A prestorage method to measure neutron transmission of ultracold neutron guides

Blau, B.; Daum, M.; Fertl, M.; Geltenbort, P.; Göltl, L.; Henneck, R.; Kirch, K.; Knecht, A.; Lauss, B.; Schmidt-Wellenburg, P.; Zsigmond, G.

doi:10.1016/j.nima.2015.10.075

Cited by 16 publications

(19 citation statements)

References 26 publications

(44 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…the cryo-performance of several parts, most importantly the flapper valves (label 8) and UCN guide shutters (label 11). The UCN transport performance of all UCN guides [21] was confirmed prior to their installation. The overall neutron optics performance was later analyzed and understood in terms of a detailed simulation of the entire UCN source [22].…”

Section: Introductionmentioning

confidence: 88%

UCN, the ultracold neutron source -- neutrons for particle physics

Lauss

Blau

2021

SciPost Phys. Proc.

View full text Add to dashboard Cite

Ultracold neutrons provide a unique tool for the study of neutron properties. An overview is given of the ultracold neutron (UCN) source at PSI, which produces the highest UCN intensities to fundamental physics experiments by exploiting the high intensity proton beam in combination with the high UCN yield in solid deuterium at a temperature of 5 K. We briefly list important fundamental physics results based on measurements with neutrons at PSI.

show abstract

Section: Introductionmentioning

confidence: 88%

UCN, the ultracold neutron source -- neutrons for particle physics

Lauss

Blau

2021

SciPost Phys. Proc.

View full text Add to dashboard Cite

show abstract

“…The setup of the experiment can be explained following the cut-view CAD drawing shown in Figure 6 as used for the fall 2020 measurements. UCNs are guided over 2750 mm from the West-1 beamport shutter to the entrance shutter of the storage vessel using nickelmolybdenum (NiMo)-coated glass guides [65,71,72] with an inside diameter of 130 mm. The 1.47 m 3 large UCN storage volume placed inside a large vacuum vessel is made of non-magnetic stainless steel and extends via 200 mm-diameter stainless steel tubes to two shutters.…”

Section: Ultracold Neutron Systemmentioning

confidence: 99%

“…The filling shutter SH1 is a VAT product as described in Ref. [72]. It is coated with diamond-like carbon and is vacuum tight.…”

Section: Ultracold Neutron Systemmentioning

confidence: 99%

Improved Search for Neutron to Mirror-Neutron Oscillations in the Presence of Mirror Magnetic Fields with a Dedicated Apparatus at the PSI UCN Source

Ayres¹,

Berezhiani²,

Biondi³

et al. 2022

Symmetry

Self Cite

View full text Add to dashboard Cite

While the international nEDM collaboration at the Paul Scherrer Institut (PSI) took data in 2017 that covered a considerable fraction of the parameter space of claimed potential signals of hypothetical neutron (n) to mirror-neutron (n′) transitions, it could not test all claimed signal regions at various mirror magnetic fields. Therefore, a new study of n−n′ oscillations using stored ultracold neutrons (UCNs) is underway at PSI, considerably expanding the reach in parameter space of mirror magnetic fields (B′) and oscillation time constants (τnn′). The new apparatus is designed to test for the anomalous loss of stored ultracold neutrons as a function of an applied magnetic field. The experiment is distinguished from its predecessors by its very large storage vessel (1.47 m3), enhancing its statistical sensitivity. In a test experiment in 2020 we have demonstrated the capabilities of our apparatus. However, the full analysis of our recent data is still pending. Based on already demonstrated performance, we will reach sensitivity to oscillation times τnn′/cos(β) well above a hundred seconds, with β being the angle between B′ and the applied magnetic field B. The scan of B will allow the finding or the comprehensive exclusion of potential signals reported in the analysis of previous experiments and suggested to be consistent with neutron to mirror-neutron oscillations.

show abstract

“…UCN which can reach the higher beamport have a minimum energy of 320 neV outside the sD 2 surface, while UCN at West-1 have a minimum energy of 113 neV, similar to the kinetic energy boost by the sD 2 potential [45,46]. Both beamlines are equipped with identically produced UCN guides made from glass tubes with inside coating of nickel-molybdenum [47].…”

Section: Measurements At the Psi Facilitymentioning

confidence: 99%

Solid deuterium surface degradation at ultracold neutron sources

et al. 2018

Self Cite

View full text Add to dashboard Cite

Solid deuterium (sD2) is used as an efficient converter to produce ultracold neutrons (UCN). It is known that the sD2 must be sufficiently cold, of high purity and mostly in its ortho-state in order to guarantee long lifetimes of UCN in the solid from which they are extracted into vacuum. Also the UCN transparency of the bulk sD2 material must be high because crystal inhomogeneities limit the mean free path for elastic scattering and reduce the extraction efficiency. Observations at the UCN sources at Paul Scherrer Institute and at Los Alamos National Laboratory consistently show a decrease of the UCN yield with time of operation after initial preparation or later treatment ("conditioning") of the sD2. We show that, in addition to the quality of the bulk sD2, the quality of its surface is essential. Our observations and simulations support the view that the surface is deteriorating due to a build-up of D2 frost-layers under pulsed operation which leads to strong albedo reflections of UCN and subsequent loss. We report results of UCN yield measurements, temperature and pressure behavior of deuterium during source operation and conditioning, and UCN transport simulations. This, together with optical observations of sD2 frost formation on initially transparent sD2 in offline studies with pulsed heat input at the North Carolina State University UCN source results in a consistent description of the UCN yield decrease.

show abstract

A prestorage method to measure neutron transmission of ultracold neutron guides

Cited by 16 publications

References 26 publications

UCN, the ultracold neutron source -- neutrons for particle physics

UCN, the ultracold neutron source -- neutrons for particle physics

Improved Search for Neutron to Mirror-Neutron Oscillations in the Presence of Mirror Magnetic Fields with a Dedicated Apparatus at the PSI UCN Source

Solid deuterium surface degradation at ultracold neutron sources

Contact Info

Product

Resources

About