Gravitational depolarization of ultracold neutrons: Comparison with data

We compare the expected effects of so-called gravitationally enhanced depolarization of ultracold neutrons to measurements carried out in a spin-precession chamber exposed to a variety of vertical magnetic-field gradients. In particular, we have investigated the dependence upon these field gradients of spin-depolarization rates and also of shifts in the measured neutron Larmor precession frequency. We find excellent qualitative agreement, with gravitationally enhanced depolarization accounting for several previously unexplained features in the data.

[1]  S. N. Ivanov,et al.  A measurement of the neutron to 199Hg magnetic moment ratio , 2014, 1410.8259.

[2]  White,et al.  Spin relaxation in gases due to inhomogeneous static and oscillating magnetic fields. , 1988, Physical review. A, General physics.

[3]  L. Trahms,et al.  The search for the neutron electric dipole moment at the Paul Scherrer Institute , 2011 .

[4]  Mcgregor.  Transverse relaxation of spin-polarized 3He gas due to a magnetic field gradient. , 1990, Physical review. A, Atomic, molecular, and optical physics.

[5]  S. Roccia,et al.  Electric dipole moment searches: reexamination of frequency shifts for particles in traps , 2012, 1201.0699.

[6]  M. G. RUSBRIDGE,et al.  Kinetic Theory , 1969, Nature.

[7]  Detailed discussion of a linear electric field frequency shift induced in confined gases by a magnetic field gradient: Implications for neutron electric-dipole-moment experiments , 2004, nucl-ex/0407005.

[8]  A. Hofer,et al.  Laser-driven Cs magnetometer arrays for magnetic field measurement and control , 2009 .

[9]  S. N. Ivanov,et al.  Improved experimental limit on the electric dipole moment of the neutron. , 2006 .

[10]  S. N. Ivanov,et al.  Apparatus for measurement of the electric dipole moment of the neutron using a cohabiting atomic-mercury magnetometer , 2013, 1305.7336.

[11]  W. Griffith,et al.  Observation of Gravitationally Induced Vertical Striation of Polarized Ultracold Neutrons by Spin-Echo Spectroscopy. , 2015, Physical review letters.

[12]  R. Franke,et al.  MC calculations for the nEDM experiment systematics , 2011 .

[13]  P. Iaydjiev,et al.  Performance of an atomic mercury magnetometer in the neutron EDM experiment , 1998 .

[14]  N. Devenish,et al.  Gravitationally enhanced depolarization of ultracold neutrons in magnetic-field gradients , 2013, 1306.1252.

[15]  Aaas News,et al.  Book Reviews , 1893, Buffalo Medical and Surgical Journal.

[16]  B. Lauss,et al.  Ultracold Neutron Production at the Second Spallation Target of the Paul Scherrer Institute , 2014 .

[17]  K. Perez.  Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment , 2014 .

[18]  G. Bison,et al.  Dynamic stabilization of the magnetic field surrounding the neutron electric dipole moment spectrometer at the Paul Scherrer Institute , 2014, 1408.6752.

[19]  S. Lamoreaux,et al.  Neutron electric-dipole moment, ultracold neutrons and polarized 3He , 1994 .

[20]  Reexamination of relaxation of spins due to a magnetic field gradient: Identity of the Redfield and Torrey theories , 2010, 1010.6266.

[21]  D. Broadhurst.  THE NEUTRON ELECTRIC DIPOLE MOMENT ? , 1971 .

[22]  Miss A.O. Penney.  (b) , 1974, The New Yale Book of Quotations.

[23]  G. Bison,et al.  A device for simultaneous spin analysis of ultracold neutrons , 2015, The European Physical Journal A.

[24]  Cates,et al.  Relaxation of spins due to field inhomogeneities in gaseous samples at low magnetic fields and low pressures. , 1988, Physical review. A, General physics.

[25]  John B. Shoven,et al.  I , Edinburgh Medical and Surgical Journal.

[26]  J. Richardson,et al.  Improved experimental limit on the electric dipole moment of the neutron. , 2006, Physical review letters.

[27]  G. K. Walters,et al.  NUCLEAR SPIN-LATTICE RELAXATION IN THE PRESENCE OF MAGNETIC-FIELD GRADIENTS , 1965 .

[28]  S. N. Ivanov,et al.  Geometric-phase-induced false electric dipole moment signals for particles in traps , 2004, physics/0510134.

[29]  K. Smith.  Ultra-cold neutrons , 1980 .

[30]  Daniel Kleppner,et al.  THEORY OF THE HYDROGEN MASER , 1962 .