1 measurement of tensor analyzing powers in deuteron photodisintegration dmitri toporkov budker...

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1 Measurement of tensor analyzing powers in deuteron photodisintegration Dmitri Toporkov Dmitri Toporkov Budker Institute of Nuclear Budker Institute of Nuclear Physics Physics Novosibirsk, Russia Novosibirsk, Russia SPIN2004, Trieste, Italy SPIN2004, Trieste, Italy October 15, 2004 October 15, 2004

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1

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)

22

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

7 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

10 Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration

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

20

20

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

17 Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration

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

22 Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration

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Part of Part of people, who did the experimentpeople, who did the experiment

Dmitri Toporkov Measurement of tensor analyzing powers SPIN2004,Trieste,Italy in deuteron photodisintegration