scintillator detector was measured by employing digital sampling electronics and a constant fraction discriminator (CFD) algorithm. The zero crossing of the CM algorithm was obtained with a cubic spline interpolation, which was continuous up to the second derivative. The performance of the algorithm was studied at sampling rates of 500 MS/s and 200 MS/s. The time resolution obtained with the digital electronics was compared to the values acquired with a standard analog CFD. The result of this comparison shows that the time resolution from the analog and the digital measurements at 500 MS/s and at 200 MS/s are within 15% for all the tested photomultiplier tubes.
Address [Modamio, V.; Valiente-Dobon, J. J.; Triossi, A.; de Angelis, G.] Ist Nazl Fis Nucl, Lab Nazl Legnaro, I-35020 Legnaro, Italy, Email: victor.modamio@lnl.infn.it
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN Medium
Area Expedition Conference
Notes WOS:000348040900011 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2093
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Author Casas, F.; Oteo, J.A.; Ros, J.
Title Unitary transformations depending on a small parameter Type Journal Article
Year 2012 Publication Proceedings of the Royal Society A Abbreviated Journal Proc. R. Soc. A
Volume (down) 468 Issue 2139 Pages 685-700
Keywords perturbation theory; quantum mechanics; unitary transformation; Magnus expansion
Abstract We formulate a unitary perturbation theory for quantum mechanics inspired by the Lie-Deprit formulation of canonical transformations. The original Hamiltonian is converted into a solvable one by a transformation obtained through a Magnus expansion. This ensures unitarity at every order in a small parameter. A comparison with the standard perturbation theory is provided. We work out the scheme up to order ten with some simple examples.
Address [Oteo, J. A.; Ros, J.] Univ Valencia, Dept Fis Teor, E-46100 Valencia, Spain, Email: rosj@uv.es
Corporate Author Thesis
Publisher Royal Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1364-5021 ISBN Medium
Area Expedition Conference
Notes WOS:000300185400005 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 893
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Author Baeza-Ballesteros, J.; Donini, A.; Molina-Terriza, G.; Monrabal, F.; Simon, A.
Title Towards a realistic setup for a dynamical measurement of deviations from Newton's 1/r2 law: the impact of air viscosity Type Journal Article
Year 2024 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume (down) 84 Issue 6 Pages 596 - 20pp
Keywords
Abstract A novel experimental setup to measure deviations from the 1/r(2) distance dependence of Newtonian gravity was proposed in Donini and Marimon (Eur Phys J C 76:696, 2016). The underlying theoretical idea was to study the orbits of a microscopically-sized planetary system composed of a “Satellite”, with mass m(S) similar to O(10-9) g, and a “Planet”, with mass M-P similar to O(10-5) g at an initial distance of hundreds of microns. The detection of precession of the orbit in this system would be an unambiguous indication of a central potential with terms that scale with the distance differently from 1/r. This is a huge advantage with respect to the measurement of the absolute strength of the attraction between two bodies, as most electrically-induced background potentials do indeed scale as 1/r. Detection of orbit precession is unaffected by these effects, allowing for better sensitivities. In Baeza-Ballesteros et al. (Eur Phys J C 82:154, 2022), the impact of other subleading backgrounds that may induce orbit precession, such as, e.g., the electrical Casimir force or general relativity, was studied in detail. It was found that the proposed setup could test Yukawa-like corrections, alpha x exp(-r/lambda), to the 1/r potential with couplings as low as alpha similar to 10(-2) for distances as small as lambda similar to 10 μm, improving by roughly an order of magnitude present bounds. In this paper, we start to move from a theoretical study of the proposal to a more realistic implementation of the experimental setup. As a first step, we study the impact of air viscosity on the proposed setup and see how the setup should be modified in order to preserve the theoretical sensitivity achieved in Donini and Marimon (2016) and Baeza-Ballesteros et al. (2022).
Address [Baeza-Ballesteros, J.; Donini, A.] Univ Valencia, Inst Fis Corpuscular, CSIC, Calle Catedrat Jose Beltran Martinez 2, Paterna 46980, Spain, Email: jorge.baeza@ific.uv.es
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:001243830900015 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6156
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Author Baeza-Ballesteros, J.; Donini, A.; Nadal-Gisbert, S.
Title Dynamical measurements of deviations from Newton's 1/r(2) law Type Journal Article
Year 2022 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume (down) 82 Issue 2 Pages 154 - 30pp
Keywords
Abstract In Ref. Donini and Marimon (Eur Phys J C 76:696, arXiv:1609.05654, 2016), an experimental setup aiming at the measurement of deviations from the Newtonian 1/r(2) distance dependence of gravitational interactions was proposed. The theoretical idea behind this setup was to study the trajectories of a “Satellite” with a mass m(S) similar to O(10(-9)) g around a “Planet” with mass m(P) is an element of [10(-7), 10(-5)] g, looking for precession of the orbit. The observation of such feature induced by gravitational interactions would be an unambiguous indication of a gravitational potential with terms different from 1/r and, thus, a powerful tool to detect deviations from Newton's 1/r(2) law. In this paper we optimize the proposed setup in order to achieve maximal sensitivity to look for such Beyond-Newtonian corrections. We then study in detail possible background sources that could induce precession and quantify their impact on the achievable sensitivity. We finally conclude that a dynamical measurement of deviations from newtonianity can test Yukawa-like corrections to the 1/r potential with strength as low as alpha similar to 10(-2) for distances as small as lambda similar to 10 μm.
Address [Baeza-Ballesteros, J.; Donini, A.; Nadal-Gisbert, S.] Univ Valencia, Inst Fis Corpuscular, CSIC, Paterna 46980, Spain, Email: jorge.baeza@ific.uv.es
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000757843300001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 5147
Permanent link to this record