%0 Journal Article
%A Parnell, S.R.
%A Babcock, E.
%A Nüninghof, K.
%A Skoda, M. W. A.
%A Boag, S.
%A Masalovich, S.
%A Chen, W.C.
%A Georgii, R.
%A Wild, J.M.
%A Frost, C.D.
%T Study of spin-exchange optically pumped 3He cells with high polarisation and long lifetimes
%J Nuclear instruments & methods in physics research / A
%V 598
%@ 0168-9002
%C Amsterdam
%I North-Holland Publ. Co.
%M PreJuSER-2019
%P 774 - 778
%D 2009
%Z The authors would like to thank Dr. T. Gentile for loan of the cell Lion and feedback on this work. Dr. A. loffe for useful discussions and O. Lykhvar for technical support during our experiments at FRM-2. This research project has been supported by EPSRC [EP/D070252/1], STFC [CC/DO00130/1] and the European Commission under the 6<SUP>th</SUP> Framework Programme through the Key Action: Strengthening the European Research Area, Research Infrastructures. Contract no: RII3-CT-2003-505925.
%X We present a detailed investigation in to He-3 neutron spin filter cells polarised by spin exchange optical pumping (SEOP). We include measurements of the absolute He-3 polarisation using neutron transmission and characterisation of both the X-factor and He-3 relaxation times (T-1) for a number of cells. For one cell we calculated a Maximum He-3 polarisation of 79% with a T, of 633 h. The measured X-factor of this cell, X = 0.17 +/- 0.01, is low. For all cells polarisations of > 71% are observed. In addition we present He-3 relaxation data for a new design of magneto-static cavity with a field of high homogeneity Delta B/B-0 approximate to 3.5 x 10(-4) cm(-1). This compact device provides a magnetic field in an orientation suitable for in situ optical pumping that minimises the field inhomogeneity contribution to the T, to 930h in a 1 bar cell, the longest reported on beam thus far. The results suggest that high He-3 polarisation with long relaxation times can now be routinely obtained with SEOP, enabling time independent incident beam polarisation to be easily implemented across many different neutron Scattering instruments. (c) 2008 Elsevier B.V. All rights reserved.
%K J (WoSType)
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000262825500015
%R 10.1016/j.nima.2008.10.009
%U https://juser.fz-juelich.de/record/2019