29,669 research outputs found
is likely to be a glueball
On the basis of the recent results of and , measured by the BES Collaboration
in radiative decays, combined with the PS185 experiment of , we argue that because of its very
narrow partial decay widths to and ( less than ),
its large production rate in radiative decays, and its flavor-
symmetric couplings to and , the is very likely
to be a glueball.Comment: 6 pages in Latex, talk presented at the CCAST Workshop on Tau-Charm
Factory, Beijing, November 199
Search for charmonium and bottomonium states in at B factories
We study the production of charmonium states in at B factories with (n=1,2,3), (m=1,2), and
. In the S and P wave case, contributions of tree-QED with one-loop
QCD corrections are calculated within the framework of nonrelativistic
QCD(NRQCD) and in the D-wave case only the tree-QED contribution are
considered. We find that in most cases the QCD corrections are negative and
moderate, in contrast to the case of double charmonium production , where QCD corrections are positive and large in most cases. We
also find that the production cross sections of some of these states in
are larger than that in by an
order of magnitude even after the negative QCD corrections are included. So we
argue that search for the X(3872), X(3940), Y(3940), and X(4160) in at B factories may be helpful to clarify the nature of these
states. For completeness, the production of bottomonium states in
annihilation is also discussed.Comment: 13pages, 4 figure
The Color-Octet intrinsic charm in and decays
Color-octet mechanism for the decay B\to \eta^\prime X is proposed to explain
the large branching ratio of Br(B\to \eta^\prime X)\sim 1\times 10^{-3}
recently announced by CLEO. We argue that the inclusive \eta^\prime production
in B decays may dominantly come from the Cabbibo favored b\to (\bar c c)_8s
process where \bar c c pair is in a color-octet configuration, and followed by
the nonperturbative transition (\bar c c)_8\to \eta^\prime X. The color-octet
intrinsic charm component in the higher Fock states of \eta^\prime is crucial
and is induced by the strong coupling of \eta^\prime to gluons via QCD axial
anomaly.Comment: 9 pages, RevTex, 1 PS figur
Transmitted sound field due to an impulsive line acoustic source bounded by a plate followed by a vortex sheet
The propagation of sound due to a line acoustic source in the moving stream across a semiinfinite vortex sheet which trails from a rigid plate is examined in a linear theory for the subsonic case. A solution for the transmitted sound field is obtained with the aid of multiple integral transforms and the Wiener-Hopf technique for both the steady state (time harmonic) and initial value (impulsive source) situations. The contour of inverse transform and hence the decomposition of the functions are determined through causality and radiation conditions. The solution obtained satisfies causality and the full Kutta conditions. The transmitted sound field is composed of two waves in both the stady state and initial value problems. One is the wave scattered from the edge of the plate which is associated with the bow wave and the instability wave. These waves exist in the downstream sectors. The other is the wave transmitted through the vortex sheet which is also associated with the instability wave. Regional divisions of the transmitted sound field are identified
Reply to Comment on "Chiral suppression of scalar glueball decay"
Reply to the comment of Chao, He, and Ma
Multiquark Hadrons
A number of candidate multiquark hadrons, i.e., particle resonances with
substructures that are more complex than the quark-antiquark mesons and
three-quark baryons that are prescribed in the textbooks, have recently been
observed. In this talk I present: some recent preliminary BESIII results on the
near-threshold behavior of sigma(e+e- --> Lambda Lambda-bar) that may or may
not be related to multiquark mesons in the light- and strange-quark sectors;
results from Belle and LHCb on the electrically charged, charmoniumlike
Z(4430)^+ --> pi^+ psi ' resonance that necessarily has a four-quark
substructure; and the recent LHCb discovery of the P_c(4380) and P_c(4450)
hidden-charm resonances seen as a complex structure in the J/psi p invariant
mass distribution for Lambda_b --> K^-J/psi p decays and necessarily have a
five-quark substructure and are, therefore, prominent candidates for pentaquark
baryons.Comment: 12 pages, 9 figures, summary of a talk presented at the 12th
Conference on Hypernuclear and Strange Particle Physics (HYP2015), September
7-12, 2015 Sendai, JAPAN. To appear in the JPS Conference proceeding
New high fill-factor triangular micro-lens array fabrication method using UV proximity printing
A simple and effective method to fabricate a high fill-factor triangular
microlens array using the proximity printing in lithography process is
reported. The technology utilizes the UV proximity printing by controlling a
printing gap between the mask and substrate. The designed approximate triangle
microlens array pattern can be fabricated the high fill-factor triangular
microlens array in photoresist. It is due to the UV light diffraction to
deflect away from the aperture edges and produce a certain exposure in
photoresist material outside the aperture edges. This method can precisely
control the geometric profile of high fill factor triangular microlens array.
The experimental results showed that the triangular micro-lens array in
photoresist could be formed automatically when the printing gap ranged from 240
micrometers to 840 micrometers. The gapless triangular microlens array will be
used to increases of luminance for backlight module of liquid crystal displays.Comment: Submitted on behalf of EDA Publishing Association
(http://irevues.inist.fr/handle/2042/16838
Epigenetic silencing of SOCS3 expression contributes to fibrosis in Crohn’s disease
Identified risk polymorphisms affecting the Jak-STAT3 pathway in patients with Crohn’s disease could affect TGF-β1 and collagen I expression and in the pathway’s negative regulator, SOCS3. Genetic factors, however, account for only ~25% of disease. Epigenetic events also shape gene expression. Recent experiments showed that autocrine IL-6 production in mesenchymal cells, subepithelial myofibroblasts (SEMF) and muscle cells, of patients with fibrostenotic Crohn’s disease causes sustained Jak-STAT3 activity, excess TGF-β1 and Collagen I production and fibrosis. SOCS3 paradoxically decreased in these cells. We now identify epigenetic mechanisms that silence SOCS3 expression in SEMF of patients with fibrostenotic Crohn’s disease. In a previous experiment, using isolated SEMF of normal ileum and affected ileum from patients with each Crohn’s phenotype, inflammatory (Montreal B1), fibrostenotic (B2) and penetrating (B3), we confirmed decreased SOCS3 protein levels were unique to B2 patients. Expression of miR-19b increased in SEMF of affected ileum. SOCS3 transcriptional activity decreased after transfection of miR-19b mimic and increased when antagomiR-19b was expressed. Epigenetic silencing of SOCS3 in ileal SEMF of patients with fibrostenotic Crohn’s disease occurs by increased miR-19b mediated inhibition of SOCS3
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Applying New Models of Care to Meet Patient Needs in Integrative Oncology.
Cancellation of Infrared Divergences in Hadronic Annihilation Decays of Heavy Quarkonia
In the framework of a newly developed factorization formalism which is based
on NRQCD, explicit cancellations are shown for the infrared divergences that
appeared in the previously calculated hadronic annihilation decay rates of
P-wave and D-wave heavy quarkonia. We extend them to a more general case that
to leading order in and next-to-leading order in , the infrared
divergences in the annihilation amplitudes of color-singlet
pair can be removed by including the contributions of
color-octet operators ,
, ... in NRQCD. We also give the decay widths of
at leading order in .Comment: 8 pages, LaTex(3 figures included), to be publishe
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