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Gluonic excitations in the Charmonium region Hirschegg’07 Dynamic and structure of hadrons January 16 th , 2007. Felipe J. Llanes-Estrada Univ. Complutense Madrid. 1. Hadron structure is filtered. q, g ( a s , m q ). Confinement. p, r, h ... (M h , f h , l i ...).
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Gluonic excitations in the Charmonium region Hirschegg’07 Dynamic and structure of hadrons January 16th, 2007 Felipe J. Llanes-Estrada Univ. Complutense Madrid 1
Hadron structure is filtered q, g (as, mq) Confinement p, r, h ... (Mh, fh, li ...) Can peep through with 1) Hard probes 2) Flavor symmetries 3) JPC exotica 4) Detailed branchings Heavy quarkonium above threshold, p-distribution of open flavor decays 2
Fock space expansion Collaborators: S. Cotanch, E. Swanson, A. Szczepaniak, I. General, Ping Wang, P. Bicudo 3
qq qqg qqqq gg ggg qq X - - qqg - X - - qqqq - - X gg - X - ggg - X Exotic channel JPC=1- + 4
Trigonometric or hyperbolic Bogoliubov rotation generates a quasiparticle mass gap 6
Model Hamiltonian: Treat physical gluon exchange in perturbation theory Take V as a classical Cornell potential between charge densities 7
IR Behavior of a connected, fully amputated Yang-Mills Green’s function in Landau gauge with 2n ghost and m gluon legs Alkofer, Fischer, Llanes-Estrada, PLB05 10
Spectrum In quark sector Llanes-Estrada,Szczepaniak,Swanson, Cotanch, PRC04 11
Glueish mesons in the 4-5 GeV region 1) High-pitch glueballs 2) Oddballs 3) Hybrid mesons Confused with: some conventional cc And a multitude of 4+q states 12
y(4260) y(4320) 13
14 Resonances above open charm threshold
Gamow resonances? DD p-wave r(cc) 15
“String breaking” in lattice computations SESAME Collaboration G. Bali et al prd2005 16
Distinguish the wavefunctions Franck-Condon principle (1925) Molecular transitions between two adiabatic levels: nuclei are not affected by the fast electronic jump. 17
Consider relative momentum distribution of DD subsystem in DDp final state 19
22 The hybrid p distribution has no shoulders
To test the idea with a sharper signal: Belle run at the Y(5S) Look at the momentum distribution of BB in the BBp final state. Search for a new vector state in Ypp (to have a supernumerary matching the 4260) between the 4S and 5S. (W.S. Hou) 23
s1 s3 L13 s2 s4 L24 L12-34 sd q q jd q 1 3 q S sd q q 2 4 jd q J L13+L24 +L12-34 S+L12-34 P = (-1) C = (-1) 24
GROUND STATE S-waves only : 0 P-wave: 1 (0 1 2 3) (0 1 2) (with various multiplicities) Rich spectrum “state inflation” hopefully most are too broad. 25
Badalyan (1987; Dafne 1991 LNF-91/017 (R)) Jaffe (1977) M (4 light q´s) = 1565 1450 MeV M (2 light 2 s) = 1950 1800 MeV M (4 s q´s) = 2260 2150 MeV JPC = 1states (Mulders, Aerts, de Swart) 1500,1660,1830,1860,1940,2000,2070,2140, 2210... P-wave exotica 1 from 1700 26
Wang, General, Cotanch,FLE upcoming 1)Molecules are lighter (in agreement with Isgur and Weinstein) 2)About every other new state has a match 3)1-+ in the 1.3-1.4GeV ballpark (hybrids well above 2GeV) 27
In the cm frame of a hybrid, momenta and stresses lie instantaneously in a plane 28
Consider pure four-body (rare strong) decays (p1xp2).p3 Area of faces Choose any 3 mesons p1+p2+p3+p4=0 (center of mom.) 30
Observable: off-planes: ((p1xp2).p3)2 P= (|p1xp2| |p2xp3| |p1xp3| |p1xp4| |p2xp4| |p3xp4|)1/2 1)Dimensionless 2)Permutation invariant (1,2,3,4) in the cm frame 31
For a hybrid For a 4q Internal distribution of off-planes # counts P 32
Maximum: 0.707 P=0.59 (1,2,3) cube 33
To distinguish charmonium from cscs tetraquark 34
Counting rules for inclusive production in e-e+ collider Limit of the cross section as x 1 x= Ey(4260)/Ebeam cc: (1-x) ccg: (1-x)3 J.Gunion PLB79 x 1 35
Counting rules for exclusive double charmonium production Bodwin, Lee and Braaten prl2003 e-e+J/y y(4260) r = 2mc/Ebeam Fixed angle production when r 0 ds/dxconstant for cc r2 for ccg 36
0++ L=0 1++ 2++ 0 L=1 2 3 YLm <s1 m1 s2 m2 | S mS> Coulomb gauge BCS-TDA glueballs (A. Szczepaniak et al. PRL 76, 2011 (1996), F. Llanes-Estrada et al. NPA (2002).) 37
GLUEBALLS (Lattice spectrum from Morningstar and Peardon) 38
Glueballs fall on Regge Trajectories * Interaction between color densities as suggested by QCD in the Coulomb gauge (non abelian gluon-gluon interaction) * Slope of Regge trajectories much smaller than for quark mesons because color factor 3 instead of 4/3 * In (L,S) notation: model (0,0) 0, (2,0) 2, (4,0) 4++ fall on Regge trajectory parallel to pomeron. * The 2 (0,2) falls on Pomeron Regge trajectory, within lattice error bands. * These are little sensitive to spin-orbit coupling which is the model’s largest weakness. 39
F.J.L.E. et al. 2000 40
Glueball decay width Previous estimates: O(10-30) MeV Carlson et al OZI O(150) MeV Bicudo, Abreu string O(400) MeV Cotanch, Williams VMD Our new evaluation: Bicudo, Cotanch, Ll-E, Robertson 2006 43
47 Motivation: new BES state f0(1810) (600,1370,1500,1710,1790) J/ Angular analysis shows quant. numbers 0++ Threshold cusp? No. Tail of the f0(1710)? Adjust for phase space and still off-threshold 44
Prefered decay modes: open flavor • For C=+ charmonia this is an experimental fact • For glueballs it is expected on the basis of string breaking • For radiative J/y decays... as much as a glueball in the middle 50
53 In the end, glueballs are not so broad... Many dynamical effects dispell the legend of the flavor-blind glueball decays