Spin Physics at IHEP, now and in future

1. Spin Physics at IHEP, now and in future V. Mochalov (for N. Tyurin)

2. IHEP experimental program • Three main experimental directions: • Test of SM and effects beyond SM in charge Kaon rare decays. • Hadron spectroscopy • Polarization effects. N. Tyurin, Director's session

3. Spin physics at Protvino • 1968 – first polarization program at IHEP • Polarization in elastic scattering • 1978 - JINR-IHEP polarized target • Polarization in charge exchange reactions • Single-spin asymmetry in inclusive production of neutral mesons. • 1993 - polarized beam from Λ-decay for FODS experiment • Single-spin asymmetry in inclusive production of charge hadrons. N. Tyurin, Director's session

4. Current experiments • FODS experiment to study inclusive charge hadron (π, K, p) production. • Future: study spin effects in pair production (study transversity). • PROZA-2 experiments – AN in π0 production in polarized target fragmentation region • Future – new SPASCHARM project π-p↑→π0X Preliminary, 2008 result pp↑→π0X, N. Tyurin, Director's session

5. New SPASCHARM project • Stage 1: precise study of single-spin asymmetry in miscellaneous inclusive and exclusive production of the light (u, d, s – quarks) resonances in the un-polarized beam fragmentation region. • New Setup is under construction to start the experiment in 2011. • Stage 2: measurements of double-spin asymmetry ALL using both longitudinally polarized proton beam and target in charmonium production to studygluon polarization G/G(x)at large xB (around 0.3). • A polarized proton beam is required. N. Tyurin, Director's session

6. SPASCHARM Expected accuracy (70 days at the beam) • Exclusive charge exchange reactions: • -р↑ ω(782)nand -р↑’(958)n – 20 times more statistics, statistic errors less than 2% • -pf2(1270) n– 3 times more statistics, statistic errors about 5% • Inclusive reactions: • Asymmetry measurement statistic errors in reactions -р↑ ω(782)X, ρX,’(958)X are 0.3÷3% for different kinematic intervals • Accuracy in the reaction -pf2(1270) Xis even better (0.1÷1%) N. Tyurin, Director's session

7. SPASCHARM Stage 2 • Stage 2 with “old” polarized target and without polarized beam: • Single-spin asymmetry АNin J/and1/2inclusive production using pion and unpolarized proton beam. Expected accuracy (conservative) for 40 days of data taking is: • Statistic error of J/asymmetry measurements is 14% for-and 5% for p beam. • The cross-section ratio for 1/2production will be measured to determine the mechanism of charmonium production. • Stage 2 with longitudinally polarized beam and target: • Main goal of the experiment is to measure double-spin asymmetry ALL using longitudinally polarized proton beam and target in the reactions p + p 2 + Xandp+pJ/+X • G/G(x)is clearly measured for 2 (JPC = 2++). Gluon-gluon fusion is supposed to be dominant in 2-production. G/G can be measured directly: ALL (xF) = ÂLL * [∆G/G (x1)*∆G/G (x2)], where • АNNmeasurements for Drell-Yan pairs to study transverslity h(x). SimultaneouslyАNN and AN in J/, 1/2. production will be studied. • Double spin asymmetry measurements at different channels N. Tyurin, Director's session

8. Accelerator development • Current IHEP accelerator activity is to accelerate light ions at U70. • 2D,12C nuclei are accelerated in 1.5 GeV booster and transported inside U70 at the injection energy in 2008. • The project to replace current U-70 magnet by Super Ferric 100 GeV accelerator is under discussion. • SF machine design will consider the possibility to accelerate polarized protons. • Polarized beam from Λ-decays: • FODS-2 experiment uses polarized beam from 1993 (Intensity 108 polarized p/cycles) • We are discussing possibility another low intensity polarized beam for SPASCHARM experiment (5106 pol. protons/cycle). N. Tyurin, Director's session

9. Summary • IHEP has rich experimental program • Single spin asymmetry in different channels (PROZA and FODS experiment) • New polarization program: • FODS-2 will measure spin effects and correlations in the charge pair hadron inclusive production to study transversity. • New SPASCHARM experiment will measure asymmetry in miscellaneous exclusive and inclusive channels including charm and DY production. • We are working to accelerate polarized protons (together with BINP, Novosibirsk). • Intermediate (40-70 GeV) beam energy is a perfect tool to study polarization effects in miscellaneous reactions N. Tyurin, Director's session

10. Backup slides N. Tyurin, Director's session

11. Polarization (asymmetry) in the charge exchange reactions (PROZA:1978-1988) π-p↑→π0n,V.D. Apokin et al., Yad.Fiz.45:1355,1987 π-p↑→n,V.D. Apokin et al., Z.Phys.C35:173,1987. π-p↑→(783)n,I.A. Avvakumov et al.Yad.Fiz.42:1146,1985 π-p↑→f2(1270)n,V.D. Apokin et al.Yad.Fiz.47:727-730,1988] N. Tyurin, Director's session

12. Asymmetry in inclusive π0 production (PROZA-2:1988-2008) pp↑→π0X, Phys.At.Nucl, 67 (2004) 1487 π-p↑→π0X, Phys.At.Nucl, 67 (2004) 1495 Preliminary, 2008 result π-p↑→π0X,Phys.Lett.B243,461 (1990) pp↑→π0X,Presented SPIN2008 first time N. Tyurin, Director's session

13. Asymmetry in charge hadron production (FODS:1993-2008) N. Tyurin, Director's session

14. FODS-2 asymmetry measurements in inclusive charge hadron production • Experimental setup to measure charge hadrons at different angles • Polarized beam from Λ-decays • Asymmetry measurements for π,K,p: • |xF|0.2, 0.5рT4 GeV/c, CM86o • -0.1xF0.7; 0.3рT2.0 GeV/c, 1CM 48o; 2CM105o N. Tyurin, Director's session

15. FODS-2 main results N. Tyurin, Director's session