Нейтроноводная система ультрахолодных и холодных нейтронов на реакторе ВВР-М

AbstractThe results of calculation of fluxes of ultracold (UCNs), very cold, and cold neutrons at the output of neutron guides of the UCN source with superfluid helium at the WWR-M reactor are presented. UCN density ρ_35L = 1.3 × 10^4 n/cm^3 in the trap of the electric dipole moment (EDM) spectrometer was obtained by optimizing source parameters. This UCN density in the EDM spectrometer is two orders of magnitude higher than the UCN density at the output of the available UCN sources. The flux density of cold neutrons with a wavelength of 2–20 Å at the output of a neutron guide with a cross section of 30 × 200 mm^2 should be as high as 1.1 × 10^8 n/(cm^2 s), while the flux density of very cold neutrons (50–100 Å) at the output of the same neutron guide should be 2.3 × 10^5 n/(cm^2 s). An extensive program of fundamental and applied physical research was mapped out for this source.

Download Full-text

Development of a powerful UCN source at PNPI's WWR-M reactor

EPJ Web of Conferences ◽

10.1051/epjconf/201921910002 ◽

2019 ◽

Vol 219 ◽

pp. 10002 ◽

Cited By ~ 1

Author(s):

Anatolii Serebrov ◽

Vitalii Liamkin ◽

Aleksey Fomin ◽

Valeriy Pusenkov ◽

Konstantin Keshishev ◽

...

Keyword(s):

Cross Section ◽

Superfluid Helium ◽

Thermal Load ◽

Heat Load ◽

Source Parameters ◽

Neutron Guide ◽

Neutron Electric Dipole Moment ◽

Quantum Liquid ◽

Neutron Lifetime ◽

Cold Neutrons

The WWR-M reactor at PNPI is planned to be equipped with a high-flux source for ultracold neutrons (UCNs). The method of UCN production is based on neutron conversion in superfluid helium, exploiting the particular qualities of that quantum liquid. As a result of optimizing the source parameters, we expect a temperature of superfluid helium of 1.2 K and a UCN density of 1.3 × 104 cm−3 in a neutron electric dipole moment (EDM) spectrometer. The expected flux densities of cold neutrons (with wavelengths in the range 2–20 Å) and very cold neutrons (50–100 Å) at the output of a neutron guide with a cross section of 30 × 200 mm2 are 9.7 × 107 cm−2s−1 and 8.3 × 105 cm−2s−1, respectively. The capability of maintaining a temperature of 1.37 K at a thermal load of 60 W was shown experimentally, while the theoretical load is expected to be 37 W. Calculations show that it is possible to decrease the helium temperature down to 1.2 K at similar heat load. The project includes the development of experimental stations at UCN beams, such as for a neutron EDM search, measurements of the neutron lifetime, and for a search for neutron-to-mirror-neutron transitions. In addition, three beams of cold and very cold neutrons are foreseen. At present, the vacuum container of the UCN source has been manufactured and the production of the low-temperature deuterium and helium parts of the source has been started.

Download Full-text

NEUTRON ELECTRIC DIPOLE MOMENT EXPERIMENTS

Modern Physics Letters A ◽

10.1142/s0217732308027771 ◽

2008 ◽

Vol 23 (17n20) ◽

pp. 1397-1408 ◽

Cited By ~ 7

Author(s):

JEN-CHIEH PENG

Keyword(s):

Dipole Moment ◽

Electric Dipole Moment ◽

Superfluid Helium ◽

Electric Dipole ◽

Beyond The Standard Model ◽

Neutron Electric Dipole Moment ◽

Cold Neutrons ◽

The Standard Model ◽

The Status ◽

History Of

The neutron electric dipole moment (EDM) provides unique information on CP violation and physics beyond the Standard Model. We first review the history of experimental searches for neutron electric dipole moment. The status of future neutron EDM experiments, including experiments using ultra-cold neutrons produced in superfluid helium, will then be presented.

Download Full-text

Моделирование источника ультрахолодных нейтронов на реакторе ПИК

Журнал технической физики ◽

10.21883/jtf.2022.02.52025.261-21 ◽

2022 ◽

Vol 92 (2) ◽

pp. 327

Author(s):

А.К. Фомин ◽

А.П. Серебров

Keyword(s):

Monte Carlo ◽

Dipole Moment ◽

Electric Dipole Moment ◽

Computer Model ◽

Electric Dipole ◽

Monte Carlo Model ◽

Ultracold Neutrons ◽

Neutron Guide ◽

Experimental Setup ◽

Guide System

The paper presents the simulation of a complex of reserch with ultracold neutrons at the reactor PIK (Gatchina, Russia). The complex is being built on the basis of a high-intensity source of ultracold neutrons at the channel GEK-4. A Monte Carlo model has been developed, which includes a source, a neutron guide system and an experimental setup for search for the electric dipole moment of a neutron, taking into account their real location in the main hall of the reactor. Using the developed computer model the density of ultracold neutrons in the setup was obtained, which is 200 <sup>-3</sup>. It is 50 times higher than at the source at the Institut Laue-Langevin (Grenoble, France). This density will allow to achieve a sensitivity of measurements in the experiment of 1·10<sup>-27</sup> е·cm/year.

Download Full-text