1. 2001/9/20Laser Driven Target http://ldt.mit.edu 1 Laser Driven Target at MIT Chris Crawford, Ben Clasie, Jason Seely, Dipangkar Dutta, Haiyan Gao Introduction Optical pumping Spincell optimization Components of the LDT Atomic Fraction Results Preliminary Polarization Future Work

2. 2001/9/20Laser Driven Target http://ldt.mit.edu 2 Atomic Beam Source Well established technology Can create pure spin states 8 x 10 16 atoms/s 84% atomic fraction 80% polarization Laser Driven Target Compact design Active pumping—higher flux 2 x 10 18 atoms/s 60% atomic fraction 50% polarization Overview

3. 2001/9/20Laser Driven Target http://ldt.mit.edu 3 Optical Pumping At spin temperature equilibrium, the population of each spin state n(m F ) is controlled by the Boltzmann equation.

4. 2001/9/20Laser Driven Target http://ldt.mit.edu 4 Spincell Optimization Developed a code to simulate recombination and depolarization One must minimize the Surface Area / Volume ratio, and the length of the transport tube Dimensions: 2” diameter spherical spincell with 5 cm neck

5. 2001/9/20Laser Driven Target http://ldt.mit.edu 5 Target Chamber

6. 2001/9/20Laser Driven Target http://ldt.mit.edu 6 Polarimeter

7. 2001/9/20Laser Driven Target http://ldt.mit.edu 7 Sextupole Magnet

8. 2001/9/20Laser Driven Target http://ldt.mit.edu 8 QMA Detector

9. 2001/9/20Laser Driven Target http://ldt.mit.edu 9 Dissociator Trials

10. 2001/9/20Laser Driven Target http://ldt.mit.edu 10 Atomic Fraction

11. 2001/9/20Laser Driven Target http://ldt.mit.edu 11 Preliminary Polarization Laser transmission QMA mass 1 signal polarization: 20% (+ helicity) and 23% (- helicity) polarization preserving mirrors only 87% efficient

12. 2001/9/20Laser Driven Target http://ldt.mit.edu 12 Future Work Redo polarization tests with correct mirrors. Fine-tune operational parameters. Investigate the quality of the spincell coating. Investigate performance of sextupole filter. Run tests with deuterium. Redesign target for operation at BLAST.