scholarly journals The search for the neutron electric dipole moment at PSI

2021 ◽  
Author(s):  
Guillaume Pignol ◽  
Philipp Schmidt-Wellenburg
Keyword(s):  
Dipole Moment ◽  
Electric Dipole Moment ◽  
Electric Dipole ◽  
New Physics ◽  
Permanent Electric Dipole Moment ◽  
Order Of Magnitude ◽  
Under Construction ◽  
Paul Scherrer ◽  
The Universe ◽  
Shed Light

The existence of a nonzero permanent electric dipole moment (EDM) of the neutron would reveal a new source of CP violation and shed light on the origin of the matter–antimatter asymmetry of the Universe. The sensitivity of current experiments using stored ultracold neutrons (UCN) probe new physics beyond the TeV scale. Using the UCN source at the Paul Scherrer Institut, the nEDM collaboration has performed the most sensitive measurement of the neutron EDM to date, still compatible with zero (|d_n|<1.8\times 10^{-26} \, e {cm}|dn|<1.8×10−26ecm, C.L.,90%). A new experiment designed to improve the sensitivity by an order of magnitude, n2EDM, is currently under construction.

scholarly journals The design of the n2EDM experiment

2021 ◽  
Vol 81 (6) ◽  
Author(s):  
N. J. Ayres ◽  
G. Ban ◽  
L. Bienstman ◽  
G. Bison ◽  
K. Bodek ◽  
...  
Keyword(s):  
Dipole Moment ◽  
Experimental Method ◽  
Neutron Source ◽  
High Precision ◽  
Electric Dipole Moment ◽  
Electric Dipole ◽  
Technical Design ◽  
Order Of Magnitude ◽  
Under Construction ◽  
Paul Scherrer

AbstractWe present the design of a next-generation experiment, n2EDM, currently under construction at the ultracold neutron source at the Paul Scherrer Institute (PSI) with the aim of carrying out a high-precision search for an electric dipole moment of the neutron. The project builds on experience gained with the previous apparatus operated at PSI until 2017, and is expected to deliver an order of magnitude better sensitivity with provision for further substantial improvements. An overview is of the experimental method and setup is given, the sensitivity requirements for the apparatus are derived, and its technical design is described.

scholarly journals The PanEDM neutron electric dipole moment experiment at the ILL

2019 ◽  
Vol 219 ◽  
pp. 02006 ◽  
Author(s):  
David Wurm ◽  
Douglas H. Beck ◽  
Tim Chupp ◽  
Skyler Degenkolb ◽  
Katharina Fierlinger ◽  
...  
Keyword(s):  
Dipole Moment ◽  
Electric Dipole Moment ◽  
Electric Dipole ◽  
Damping Factor ◽  
First Order ◽  
Permanent Electric Dipole Moment ◽  
Field Homogeneity ◽  
Order Of Magnitude ◽  
Magnetic Stability ◽  
Magnitude Improvement

The neutron's permanent electric dipole moment dn is constrained to below 3 × 10−26e cm (90% C.L.) [1, 2], by experiments using ultracold neutrons (UCN). We plan to improve this limit by an order of magnitude or more with PanEDM, the first experiment exploiting the ILL's new UCN source SuperSUN. SuperSUN is expected to provide a high density of UCN with energies below 80 neV, implying extended statistical reach with respect to existing sources, for experiments that rely on long storage or spin-precession times. Systematic errors in PanEDM are strongly suppressed by passive magnetic shielding, with magnetic field and gradient drifts at the single fT level. A holding-field homogeneity on the order of 10−4 is achieved in low residual fields, via a high static damping factor and built-in coil system. No comagnetometer is needed for the first order-of-magnitude improvement in dn, thanks to high magnetic stability and an assortment of sensors outside the UCN storage volumes. PanEDM will be commissioned and upgraded in parallel with SuperSUN, to take full advantage of the source's output in each phase. Commissioning is ongoing in 2019, and a new limit in the mid 10−27e cm range should be possible with two full reactor cycles of data in the commissioned apparatus.

scholarly journals EDM: Neutron electric dipole moment measurement

2016 ◽  
Vol 1 ◽  
Author(s):  
Peter Fierlinger
Keyword(s):  
Dipole Moment ◽  
Electric Dipole Moment ◽  
Electric Dipole ◽  
Particle Physics ◽  
New Physics ◽  
Beyond The Standard Model ◽  
Fundamental Physics ◽  
Clear Sign ◽  
High Measurement ◽  
The Universe

An electric dipole moment (EDM) of the neutron would be a clear sign of new physics beyond the standard model of particle physics. The search for this phenomenon is considered one of the most important experiments in fundamental physics and could provide key information on the excess of matter versus antimatter in the universe. With high measurement precision, this experiment aims to ultimately achieve a sensitivity of 10-28 ecm, a 100-fold improvement in the sensitivity compared to the state-of-the-art. The EDM instrument is operated by an international collaboration based at the Technische Universität München.

The permanent electric dipole moment of CaOH

1990 ◽  
Vol 93 (6) ◽  
pp. 4179-4186 ◽  
Author(s):  
Charles W. Bauschlicher ◽  
Stephen R. Langhoff ◽  
Timothy C. Steimle ◽  
Jeffrey E. Shirley
Keyword(s):  
Dipole Moment ◽  
Electric Dipole Moment ◽  
Electric Dipole ◽  
Permanent Electric Dipole Moment

Interference effects in the spectrum of HD: I. The fundamental band of pure HD

1983 ◽  
Vol 61 (12) ◽  
pp. 1648-1654 ◽  
Author(s):  
N. H. Rich ◽  
A. R. W. McKellar
Keyword(s):  
Absorption Spectrum ◽  
Dipole Moment ◽  
Phase Shift ◽  
Electric Dipole Moment ◽  
Electric Dipole ◽  
High Density ◽  
Line Profiles ◽  
Interference Effects ◽  
Permanent Electric Dipole Moment ◽  
Precise Interpretation

The absorption spectrum of the ν = 1 ← 0 band of HD has been investigated at a temperature of 77 K and for densities in the range of 15 to 140 amagat. The band consists of two components: a broad collision-induced quasi continuum arising from dipoles induced during molecular collisions; and a dipole-allowed part arising from the small permanent electric dipole moment of the free HD molecule. The interference effects which occur between these two components were studied for the dipole-allowed R1(0) and R1(1) transitions. These transitions exhibited increasingly large asymmetries and changes in intensity at high density, but their behaviours were quite different from each other. The shape of each transition could be well represented by a series of Fano line profiles, and the evolution of shape and intensity with density could be accounted for by the formulation of Herman, Tipping, and Poll. However, the precise interpretation of the phase shift parameters arising in the theory is not clear.

Sign in / Sign up

Export Citation Format

Share Document