Decay properties of D and D s mesons Bhavin Patel Department of Physics Sardar Patel University Vallabh Vidyanagar , Gujarat, INDIA

Outline…  Introduction.  Spectroscopic Properties of Light Heavy Flavour Mesons in Coulomb plus Power Potential.  Decay Properties of the Open Heavy Flavour Mesons.  Conclusion.

Open charm D sJ (2632) (Selex) D sJ * (2715) (Belle) D sJ (2860) (Babar) D sJ * (2317) - J P =0 + - cs ~ 2.48 GeV -  < 4.6 MeV D sJ (2460) - J P =1 + - cs ~ 2.55 GeV -  < 5.5 MeV D 0 * (2308) - J P =0 + - P cn ~ 2.46 GeV -  ~ 276 MeV Charmonium X (3872) - J PC =1 ++ (2 –+ ) - cc ~ GeV -  < 2.3 MeV Y(4260) : ?? Y(4385) : 4 3 S 1,3 3 D 1 X (3940) Y (3940):2 3 P J=1,2,3 Z (3940) Light - heavy mesons sector Charmonia sector Open-charm and charmonium like states

Radial wave functions of meson at CPP v =0.8

Effective quark mass

Conclusion  Present study suggests the potential scheme for the description of Open charm flavour mesons as Coulomb plus power potential.  Our model contains few parameters compared to many other models.  The study demonstrates the success of a nonrelativistic potential model in the description of the masses and decay properties of open charm mesons.  We hope that many of the prediction of the model would be supported experimentally in near future at different heavy flavour production, high luminosity experiments.

Thanks

Prof. P C Vinodkumar Dr. J N Pandya (MSU,Vadodara), Dr. Ajay Kumar Rai (SVNIT, Surat), Dr. C J Clement (St. Xavier Sci. College, Ahmedabad), Dr. R H Parmar (Modasa Sci. College, Modasa), Mr. Ajay Majethiya (KITRC, Kalol), Ms. Shereena Joseph (Delhi), Mr. Arpit Parmar and Mr. Kaushal Thakkar. Part of this work is done with a financial support from DST, New Delhi, under a Major Research Project SR/S2-HEP-20/2006.

Backup Slide

 There is a flood of experimental data from high energy experiments from different hadron colliders [BaBar, CDF, CLEO, DELPHI, BELLE,SELEX etc.] in the spectroscopy of heavy flavour hadrons.  Though much of the data are related to mesons, there exists interesting observations related to the heavy flavour baryons.  Baryons themselves are interesting as they represent simple three body systems. Its treatment is complicated compared to the two body meson systems.  Due to disparities among the model predictions of the static properties of baryons and their magnetic moments at the heavy flavour sector [P. Avery et.al(1995)], alternate schemes to describe the properties of baryons particularly in the heavy flavour sector are of recent interest [D. Ebert et.al, (2005)].  For the present study, we employ the hypercentral description of the three-body problem [M. M. Giannini et. al (2001), E. Santopinto et. al, (1998)] for the baryons constituting one or more charm and beauty quarks.

Introduction

New experimental results on charm meson resonances BABAR announced a discovery of new narrow state ; this was confirmed by FOCUS and CLEO ; CLEO also observed narrow state ; Belle found both states and also provided first evidence for two new, broad states both ca MeV higher above the usual and with opposite parity; finally SELEX has announced a new surprisingly narrow state with spin-parity assignment ; there is a proposal to consider it as a first radial excitation of Both have already been proposed as of thespin doublet chiral partners of the heavy-light pseudoscalar and and vector Ds mesons. The states have been proposed to be chiral partners of the D-meson doublet.

D SJ * (2317) BaBar: PRL 90, (2003) Narrow peak in D S  0. J P =0 + I=0 favored. Width consistent with the detector resolution, less than 10 MeV. Mass near 2317 MeV, 40 MeV below DK threshold.

D SJ (2460) Narrow peak in D * S  0, and also observed in D S . J P =1 + favored. Width consistent with the detector resolution, less than 8 MeV. Mass close to 2460 MeV, below D * K threshold. CLEO: PRD 68, (2003)

More than 30 years after the so-called November revolution, heavy meson spectrocospy is being again a challenge. The formerly comfortable world of heavy meson spectroscopy is being severely tested by new experiments The area that is phenomenologically understood extends to: Heavy-light mesons, states where the quark-antiquark pair is in relative S wave; Heavy-heavy meson: states below the DD (BB) threshold In the positive parity sector (P wave, L=1) a number of states have been discovered with masses and widths much different than expected from quark potential models. Open charm D sJ (2632) (Selex) D sJ * (2715) (Belle) D sJ (2860) (Babar) D sJ * (2317) - J P =0 + - P cs ~ 2.48 GeV -  < 4.6 MeV D sJ (2460) - J P =1 + - P cs ~ 2.55 GeV -  < 5.5 MeV D 0 * (2308) - J P =0 + - P cn ~ 2.46 GeV -  ~ 276 MeV Charmonium X (3872) - J PC =1 ++ (2 –+ ) - P cc ~ GeV -  < 2.3 MeV Y(4260) : ?? Y(4385) : 4 3 S 1,3 3 D 1 X (3940) Y (3940):2 3 P J=1,2,3 Z (3940) Heavy-light mesons (QCD hydrogren)Heavy-heavy mesons – – New open-charm and charmonium like states