SPIN2010. I.Meshkov 1, Yu.Filatov 1,2. Forschungszentrum Juelich GmbH. 19th International Spin Physics Symposium September 27 October 2, 2010

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1 Forschungszentrum Juelich GmbH SPIN200 9th International Spin Physics Symposium September 27 October 2, 200 Jülich, Germany Polarized Hadron Beams in NICA Project I.Meshkov, Yu.Filatov,2 JINR, Dubna 2 Moscow Institute for Physics and Technology

2 Contents Introduction: ti physics at NICA. Facility scheme and operation scenario 2. Polarized protons and deuterons acceleration in Nuclotron 3. Polarized particle dynamics in NICA Collider 4. Luminosity of p p and d d colliding beams Conclusion 2 I.Meshkov, Yu.Filatov Polarized Beams in NICA, SPIN200, Sep 27-Oct02, 200, Juelich

3 Introduction: Physics at NICA Spin Physics at NICA The SPD program includes the studies of Drell-Yan processes, J/Ψ production processes, Spin effects in elastic p p, p d and d d scattering, Spin effects in inclusive high-pt reactions, Polarization effects in heavy ions collisions. i See Report by A.Nagaytsev, Friday, October THE SPIN PHYSICS DETECTOR- SPD to study spin structure of the nucleon and polarization effects at NICA (Conceptual Design Report) S i ff t i l ti d (Conceptual Design Report) Polarized beams of protons and deuterons: (both longitudinal and transverse polarizations) p p s pp = 2 27 GeV (5 2.6 GeV kinetic energy ) JINR Dubna 200 d d s NN = GeV (2 5.9 GeV/u ion kinetic energy ) Laverage E30 cm-2 s- (at s pp = 27 GeV) pp 3 I.Meshkov, Yu.Filatov Polarized Beams in NICA, SPIN200, Sep 27-Oct02, 200, Juelich

4 . Facility Scheme and Operation Scenario NICA Layout MPD 2.5 m 4.0 m Booster SPI & LU-20 ( Old linac) Synchrophasotron yoke Nuclotron beam transfer line Nuclotron Spin Physics Detector (SPD) Beam transfer lines & New research area 4 I.Meshkov, Yu.Filatov Polarized Beams in NICA, SPIN200, Sep 27-Oct02, 200, Juelich

5 . Facility Scheme and Operation Scenario (Contnd) Polarized proton acceleration (Contnd) Source of Polarized Ions (SPI) LU-20: ions/pulse of d (5 MeV/u) or p 20 MeV Collider (45 Tm) Storage of 30 bunches by x0 9 p per ring at 5-2 GeV, No cooling! Booster (25 Tm) (2-3) single-turn injection, storage of p, acceleration up to 50 MeV, electron cooling, extraction IP- Two SC collider rings IP-2 Below st dangerous resonance in the Booster To be analyzed! 2х30 injection cycles Nuclotron (45 Tm) injection of one bunch of. 0 9 ions, acceleration up to 2 GeV max. I.Meshkov, Yu.Filatov, Polarized Beams in NICA, SPIN200, Sep 27-Oct 02, 200, Juelich 5

6 2. Polarized Protons and Deuterons Acceleration in Nuclotron Type of resonance Spin resonances Resonance condition Total number of resonances at acceleration p 0 2 GeV d 0 6 GeV/u.Intrinsic res. ν spin = kp ± Q y Integer res. ν spin = k 25 3.Nonsuperperiodic ν spin = m ± Q y, m kp (5.6 GeV/u) Coupling res. ν spin = m ± Q x 49 2 ν spin spin precession tune, Q x,y - betatron tunes p k, m integers, p number of superperiods (8 for Nuclotron) Power of the spin resonances: w,2 >> w 3,4 Thus, no problem for d acceleration in Nuclotron 6 I.Meshkov, Yu.Filatov Polarized Beams in NICA, SPIN200, Sep 27-Oct02, 200, Juelich y

7 2. Polarized Protons and Deuterons Acceleration in Nuclotron db/dt = T/s Spin resonances at Nuclotron.Intrinsic res. ν spin = kp ± Q y lg(w/wd ) 2.Integer res. ν spin = k lg(w/w D ) E p,gev w D = w D = E p,gev Here w is the resonance strength: w ~ /(2n θ ), where n θ is turn number at exact resonance that is sufficient for spin overturn (at db/dt = 0!). w D is the resonance strength that produces full depolarization at free crossing of the resonance at given crossing speed at given db/dt (or dγ/dt). (In other words: one has to choose a crossing speed and calculate w D for it; then to compare actual resonance strength w with w D ) 7 I.Meshkov, Yu.Filatov Polarized Beams in NICA, SPIN200, Sep 27-Oct02, 200, Juelich

8 2. Polarized Protons and Deuterons Acceleration in Nuclotron db/dt = T/s Spin resonances at Nuclotron lg(w/w D ) 3. Nonsuperperiodic res. ν spin = m ± Q y, m kp E p,gev lg(w/w D ) 4. Coupling res. ν spin = m ± Q x, m kp E p,gev w D = w D = D Not any resonance is dangerous! There are three Types of Spin resonances at Nuclotron: above blue line strong resonance: particle crosses it without polarization loss (regime of adiabatic a at crossing, see further), r), below green line a weak resonance, particle crosses it free, between both lines intermediate (see further). I.Meshkov, Yu.Filatov, Polarized Beams in NICA, SPIN200, Sep 27-Oct 02, 200, Juelich 8

9 2. Polarized Protons and Deuterons Acceleration in Nuclotron Not any resonance is dangerous! db/dt = T/s Dangerous db/dt = T/s resonances Spin s are resonances marked with at Nuclotron red caps.intrinsic res. ν lg(w/w D ) lg(w/w D ) spin = kp ± Q y 2.Integer res. ν spin = k 2 4 lg(w/w D ) E p,gev w D = w D = E p,gev 3. Nonsuperperiodic res. ν spin = m ± Q y, m kp E p,gev lg(w/w D ) 4. Coupling res. ν spin = m ± Q x, m kp E p, GeV w D = w D = I.Meshkov, Yu.Filatov, Polarized Beams in NICA, SPIN200, Sep 27-Oct 02, 200, Juelich 9

10 2. Polarized Protons and Deuterons Acceleration in Nuclotron (Contnd) Polarized proton acceleration in Nuclotron: Transparent Crossing of spin resonances J = m after J befor J is a Spin Adiabatic Invariant, i.e. projection to the periodical n-axis 0 I.Meshkov, Yu.Filatov, Polarized Beams in NICA, SPIN200, Sep 27-Oct 02, 200, Juelich

11 2. Polarized Protons and Deuterons Acceleration in Nuclotron (Contnd) n y Polarized proton acceleration in Nuclotron: Transparent Crossing of spin resonances Spin Tune Control System (STCS) x Solenoid Dipole Solenoid Dipole Solenoid Dipole Solenoid s B B s B x B s x B x y Dynamics of the Spin Orbit Vector (SOV) n s ν Spin = ϕ x ϕ y /2π per turn, ϕ x, ϕ y << Closed orbit distortion less than 0,5 cm I.Meshkov, Yu.Filatov, Polarized Beams in NICA, SPIN200, Sep 27-Oct 02, 200, Juelich x

12 2. Polarized Protons and Deuterons Acceleration in Nuclotron (Contnd) Polarized proton acceleration in Nuclotron (Contnd) STCS parameters Parameter Dipole Solenoid Number of elements x + 2x x + 2x0.5 5 Regime Pulsed mode Cycling mode Winding type Normal l Superconductive d Pulse duration (period) ~ 320 µsec ~ 4 sec Repetition rate, s - ~ Length, mm L total 3.5 m Aperture, mm hor ver Magn. field, T Max. current, ka Max. M. voltage g kv V (SC) ( ) 2 I.Meshkov, Yu.Filatov, Polarized Beams in NICA, SPIN200, Sep 27-Oct 02, 200, Juelich

13 2. Polarized Protons and Deuterons Acceleration in Nuclotron (Contnd) Polarized proton acceleration in Nuclotron (Contnd) Proton Energy Spread Limitation at Transparent Crossing of a Resonance The condition to be met: if γ < γ w D γ when γ < γ w D D<0, D 0 if when D<0,0 D 0 D, D 0 the beam depolarization at the transparent resonance crossing 2γ with STCS application and without it, correspondingly. That gives at db/dt = T/s at 2 T dipole field γ 7,3 4 γ 4 D<0, D 0 if < 0 or <,2 0 γ γ γ 7,3 4 γ 5 D<0, D 0 if < 0 or < 6 0 γ γ γ γ (E=5GeV), (E=5GeV), γ γ γ < 5 0 γ < 2, (E=2GeV) (E=2GeV) However, such a low p/p requires e-cooling application (!) that is available at The Booster. 3 I.Meshkov, Yu.Filatov, Polarized Beams in NICA, SPIN200, Sep 27-Oct 02, 200, Juelich

14 An 2. Polarized option: acceleration Protons and up to Deuterons 5 GeV and Acceleration extraction into Nuclotron collider for Not any resonance is dangerous! further acceleration (revolution frequency variation.3%) up to 2 GeV max. Dangerous db/dt = T/s resonances Spin are resonances marked with at Nuclotron Depolarization at acceleration s in the collider red is suppressed caps.intrinsic res. ν spin = kp ± Q y lg(w/w by Siberian D ) Snake (see further) lg(w/w D ) 2 2.Integer res. ν spin = k 4 lg(w/w D ) E p,gev w D = w D = E p,gev 3. Nonsuperperiodic res. ν spin = m ± Q y, m kp lg(w/w D ) 4. Coupling res. Then depolarization after transparent crossing of all 8 E p resonances,gev is < 5% ν spin = m ± Q x, m kp E p, GeV w D = w D = I.Meshkov, Yu.Filatov, Polarized Beams in NICA, SPIN200, Sep 27-Oct 02, 200, Juelich

15 3. Polarized Particle Dynamics in NICA Collider Longitudinal na and transverse rs polarization on formation on Second part of Siberian Snake with longitudinal axis First part of Siberian Snake with longitudinal axis π/4 -π/4 Spin rotators around vertical direction by π/4 Spin rotators around vertical direction by -π/4 π/4 -π/4 5 I.Meshkov, Yu.Filatov Polarized Beams in NICA SPIN-Praha-200 July 23-28, 200 Praha

16 3. Polarized Particle Dynamics in NICA Collider (Contnd) Longitudinal na Polarization on Formation: on Dipole Dpo Siberian ran Snake (Contnd) y x s B x B y First part of Siberian Snake with longitudinal axis -B x -B y B x -B y st half of the Snake: protons, 5.4 GeV (γ = 6), 4 dipoles x m, B max = 5 T, L total = 5.64 m 6 I.Meshkov, Yu.Filatov, Polarized Beams in NICA, SPIN200, Sep 27-Oct 02, 200, Juelich

17 3. Polarized Particle Dynamics in NICA Collider (Contnd) Longitudinal na Polarization on Formation: on Dipole Siberian Snake (Contnd) Second part of Siberian Snake with longitudinal axis y x s B y B y -B x B x -B y -B x 2 nd half of the Snake: protons, 5.4 GeV (γ = 6), 4 dipoles x m, B max = 5 T, L total = 5.64 m 7 I.Meshkov, Yu.Filatov, Polarized Beams in NICA, SPIN200, Sep 27-Oct 02, 200, Juelich

18 3. Polarized Particle Dynamics in NICA Collider Transverse Polarization Formation: Radial Polarization The scheme of vertical spin rotator by π/4 Total length of vertical spin rotator by Pi/2 is 2X4,4m 8 I.Meshkov, Yu.Filatov, Polarized Beams in NICA, SPIN200, Sep 27-Oct 02, 200, Juelich

19 3. Polarized Particle Dynamics in NICA Collider (Contnd) Longitudinal na polarization on injection scheme ( BL) dipole α ( γ ) = + γ a S B ρ ( ) ion ( ) S Upper ring n Dipole B Lower ring n Dipole B 9 I.Meshkov, Yu.Filatov, Polarized Beams in NICA, SPIN200, Sep 27-Oct 02, 200, Juelich

20 4. Luminosity of p p colliding beams Parameters of polarized proton beams in collider Energy, GeV 5 2 Proton number per bunch 6E0.5E0 Rms relative momentum spread 0E-3 0E-3 Rms bunch length, m Rms (unnormalized) emittance, π mm mrad mrad Beta-function in the IP, m Lasslet tune shift Beam-beam parameter Number of bunches 0 0 Luminosity, cm -2 s -.E30.E30 20 I.Meshkov, Yu.Filatov, Polarized Beams in NICA, SPIN200, Sep 27-Oct 02, 200, Juelich

21 5. SPD short description Conclusion: Realization of polarized beam program at Nuclotron and Collider looks feasible. Its development will bring experimental studies in spin physics at JINR to a new level. Thank you for your attention! 2 I.Meshkov, Yu.Filatov, Polarized Beams in NICA, SPIN200, Sep 27-Oct 02, 200, Juelich