21 research outputs found
and
Recently Babar Collaboration reported a new state
and Belle Collaboration observed . We investigate the strong
decays of the excited states using the model. After
comparing the theoretical decay widths and decay patterns with the available
experimental data, we tend to conclude: (1) is probably the
state although the
assignment is not completely excluded; (2) seems unlikely to be
the and candidate; (3)
as either a or state is
consistent with the experimental data; (4) experimental search of
in the channels , , and
will be crucial to distinguish the above two possibilities.Comment: 18 pages, 7 figures, 2 tables. Some discussions added. The final
version to appear at EPJ
The newly observed open-charm states in quark model
Comparing the measured properties of the newly observed open-charm states
D(2550), D(2600), D(2750), D(2760), D_{s1}(2710), D_{sJ}(2860), and
D_{sJ}(3040) with our predicted spectroscopy and strong decays in a constituent
quark model, we find that: (1) the D(2\,^1S_0) assignment to D(2550) remains
open for its too broad width determined by experiment; (2) the D(2600) and
can be identified as the 2\,^3S_1-1\,^3D_1 mixtures; (3) if
the D(2760) and D(2750) are indeed the same resonance, they would be the
D(1\,^3D_3); otherwise, they could be assigned as the D(1\,^3D_3) and
, respectively; (4) the could be either the
's partner or the D_s(1\,^3D_3); and (5) both the
and interpretations for the seem likely. The
and radiative decays of these sates are also studied. Further
experimental efforts are needed to test the present quarkonium assignments for
these new open-charm states.Comment: 26 pages,7 figures, journal versio
On the Mechanism of Open-Flavor Strong Decays
Open-flavor strong decays are mediated by pair production, which is
known to occur dominantly with \3p0 quantum numbers. The relation of the
phenomenological \3p0 model of these decays to ``microscopic" QCD decay
mechanisms has never been clearly established. In this paper we investigate
meson decay amplitudes assuming pair production from the scalar
confining interaction (sKs) and from one gluon exchange (OGE). sKs pair
production predicts decay amplitudes of approximately the correct magnitude and
D/S amplitude ratios in and which are close
to experiment. The OGE decay amplitude is found to be subdominant in most
cases, a notable exception being PSS. The full
sKs~+~OGE amplitudes differ significantly from \3p0 model predictions in some
channels and can be distinguished experimentally, for example through an
accurate comparison of the D/S amplitude ratios in and
.Comment: 44 pages, 22 eps figures, RevTex, complete postscript file available
at http://csep2.phy.ornl.gov/theory_group/people/barnes/pubs/abs.p
Towards resolution of the enigmas of P-wave meson spectroscopy
The mass spectrum of P-wave mesons is considered in a nonrelativistic
constituent quark model. The results show the common mass degeneracy of the
isovector and isodoublet states of the scalar and tensor meson nonets, and do
not exclude the possibility of a similar degeneracy of the same states of the
axial-vector and pseudovector nonets. Current experimental hadronic and \tau
-decay data suggest, however, a different scenario leading to the a_1 meson
mass \simeq 1190 MeV and the K_{1A}-K_{1B} mixing angle \simeq (37\pm 3)^o.
Possible s\bar{s} states of the four nonets are also discussed.Comment: 22 pages, LaTe
Prospects for e+e- physics at Frascati between the phi and the psi
We present a detailed study, done in the framework of the INFN 2006 Roadmap,
of the prospects for e+e- physics at the Frascati National Laboratories. The
physics case for an e+e- collider running at high luminosity at the phi
resonance energy and also reaching a maximum center of mass energy of 2.5 GeV
is discussed, together with the specific aspects of a very high luminosity
tau-charm factory. Subjects connected to Kaon decay physics are not discussed
here, being part of another INFN Roadmap working group. The significance of the
project and the impact on INFN are also discussed. All the documentation
related to the activities of the working group can be found in
http://www.roma1.infn.it/people/bini/roadmap.html.Comment: INFN Roadmap Report: 86 pages, 25 figures, 9 table
Arbeitslosigkeit und Stellenannahmebereitschaft: Erste Ergebnisse eines Faktoriellen Survey Moduls
A quark model calculation of γγ→ππ including final-state interactions
A quark model calculation of the processes γγ→π+π- and γγ→π0π0 is performed. At tree level, only charged pions couple to the initial state photons and neutral pions are not expected in the final state. However, a small but significant γγ→π0π0 cross section is observed. We demonstrate that this may be accounted for by a rotation in isospin space induced by final-state interactions. The resulting π+π- cross section is in good agreement with experiment, while the π0π0 cross section is in qualitative agreement with the data