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Optical magnetometry for a new neutron EDM experiment

English title Optical magnetometry for a new neutron EDM experiment
Applicant Weis Antoine
Number 140421
Funding scheme Project funding
Research institution Département de Physique Université de Fribourg
Institution of higher education University of Fribourg - FR
Main discipline Other disciplines of Physics
Start/End 01.04.2012 - 31.03.2015
Approved amount 538'438.00
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Keywords (11)

ultra cold neutrons; P violation; electric dipole moment; magnetic resonance; Ramsey spectroscopy; CP violation; magnetic fields; 3He magnetometry; T violation; atomic magnetometry; violation of discrete symmetry

Lay Summary (English)

Lead
Lay summary
We are working in an international collaboration on an experiment aiming at an improved sensitivity to the neutron electric dipole moment (nEDM). The EDM for an elementary particle is forbidden by both Parity and Time reversal symmetries. The starting point is the reasonable presumption that an improvement of the experimental sensitivity to below a level of 10e-27 e cm can be achieved using in-vacuum techniques: note that the in-vacuum technique was used by the Sussex--RAL--ILL collaboration to set the present limit of dn < 63x10e-27 e cm, and that the measurement is claimed to be at its statistical limit. A long-term ultimate sensitivity in the 10e-28 e cm region is interesting since several extensions to the Standard Model (Left--Right symmetric models, and Supersymmetry) predict a value for the nEDM in that range. Central to this work is the measurement and control of the magnetic field used to precess the magnetic moments of an ensemble of neutrons. The Ramsey method of separated oscillatory fields is used to measure the perturbation of the spin precession in a magnetic field caused by an additional electric field. The measurement then compares aligned fields with anti-aligned fields to isolate the electric field effect. The stability of the magnetic field between the two measurements is paramount to the success and sensitivity of the method. The Fribourg atomic physics group (FRAP) will undertake the task of maintaining the stability of the magnetic field to the precision levels necessary for the experiment. Our approach will be to place an array of laser--pumped Cs magnetometers into the vacuum apparatus and use the resulting measurements to both actively stabilize the magnetic field, and to correct the Ramsey oscillating--field phase for rapid magnetic field fluctuations. The magnetometry data collected during the operation of the existing nEDM apparatus will be used to optimize the design of a future apparatus for the conditions at PSI. The neutron data collected at the same time should already serve to increase the sensitivity to any nEDM, with the immediate short term goal of dn < few x 10e-26 e cm being comparable to the existing world limit.
Direct link to Lay Summary Last update: 21.02.2013

Responsible applicant and co-applicants

Employees

Publications

Publication
Constraining interactions mediated by axion-like particles with ultracold neutrons
Afach S., Ban G., Bison G., Bodek K., Burghoff M., Daum M., Fertl M., Franke B., Grujić Z.D., Hélaine V., Kasprzak M., Kermaïdic Y., Kirch K., Knowles P., Koch H.-C., Komposch S., Kozela A., Krempel J., Lauss B., Lefort T., Lemière Y., Mtchedlishvili A., Naviliat-Cuncic O., Piegsa F.M., Pignol G. (2015), Constraining interactions mediated by axion-like particles with ultracold neutrons, in Physics Letters B , 745(0), 58-63.
A measurement of the neutron to 199Hg magnetic moment ratio
Afach S., Baker Chuck A H, Ban Gilles, Bison Georg, Bodek Kazimierz, Burghoff Martin, Chowdhuri Zema, Daum Manfred, Fertl M., Franke B., Geltenbort Peter V., Green Katie L., Van Der Grinten Maurits G D, Grujić Zoran D., Harris Philip G., Heil Werner, Hélaine V., Henneck Reinhold, Horras M., Iaydjiev P. S., Ivanov Sergey N., Kasprzak Mirosaw M., Kermaïdic Y., Kirch Klaus, Knecht Andreas (2014), A measurement of the neutron to 199Hg magnetic moment ratio, in Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, 739, 128-132.
Development of a 3He magnetometer for a neutron electric dipole moment experiment
Kraft Andreas, Koch Hans-Christian, Daum Manfred, Heil Werner, Lauer Thorsten, Neumann Daniel, Pazgalev Anatoly, Sobolev Yuri, Weis Antoine (2014), Development of a 3He magnetometer for a neutron electric dipole moment experiment, in EPJ Techniques and Instrumentation, 1(1), x.
Dynamic stabilization of the magnetic field surrounding the neutron electric dipole moment spectrometer at the Paul Scherrer Institute
Afach S., Bison G., Bodek K., Burri F., Chowdhuri Z., Daum M., Fertl M., Franke B., Grujic Z., Hélaine V., Henneck R., Kasprzak M., Kirch K., Koch H.-C., Kozela A., Krempel J., Lauss B., Lefort T., Lemière Y., Meier M., Naviliat-Cuncic O., Piegsa F. M., Pignol G., Plonka-Spehr C., Prashanth P. N. (2014), Dynamic stabilization of the magnetic field surrounding the neutron electric dipole moment spectrometer at the Paul Scherrer Institute, in Journal of Applied Physics, 116(8), 084510.
Atomic magnetic resonance induced by amplitude-, frequency-, or polarization-modulated light
Grujic Z. D., Weis A (2013), Atomic magnetic resonance induced by amplitude-, frequency-, or polarization-modulated light, in Phys. Rev. A, 88(1), 012508.
A sensitive and accurate atomic magnetometer based on free spin precession
Grujić Zoran D., Koss Peter A., Bison Georg, Weis Antoine, A sensitive and accurate atomic magnetometer based on free spin precession, in The European Physical Journal D.

Collaboration

Group / person Country
Types of collaboration
Institut fuer Physik, Mainz Germany (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
- Research Infrastructure
- Exchange of personnel
LPC-Caen (IN2P3/CNRS/ENSICaen) France (Europe)
- Research Infrastructure
Department of Physics and Astronomy, University of Sussex Great Britain and Northern Ireland (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Research Infrastructure
University of Kentucky Lexington, Department of Physics and Astronomy, Kentucky United States of America (North America)
- Research Infrastructure
Institute for Particle Physics, ETH, Zurich Switzerland (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Research Infrastructure
LPSC Grenoble France (Europe)
- Research Infrastructure
PTB Berlin Germany (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Research Infrastructure
Universitaetsklinikum Jena, Germany Germany (Europe)
- in-depth/constructive exchanges on approaches, methods or results
Paul Scherrer Institute Switzerland (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
- Research Infrastructure
- Exchange of personnel
Centre de Sciences Nucléaires et de Sciences de la Matière - CSNSM, Université Paris-Sud France (Europe)
- Research Infrastructure
Jagiellonian University, Cracow, Institute of Physics Poland (Europe)
- Research Infrastructure
Instituut voor Kern- en Stralingsfysica, Katholieke Universiteit Leuven Belgium (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Research Infrastructure

Scientific events

Active participation

Title Type of contribution Title of article or contribution Date Place Persons involved
8. Radionica fotonike Talk given at a conference Free spin precession magnetometer for fundamental research 08.03.2015 Kopaonik, Serbien Weis Antoine;
Challenges of the world-wide experimental search for the electric dipole moment of the neutron Poster A combined 3He/Cs magnetometer for absolute measurements of magnetic fields 02.11.2014 Ascona, Switzerland Weis Antoine; Koch Hans-Christian; Kasprzak Malgorzata; Knowles Paul;
Challenges of the world-wide experimental search for the electric dipole moment of the neutron Poster Cs magnetometer array in the nEDM experiment 02.11.2014 Ascona, Switzerland Weis Antoine; Kasprzak Malgorzata;
Particles and Nuclei International Conference 2014 Talk given at a conference Experimental search for an electric dipole moment of the neutron 25.08.2014 Hamburg, Germany Kasprzak Malgorzata;
SPS Annual Meeting 2014 Talk given at a conference Atomic magnetometer array in the nEDM experiment 30.06.2014 Fribourg, Switzerland Kasprzak Malgorzata;
SPS annual meeting 2014 Talk given at a conference A 3He/Cs agnetometer for absolute measurements of magnetic fields 30.06.2014 Fribourg, Switzerland Kasprzak Malgorzata; Weis Antoine;
DPG Frühjahrstagung, Sektion AMOP Talk given at a conference An absolute, high-precision 3He / Cs combined magnetometer 17.03.2014 Huboldt-Universität zu Berlin, Germany Koch Hans-Christian; Weis Antoine;
7. Radionica fotonike Talk given at a conference Precizna magnetometrija, novi rezultati grupe za atomsku fiziku Departmana za fiziku u Friburgu 10.03.2014 Kopaonik, Serbien Weis Antoine;
Physics of fundamental Symmetries and Interactions - PSI2013 Poster Accuracy before sensitivity: Magnetically-silent vector magnetometer a new tool for nEDM search 08.09.2013 PSI Villigen, Switzerland Weis Antoine; Knowles Paul;
Physics of fundamental Symmetries and Interactions - PSI2013 Poster Atomic cesium magnetometers in the search for neutron EDM 08.09.2013 PSI Villigen, Switzerland Knowles Paul; Kasprzak Malgorzata; Macchione Catherine; Weis Antoine;
Physics of fundamental Symmetries and Interactions - PSI2013 Poster An absolute, high-precision 3He / Cs combined magnetometer 08.09.2013 Paul Scherrer Institute, Villigen, Switzerland Weis Antoine; Koch Hans-Christian;
Photonica'13 Poster Algebraic model and experimental verification of magnetic resonance induced either by amplitude-modulated or polarization-modulated light 26.08.2013 University of Belgrade, Serbien Knowles Paul; Weis Antoine;
MPLP'2013 - 6th International Symposium on Modern Problems of Laser Physics Individual talk New trends in atomic magnetometry and its applications 25.08.2013 Novosibirsk, Russia Weis Antoine;
IFCS / EFTF 2013 Individual talk Atomic Magnetometry for Biomedical and Fundamental Research 21.07.2013 Prague, Czech Republic Weis Antoine;
Physikalisches Kolloquium Individual talk Atomic magnetometry for biomedical and fundamental research 02.07.2013 Uni Stuttgart, Germany Weis Antoine;
ECAMP-11 Poster Magnetically-silent vector magnetometry based on the free induction decay of atomic spin polarization 26.06.2013 Aarhus, Denmark Knowles Paul; Weis Antoine;
ECAMP-11 Individual talk Atomic magnetometry for biomedical and fundamental research 24.06.2013 Aarhus, Denmark Weis Antoine;
V-th International Conference of the Young Scientists - Plovdiv 2013 Poster An absolute, high precision 3He-Cs magnetometer 13.06.2013 Plovdiv, Bulgaria Weis Antoine; Koch Hans-Christian;
EGAS 44 Poster Algebraic model and experimental verification of magnetic resonance induced by amplitude-modulated light 09.07.2012 University of Gothenburg, Sweden Knowles Paul; Kasprzak Malgorzata; Koch Hans-Christian; Weis Antoine;
EGAS--44 Poster Optical cesium magnetometers for high precision magnetic field measurements (PO-021) 09.07.2012 University of Gothenburg, Sweden Knowles Paul; Koch Hans-Christian; Kasprzak Malgorzata; Weis Antoine;
SPS Annual Meeting 2012 Poster Optical cesium magnetometers for the PSI neutron electric dipole moment experiment 21.06.2012 Zurich, Switzerland Kasprzak Malgorzata;


Awards

Title Year
Honorary Diploma for the best presentation of a paper for poster presentation "An absolute, high precision $^3$He-Cs magnetometer" by H.-C. Koch at V-th International Conference of the Young Scientists, Plovdiv, Bulgaria, 13-16 June, 2013 2013

Associated projects

Number Title Start Funding scheme
149211 Measurement of the neutron electric dipole moment 01.11.2013 Project funding
131926 A push-pull magnetometer with an internal microwave frequency reference 01.01.2011 Ambizione
162574 Measurement of the neutron electric dipole moment 01.11.2015 Project funding
130480 Optical magnetometry for a new neutron EDM experiment 01.04.2010 Project funding
172626 Highly accurate vector gradiometers for a next-generation neutron EDM experiment 01.08.2017 Project funding
172639 Precision Physics with Muons and Ultracold Neutrons 01.05.2017 Project funding
130414 Spatially resolved magneto-relaxation of in-vitro magnetic nanoparticles using atomic magnetometry 01.09.2010 Sinergia

Abstract

We are working in an international collaboration on an experiment aiming at an improved sensitivity to the neutron electric dipole moment (nEDM). The collaboration has existed for several years, and this request is the fourth continuation we are making for our participation in this project.The collaboration will improve the experimental sensitivity to a level below 10^-27 e·cm using ultra cold neutrons (UCN) stored in vacuum. We note that the in-vacuum technique was used by the Sussex-RAL-ILL collaboration to set the present upper limit of d_n to <29×10^-27 e·cm, a value that is claimed to be at its statistical limit [C. A. Baker et al., Phys. Rev. Lett. 97, 131801 (2006)]. The apparatus used in that measure (referred to as "OILL" herein) has been recovered and installed at PSI by the collaboration and will be used in the first phase of the PSI nEDM measurements. A long-term ultimate sensitivity of 10^-28 e·cm is interesting since several extensions to the Standard Model (Left-Right symmetric models, and Supersymmetry) predict a value for the P- and -violating nEDM in that range.Central to this work is the measurement and control of -with particular importance on systematic effects related to- the magnetic field used to precess the magnetic moments of an ensemble of polarized neutrons. The Ramsey method of separated oscillatory fields is used to measure the spin precession of neutrons subjected to a static magnetic field and perturbed by an additional static electric field. The comparison of measurements with parallel fields to those with antiparallel fields isolates any electric field dependence of the precession frequency. The magnetic field stability between two measurements is critical to the sensitivity of the method.The Fribourg atomic physics group (FRAP) works on the task of measuring and stabilizing the magnetic field and its first order gradient to the precision levels necessary for the experiment. Our approach relies on the installation of an array of (several dozen) laser-pumped Cs magnetometer modules inside the vacuum apparatus and use the resulting measurements to both actively stabilize the magnetic field, and to correct the Ramsey oscillating-field phase for rapid magnetic field fluctuations. The magnetometry data collected during the operation of the existing nEDM apparatus will be used to optimize the design of a future nEDM apparatus at the new ultra-cold neutron (UCN) source at PSI. The neutron data collected at the same time should already serve to increase the statistical sensitivity to any nEDM, with the immediate short term goal of d_n
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