1 / 14

Status of Exotic Meson Searches

Status of Exotic Meson Searches. Spin exotics and glueballs essential to our understanding of QCD. Limit comments to new results or new experiments. WA102, Crystal Barrel, E852, CLAS, GlueX, Compass. Lattice QCD mass predictions. Scalar glueball at about 1.6 GeV. Tensor at 2.3 GeV.

ishmael-dawson
Download Presentation

Status of Exotic Meson Searches

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. Status of Exotic Meson Searches • Spin exotics and glueballs essential to our understanding of QCD. • Limit comments to new results or new experiments. • WA102, Crystal Barrel, E852, CLAS, GlueX, Compass

  2. Lattice QCD mass predictions • Scalar glueball at about 1.6 GeV. • Tensor at 2.3 GeV. • Hybrid spin-exotics start at about 1.9 GeV (Jpc=1-+). • Reviewed by McNeile, hep-lat/0207001 (2002)

  3. Glueball searches - 4p decay • CERN WA102 (central production) • pp4p pp PWA • f0(1370); rr dominant • f0(1500); rr and ss • f0(2000); rr dominant • Barberis et al., PL B471, • 440 (2000) M4p

  4. Glueball searches - 4p decay • CRYSTAL BARREL • important disagreement with WA102 • Abele, et al., Eur. Phys. J. C21, 261 (2001). • Future: r, h’

  5. Hybrid searches • BNL E852 • p-pMp • previous: p1(1400), p1(1600)r • recent: p1(1600)h’- • Ivanov, et al., PRL 86, 3977 (2001)

  6. E852 partial wave fits • p1(1600)h’- dominant! • M=1.60 GeV, G=0.34 GeV • Future: • b1p • f1p • K1K • K*K • p a2 p1

  7. E852 - preliminary 1-+ b1p S intensity • p0p- PWA • large b1p width for p1 • hybrid meson? 4++ r D 1-4 1.6 2.0 2.4 M (GeV)

  8. New experiments • Jefferson Lab. CLAS • gpMp with M3p, KKp • tagged Eg  5.2 GeV Motivation: “vector meson” probe. Good acceptance for few-body decays.

  9. CLAS preliminary 400k events • Large production rates • Search: • isovector 1-+, 3-+ • isoscalar 2+-, 4+- • SLAC 1.8 GeV bump • Condo, et al., PRD 43, • 2787 (1991)  a2  0.8 1.2 1.6 2.0 M3p

  10. JLAB GlueX proposal • New facility - big part of lab upgrade • polarized high-flux beam (Eg = 9 GeV) • dedicated spectrometer

  11. CERN COMPASS • Broad program at SPS • beam on target!

  12. CERN COMPASS • Meson program: • pp central production • pg Primakoff by pA interactions • pP diffraction • L. Schmitt, Proceedings of XXXVII Int. Winter Meeting on Nucl. Phys., Bornio, 1999

  13. COMPASS Primakoff • Expect 106 measured p1 decays. • Moinester and Chung, hep-ex/0003008 (2000)

  14. Summary of glueballs and exotics • WA102, Crystal Barrel, E852 and earlier exps. have written a few chapters of a long story. • By the next ICHEP meeting we can expect even bigger gains. • We need the new experiments to fill in most of the book.

More Related