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Petoukhov AK, Nesvizhevsky VV, Bigault T, Courtois P, Devishvili A, Jullien D, Soldner T. Realization of an advanced super-mirror solid-state neutron polarizer for the instrument PF1B at the Institut Laue-Langevin. Rev Sci Instrum 2023; 94:023304. [PMID: 36859054 DOI: 10.1063/5.0123419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 01/10/2023] [Indexed: 06/18/2023]
Abstract
In this last of a series of three papers on the development of an advanced solid-state neutron polarizer, we present the final construction of the polarizer and the results of its commissioning. The polarizer uses spin-selective reflection of neutrons by interfaces coated with polarizing super-mirrors. The polarizer is built entirely in-house for the PF1B cold neutron beam facility at the Institut Max von Laue-Paul Langevin (ILL). It has been installed in the PF1B casemate and tested under real conditions. The average transmission for the "good" spin component is measured to be >30%. The polarization averaged over the capture spectrum reaches a record value of Pn ≈ 0.997 for the full angular divergence in the neutron beam, delivered by the H113 neutron guide, and the full wavelength band λ of 0.3-2.0 nm. This unprecedented performance is due to a series of innovations in the design and fabrication in the following domains: choice of the substrate material, super-mirror and anti-reflecting multilayer coatings, magnetizing field, and assembling process. The polarizer is used for user experiments at PF1B since the last reactor cycle in 2020.
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Affiliation(s)
- A K Petoukhov
- Institut Max von Laue - Paul Langevin, 71 avenue des Martyrs, 38042 Grenoble, France
| | - V V Nesvizhevsky
- Institut Max von Laue - Paul Langevin, 71 avenue des Martyrs, 38042 Grenoble, France
| | - T Bigault
- Institut Max von Laue - Paul Langevin, 71 avenue des Martyrs, 38042 Grenoble, France
| | - P Courtois
- Institut Max von Laue - Paul Langevin, 71 avenue des Martyrs, 38042 Grenoble, France
| | - A Devishvili
- Institut Max von Laue - Paul Langevin, 71 avenue des Martyrs, 38042 Grenoble, France
| | - D Jullien
- Institut Max von Laue - Paul Langevin, 71 avenue des Martyrs, 38042 Grenoble, France
| | - T Soldner
- Institut Max von Laue - Paul Langevin, 71 avenue des Martyrs, 38042 Grenoble, France
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Chernyavsky SM, Dubois M, Korobkina E, Lychagin EV, Muzychka AY, Nekhaev GV, Nesvizhevsky VV, Nezvanov AY, Strelkov AV, Zhernenkov KN. Enhanced directional extraction of very cold neutrons using a diamond nanoparticle powder reflector. Rev Sci Instrum 2022; 93:123302. [PMID: 36586889 DOI: 10.1063/5.0124833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Accepted: 11/09/2022] [Indexed: 06/17/2023]
Abstract
For more than a decade, detonation nanodiamond (DND) powders have been actively studied as a material for efficient reflectors of very cold neutrons (VCNs) and cold neutrons. In this work, we experimentally demonstrate, for the first time, the possibility of enhanced directional extraction of a VCN beam using a reflector made of fluorinated DND powder. With respect to the theoretical flux calculated from an isotropic source at the bottom of the reflector cavity, the gain in the VCN flux density along the beam axis is ∼10 for the neutron velocities of ∼57 and ∼75 m/s. The use of such reflectors for enhanced directional extraction of VCN from neutron sources will make it possible to noticeably increase the neutron fluxes delivered to experiments and expand the scope of VCN applications.
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Affiliation(s)
- S M Chernyavsky
- National Research Center "Kurchatov Institute," 123182 Moscow, Russia
| | - M Dubois
- Université Clermont Auvergne, Clermont Auvergne INP, Institut de Chimie de Clermont-Ferrand (ICCF UMR 6296), CNRS, 63178 Auvergne, France
| | - E Korobkina
- NC State University, Raleigh, North Carolina 27695-710, USA
| | - E V Lychagin
- Joint Institute for Nuclear Research, 141980 Dubna, Russia
| | - A Yu Muzychka
- Joint Institute for Nuclear Research, 141980 Dubna, Russia
| | - G V Nekhaev
- Joint Institute for Nuclear Research, 141980 Dubna, Russia
| | | | - A Yu Nezvanov
- Joint Institute for Nuclear Research, 141980 Dubna, Russia
| | - A V Strelkov
- Joint Institute for Nuclear Research, 141980 Dubna, Russia
| | - K N Zhernenkov
- Joint Institute for Nuclear Research, 141980 Dubna, Russia
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Tutunnikov I, Rajitha KV, Voronin AY, Nesvizhevsky VV, Averbukh IS. Impulsively Excited Gravitational Quantum States: Echoes and Time-Resolved Spectroscopy. Phys Rev Lett 2021; 126:170403. [PMID: 33988422 DOI: 10.1103/physrevlett.126.170403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Revised: 12/18/2020] [Accepted: 03/29/2021] [Indexed: 06/12/2023]
Abstract
We theoretically study an impulsively excited quantum bouncer (QB)-a particle bouncing off a surface in the presence of gravity. A pair of time-delayed pulsed excitations is shown to induce a wave-packet echo effect-a partial rephasing of the QB wave function appearing at twice the delay between pulses. In addition, an appropriately chosen observable [here, the population of the ground gravitational quantum state (GQS)] recorded as a function of the delay is shown to contain the transition frequencies between the GQSs, their populations, and partial phase information about the wave-packet quantum amplitudes. The wave-packet echo effect is a promising candidate method for precision studies of GQSs of ultracold neutrons, atoms, and antiatoms confined in closed gravitational traps.
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Affiliation(s)
- I Tutunnikov
- AMOS and Department of Chemical and Biological Physics, The Weizmann Institute of Science, Rehovot 7610001, Israel
| | - K V Rajitha
- AMOS and Department of Chemical and Biological Physics, The Weizmann Institute of Science, Rehovot 7610001, Israel
| | - A Yu Voronin
- P. N. Lebedev Physical Institute, 53 Leninsky Prospect, Moscow Ru-119333, Russia
| | - V V Nesvizhevsky
- Institut Max von Laue-Paul Langevin (ILL), 71 avenue des Martyrs, F-38042 Grenoble, France
| | - I Sh Averbukh
- AMOS and Department of Chemical and Biological Physics, The Weizmann Institute of Science, Rehovot 7610001, Israel
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Petukhov AK, Nesvizhevsky VV, Bigault T, Courtois P, Jullien D, Soldner T. A project of advanced solid-state neutron polarizer for PF1B instrument at Institut Laue-Langevin. Rev Sci Instrum 2019; 90:085112. [PMID: 31472636 DOI: 10.1063/1.5114796] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 08/06/2019] [Indexed: 06/10/2023]
Abstract
Among polarizers based on the neutron reflection from Super-Mirrors (SMs), solid-state neutron-optical devices have many advantages. The most relevant is the 5-10 times smaller size along the neutron beam direction compared to more traditional air-gap devices. An important condition for a good SM polarizer is the matching of the substrate SLD (Scattering Length Density) with the SM coating SLD for the spin-down component. For traditional Fe/Si SM on the Si substrate, this SLD step is positive when a neutron goes from the substrate to the SM, which leads to a significant degradation of the polarizer performance in the small Q region. This can be solved by replacing single-crystal Si substrates by single-crystal sapphire or quartz substrates. The latter shows a negative SLD step for the spin-down neutron polarization component at the interface with Fe and, therefore, avoid the total reflection regime in the small Q region. In order to optimize the polarizer performance, we formulate the concept of sapphire V-bender. We perform ray-tracing simulations of sapphire V-bender, compare results with those for traditional C-bender on Si, and study experimentally V-bender prototypes with different substrates. Our results show that the choice of substrate material, polarizer geometry, as well the strength and quality of magnetizing field have dramatic effect on the polarizer performance. In particular, we compare the performance of polarizer for the applied magnetic field strength of 50 mT and 300 mT. Only the large field strength (300 mT) provides an excellent agreement between the simulated and measured polarization values. For the double-reflection configuration, a record polarization >0.999 was obtained in the neutron wavelength band of 0.3-1.2 nm with only 1% decrease at 2 nm. Without any collimation, the polarization averaged over the full outgoing capture spectrum, 0.997, was found to be equal to the value obtained previously using only a double polarizer in the "crossed" (X-SM) geometry. These results are applied in a full-scale polarizer for the PF1B instrument.
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Affiliation(s)
- A K Petukhov
- Institut Max von Laue-Paul Langevin, 71 avenue des Martyrs, Grenoble F-38042, France
| | - V V Nesvizhevsky
- Institut Max von Laue-Paul Langevin, 71 avenue des Martyrs, Grenoble F-38042, France
| | - T Bigault
- Institut Max von Laue-Paul Langevin, 71 avenue des Martyrs, Grenoble F-38042, France
| | - P Courtois
- Institut Max von Laue-Paul Langevin, 71 avenue des Martyrs, Grenoble F-38042, France
| | - D Jullien
- Institut Max von Laue-Paul Langevin, 71 avenue des Martyrs, Grenoble F-38042, France
| | - T Soldner
- Institut Max von Laue-Paul Langevin, 71 avenue des Martyrs, Grenoble F-38042, France
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Nesvizhevsky VV, Gudkov V, Protasov KV, Snow WM, Voronin AY. Experimental Approach to Search for Free Neutron-Antineutron Oscillations Based on Coherent Neutron and Antineutron Mirror Reflection. Phys Rev Lett 2019; 122:221802. [PMID: 31283255 DOI: 10.1103/physrevlett.122.221802] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 02/06/2019] [Indexed: 06/09/2023]
Abstract
An observation of neutron-antineutron oscillations (n-n[over ¯]), which violate both B and B-L conservation, would constitute a scientific discovery of fundamental importance to physics and cosmology. A stringent upper bound on its transition rate would make an important contribution to our understanding of the baryon asymmetry of the Universe by eliminating the postsphaleron baryogenesis scenario in the light quark sector. We show that one can design an experiment using slow neutrons that in principle can reach the required sensitivity of τ_{n-n[over ¯]}∼10^{10} s in the oscillation time, an improvement of ∼10^{4} in the oscillation probability relative to the existing limit for free neutrons. The improved statistical accuracy needed to reach this sensitivity can be achieved by allowing both the neutron and antineutron components of the developing superposition state to coherently reflect from mirrors. We present a quantitative analysis of this scenario and show that, for sufficiently small transverse momenta of n/n[over ¯] and for certain choices of nuclei for the n/n[over ¯] guide material, the relative phase shift of the n and n[over ¯] components upon reflection and the n[over ¯] annihilation rate can be small enough to maintain sufficient coherence to benefit from the greater phase space acceptance the mirror provides.
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Affiliation(s)
- V V Nesvizhevsky
- Institut Max von Laue-Paul Langevin, 71 avenue des Martyrs, Grenoble, France 38042
| | - V Gudkov
- Department of Physics and Astronomy, University of South Carolina, Columbia, South Carolina 29208, USA
| | - K V Protasov
- Laboratoire de Physique Subatomique et de Cosmologie, UGA-CNRS/IN2P3, Grenoble, France 38026
| | - W M Snow
- Department of Physics, Indiana University, 727 E. Third St., Bloomington, Indiana 47405, USA
| | - A Yu Voronin
- P.N. Lebedev Physical Institute, 53 Leninsky prospect, Moscow, Russia 119991
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Nesvizhevsky VV, Voronin AY, Lambrecht A, Reynaud S, Lychagin EV, Muzychka AY, Nekhaev GV, Strelkov AV. The method of UCN "small heating" measurement in the big gravitational spectrometer (BGS) and studies of this effect on Fomblin oil Y-HVAC 18/8. Rev Sci Instrum 2018; 89:023501. [PMID: 29495873 DOI: 10.1063/1.5010974] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The Big Gravitational Spectrometer (BGS) takes advantage of the strong influence of the Earth's gravity on the motion of ultracold neutrons (UCNs) that makes it possible to shape and measure UCN spectra. We optimized the BGS to investigate the "small heating" of UCNs, that is, the inelastic reflection of UCNs from a surface accompanied by an energy change comparable with the initial UCN energy. UCNs whose energy increases are referred to as "Vaporized UCNs" (VUCNs). The BGS provides the narrowest UCN spectra of a few cm and the broadest "visible" VUCN energy range of up to ∼150 cm (UCN energy is given in units of its maximum height in the Earth's gravitational field, where 1.00 cm ≈ 1.02 neV). The dead-zone between the UCN and VUCN spectra is the narrowest ever achieved (a few cm). We performed measurements with and without samples without breaking vacuum. BGS provides the broadest range of temperatures (77-600 K) and the highest sensitivity to the small heating effect, up to ∼10-8 per bounce, i.e., two orders of magnitude higher than the sensitivity of alternative methods. We describe the method to measure the probability of UCN "small heating" using the BGS and illustrate it with a study of samples of the hydrogen-free oil Fomblin Y-HVAC 18/8. The data obtained are well reproducible, do not depend on sample thickness, and do not evolve over time. The measured model-independent probability P+ of UCN small heating from an energy "mono-line" 30.2 ± 2.5 cm to the energy range 35-140 cm is in the range 1.05±0.02stat×10-5-1.31±0.24stat×10-5 at a temperature of 24 °C. The associated systematic uncertainty would disappear if a VUCN spectrum shape were known, for instance, from a particular model of small heating. This experiment provides the most precise and reliable value of small heating probability on Fomblin measured so far. These results are of importance for studies of UCN small heating as well as for analyzing and designing neutron lifetime experiments.
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Affiliation(s)
| | | | - A Lambrecht
- Laboratoire Kastler Brossel, UPMC-Sorbonne Université, CNRS, ENS-PSL Research University, Collège de France, Campus Jussieu, 75252 Paris, France
| | - S Reynaud
- Laboratoire Kastler Brossel, UPMC-Sorbonne Université, CNRS, ENS-PSL Research University, Collège de France, Campus Jussieu, 75252 Paris, France
| | - E V Lychagin
- Joint Institute for Nuclear Research, 141980 Dubna, Russia
| | - A Yu Muzychka
- Joint Institute for Nuclear Research, 141980 Dubna, Russia
| | - G V Nekhaev
- Joint Institute for Nuclear Research, 141980 Dubna, Russia
| | - A V Strelkov
- Joint Institute for Nuclear Research, 141980 Dubna, Russia
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Artem’ev VA, Nezvanov AY, Nesvizhevsky VV. Precise calculations in simulations of the interaction of low energy neutrons with nano-dispersed media. CRYSTALLOGR REP+ 2016. [DOI: 10.1134/s1063774516010028] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Nesvizhevsky VV, Voronin AY, Lambrecht A, Reynaud S, Lychagin EV, Muzychka AY, Strelkov AV. Quantum levitation of nanoparticles seen with ultracold neutrons. CRYSTALLOGR REP+ 2013. [DOI: 10.1134/s1063774513050088] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Arzumanov SS, Bondarenko LN, Geltenbort P, Morozov VI, Nesvizhevsky VV, Panin YN, Strepetov AN, Chuvilin DY. Flexible polyvinyl chloride neutron guides for transporting ultracold and very cold neutrons. CRYSTALLOGR REP+ 2011. [DOI: 10.1134/s1063774511070030] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Krylov AR, Lychagin EV, Muzychka AY, Nesvizhevsky VV, Nekhaev GV, Strelkov AV, Ivanov AS. Study of bound hydrogen in powders of diamond nanoparticles. CRYSTALLOGR REP+ 2011. [DOI: 10.1134/s1063774511070169] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Nesvizhevsky VV, Petukhov AK, Börner HG, Baranova TA, Gagarski AM, Petrov GA, Protasov KV, Voronin AY, Baeßler S, Abele H, Westphal A, Lucovac L. Investigation of the Neutron Quantum States in the Earth's Gravitational Field. J Res Natl Inst Stand Technol 2005; 110:263-267. [PMID: 27308133 PMCID: PMC4849602 DOI: 10.6028/jres.110.036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 08/11/2004] [Indexed: 06/06/2023]
Abstract
We studied the neutron quantum states in the potential well formed by the Earth's gravitational field and a horizontal mirror. The estimated characteristic sizes of the neutron wave functions in two lowest quantum states correspond to their expectations with an accuracy of ≈25 %. The spatial density distribution in a standing neutron wave above a mirror was measured for a set of a few lowest quantum states. A position-sensitive neutron detector with an extra high spatial resolution of 1 μm to 2 μm was developed and tested for this particular task. Although this experiment was not designed or optimized to search for an additional short-range force, nevertheless it allowed us to slightly improve the published boundary in the nanometer range of characteristic distances. We studied systematical uncertainties in the chosen "flow-through" method as well as the feasibility to improve further the accuracy in this experiment.
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Affiliation(s)
| | | | - H G Börner
- ILL, 6 rue Jules Horowitz, Grenoble, France
| | - T A Baranova
- PNPI, Orlova Roscha, Gatchina, Leningrad reg., Russia
| | - A M Gagarski
- PNPI, Orlova Roscha, Gatchina, Leningrad reg., Russia
| | - G A Petrov
- PNPI, Orlova Roscha, Gatchina, Leningrad reg., Russia
| | | | | | - S Baeßler
- University of Mainz, 21 Saarstr., Germany
| | - H Abele
- University of Heidelberg, 1 Grabengasse, Germany
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Nesvizhevsky VV, Protasov KV. Constraints on Non-Newtonian Gravity From the Experiment on Neutron Quantum States in the Earth's Gravitational Field. J Res Natl Inst Stand Technol 2005; 110:269-272. [PMID: 27308134 PMCID: PMC4849603 DOI: 10.6028/jres.110.037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 08/11/2004] [Indexed: 06/06/2023]
Abstract
An upper limit to non-Newtonian attractive forces is obtained from the measurement of quantum states of neutrons in the Earth's gravitational field. This limit improves the existing constraints in the nanometer range.
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Affiliation(s)
| | - K V Protasov
- Laboratoire de Physique Subatomique et de Cosmologie, Grenoble, France
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