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New Particles at BELLE Beauty 2005 Assisi Spectroscopy and new Particles F. Mandl There is an impressive list of new particles in the charm sector discovered by BELLE in the last few years: This talk covers only Not included in this talk X(3872) c (3753) Phys. Rev. Lett. 89 (2002) X(3940) (2308) Y(3940) Phys. Rev. Lett. 94 (2005) D 1 (2427) c (2800) Phys. Rev. Lett. 94 (2005) Phys. Rev. D 69 (2004)

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Beauty 2005 Assisi Spectroscopy and new Particles F. Mandl

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Discovery of X(3872) J/ History Discovery by BELLE : narrow J mass peak in excl. B K J decays Phys. Rev. Lett. 91, 262001 (2003) has been confirmed by CDF II, D0, BaBar m, not compatible with charmonium state m peaks near upper kinematic limit as expected for but : charmonium decaying to J/ violates isospin suppressed

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Beauty 2005 Assisi Spectroscopy and new Particles F. Mandl X(3872) observation

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Beauty 2005 Assisi Spectroscopy and new Particles F. Mandl Theoretical Explanation for X(3872) What could it be? M x = (3871.9 ± 0.5) MeV is within error equal to the threshold (3871.3 ± 1) MeV Speculation: X might be a molecule - like bound state Tornquist: J PC = 0 -+, 1 ++ C = +1 J via 0 J/ intermediate state m concentrated at high masses Swanson: dynamical model for X as a hadronic resonance J PC = 1 ++ strongly favoured + appreciable admixture of J/ + small J/ Decay X(3872) J/ observation would unambiguously establish C = 1 for X

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Beauty 2005 Assisi Spectroscopy and new Particles F. Mandl Study of X(3872) J/ Study B K J/ 256 fb -1 data sample (275 M ) Selection: J/ , K 0 or K , P tab > 40 MeV to reduce continuum events (e + e - q b) R2 < 0.4 (normalized Fox-Wolfram moment) |cos B | < 0.8 B polar angle of B in cms B K J/ are identified by

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Beauty 2005 Assisi Spectroscopy and new Particles F. Mandl Evidence for X(3872) J/ Constraint: Signal Region: M bc > 5.20 GeV 5.2745 < M bc < 5.2855 GeV | E| < 0.2 GeV | E| < 0.035 GeV Prominent peak near 3510 MeV in M( J/ ) is used for calibration The only significant B-meson signal is in the 3872 MeV bin (also for E-distribution) Simultaneous fit of M bc and E and background (ARGUS function for M bc and first order polynominal for E): Signal yield: 13.6 ± 4.4 events, Significance: 4.0

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Beauty 2005 Assisi Spectroscopy and new Particles F. Mandl

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Evidence for X(3872) J/ X J/ similar selection as above slightly different signal region only significant B-meson signal in 3872 MeV bin (not shown) M bc distribution for various inv. mass bins: only significant B meson signal for M( ) > 750 MeV bin the same for E Fit: 12.4 ± 4.1 events Significance: 4.3 possible background B K J/ fit: 0.75 ± 0.14 events B K J/ non res., use left and right side bound region 1.3 ± 1.0 events

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X(3872) + J/ A ~ J/ x p rel p waves L int 1-p = 4%, 0.01% Transversity analysis useful for decays to V + V triple scalar product rest frame J/ in rest frame

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Beauty 2005 Assisi Spectroscopy and new Particles F. Mandl X(3872) + J/ A ~ J/ L int 1-p = 0.3%, 5x10 -6 % common rest frame of J/ and 0 (relativ momentum maybe neglected)

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Beauty 2005 Assisi Spectroscopy and new Particles F. Mandl X(3872) + J/ A ~ x J/ L int 1-p = 75%, 16% triple scalar product in X rest frame (D = 0) neglecting rel.mom. between J/ and 0 : all are in same CMS

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Beauty 2005 Assisi Spectroscopy and new Particles F. Mandl X(3872) + J/ centrifugal barrier !

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Beauty 2005 Assisi Spectroscopy and new Particles F. Mandl 3 pseudoscalars require D-wave

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Beauty 2005 Assisi Spectroscopy and new Particles F. Mandl I-violating hadr.trans.: (2S) J/

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Beauty 2005 Assisi Spectroscopy and new Particles F. Mandl X(3940) Further analysis of the processes History: first observation of such processes by BELLE Phys. Rev. Lett. 89, 142001 (2002) Theoretical calculation: various speculations: glueball contribution ? etc. For the first time seen: X(3940) new charmonium state Look for recoil to J/ and (2S) etc.

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double charmonium Beauty 2005 Assisi Spectroscopy and new Particles F. Mandl Study of the decay of reconstructed (2S) J/ search for look for recoil spectra 3 significant signals seen: (BaBar gets consistent results)

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e + e - J/ X Beauty 2005 Assisi Spectroscopy and new Particles F. Mandl Using higher statistics (287 fb ) extend analysis of recoil masses against J/ above DD threshold find new significant peak at M ~ 3.940 GeV/c 2 “X(3940)” Fit: c, co, c (2S), X(3940) + background M X = (3.937 ± 0.012) GeV/c 2 compatible with 0 (< 95 MeV/c 2 ) 90% CL <~ resolution (=32 MeV) no signal of X(3872)

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Beauty 2005 Assisi Spectroscopy and new Particles F. Mandl

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≠ X(3940)

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Beauty 2005 Assisi Spectroscopy and new Particles F. Mandl Charmed baryon spectroscopy light diquark in the environment of a heavy quark test for theoretical models PDG 2004: 4 excited charmed baryons observed c (2455) ground state c (2520) Aim : find excitations of c Analysis: uses data sample 253 fb -1 at (4S), signal window around : ± 8 MeV/c 2 x p > 0.5 for candidates yield: (516 ± 2) x 10 13 S/B = 2.3 combine with x p > 0.7 cos dec > -0.4 dec = angle between ( in rest frame of ) and boost direction of the system in cms

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Beauty 2005 Assisi Spectroscopy and new Particles F. Mandl (0) (+) (++)

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Beauty 2005 Assisi Spectroscopy and new Particles F. Mandl Charmed baryon spectroscopy c (2800) 0 c (2800) + c (2800) ++ Isotriplet Enhancement at M ~ 0.43 GeV for M( ) and M( + ) feed-down from decay c (2880)+ + observed by CLEO next: study + : clear peaks of c (2800) + and c (2765) + seen consistent with observation of CLEO Fit: Isotriplet + feed-down + combinatorial background (e + e - c (2800)X) x Br( c (2800) ) 2.04 (0), 2.6 (+), 2.36 (++) pb Theoretical models c2 doublet with J p = 3/2 - and 5/2 - c2 mainly in D wave M = 500 MeV/c 2 as measured ~ 15 MeV smaller as measured c2 (J P = 3/2 - ) can mix with c1 (J P = 3/2 - ) and would produce a wider physical state

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Beauty 2005 Assisi Spectroscopy and new Particles F. Mandl Summary c (2800) triplet established X(3940) new charmonium state tentative identification: c2, J P = 3/2 - ; c1, J P = 3/2 - admixture seen for the first time (now also BaBar)

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Beauty 2005 Assisi Spectroscopy and new Particles F. Mandl SPARES

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Continuum Suppression e+e+ e-e- e+e+ e-e- qq Signal B Other B Unwanted Background for B-Decays: Continuum Jet-like BB spheric e + e qq “continuum” (~3x BB) To suppress: use event shape variables continuum Y (4S) Beauty 2005 Assisi Spectroscopy and new Particles F. Mandl

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Continuum Suppression To separate spherical BB events from jet-like continuum events, topological variables are used: 1)Second Fox-Wolfram moment 2)Super Fox-Wolfram (six modified Fox-Wolfram moments, Fisher discriminant) 3) Angle between B meson and beam axis direction 4) Angle between thrusts of selected B meson particles and all other particles in event Likelihood ratio includes all info. Beauty 2005 Assisi Spectroscopy and new Particles F. Mandl

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J PC possibilities for X(3872) J ≤ 2 DD allowed & P- violating unlikely signal for X γJ/ψ C=-1 ruled out check of angular distributions rules out 1 ±-,0 ±+,2 -- fits of M ππ 2 -+ unlikely X(3872) = χ c1 ‘? unlikely, since mass and BR ratio way off theo. expect.

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