12 Ge V MOLLER UPDATE TO THE HALL

  • Slides: 24
Download presentation
12 Ge. V MOLLER UPDATE TO THE HALL A COLLABORATION Juliette M. Mammei

12 Ge. V MOLLER UPDATE TO THE HALL A COLLABORATION Juliette M. Mammei

OUTLINE Physics motivation Description of the experiment Update on spectrometer design Hall A Summer

OUTLINE Physics motivation Description of the experiment Update on spectrometer design Hall A Summer 2011 Collaboration Meeting (since Magnet Advisory Meeting) Status and Future Plans 2

PV MOLLER SCATTERING e- e- e- Hall A Summer 2011 Collaboration Meeting e- Z

PV MOLLER SCATTERING e- e- e- Hall A Summer 2011 Collaboration Meeting e- Z 0 e- e- 12 Ge. V MOLLER APV ≈ 35 ± 0. 7 ppb A SEARCH FOR NEW PHYSICS 3

COMPLEMENTARY TO THE LHC Hall A Summer 2011 Collaboration Meeting 0. 1% measurement of

COMPLEMENTARY TO THE LHC Hall A Summer 2011 Collaboration Meeting 0. 1% measurement of sin 2θW! 4 Petriello et. al. (2009)

COMPARISON TO QWEAK Qweak 35 cm, 2. 5 k. W 500 A/cm 2 0.

COMPARISON TO QWEAK Qweak 35 cm, 2. 5 k. W 500 A/cm 2 0. 8 GHz/sector 200 ± 5 ppb ~2 ppb Hall A Summer 2011 Collaboration Meeting Target Magnet Incident rate Asymmetry “Beam properties” MOLLER 150 cm, 5 k. W 1550 A/cm 2 20 GHz/sector 35 ± 0. 7 ppb ~0. 2 ppb 5

ERROR BUDGET Hall A Summer 2011 Collaboration Meeting o Dedicated measurements with auxiliary detectors

ERROR BUDGET Hall A Summer 2011 Collaboration Meeting o Dedicated measurements with auxiliary detectors • Q 2, transverse and inelastic asymmetries, pions o Careful design • beam properties (1 st and 2 nd order – work at laser table) • transverse (take advantage of cancellations) • neutrals (design a “ 2 -bounce” collimation system) o Improvements to polarimeters 6

THE EXPERIMENT two-toroid spectrometer (focus Møller electrons from 5. 5 -19 mrads) detectors located

THE EXPERIMENT two-toroid spectrometer (focus Møller electrons from 5. 5 -19 mrads) detectors located 28 m downstream (~150 GHz rate, <10% bkgd) 150 cm high power liquid hydrogen target 11 Ge. V, 75 μA beam Hall A Summer 2011 Collaboration Meeting N O I IT S K R N E D U ST D E T O W ID L O S 7 Picture thanks to Patrick Rogan, UMass undergrad

100% AZIMUTHAL ACCEPTANCE Identical particle scattering! e- Forward e- e- Backward Hall A Summer

100% AZIMUTHAL ACCEPTANCE Identical particle scattering! e- Forward e- e- Backward Hall A Summer 2011 Collaboration Meeting e- COM Frame e- e- ee- Lab Frame Backward Forward 8

TOSCA Commercial software available from Vector Fields for finite element analysis Tracking of particles

TOSCA Commercial software available from Vector Fields for finite element analysis Tracking of particles with no radiative effects Magnetic Forces Hall A Summer 2011 Collaboration Meeting CAD-like capability Physical layout of coils Support structure Export to step file Use GEANT 4 with a TOSCAgenerated field map 9

CONDUCTOR LAYOUT Biot-Savart calculation optimized current returns 3 L 3 R 4 L 4

CONDUCTOR LAYOUT Biot-Savart calculation optimized current returns 3 L 3 R 4 L 4 C 4 R 2 L 2 R Actual conductor layout 1 BL 1 BR Hall A Summer 2011 Collaboration Meeting 1 AL 1 AR 10

TRACKING IN TOSCA Hall A Summer 2011 Collaboration Meeting 11

TRACKING IN TOSCA Hall A Summer 2011 Collaboration Meeting 11

GEANT 4 RESULTS (ORIGINAL PROPOSAL MODEL) Radius (m) ϕ (degrees) θcm (degrees) Hall A

GEANT 4 RESULTS (ORIGINAL PROPOSAL MODEL) Radius (m) ϕ (degrees) θcm (degrees) Hall A Summer 2011 Collaboration Meeting θlab 12

GEANT 4 RESULTS (TOSCA MODEL – ACTUALCONDUCTOR LAYOUT) Radius (m) ϕ (degrees) θcm (degrees)

GEANT 4 RESULTS (TOSCA MODEL – ACTUALCONDUCTOR LAYOUT) Radius (m) ϕ (degrees) θcm (degrees) Hall A Summer 2011 Collaboration Meeting θlab 13

MAGNET STATS Upstream Hybrid Qweak Field Integral (T·m) 0. 15 1. 1 0. 89

MAGNET STATS Upstream Hybrid Qweak Field Integral (T·m) 0. 15 1. 1 0. 89 Total Power (k. W) 40 765 1340 Current per wire (A) 298 384 9500 Voltage per coil (V) 19 285 18 Current Density (A/cm 2) 1200 1550 500 Wire cross section (ID: water hole, in) 0. 229 x 0. 229 (0. 128) 2. 3 x 1. 5 (0. 8) Weight of a coil (lbs) 44 555 7600 Magnetic Forces (lbs) 100 3000 27000 Hall A Summer 2011 Collaboration Meeting Property 14

BACKGROUNDS Moller (GHz) Elastic ep (GHz) Inelastic ep (GHz) Background (%) Proposal 133 12

BACKGROUNDS Moller (GHz) Elastic ep (GHz) Inelastic ep (GHz) Background (%) Proposal 133 12 0. 4 9 TOSCA 155 14 0. 5 8 Other sources of background include: • scattering from aluminum target windows • multiple-bounce photons (minimize 1 -bounce) • neutrons • weak decays with large analyzing power To be studied with GEANT 4 simulation! Hall A Summer 2011 Collaboration Meeting Field Map 15

STATUS AND FUTURE PLANS Plan to do 3 runs: 14 PAC days – Achieve

STATUS AND FUTURE PLANS Plan to do 3 runs: 14 PAC days – Achieve statistical precision of E 158 � 95 PAC days – Focus on systematics, 25% statistical � 235 PAC days – All the kinks ironed out � FY 2011 MIE proposal to be submitted to DOE DNP by end of June (start of CD process) FY 2012 -13 Complete design and engineering FY 2014 -16 Construction funding 2016 Assembly in Hall for first run, ~3 months (commissioning + 14 PAC days) Hall A Summer 2011 Collaboration Meeting 16

EXTRA SLIDES Hall A Summer 2011 Collaboration Meeting 17

EXTRA SLIDES Hall A Summer 2011 Collaboration Meeting 17

SUPPORT STRUCTURE 7 m Hall A Summer 2011 Collaboration Meeting 3. 6 m 18

SUPPORT STRUCTURE 7 m Hall A Summer 2011 Collaboration Meeting 3. 6 m 18

JEFFERSON LAB N IO T I D E T N E D TU SO

JEFFERSON LAB N IO T I D E T N E D TU SO Picture thanks to Patrick Rogan, UMass undergrad Parity quality beam >85% using strained Ga. As photocathodes Upgrade to 12 Ge. V beam energy, addition of a new Hall “D” 12 Ge. V MOLLER will run in Hall A with an 11 Ge. V, 75 μA beam Hall A Summer 2011 Collaboration Meeting R O W LID S S K 150 cm high power liquid hydrogen target detectors located 28 m downstream (~150 GHz rate, <10% bkgd) two-toroid spectrometer (focus Møller electrons from 5. 5 -19 mrads) 19

TWEAKING THE OPTICS Beam (centered at x=0, y=0) Mott (ep) Hall A Summer 2011

TWEAKING THE OPTICS Beam (centered at x=0, y=0) Mott (ep) Hall A Summer 2011 Collaboration Meeting Moller (ee) Width of radial focus 25 Separation (cm) Width (cm) 20 Separation of ends 25 "Good" angles 15 10 5 0 "Good" angles. . . 20 15 10 5 0 0 2 4 6 Version 8 10 20

100% AZIMUTHAL ACCEPTANCE e- Forward e- e- Backward COM Frame e- e- ee- Lab

100% AZIMUTHAL ACCEPTANCE e- Forward e- e- Backward COM Frame e- e- ee- Lab Frame Backward Forward Hall A Summer 2011 Collaboration Meeting e- 21

SPIN PRECESSION AT JEFFERSON LAB Hall A Summer 2011 Collaboration Meeting 22

SPIN PRECESSION AT JEFFERSON LAB Hall A Summer 2011 Collaboration Meeting 22

ERROR BUDGET Simulation, dedicated tracking detectors Careful work at laser table, cancellation with helicity

ERROR BUDGET Simulation, dedicated tracking detectors Careful work at laser table, cancellation with helicity reversal Measurements of asymmetry between peaks Dedicated detectors Average over sectors, forward/backward cancellation Hall A Summer 2011 Collaboration Meeting Compton/ Moller polarimeters 23

OUTLINE Moller scattering Comparable to 2 highest energy exp. Description of the 12 Ge.

OUTLINE Moller scattering Comparable to 2 highest energy exp. Description of the 12 Ge. V MOLLER experiment apparatus High rate, small backgrounds – 150 GHz, 8% backgrounds Two toroids Novel toroid design (TOSCA and GEANT 4) Angular acceptance 5. 5 -19 mrads � 150 cm target, detectors at 28 m � Multiple current returns � High power � Hall A Summer 2011 Collaboration Meeting sin 2θW Interference of Z boson with single photon 24