Search results for "radiative decay"
showing 10 items of 55 documents
Search for the decay K-s -> pi(0)e(+)e(-)
2001
Abstract A search for the decay K S →π 0 e + e − has been made using the NA48 detector at the CERN SPS. Using data collected in 1999 during a 40-hour run with a high-intensity KS beam, an upper limit for the branching fraction B (K S →π 0 e + e − ) −7 at 90% confidence level has been obtained.
Radiative decays of theY(3940),Z(3930), and theX(4160)as dynamically generated resonances
2011
We study the radiative decay properties of the charmoniumlike $X$, $Y$, and $Z$ mesons generated dynamically from vector-meson--vector-meson interaction in the framework of a unitarized hidden-gauge formalism. In the present work, we calculate the one- and two-photon decay widths of the hidden-charm $Y(3940)$, $Z(3930)$ [or $X(3915)$], and $X(4160)$ mesons in the framework of the vector-meson dominance formalism. We obtain good agreement with the experiment in case of the two-photon width of the $X(3915)$, which we associate to the ${2}^{+}$ resonance that we find at 3922 MeV. However, in view of discrepancies with a different approach that also considers the resonances as molecular states,…
Three methods to detect the predicted DDˉ scalar meson X(3700)
2012
In analogy to the f_0(500), which appears as a $\pi \pi $ resonance in chiral unitary theory, and the f_0(980), which appears as a quasibound $K \bar K$ state, the extension of this approach to the charm sector also predicts a quasibound $D \bar D $ state with mass around 3720 MeV, named as X(3700), for which some experimental support is seen in the $e^+ e^- \to J/\psi D \bar D $ reaction close to the $D \bar D $ threshold. In the present work we propose three different experiments to observe it as a clear peak. The first one is the radiative decay of the $\psi(3770)$, $\psi(3770) \to \gamma X(3700) \to \gamma \eta \eta '$. The second one proposes the analogous reaction $\psi(4040) \to \gam…
V P gamma radiative decay of resonances dynamically generated from the vector meson-vector meson interaction
2010
We evaluate the radiative decay into a vector, a pseudoscalar and a photon of several resonances dynamically generated from the vector-vector interaction. The process proceeds via the decay of one of the vector components into a pseudoscalar and a photon, which have an invariant mass distribution very different from phase space as a consequence of the two vector structure of the resonances. Experimental work along these lines should provide useful information on the nature of these resonances.
Radiative decay of rho(0) and phi mesons in a chiral unitary approach
1999
We study the rho^0 and phi decays into pi^+ pi^- gamma, pi^0 pi^0 gamma and phi into pi^0 eta gamma using a chiral unitary approach to deal with the final state interaction of the M M system. The final state interaction modifies only moderately the large momenta tail of the photon spectrum of the rho^0 --> pi^+ pi^- gamma decay. In the case of phi decay the contribution to pi^+ pi^- gamma and pi^0 pi^0 gamma decay proceeds via kaonic loops and gives a distribution of pi pi invariant masses in which the f_0(980) resonance shows up with a very distinct peak. The spectrum found for phi --> pi^0 pi^0 gamma decay agrees with the recent experimental results obtained at Novosibirsk. The bran…
Dynamically generated resonances from the vector octet-baryon decuplet interaction and their radiative decays into γ-baryon decuplet
2009
The dynamically generated resonances from vector meson-baryon decuplet are studied using Lagrangians of the hidden gauge theory for vector interactions. One shows that some of the generated states can be associated with some known baryon resonances in the PDG data, while others are predictions for new states. Furthermore, we calculate the radiative decay widths of these resonances into a photon and a baryon decuplet.
Radiative decay of the dynamically generated open and hidden charm scalar meson resonancesDs0*(2317)andX(3700)
2007
We present the formalism for the decay of dynamically generated scalar mesons with open- or hidden charm and give results for the decay of ${D}_{s0}^{*}(2317)$ to $\ensuremath{\gamma}{D}_{s}^{*}$ plus that of a hidden charm scalar meson state predicted by the theory around 3700 MeV decaying into $\ensuremath{\gamma}J/\ensuremath{\psi}$.
The radiative decay of $\psi(3770)$ into the predicted scalar state X(3700)
2009
5 pages, 1 figure.-- ISI article identifier:000267299600009.-- ArXiv pre-print avaible at:http://arxiv.org/abs/0805.0499
Study of thef2(1270),f2′(1525),K¯2*(1430),f0(1370)andf0(1710)production fromψ(nS)andϒ(nS)decays
2015
Based on previous studies that support the important role of the ${f}_{2}(1270)$, ${f}_{2}^{\ensuremath{'}}(1525)$, and ${\overline{K}}_{2}^{*}(1430)$ resonances in the $J/\ensuremath{\psi}[\ensuremath{\psi}(2S)]\ensuremath{\rightarrow}\ensuremath{\phi}(\ensuremath{\omega})VV$ decays, we make an analysis of the analogous decays of $\mathrm{\ensuremath{\Upsilon}}(1S)$ and $\mathrm{\ensuremath{\Upsilon}}(2S)$, taking into account recent experimental data. In addition, we study the $J/\ensuremath{\psi}$ and $\ensuremath{\psi}(2S)$ radiative decays and we also made predictions for the radiative decay of $\mathrm{\ensuremath{\Upsilon}}(1S)$ and $\mathrm{\ensuremath{\Upsilon}}(2S)$ into $\ensurem…
Observation ofη′→ωe+e−
2015
Based on a sample of eta' mesons produced in the radiative decay J/psi -> gamma eta' in 1.31 x 10(9) J/psi events collected with the BESIII detector, the decay eta' -> omega e(+)e(-) is observed for the first time, with a statistical significance of 8 sigma. The branching fraction is measured to be B(eta' -> omega e(+)e(-)) = (1.97 +/- 0.34(stat) +/- 0.17(syst)) x 10(-4), which is in agreement with theoretical predictions. The branching fraction of eta' -> omega gamma is also measured to be (2.55 +/- 0.03(stat) +/- 0.16(syst)) x 10(-2), which is the most precise measurement to date, and the relative branching fraction B(eta' -> omega e(+)e(-))/B(eta' -> omega gamma) is determined to be (7.7…