& & #!" # BABAR $ % Belle Conversano - 15 June 03

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1 & & # ' (!" # BABAR $ % Belle QC@Work Converano - 15 June 3

2 Outline c )) & '# )', - "#'(" '&, " (/) ' %( (&, "."##("

3 Spectrocopy of c tate Potential model of [heavy-quark light-quark] meon have had o far reaonable ucce in decribing the pectrocopy of the,, B, B ytem S. Godfrey and N. Igur, Phy. Rev. 3, 189 (1985); S. Godfrey and R. Kokoki, Phy. Rev. 43, 1679 (1991), M. i Pierro and E. Eichten, Phy. Rev. 64, 1144 (1) 1 S 1 1 S S S1 S-wave 1 3 P (.48) 1(,"#( 1 1 P 1 (.53) 3 3 (94%), (6%) P-wave 3 1 P P iopin-violating J #3 [narrow] (573) 1 (535) Limited experimental information (11) = 3 [narrow] (1969) J = j S, j = L j heavy S light doublet j =1 doublet Predicted ma range:.4.6 GeV c Predicted large width range : (for decay by K-emiion) 7 99 MeV NO experim. candidate (o far) IF their mae were below () K threhold, they would decay by iopin-violating -emiion and would be extremely narrow! The reult preented here concern tate [,1 ], below K, K threhold, decaying to,!

4 Charm B-factorie e e - Y(4S) Beam ata taking CESR (Cornell) Symmetric PEP-II (SLAC) Aymmetric Start: 1999 KEK-B (Tukuba) Aymmetric Start: 1999 et./expt. CLEO-II Belle Ldt 13.5 fb [] Integrated Luminoity relative to the data ample ued for the reult preented here [] 91.5 fb 86.9 fb The Y(4S) reonance lay on a large continuum bkgd : Effective cro ection at the energy of the Y(4S) 4 e e - bb cc uu dd τ τ - µ µ - e e - σ (nb) Powerful tool for charm phyic

5 Charm Phyic from Continuum Production By uing incluive continuum event combinatorial bkg i trongly reduced! N( )/εn/. GeV/c.3. BABAR Entrie / MeV/c 1 75 BABAR φ φ S p, GeV/c Solid (open) point: on (off) reonance data [normalized] M(φ), GeV/c Kinematical election: require cut on CMS momentum of charmed meon : p >. 5GeV c 5 It can be increaed for cleaner ample (if tatitic allow)

6 Recontruction Method & Selection Criteria (from ) ',4" " #)( ; K K, K K ; PI geometric fit at a common vertex : P( χ ) >.1% E > 1MeV not haring photon with other conitent with production at the interaction region NOT IN SCALE p >. 5 GeV c (or tighter) couple (origin in track vertex) with kinematic fit [contraint : m( )] : P( χ ) > 1% couple (origin in production vertex) with kinematic fit [contraint : m( )] : ( ) > 1% 6 P χ

7 Further background rejection Select quai-two body decay mode [ φ, K K ] dijoint ub-ample Helicity angle cut [ -body decay of ] ( φ, K ) co ϑ >.5 7

Ma Spectra : K K,, K K, couple in event with candidate Broad peak due to random combination (11) where (11)!! A ignal @.

8 Ma Spectra : K K,, K K, couple in event with candidate Broad peak due to random combination (11) where (11)!! A GeVc i miing in ideband dit n : the peak i aociated to the ytem! : kinematic fit E( ): ma contraint No other ignal i evident up to.7 GeVc a part that aociated with (11) 8

9 ma pectra and fit [ hep-ex/341, 1 PRL] K K p > 3. 5 GeV c < m > = ±.4 ( tat.) MeV c Γ = 8.6 ±.4 ( tat.) MeV c Ma ytematic uncertainty etimated conervatively to be < 3 MeV/c 167 ± 53 candidate J (317) An etimate of the ma reolution for the ytem K K - can be provided directly from the data by fitting the ma dit n for characterized by a width conitent with that of the oberved ignal. A imilar ma reolution can be obtained from the imulation of K K J (317) [ Γ ] 73 ± 33 candidate < m > = ± 1.3 ( tat.) MeV c Γ = 8.8 ± 1.1( tat.) MeV c K K p( ) > 3MeV 9 c Oberved width conitent with expt. reolution Intrinic width i maller (Γ<1MeV/c )[I-violation]

10 J (317) ecay Angular it n ϑ : angle in the ret frame w.r.t the (317) flight direction in the CMS J J (317) within bin of [BKG ubtracted] coϑ arb. unit Efficiency arb. unit Angular dit n conitent with being flat ( 43% probability ) Thi would be expected for: a pin J= tate a higher-pin tate produced unpolarized 1

Tet for Reflection J (317) e e cc NO ignal found uing imulation of all known charmed tate and decay NO J (317) ignal found when exchanging -K identification hypothee [no,, een] evt/7mev/c Invetigated

11 Tet for Reflection J (317) e e cc NO ignal found uing imulation of all known charmed tate and decay NO J (317) ignal found when exchanging -K identification hypothee [no,, een] evt/7mev/c Invetigated decay involving known particle and generating a ignal through the additionomiionubtitution of a or a. Nothing found! However... J (317) m( )[ GeV c ] 11 p ( ) > 3. 5 GeV? Combination Combination c CHECK [MC UNFOLING] : thi feed down 1) would have a width Γ=15MeVc (meared peak!) ) can explain only 1/6 of the oberved GeV/c J (317) I thi a new narrow tate kinematically feeding-down a (317) ignal: J e e X ( 46) X? recoil J (317) lotrandom Thi poible ignal require additional detailed tudy

12 Confirmation of J CLEO II & Belle [ hep-ex/3517 ] 31± 3 m( S m( S ) ) m( S ) ideband ideband 77 ± 43 φ only S < m > = 35.3± 1.( tat.) MeV c Γ = ( tat.) MeV c < m >= 317. ±.5( tat.) MeV c Γ = 8.1±.5( tat.) MeV c Conitent with experimental reolution 1

13 J p =? & Other J (317) ecay Mode For a parity conerving decay to [ - ], only natural pin-parity erie i allowed: J ) =,1 -,, IF J ) = (uggeted by low ma & compatible with helicity dit n) it cannot decay into [, ] wherea e.-m. decay into [1 - ] i allowed (by parity & angular momentum conervation) On the other hand, IF J ) = 1, it could trongly decay into - [I-conerving, OZI-uppreed] IF J ) =, it cannot ( 3peudocalar)! Studied decay mode into: (11),,, [ BABAR & CLEO]; [ CLEO] NO ignificant ignal een within current tatitic p ( ) > 3. 5 GeV c Combination CLEO B.R. [w.r.t ] Upper Limit m [ GeV 13 p ( ) > 3. 5 GeV c ] c Combination Combination MOE 9%C.L. <.54 <.78 <.

14 Theorit ent back to their drawing board [from: SLAC Pre Releae] 1 paper in May 1-! main clae of interpretation : a) Within a quark model repreentation Cahn & Jackon van Beveren & Rupp Bardeen, Eichten & Hill hep-ph/351 hep-ph/3535 hep-ph/3549 [ J Quai-bound (317) till a c tate] Modified potential model in tandard pectrocopy c c in unitarized meon model Chiral Perturbation theory HQET Godfrey Colangelo & e Fazio hep-ph/351 hep-ph/3514 Reviion needed for mae! Crucial i the B.R. for decay Heavy quark pin-flavor ym. Vector Meon om. Anatz b) quark model explanation unlikely: different type of tate (tetraquark) Barne,Cloe & Lipkin Cheng & Hou Szczepaniak Bali hep-ph/355 hep-ph/3538 hep-ph/356 hep-ph/ molecular type 4-quark tate [K molecule] 4-quark tate atom [ c ( nn), n = u, d] Lattice prediction on mae conitent with c quark model

15 X (46) : i it really a new tate? e e cc MC tudie : including m( ) J (317) m( ) random random (317) J random (317) J random m( S ) m( S ) Kinematical CROSS-THROUGH Concern: FEE-UP from J (317) : for ignal band there i a peaking BKG aociated with the croing band produced by J 317) 15 ( Thi can be addreed with different technique! For itance: a) MC-baed unfolding method: feed-up probability & linehape ditortion [CLEO] b) Sideband from data ued to etimate peaking BKG [CLEO & BELLE] will releae reult oon

16 YES! Evidence of a new GeV/c into CLEO BELLE ignal region ignal region ignal region ideband region Feed-up: 9% Lower ideband Upper ideband J (46) Raw yield :131±1 candidate Peaking BKG : 38±8 candidate m( S ) (463) Number of candidate M( ) M( ) [MeV] σ [MeV] Statitical ignificance ~ 5.3σ Sideband ubtraction 4.8 ± ± ± Unfolding method 4.7 ± ± ± 1. Γ 7 MeV c < BKG-ubtracted yield: 93± cand. Statitical ignificance ~ 4.σ m >= 459. ± 1.4( tat.) MeV c Γ 7 MeV c

J tate in excluive decay of B meon [bybelle] 56-78" ominant excluive proce for the two J production in B decay i : B J S CLEO B.R. [w.r.t ] Upper Limit 13fb -1 MOE 9%C.

17 J tate in excluive decay of B meon [bybelle] 56-78" ominant excluive proce for the two J production in B decay i : B J S CLEO B.R. [w.r.t ] Upper Limit 13fb -1 MOE 9%C.L. <.49 <.16 <.8 17 B( B( J (46) ) =.1±.7 ±.3 (46) ) J S S P J (46) S J A preliminary helicity dit n how to be conitent with 1 tate 9fb -1

18 Summary & Concluion Two narrow tate have been oberved, in the incluive & invariant ma ditribution, near.317gevc &.46GeVc. The width [Γ<1MeVc ] are conitent with experimental reolution. The maller intrinic width are due to iopin-violation in their decay. The mot likely aignment for their pin-parity i & 1. They do not fit well into the exiting potential model for c pectrocopy. The ma plitting m[ J (317)]-m[ (1969)] & m[ J (46)]-m[ (11)] are conitent with being equal a predicted by Bardeen et al. (BEH) if thee are & 1 tate. The B.R. Upper Limit for the decay of (317) into, and, [w.r.t. ] and the preliminary B.R. meaurement for the decay of (46) into [w.r.t. ] are conitent with BEH prediction. Mot reult are compatible with model baed on HQET and chiral ymmetry, which predict that & 1 are the chiral partner of the, & 1, tate, with ame ma plitting. Intereting time ahead both for experimentalit & theorit. 18

19 &#"#9 B( J (317) final mode) B( (317) ) J S MOE 9%C.L. <.54 <.78 <. BEH.8 CLEO B( J (46) final mode) B( (46) ) J S MOE 9%C.L. <.49 <.16 <.8 BELLE.1±.7 ±.3 BEH.4..?

Introduction The CLEO detector and Y(5S) data sample Analysis techniques: Exclusive approach Inclusive approach Summary

Introduction The CLEO detector and Y(5S) data ample Analyi technique: Excluive approach Incluive approach Summary Victor Pavlunin Purdue Univerity CLEO collaboration Preented at Firt Meeting of the APS