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Measurement of tensor analyzing powers in deuteron photodisintegration. Dmitri Toporkov Budker Institute of Nuclear Physics Novosibirsk, Russia SPIN2004, Trieste, Italy October 15, 2004. Introduction Physical motivation Experimental arrangement Polarized target Detector Results
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Measurement of tensor analyzing powers in deuteron photodisintegration Dmitri Toporkov Budker Institute of Nuclear Physics Novosibirsk, Russia SPIN2004, Trieste, Italy October 15, 2004
Introduction • Physical motivation • Experimental arrangement • Polarized target • Detector • Results • Conclusions Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
Novosibirsk Electron-Deuteron Collaboration L.M.Barkov, V.F.Dmitriev, M.V.Dyug, L.G.Isaeva, A.V.Grigoriev,B.A.Lazarenko, S.I.Mishnev, D.M.Nikolenko, I.A.Rachek, R.Sh.Sadykov, Yu.V.Shestakov, D.K.Toporkov and S.A.Zevakov BINP, Novosibirsk, Russia A.Yu.Loginov, A.N.Osipov, A.A.Sidorov and V.N.Stibunov INR, Tomsk, Russia R.Gilman Rutgers University, Piscataway, NJ, USA E.R.Kinney Colorado University, Boulder, CO, USA R.J.Holt and D.H.Potterveld ANL, Argonne, IL, USA C.W.de Jager1 and H. de Vries NIKHEF, Amsterdam, The Netherlands S.L.Belostotsky, V.V.Nelyubin and V.V.Vikhrov INP, St.-Petersburg, Russia H.Arenhovel IKP, Johanness Gutenberg-Universitat, Mainz, Germany 1Present address: TJNAF,Newport News, VA, USA Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
Novosibirsk electron-positron facility VEPP-3 Energy : 2000 MeV Lifetime : 14000 s Av. current : 100 mA Bunch : 0.7x0.3 mm Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
Photodisintegration of polarized deuteron Scattering angle is small, therefore q2 close to zero and photon is almost real. Process is photodisintegration Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
Definition of kinematic variables for the reaction ( d, pn) in the center of mass frame Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
Top view of the internal target at VEPP-3 electron ring Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
Cryogenic Atomic Beam Source Cryostat Liquid nitrogen Turbo pump Tenzor polarization Vector polarization Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
ABS just before the installation at the straight section Magnetic pole tip field of superconducting magnet up to 4.8 T Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
Storage cell for polarized atoms Beam flux of polarized deuterium atoms 8.2x1016 at/sec The measured target thickness 8x1013 at/cm2 Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
The layout of the detector system, side view 200x200x1000 mm 120x400x1000 mm Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
LQ polarimeter feature Asymmetry in elastic ed scattering at small transfered momentum, centered at = 9.3, Q = 0.105 (GeV/C) ○ 2 2 At small momentum transfers T ≈ -√2/3 Q Q Q = 0.2859 fm - deuteron static quadrupole moment 2 20 D 2 D 2 2 At Q = 0.105 (GeV/C) all 'reasonable' theoretical predictions for T contain within ±5% range 20 An absolute measurement of T performed at NIKHEF, further constraining models 20 Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
The average degree of target polarization during the run was found to be LQP Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
Beam life-time in the VEPP-3 ring during the experiment Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
Charge accumulation during the experiment Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
Neutron: TOF, charge veto Proton: TOF, DE/E Kinematic correlations: p-n energy p-n polar angle p-n azimuthal angle Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
Preliminary results on T20 with =83-93(full circles)and old data Phys.Lett. B302 (1993) 277 (open circles) K.-H.Schmitt and H. Arenhovel, Few-Body Syst. 7(1989)95 Yu.P.Melnik and A.V.Shebeko, PRC 48(1993)23 L=1.2Gev ibid L=4mp M.I.Levchuk, Few-Body Syst. 19(1995)77 Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
Preliminary results on T21 and T22 with =83-93(full circles)and old data Phys.Lett. B302 (1993) 277 (open circles) K.-H.Schmitt and H. Arenhovel, Few-Body Syst. 7(1989)95 Yu.P.Melnik and A.V.Shebeko, PRC 48(1993)23 L=1.2Gev ibid L=4mp M.I.Levchuk, Few-Body Syst. 19(1995)77 Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
Preliminary results on T20, T21 and T22 measurement E 25-45 MeV 45-65 MeV 65-100 MeV K.-H.Schmitt and H. Arenhovel full M.I.Levchuk full Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
Preliminary results on T20, T21 and T22 measurement E 100-150 MeV 150-250 MeV 250-400 MeV K.-H.Schmitt and H. Arenhovel full M.I.Levchuk full Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
Part of people, who did the experiment Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration