Status update of n- 3 He experiment DOE FnPB Review, ORNL D. Bowman, S. Penttila Oak Ridge National Laboratory M. Gericke University of Manitoba C. Crawford, Y. Shin University of Kentucky

DOE FnPB Review, ORNL, #2 Outline  Executive summary  Scientific motivation theory calculations statistical sensitivity systematics negligible  Experimental design experimental layout solenoid design spin flipper design 3 He target / drift chamber R&D at LANL  Experimental team  Projected schedule  Funding profile  FnPB infrastructure needed  Summary

DOE FnPB Review, ORNL, #3 Executive summary  n- 3 He experiment approved by the FnPB PRAC, first measurement of PV in the n- 3 He reaction  recent progress in experimental design full 4-body calculation of PV observable R&D projects on target/detector design at LANL new spin flipper design permitting compact / less expensive layout preliminary holding field design  leverage existing hardware / technology major components based on similar NPDGamma instrumentation can reuse NPDGamma electronics / power supplies  capable experimental team experience on hadronic PV experiments at LANL  funding profile University of Manitoba $100k target / drift chamberNSERC funded University of Kentucky$ 57k DAQ / electronics DOE-OJI proposal ORNL operation$120k solenoid, spin flipper, shielding, alignment, design  FnPB infrastructure no safety hazards, no LH 2 target, new power or cooling requirements minimal modification of FnPB cave – stand for n- 3 He solenoid technician support for readiness review preparation, setup of experiment

DOE FnPB Review, ORNL, #4 Hadronic Weak Interaction (HWI) N N N N Meson exchange STRONG (PC) WEAK (PV) p-p and nuclei Meson Exchange model (DDH) Effective Field Theory (EFT)

DOE FnPB Review, ORNL, #5 n- 3 He PV Asymmetry ~ k n very small for low-energy neutrons - essentially the same asym. - must discriminate between back-to-back proton-triton S(I):  4He J  =0 + resonance  sensitive to EFT coupling or DDH couplings  ~10%  I=1 contribution (Gerry Hale, qualitative) PV observables: Tilley, Weller, Hale, Nucl. Phys. A541, 1 (1992)

DOE FnPB Review, ORNL, #6 Theoretical calculations – progress  Vladimir Gudkov (USC)PVA = 3£10 -7 PV reaction theory  Gerry Hale (LANL) PC A y (90 ± ) = -1.7 ± 0.3£10 -6 R matrix calculation of PC asymmetry, nuclear structure, and resonance properties  Anna Hayes (LANL) No-core shell model calculation with AV18 potential, etc.  Michele Viviani et al. (INFN Pisa)PVA = 3£10 -7 full 4-body calculation of scattering wave function calculation of asymmetry within DDH framework progress on calculation of EFT low energy coefficients preliminary – still improving convergence of 0 + wave functions

DOE FnPB Review, ORNL, #7 Experimental sensitivity to DDH couplings n+ 3 He  t+p (ppm) Viviani et al. preliminary A z cont.

DOE FnPB Review, ORNL, #8  - metal shield 1010 steel flux return 10 Gauss solenoid RF spin rotator 3 He target / ion chamber supermirror bender polarizer (transverse) FnPB cold neutron guide 3 He Beam Monitor transition field (not shown) FNPBn- 3 He Experimental setup  longitudinal holding field – suppressed PC asymmetry  RF spin flipper – negligible spin-dependent neutron velocity  3 He ion chamber – both target and detector

DOE FnPB Review, ORNL, #9 Solenoid holding field  uniformity requirements  B~ 0.3 G  ¢  B/2E n = <  A z  z ~ 0.1 ±  + alignment of wires  preliminary design solenoid with compensation coils at end for uniformity  -metal shield for residual earth’s field 1010 steel flux return to prevent saturation of  -metal  design parameters 3 m length x 50 cm diameter B =10 G for spin flipper j = 9 A/cm winding density I 0 = 1560 A (or end-cap windings)  simulation using COMSOL 1010 steel flux return 10 Gauss solenoid 4 m £ 55 cm diam.3 m £ 50 cm diam. I 0 = A turns I0I0 j = 8+1 A/cm

DOE FnPB Review, ORNL, #10 red - transverse field lines blue - end-cap windings Radio frequency spin rotator  extension of design for NPDGamma P-N Seo et al., Phys. Rev. ST Accel. Beam, vol 11, (2008)  new resonator for n-3He experiment transverse horizontal RF B-field longitudinal / transverse flipping no fringe field - 100% efficiency compact geometry - efficient -small diameter solenoid matched to driver electronics for NPDGamma spin flipper  prototype design parasitic with similar design for nEDM guide field near cryostat fabrication and testing at UKy – 2009 NPDGamma windings n- 3 He windings Magnetostatic calculation with COMSOL

DOE FnPB Review, ORNL, #11 3 He target / ion chamber  MC simulations of sensitivity to proton asymmetry including wire correlations  A ~ 6 /pN  tests at LANSCE FP12 fission chamber flux calibration prototype drift chamber R&D new beam monitors for SNS  design of new ion chamber for NPDGamma, test at LANL

DOE FnPB Review, ORNL, #12 LANSCE FP12 absolute neutron flux

DOE FnPB Review, ORNL, #13 LANSCE FP12 3 He chamber R&D

DOE FnPB Review, ORNL, #14 Left: LANL FP12 beam line with new beam monitor Below: new beam monitor signal at 100 mA proton beam current and neutron beam cross-section. Inverted Signal LANSCE FP12: test of NPDGamma monitors

DOE FnPB Review, ORNL, #15 Comparison of beam monitors New monitors for SNS Old monitors used for NPDGamma at FP12 (same gain) RMS

DOE FnPB Review, ORNL, #16 n- 3 He collaboration  J.D. Bowman (PI), S.I. Penttilä Oak Ridge National Laboratory  M.T. Gericke (PI), S.A. Page, Mark McCrea University of Manitoba  C.B. Crawford (PI), Y. Shin, E. Martin University of Kentucky  C. Gillis, J. Mei Indiana University  J. Martin University of Winnipeg  V. Gudkov University of South Carolina  M. Viviani INFN, Sezione di Pisa  A. Klein, A. Salas-Bacci, A. Hayes, G. Hale Los Alamos National Lab  R. Mahurin University of Tennessee  P.-N. Seo Triangle Universities Nuclear Lab  L. Barron Universidad Nacional Autónoma de México

DOE FnPB Review, ORNL, #17 Projected schedule  Jan 2010 – Jan 2011 NPDGamma data-taking  Aug 2010 – Dec 2010 Construction of solenoid Test of field uniformity, alignment procedures  Feb 2011 – Mar 2011 Installation at FnPB Commissioning  Apr 2011 – Sept He data-taking  June 2009 – Aug 2010 Construction of new RFSF resonator at ORNL Construction of 3 He ion chamber at Univ. Manitoba DAQ electronics and software production at Univ. Kentucky  Sept 2010 – Nov 2010 test RFSF, 3 He chamber, and DAQ at LANL FP12 window of opportunity for the n- 3 He experiment between NPDGamma and Nab (2011) ORNLOffsite, LANL

DOE FnPB Review, ORNL, #18 Funding Profile  University of Manitoba $100kNSERC funded target / drift chamber $500k for FnPB-related activities in last 2 years  University of Kentucky$ 57k DOE-OJI proposal DAQ / electronics $40k university funding for R&D  ORNL operations $120k solenoid, spin flipper neutron, gamma shielding design, stands, alignment technician support

DOE FnPB Review, ORNL, #19 Requirement of FnPB infrastructure  modification of FnPB retained equipment: -polarizer, beam monitor, spin flipper electronics -computer interface to chopper and TOF from SNS -DC holding field supply -beam collimation and shielding, beam stop support stand for solenoid -possible reuse of NPDGamma detector motion stand power & cooling requirements -same as NPDGamma  manpower shielding calculations, preparation for readiness review 1 month technician support for setup of experiment  safety hazards – none 3 He target – 1 atm inert gas; n+ 3 He  t+p (no  radiation) radiation shielding: polarizer is still the major background

DOE FnPB Review, ORNL, #20 Conclusion  by doing NPDGamma, n- 3 He experiments along with existing p-p, p- , n-  (few body systems) we can significantly improve statistical uncertainties in DDH couplings and eliminate nuclear structure uncertainties  EFT calculations are in progress for few-body systems  n- 3 He is on-track to run after NPDGamma