High-sensitivity measurement of He 3 - He 4 isotopic ratios for ultracold neutron experiments

Authors

H. P. Mumm, National Institute of Standards and Technology
M. G. Huber, National Institute of Standards and Technology
W. Bauder, Pennsylvania State University
N. Abrams, Columbia University
C. M. Deibel, Louisiana State University
C. R. Huffer, NC State University
P. R. Huffman, NC State University
K. W. Schelhammer, NC State University
R. Janssens, Argonne National Laboratory
C. L. Jiang, Argonne National Laboratory
R. H. Scott, Argonne National Laboratory
R. C. Pardo, Argonne National Laboratory
K. E. Rehm, Argonne National Laboratory
R. Vondrasek, Argonne National Laboratory
C. M. Swank, California Institute of Technology
C. M. O'Shaughnessy, The University of North Carolina at Chapel Hill
M. Paul, Hebrew University of Jerusalem
L. Yang, University of Illinois Urbana-Champaign

Document Type

Article

Publication Date

6-13-2016

Abstract

Research efforts ranging from studies of solid helium to searches for a neutron electric dipole moment require isotopically purified helium with a ratio of He3 to He4 at levels below that which can be measured using traditional mass spectroscopy techniques. We demonstrate an approach to such a measurement using accelerator mass spectroscopy, reaching the 10-14 level of sensitivity, several orders of magnitude more sensitive than other techniques. Measurements of He3/He4 in samples relevant to the measurement of the neutron lifetime indicate the need for substantial corrections. We also argue that there is a clear path forward to sensitivity increases of at least another order of magnitude.

Publication Source (Journal or Book title)

Physical Review C

Recommended Citation

Mumm, H., Huber, M., Bauder, W., Abrams, N., Deibel, C., Huffer, C., Huffman, P., Schelhammer, K., Janssens, R., Jiang, C., Scott, R., Pardo, R., Rehm, K., Vondrasek, R., Swank, C., O'Shaughnessy, C., Paul, M., & Yang, L. (2016). High-sensitivity measurement of He 3 - He 4 isotopic ratios for ultracold neutron experiments. Physical Review C, 93 (6) https://doi.org/10.1103/PhysRevC.93.065502