[b1_ana] LiD, Tensor Workshop Discussions, and Moving Forward

[O. A. Rondon]

Hi,

To have more quantitative information about the behavior of LiD's
polarization at high field, I digitized the data plotted on Fig. 5
of the 1999-2000 Research Run tech. note
http://userweb.jlab.org/~slifer/b1/papers/B28resnote.pdf

so I could fit it and extrapolate to later times.

Fits of the form P0*log(c*t) work very well. I fitted the data for t>~85
min, which corresponds to the time after a significant change in trend
probably due to a microwave frequency change, and for t>~295 min, when
another change in trend is visible.

Both fits agree quite well with the data. The later time fit
extrapolates to a bit lower P(t) than the earlier time fit, as it can be
expected. The results are here
https://twist.phys.virginia.edu/~or/b1/lidvst7t.pdf

The extrapolation to 11 h shows that the polarization would be about
37%. This is without beam irradiation damage, which stops further
polarization increase above P = ~ -31% after a dose of about 5E15
e/cm^2, at 5T and 1K, see Fig. 10 in
A Study of lithium deuteride as a material for a polarized target
http://inspirehep.net/record/474569

The maximum LiD polarization achievable with high field under an
electron beam (1K spin bath temp.) would seem to be < 45%.

Cheers,

Oscar