1 / 9

Spin Physics with Antiprotons

FNAL Antiproton Accumulator • world record p stacking rate ( ≈ 2 ×10 11 /hr ) • jet target experiments E760/E835 (<2000) L ≈ 2 ×10 31 cm - 2 s - 1 ( → 2 ×10 32 cm -2 s -1 ) • Precision QCD tests and spectroscopy • Physics of Flavour Studies

kordell
Download Presentation

Spin Physics with Antiprotons

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. FNAL Antiproton Accumulator • world record pstacking rate (≈ 2 ×1011/hr) • jet target experiments E760/E835 (<2000) L ≈ 2 ×1031cm-2 s-1 (→ 2 ×1032cm-2 s-1 ) • PrecisionQCDtests and spectroscopy • Physics ofFlavourStudies • Studies of basic symmetries (CP, CPT) • Spindependence  Polarized { gas target p beam (!?) (In collaboration with Y.Onel et al., U.of Iowa) Aldo Penzo Project X WorkshopINFN-Trieste Istituto Nazionale di Fisica Nucleare INFN Fermilab, Nov. 07 Sezione di Trieste Spin Physics with Antiprotons

  2. QCD tests Flavour, pp → LL Symmetries Spectroscopy p↑p↑→ l+ l- X (Drell-Yan) Transversity New Physics ? Spin Physics with p(Some References) • S. Brodsky -Testing QCD in Antiproton Reactions, SLAC-PUB-4451 (Oct 1987) • J-M. Richard -Spin and Flavour, arXiv:nucl-th/9302003v1 (Feb 1993) - Antiproton induced reactions, arXiv:nucl-th/9406025v2 (Jul 1994) • W.A. Mok, K.J. Sebastian -Charmonium states in polarized p-pbar collisions, N. Cim. A110, 429 (1997) • V. Barone, A. Drago and P. Ratcliffe – Phys. Rep. 359, 1 (2002) • M.Anselmino et al. - Phys.Lett. B594, 97 (2004) • R. Jaffe -Open questions in high-energy spin physics, MIT-CTP-3230 (Jan 2002) • J. Ellis -Polarization puts a New Spin on Physics, arXiv:hep-ph/0701049v1 (Jan 2007)

  3. (Polarized) gas target in p Accumulator • 8 GeV p in AP2 line • 120 GeV p (8x1012) on target • Target Density Thickness Luminosity < P > Type [at./cm3] [cm; at./cm2] [cm-2 s-1] • Mol. Cluster 4x1014 0.7; 3x1014 2x1032 0.0 • Atomic Beam 6x10111.0; 6x10114x1029 0.9 • Storage Cell 5x1012 20.; 1x10147x1031 0.8

  4. Polarized target – single spin AN measurements - spin correlations in pp → LL -q – qannihilation in⇈/⇅spin states Impressive effort (PAX at FAIR, GSI) for pol. p : huge investment (>102 M€ ), long-range project (> 2014) Polarized antiprotons? ... WHY? • Sharper spectroscopy selection rules • Stronger QCD tests • Nucleon transversity via Drell-Yan:p↑p↑→ l+ l- X Many theory/phenomenology papers, see: S. Brodsky, E. Leader, J. Ellis, J-M. Richard, …

  5. Experimental proof Technical tests AHWD:p → (Lo) → p↑ (2 x 105 p↑/ 1012 prim. p) APES:p → p (p) → p↑(p) (2 x 103 p↑/ 1012 prim. p) Polarized Antiprotons: HOW? Workshop on Polarized Antiproton Sources Bodega Bay CA, April 1985; O. Chamberlain, A. Krisch, A. Lin • Antihyperon Decay • Spin Filter • Stochastic Tecniques • Dynamic Nuclear Polarization • Syncrotron Radiation emission • Antiproton Scattering • Repeated Stern-Gerlach • Antihydrogen formation • Penning trap • Channeling • ...........??? Workshop (29-31 Aug 2007) at Cockcroft Institute, Daresbury Lab, UK (mainly spin filter)

  6. p/p <P> More speculative methods to produce p↑: • Spin filter:differential absorption of p spin states (IF s⇈≠s⇅); polarized storage cell • Spin splitter:Stern–Gerlach separation of p spin states; spin rotator+2 quadrupoles SF tested with protons (P ~ 0.04, I/Io ~ 0.1); but p ??? If SS tested with protons, p OK FM = I*P2 AHWD vs APES • p → p 2x10-5 0.0 • p → (Lo) → p↑ 2x10-7 ~ 0.45 • p → p (p) → p↑(p) 4x10-9 ~ 0.30 Spin Filter – Spin Splitter Spin Filter – baseline for GSI

  7. Prospects for p spin physics Medium term: • FNAL Antiproton Source survive collider era: • Challenging, fresh physics! • Moderate cost upgrades? • Polarized gas target to complement E835 jet • AHWD secondary beam (~ 8 GeV) from Main Injector (40 GeV) to antiproton accumulator? Longer term: • Tests of Spin Filter/Splitter in Accumulator Ring (+ gas target)

  8. g* q e+ s q g e- q s q dADY ≈ ± 0.10 (T= 107 s) dALL ≈ ± 0.04 (T= 107 s) From MI (40GeV) to p accumulator (8GeV)+(pol.)H target [L ≈ 1014x1010x6.105 ≈ 6x1029 cm-2 s-1, PB ≈ 0.45, PT ≈0.8] Benchmark processes <sA> ≈ 10-34 cm2 (4 ≤ M ≤ 9 GeV) <sA> ≈ 10-30 cm2

  9. Back-up slide Throw in numbers… Consider p → (Lo) → p↑in 2 cases: - From MI (40GeV) to p accumulator (8GeV)+(pol.)H gas target [L ≈ 1014x1010x6.105 ≈ 6x1029 cm-2 s-1, PB ≈ 0.45, PT ≈0.8] - From SY (120 GeV) to sec. line (30GeV p)+pol. target (NH3) [L ≈ 2x106x3x6x1023 ≈ 6x1030 cm-2 s-1, PB ≈ 0.45, PT ≈0.2] Asymmetry error is dA ≈ 1/(PB PTNev) For p↑p↑→ l+ l- X (D-Y), <sA> ≈ 10-34 cm2 (4 ≤ M ≤ 9 GeV) In a period of 107 s, dADY ≈ 1/(0.45x0.8x25) ≈ ± 0.10 and dADY ≈ 1/(0.45x0.2x77) ≈ ± 0.14 for the 2 cases respectively. For p↑p↑→ LoLo X,<sA> ≈ 10-30 cm2 ; in a period of 105 s dALL ≈ 1/(0.45x0.8x230) ≈ ± 0.01 and dALL ≈ ± 0.02. If the hyperons’ spin are analyzed, dCLL ≈ 1/(0.45x0.2x0.36x230) ≈ ± 0.04, and the same for the second case. … close to ballpark…?! Back-up slide

More Related