17,548 research outputs found
The Y(3940), Z(3930) and the X(4160) as dynamically generated resonances from the vector-vector interaction
We study the vector-vector interaction within the framework of the hidden
gauge formalism for the sector with quantum numbers charm C=0 and strangeness
S=0 in the region around 4000 MeV. We get five poles, three of which could be
identified with the Y(3940), Z(3930) and X(4160). These poles appear with
quantum numbers I=0 and and , respectively, and
can be considered as hadronic molecules made of ,
.Comment: to appear in Proceedings of XIII International Conference on Hadron
Spectroscopy, November 29 - December 4, 2009, Florida State Universit
Screening in three-dimensional QED with arbitrary fermion mass
We compute the quark--antiquark potential in three dimensional massive
Quantum Electrodynamics for arbitrary fermion mass. The result indicates that
screening prevails for any quark masses, contrary to the classical
expectations, generalizing our previous result obtained for large masses. We
also test the validity of several approximation schemes using a detailed
numerical analysis. The classical result is still reproduced for small
separation of the quarks.Comment: latex, 10 pages, 4 figures (6 ps-files
Detailed atmospheric abundance analysis of the optical counterpart of the IR source IRAS 16559-2957
We have undertaken a detailed abundance analysis of the optical counterpart
of the IR source IRAS16559-2957 with the aim of confirming its possible
post-AGB nature. The star shows solar metallicity and our investigation of a
large number of elements including CNO and 12C/13C suggests that this object
has experienced the first dredge-up and it is likely still at RGB stage.Comment: 10 pages, 4 figures, 4 tables. To be published by Revista Mexicana de
Astronomia y Astrofisica, April 201
A venting alarm system for cryogenic liquids
Alarm system for cryogenic fluid storage tank
Charm at FAIR
Charmed mesons in hot and dense matter are studied within a self-consistent
coupled-channel approach for the experimental conditions of density and
temperature expected at the CBM experiment at FAIR/GSI. The meson spectral
function broadens with increasing density with an extended tail towards lower
energies due to and
excitations. The in-medium meson mass increases with density. We also
discuss the consequences for the renormalized properties in nuclear matter of
the charm scalar and D(2400), and the predicted hidden charm
X(3700) resonances at FAIR energies.Comment: 6 pages, 3 figures, to appear in the proceedings of ExcitedQCD 09,
Zakopane, Poland, 8-14 February 200
Prediction of narrow and resonances with hidden charm above 4 GeV
The interaction between various charmed mesons and charmed baryons are
studied within the framework of the coupled channel unitary approach with the
local hidden gauge formalism. Several meson-baryon dynamically generated narrow
and resonances with hidden charm are predicted with mass
above 4 GeV and width smaller than 100 MeV. The predicted new resonances
definitely cannot be accommodated by quark models with three constituent quarks
and can be looked for at the forthcoming PANDA/FAIR experiments.Comment: 4 pages, 3 figure
meson in dense matter
We study the properties of mesons in nuclear matter using a
unitary approach in coupled channels within the framework of the local hidden
gauge formalism and incorporating the decay channel in matter. The
in-medium interaction accounts for Pauli blocking effects and
incorporates the self-energy in a self-consistent manner. We also
obtain the (off-shell) spectral function and analyze its behaviour
at finite density and momentum. At normal nuclear matter density, the meson feels a moderately attractive potential while the width
becomes five times larger than in free space. We estimate the transparency
ratio of the reaction, which we propose as
a feasible scenario at present facilities to detect the changes of the
properties of the meson in the nuclear medium.Comment: 26 pages, 9 figures, one new section added, version published in
Phys. ReV. C, http://link.aps.org/doi/10.1103/PhysRevC.82.04521
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