Tensor Target Polarization at TRIUMF Erich Vogt TRIUMF

Tensor Target Polarization at TRIUMF Erich Vogt TRIUMF director 1981 -1994 G. Smith, JLab • 1929 -2014 G. Smith, March 2014 Tensor Polarized Targets at TRIUMF 1

Nomenclature • G. Smith, March 2014 Tensor Polarized Targets at TRIUMF 2

Some Basic Formulas • G. Smith, March 2014 Tensor Polarized Targets at TRIUMF 3

Plots • Dilution refrigerator 3 He refrigerator Not much to work with! G. Smith, March 2014 Tensor Polarized Targets at TRIUMF 4

SIN LAMPF G. Smith, March 2014 Tensor Polarized Targets at TRIUMF 5

How to resolve this? • G. Smith, March 2014 Tensor Polarized Targets at TRIUMF 6

G. Smith, March 2014 Tensor Polarized Targets at TRIUMF 7

Full calc No P 11 abs T 20 First Results SIN t 20 LAMPF t 20 TRIUMF t 20 TRIUMF T 20 G. Smith, March 2014 Tensor Polarized Targets at TRIUMF 8

Conditions: • G. Smith, March 2014 Tensor Polarized Targets at TRIUMF 9

pzz is abstract. Can we trust it? • Area & R techniques rely on assumptions: – D quadrupole moment contribution negligible • 20 k. Hz vs 16 MHz @ 2. 5 T – Boltzmann dist. (equal spin temps) • Kiss that goodbye with RF burning – pzz deduced from msrd pz – pzz is bloody small… – NMR system linear over a wide range • In gain (~3 orders of magnitude) • In frequency too (16. 6 ± 0. 3 MHz @ 2. 5 T) G. Smith, March 2014 Tensor Polarized Targets at TRIUMF 10

Novel DIRECT msr of pzz • G. Smith, March 2014 Tensor Polarized Targets at TRIUMF 11

pzz Experiment Msrd Ayy in pp πd Our PSA Flinders PSA beam Fadeev C 4 D 9 OD BKG: QF abs on 12 C Took T 20= -1. 28 ± 0. 03 after accounting for ± 2. 5º angular acceptance G. Smith, March 2014 Tensor Polarized Targets at TRIUMF Since no C 4 H 9 OH abs on H, this is a (bkg) perfect bkg tgt! foreground minus bkg 12

Benchmarking pzz Results • Analyzed πd 2 p data using: pzz – TOF: pzz = 0. 098 ± 0. 024 – Coplanarity: pzz = 0. 100 ± 0. 022 • Using NMR techniques: – NMR Areas: pzz = 0. 083 ± 0. 008 – NMR peak ratios: pzz = 0. 095 ± 0. 008 • RF pedestal burning msrd in frozen spin mode (no μw) over 18 h after burning. NMR pzz unknown: – TOF: pzz = 0. 10 ± 0. 017 – Coplanarity: pzz = 0. 11 ± 0. 018 – Consistent with unburned • Either no enhancement, or relaxation times too short G. Smith, March 2014 Tensor Polarized Targets at TRIUMF ok ? ? ? 13

More on Burning • Saw no effect – – Avg of πd 2 p burned πd 2 p unburned Within our uncertainties Also none from holding field But pzz was very small Hazy on what NMR predicted burned pzz was NMR 1. 25 T 2. 5 T burned • I think it was Δpzz ~ 0. 05 (see TRI-PP-86 -027 by Delheij, Healey & Wait) – Really no effect? • Msrd burned/unburned = 1. 08 ± 0. 30 • A larger ratio if comparing burned to NMR… grasping at straws though – After burning, msrd average polarization over an 18 h period • Did not investigate shorter time periods • Was frozen spin the problem? – May have had better rslts with MUCH higher B (longer relaxation times) • Need to know pzz during the entire physics msrmnt – Problematic if burned pzz(time) is hard to msr G. Smith, March 2014 Tensor Polarized Targets at TRIUMF 14

TRIUMF Tgt Grp G. Smith, March 2014 Tensor Polarized Targets at TRIUMF 15

Next: T 21 G. Smith, March 2014 Tensor Polarized Targets at TRIUMF 16

How to get at T 21? • G. Smith, March 2014 Tensor Polarized Targets at TRIUMF 17

Choice of Euler Angles Determines the Observables • G. Smith, March 2014 Tensor Polarized Targets at TRIUMF 18

pzz=0. 17 pz=0. 47 TE • C 4 D 9 OD G. Smith, March 2014 Small at back angles C 4 H 9 OH Tensor Polarized Targets at TRIUMF 19

More on T 20 & T 21 pzz 0. 10 up to 0. 17 pz=0. 47 G. Smith, March 2014 Tensor Polarized Targets at TRIUMF 20

Some Results Full 3 body (Flinders) Same, but w/o P 11 Better without the P 11 ! G. Smith, March 2014 Tensor Polarized Targets at TRIUMF 21

The P 11 Phase Shift • NN – πNN system: hard to couple to 2 body cuz π can absorb on one N and be emitted by the other. – Soln: treat abs. via the P 11 πN interaction • 3 -body calculations sensitive to cancellation of the pole (true π absorption) & non-pole (multiple scattering w/o absorption) in the P 11 πN phase shift. – Problem: cacl’s w/o the P 11 generally compare better to data! – Soln (Jennings, PLB 205, 187 (1988): Pole term Pauli blocked. Missing diagrams (different time ordering) cancel ones responsible for the Pauli blocking & improves agreement! G. Smith, March 2014 cancels 1 b & 1 c Tensor Polarized Targets at TRIUMF missing 22

Back to SIN/PSI • Propandiol: C 3 D 6(OD)2 & C 3 D 6(OH)2 92% deuterated, doped with Cr. V – 1 mm beads in a 0. 1 mm thick 5 x 18 mm 3 brass cell – 4 m. W cooling power – 50 m. K dilution fridge – Up to pz=-0. 48 (pzz=0. 18) after 12 h G. Smith, March 2014 Tensor Polarized Targets at TRIUMF 150 h @ 0. 83 T 23

Extraction Method 2: Fitting • T 20 G. Smith, March 2014 Tensor Polarized Targets at TRIUMF 24

Extraction Method 3: Matrices Row averages • Column averages Diagonal matrix elements & result = weighted avg 294 Me. V, θπ=151° G. Smith, March 2014 Tensor Polarized Targets at TRIUMF 25

+41. 7% 134º 76º -48. 2% • 400 h @ 2. 5 T G. Smith, March 2014 Tensor Polarized Targets at TRIUMF 26

• 134º 76º G. Smith, March 2014 Tensor Polarized Targets at TRIUMF 27

Summary • G. Smith, March 2014 Tensor Polarized Targets at TRIUMF 28