1,725,461 research outputs found
The possible interpretations of Y(4260)
No full textThe recently observed Y(4260) lies far above the decay threshold with a width less than 100 MeV We argue that it is very difficult to accommodate Y(4260) as a conventional cc radial excitation or a D-wave state. It cannot be a hadronic molecule. Its production mechanism and special decay pattern do not favor the glueball interpretation. If Y(4260) is a scalar tetraquark, it must be produced by the I = 0 component of the virtual photon. Then the I = 1, 1, = 0 component of the virtual photon should have produced its isovector partner Y'(4260), which may be searched for in the decay channel pi (+)pi -pi(0)J/psi using exactly the same database from the initial state radiation process. The observation/non-observation of Y'(4260) can easily confirm/reject the tetraquark hypothesis. However, a tetraquark far above threshold can fall apart into DD, D* D very easily. Its not-so-large width and the non-observation of DD mode tend to disfavor the tetraquark hypothesis. Hence the only feasible interpretation is a hybrid charmonium if Y(4260) is NOT an experimental artifact. At present, none of the experimental information from BaBar measurement is in conflict with the hybrid charmonium picture. (c) 2005 Elsevier B.V. All rights reserved.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000232447300007&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Physics, MultidisciplinarySCI(E)102ARTICLE3-4212-21662
Search for the B→Y(4260)K , Y(4260)→J/ψπ+π− decays
No full textWe report the results of a search for the B→Y(4260)K, Y(4260)→J/ψπ+π- decays. This study is based on a data sample corresponding to an integrated luminosity of 711 fb-1, collected at the (4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. We investigate the J/ψπ+π- invariant mass distribution in the range 4.0 to 4.6 GeV/c2 using both B+→J/ψπ+π-K+ and B0→J/ψπ+π-KS0 decays. We find excesses of events above the background levels, with significances of 2.1 and 0.9 standard deviations for charged and neutral B→Y(4260)K decays, respectively, taking into account the systematic uncertainties. These correspond to upper limits on the product of branching fractions, B(B+→Y(4260)K+)×B(Y(4260)→J/ψπ+π-)<1.4×10-5 and B(B0→Y(4260)K0)×B(Y(4260)→J/ψπ+π-)<1.7×10-5 at the 90% confidence level
Nature of X(4260)
No full textWe study the properties of the X(4260) resonance by reanalyzing all experimental data available, especially the e(+)e(-) -> J/psi pi(+)pi(-), omega chi(c0) cross section data. The final-state interactions of the pi pi, K (K) over bar coupled-channel system are also taken into account. A sizable coupling between X(4260) and omega chi(c0) is found. The inclusion of the omega chi(c0) data indicates a small value of Gamma(e+e-) = 23.30 +/- 3.55 eV.National Natural Science Foundation of China [10925522, 11021092]SCI(E)[email protected]
Probing the nature of Y(4260) in the isospin violating process Y(4260)→J/ψηπ0
Get PDFThe isospin violation process Y(4260)→J/ψηπ0 is studied assuming that Y(4260) is a D1D¯+c.c. hadronic molecule. In association with the production of the Zc(3900), which is treated as a DD¯∗+c.c. hadronic molecule, this process can help us distinguish their molecular natures from other scenarios, since the incomplete cancellation between the charged and neutral--meson loops, which are prominent in the molecular picture only, produces a peak in the e+e−→Y(4260)→J/ψηπ0 cross section at the D1D¯+c.c. threshold and a very prominent peak in the J/ψη invariant mass spectrum in between the DD¯∗+c.c. thresholds; the latter being much narrower than the corresponding one in the isospin conserving channel, i.e. J/ψπ+π−. The partial width of Y(4260)→J/ψηπ0 is about 4×10−4 of that of Y(4260)→J/ψπ+π−. The cross section of e+e−→Y(4260)→J/ψηπ0 at the D1D¯+c.c. threshold is about 0.05 pb which is much larger than that produced by the nearby resonances. These features are the direct consequences of the assumed nature of these two states which might be accessible at the high-statistics experiments such as BESIII and LHCb
Search for the decays
Get PDFInternational audienceWe report the results of a search for the B→Y(4260)K, Y(4260)→J/ψπ+π- decays. This study is based on a data sample corresponding to an integrated luminosity of 711 fb-1, collected at the ϒ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. We investigate the J/ψπ+π- invariant mass distribution in the range 4.0 to 4.6 GeV/c2 using both B+→J/ψπ+π-K+ and B0→J/ψπ+π-KS0 decays. We find excesses of events above the background levels, with significances of 2.1 and 0.9 standard deviations for charged and neutral B→Y(4260)K decays, respectively, taking into account the systematic uncertainties. These correspond to upper limits on the product of branching fractions, B(B+→Y(4260)K+)×B(Y(4260)→J/ψπ+π-)<1.4×10-5 and B(B0→Y(4260)K0)×B(Y(4260)→J/ψπ+π-)<1.7×10-5 at the 90% confidence level
Pionic transition from Y(4260) to Z
No full textWe study the pionic transition from Y(4260) to Z
c(3900), where Y(4260) and Z
c(3900) are regarded as the weakly bound states of D
(2420) + H.c. and D
+ H.c., respectively. The partial width of Y(4260)
Z
c(3900) is estimated to be of the order of MeV with the wave functions of the bound states, where the wave functions are simulated by the simple harmonic oscillator wave functions with equivalent root-mean-square radii
Four quark interpretation of Y(4260)
No full textWe propose that the Y(4260) particle recently announced by BABAR is the first orbital excitation of a diquark-antidiquark state [cs][c* s*]. Using parameters recently determined to describe the X(3872) and X(3940) we show that the Y mass is compatible with the orbital excitation picture. A crucial prediction is that Y(4260) should decay predominantly in DsDs. The Y(4260) should also be seen in B nonleptonic decays in association with one kaon. We consider the full nonet of related four-quark states and their predicted properties. Finally, we comment on a possible narrow resonance in the same channel
Production of the Y(4260) state in B meson decay
No full textAbstractWe calculate the branching ratio for the production of the meson Y(4260) in the decay B−→Y(4260)K−. We use QCD sum rules approach and we consider the Y(4260) to be a mixture between charmonium and exotic tetraquark, [c¯q¯][qc], states with JPC=1−−. Using the value of the mixing angle determined previously as: θ=(53.0±0.5)∘, we get the branching ratio B(B→Y(4260)K)=(1.34±0.47)×10−6, which allows us to estimate an interval on the branching fraction 3.0×10−8<BY<1.8×10−6 in agreement with the experimental upper limit reported by BaBar Collaboration
The Y(4260) as an ωχc1 molecular state
No full textAbstractIt is suggested that the newly observed Y(4260) by BaBar Collaboration is a molecular state composed of an ω and a χc1. Both the production and decay properties are discussed. A consequence for this molecular state, Y(4260), is that it decays into π+π−π0χc1 with similar rate to π+π−J/ψ. It is also expected that Y(4260)→π0π0J/ψ is produced at half rate as Y(4260)→π+π−J/ψ. These decay modes should be searched for in the B factories using initial state radiative return data and B decay data as well
Studies on X(4260) and X(4660) particles
No full textStudies on the X(4260) and X(4660) resonant states in an effective lagrangian approach are reviewed. Using a Breit-Wigner propagator to describe their propagation, we find that the X(4260) has a sizable coupling to the ???c0 channel, while other couplings are found to be negligible. Besides, it couples much stronger to s than to f0(980): |g X????2/g2X??f0(980)| ?? O(10). As an approximate result for X(4660), we obtain that the ratio of Br(X&rarr??c+ ??c- ) Br(X&rarr??(2s)??+ ??-) ??e; 20. Finally, taking X(3872) as an example, we also point out a possible way to extend the previous method to a more general one in the effective lagrangian approach. ? Copyright owned by the author(s).EI
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