1 measurement of tensor analyzing powers in deuteron photodisintegration dmitri toporkov budker...
TRANSCRIPT
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Measurement of tensor analyzing powers
in deuteron photodisintegration
Dmitri ToporkovDmitri Toporkov
Budker Institute of Nuclear Budker Institute of Nuclear PhysicsPhysics
Novosibirsk, RussiaNovosibirsk, Russia
SPIN2004, Trieste, ItalySPIN2004, Trieste, Italy
October 15, 2004October 15, 2004
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1. Introduction2. Physical motivation3. Experimental arrangement4. Polarized target5. Detector6. Results 7. Conclusions
Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
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Novosibirsk Electron-Deuteron CollaborationL.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, RussiaA.Yu.Loginov, A.N.Osipov, A.A.Sidorov and V.N.Stibunov
INR, Tomsk, RussiaR.Gilman
Rutgers University, Piscataway, NJ, USAE.R.Kinney
Colorado University, Boulder, CO, USAR.J.Holt and D.H.Potterveld
ANL, Argonne, IL, USAC.W.de Jager1 and H. de Vries
NIKHEF, Amsterdam, The NetherlandsS.L.Belostotsky, V.V.Nelyubin and V.V.Vikhrov
INP, St.-Petersburg, RussiaH.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
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VEPP-3Energy : 2000 MeVLifetime : 14000 sAv. current : 100 mABunch : 0.7x0.3 mm
Novosibirsk electron-positron facility
Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
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Photodisintegration of polarized deuteron
eAngle is small
Photon is almost real
2 *020
* * 2 * *21 22
1 11 (3cos 1)
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3 3sin 2 cos sin cos 2
8 8
{
}
ZZ
ddP T
d d
T T
Scattering angle is small, therefore q2 close to zero andphoton is almost real. Process is photodisintegration
Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
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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
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Top view of the internal target at VEPP-3 electron ring
Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
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Cryogenic Atomic Beam Source
Liquid nitrogen
Tenzor polarizationVector polarization
CryostatCryostat
Turbopump
Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
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ABS just before the installation at the straight sectionABS just before the installation at the straight section
Magnetic pole tip field of superconducting magnet up to 4.8 T
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Storage cell for polarized atoms
Beam flux of polarized deuterium atoms 8.2x1016 at/secThe measured target thickness 8x1013 at/cm2
Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
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The layout of the detector system, side view
A - tangstem convertorB - brass baseC - scintillation fibers
Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
200x200x1000 mm
120x400x1000 mm
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Asymmetry in elastic ed scattering at small transfered momentum, centered at = 9.3, Q = 0.105 (GeV/C)○ 2 2
At small momentum transfersT ≈ -√2/3 Q QQ = 0.2859 fm - deuteron static quadrupole moment
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D
2D
2
e
At Q = 0.105 (GeV/C) all 'reasonable' theoretical predictions for T contain within ±5% range
2 2
An absolute measurement of T performed at NIKHEF, further constraining models
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LQ polarimeter feature
Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
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The average degree of targetpolarization during the run was found to be
+zzP = 0.378 ± 0.022
LQP
Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
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τ =8000sectarget
τ =20000secnotarget
Beam life-time in the VEPP-3 ring during the experiment
Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
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Charge accumulation during the experiment
Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
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Proton: F, E/E Neutron: F, charge veto
Kinematic correlations:p-n energyp-n polar angle
p-n azimuthal angle
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Preliminary results on T20 with = 83-93 (full circles) and old data Phys.Lett. B302 (1993) 277 (open circles)
Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
K.-H.Schmitt and H. Arenhovel, Few-Body Syst. 7(1989)95 Yu.P.Melnik and A.V.Shebeko, PRC 48(1993)23 =1.2Gev ibid =4m
M.I.Levchuk, Few-Body Syst. 19(1995)77
cmp
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Preliminary results on T21 and T22 with =83-93 (full circles) and old data Phys.Lett. B302 (1993) 277 (open circles)
Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
K.-H.Schmitt and H. Arenhovel, Few-Body Syst. 7(1989)95 Yu.P.Melnik and A.V.Shebeko, PRC 48(1993)23 =1.2Gev ibid =4m
M.I.Levchuk, Few-Body Syst. 19(1995)77
cmp
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Preliminary results on T20, T21 and T22 measurement
E 25-45 MeV 45-65 MeV 65-100 MeV
Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
K.-H.Schmitt and H. Arenhovel fullM.I.Levchuk full
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Preliminary results on T20, T21 and T22 measurement
E 100-150 MeV 150-250 MeV 250-400 MeV
Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration
K.-H.Schmitt and H. Arenhovel fullM.I.Levchuk full
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