NPS Cllabratin Meeting JLab, Newprt News, VA 21 January 2016 T. Hrn
The Neutral-Particle Spectrmeter (NPS) NPS PbWO 4 The NPS is envisined as a facility in Hall C, utilizing the well-understd HMS and the SHMS infrastructure, t allw fr precisin (cincidence) crss sectin measurements f neutral particles (γ and π 0 ). NPS cantelevered ff SHMS platfrm NPS n SHMS platfrm Magnet Detectr Detectr Magnet NPS angle range: 5.5 30 degrees NPS angle range: 25 60 degrees Scientific prgram: 5 experiments apprved by PAC (40, 42) t date E12-14-003 Wide-angle Cmptn Scattering at 8 and 10 GeV Phtn Energies E12-14-005 Wide Angle Exclusive Phtprductin f π 0 Mesns E12-14-006 Initial State Helicity Crrelatin in Wide-Angle Cmptn Scattering E12-13-007: Measurement f Semi-inclusive π 0 prductin as Validatin f Factrizatin E12-13-010 Exclusive Deeply Virtual Cmptn and π 0 Crss Sectin Measurements in Hall C
NSAC 2015 Lng Range Plan Precisin measurements in semi-inclusive pin and kan prductin frm unplarized, as well as lngitudinally and transversely plarized prtn targets in the JLab 12 GeV era will allw access t bth flavr and spin dependent transverse mmentum distributins in the valence quark regin. Multiple instruments bring essential elements t this campaign: HMS-SHMS and the NPS Sme f the mst imprtant tls fr describing hadrns are Generalized Partn Distributins, [which] can be investigated thrugh the analysis f hard exclusive prcesses The HMS-SHMS [and] the NPS will allw refined high reslutin imaging f the nuclen s internal landscape
NPS General Design Cncept a ~25 msr neutral particle detectr cnsisting f up t 1116 PbWO 4 crystals in a temperature-cntrlled frame including gain mnitring and curing systems HV distributin bases with built-in amplifiers fr peratin in a high-rate envirnment Essentially deadtime-less digitizing electrnics t independently sample the entire pulse frm fr each crystal JLab-develped Flash ADCs A new sweeping magnet allwing fr small-angle peratin at 0.3 Tm (fr electr-prductin) and large angle peratin at 0.6 TM (fr pht-prductin). The magnet is cmpatible with existing JLab pwer supplies. Cantelevered platfrms ff the SHMS carriage t allw fr remte rtatin (in the small angle range), and platfrms t be n the SHMS carriage (in the large angle range) new Mdified beam pipe: critical angle 13.5 mr A beam pipe with as large critical angle as pssible t reduce beamline-assciated backgrunds further study shwed nly a small sectin needs mdificatin (JLab/Hall C) 4
NPS Prject Status NPS PbWO 4 2015 NSF/MRI funding prpsal was selected fr an award Award will prvide fr NPS infrastructure, including the magnet, assuming existing crystals Additinal UK award (D. Hamiltn) with emphasis n additinal equipment aimed at WACS requirements Significant effrts f the NPS cllabratin have recently been related t PbWO 4 crystals See talk by C. Munz-Camach Als much prgress n prcurement and plans fr machining magnet steel See talk by M. Fwler Onging effrts n develpment f a cmpact phtn surce and additinal experiments See talks by J. Zhang, G. Niculescu, and A. Mkrtchyan and M. Ber Alternative HV base designs have been explred See talk by C. Hyde
Gals f this meeting Frmulate a plan fr NPS cnstructin items ver the next year Discuss the timeline f engineering and design fr NPS Discuss ptimizatin f NPS cmpnents Discussin f PbWO4 availability and future use f PbWO4 at an EIC Discussin f PMT availability Frame design and cling Discuss path frward fr phtn surce and future experiments with NPS NPS cllabratin frmalities Publicatin f crystal testing results Rad twards defining crystal quality
UPDATES Agenda 8:45 9:00 Welcme and Plans fr the Day 9:00 9:25 Prgress with crystal testing and selectin Carls Munz-Camach PbWO4 crystals at an EIC Pawel Nadel-Turnski 9:25 9:50 Magnet design Mike Fwler/Paul Brindza 9:50 10:15 PMT HV divider Charles Hyde 10:15 10:45 Cffee Break PHOTON SOURCE AND EXPERIMENTS 10:45 11:10 Phtn Surce fr WACS experiments I Jixie Zhang 11:10 11:35 Phtn Surce fr WACS experiments II Gabriel Niculescu and B. Wjtsekhwski 11:35 12:00 TCS with phtn beam in Hall A/C Arthur Mkrtchyan and Marie Be
EXP. NO. Hall Title Spkespersns Institutins Beam Days Rating PAC Run Grup E12-13-007 C Measurement f Semi-Inclusive π Prductin as Validatin f Factrizatin E12-13-010 C Exclusive Deeply Virtual Cmptn and Neutral Pin Crss-Sectin Measurements in Hall C E12-14-003 C Wide-angle Cmptn Scattering at 8 and 10 GeV Phtn Energies E12-14-005 C Wide Angle Exclusive Phtprductin f π Mesns E12-14-006 C Initial State Helicity Crrelatin in Wide-Angle Cmptn Scattering R. Ent JLab 25 A- 40 A T. Hrn CUA H. Mkrtchyan Yerevan V. Tadevsyan Yerevan C. Munz Camach IPN Orsay 53 A 40 A R. Paremuzyan IPN Orsay T. Hrn CUA C. Hyde ODU J. Rche Ohi U B. Wjtsekhwski JLab 18 A- 42 B D. Hamiltn Glasgw S. Sirca Ljubljana D. Dutta Miss. State 18 B 42 B M. Amaryan ODU H. Ga Duke M. Kunkel ODU S. Sirca Ljubljana I. Strakvsky GWU D. Keller UVa 15 B 42 C D. Day UVa J. Zhang UVa Apprved PAC days 129 Run Grup days 86