Speaker
Description
The A1n, d2n, GEn-II and A_LL experiments at Jefferson lab utilized a high luminosity polarized He3 target for precise measurements at high x and/or Q^2 settings. The target consists of a pumping chamber (where polarization of He3 takes place), a target chamber (where e- beam interacts with the target material) and transfer tubes (which facilitate a convective flow of the polarized material). He3 gas at ~8 atm pressure is filled into the glass cells along with Rb-K alkali mixture and narrow band diode lasers are used for polarizing the He3 using a SEOP (Spin Exchange Optical Pumping) technique. The target system used in the experiment includes Helmholtz coils to create a holding field that determines the direction of polarization for the He3 nuclei. Two polarimetry techniques are used to determine the absolute (EPR) and relative (EPR) polarization during production running. Physics goals of these experiments and the overall target performance will be briefly discussed in this talk.
