Search results for "RESONANCES"
showing 10 items of 67 documents
Search for new particles in two-jet final states in 7 TeV proton-proton collisions with the ATLAS detector at the LHC
2010
19 páginas, 2 figuras, 1 tabla.-- et al.(ATLAS Collaboration).
Resonances for nonanalytic potentials
2009
We consider semiclassical Schr"odinger operators on $R^n$, with $C^infty$ potentials decaying polynomially at infinity. The usual theories of resonances do not apply in such a non-analytic framework. Here, under some additional conditions, we show that resonances are invariantly defined up to any power of their imaginary part. The theory is based on resolvent estimates for families of approximating distorted operators with potentials that are holomorphic in narrow complex sectors around $R^n$.
Charmed baryon resonances with heavy-quark symmetry
2009
We study charmed baryon resonances that are generated dynamically from a coupled-channel unitary approach that implements heavy-quark symmetry. Some states can already be identified with experimental observations, such as $\Lambda_c(2595)$,$\Lambda_c(2660)$, $\Sigma_c(2902)$ or $\Lambda_c(2941)$, while others need a compilation of more experimental data as well as an extension of the model to include higher order contributions. We also compare our model to previous SU(4) schemes.
Weak decays of heavy hadrons into dynamically generated resonances
2016
In this paper, we present a review of recent works on weak decay of heavy mesons and baryons with two mesons, or a meson and a baryon, interacting strongly in the final state. The aim is to learn about the interaction of hadrons and how some particular resonances are produced in the reactions. It is shown that these reactions have peculiar features and act as filters for some quantum numbers which allow to identify easily some resonances and learn about their nature. The combination of basic elements of the weak interaction with the framework of the chiral unitary approach allow for an interpretation of results of many reactions and add a novel information to different aspects of the hadron…
Exotic dynamically generated baryons with negative charm quantum number
2010
Following a model based on the SU(8) symmetry that treats heavy pseudoscalars and heavy vector mesons on an equal footing, as required by heavy quark symmetry, we study the interaction of baryons and mesons in coupled channels within an unitary approach that generates dynamically poles in the scattering T-matrix. We concentrate in the exotic channels with negative charm quantum number for which there is the experimental claim of one state.
Hidden beauty molecules within the local hidden gauge approach and heavy quark spin symmetry
2013
Using a coupled channel unitary approach, combining the heavy quark spin symmetry and the dynamics of the local hidden gauge, we investigate the meson-meson interaction with hidden beauty and obtain several new states. Both I = 0 and I = 1 states are analyzed, and it is shown that in the I = 1 sector, the interactions are too weak to create any bound states within our framework. In total, we predict with confidence the existence of six bound states and six more possible weakly bound states. The existence of these weakly bound states depends on the influence of the coupled channel effects.
The role of f(0)(1710) in the phi omega threshold peak of J/Psi -> gamma phi omega
2013
We study the process J/Psi -> gamma phi omega, measured by the BES experiment, where a neat peak close to the phi omega threshold is observed and is associated to a scalar meson resonance around 1800 MeV. We make the observation that a scalar resonance coupling to phi omega unavoidably couples strongly to K (K) over bar, but no trace of a peak is seen in the K (K) over bar spectrum of the J/Psi -> gamma K (K) over bar at this energy. This serves us to rule out the interpretation of the observed peak as a signal of a new resonance. After this is done, a thorough study is performed on the production of a pair of vector mesons and how its interaction leads necessarily to a peak in the J/Psi ->…
Graphical Schemes Designed to Display and Study the Long-term Variations of Schumann Resonance
2019
This work proposes and illustrates a graphical approach aimed at studying a wide range of features of the ELF horizontal magnetic field signal recorded at the Sierra Nevada station (Spain). In addition to the traditional long-term variations in the parameters of the first three Schumann resonances (their amplitudes, central frequencies and widths), many other properties such as the saturations of the magnetometers, anomalous values for the parameters or spectra with any kind of particularities are taken into consideration in this work. These features can provide us with complementary information about the long-term variation of Schumann resonances, give an estimation of the extent up to whi…
Solar storm effects during Saint Patrick's Days in 2013 and 2015 on the Schumann resonances measured by the ELF station at Sierra Nevada (Spain)
2016
First measurement of the charge asymmetry in boosted top quark pair production in the ATLAS experiment using the Grid-based Tier-3 facility at IFIC-V…
2016
The Large Hadron Collider (LHC) at CERN is the largest collider ever built. It is assembled in the same 27 km tunnel where Large Electron-Positron Collider (LEP) used to be, $\sim$ 100 m underground, near Geneva (Switzerland). The main interaction points have four experiments installed: ATLAS, CMS, ALICE and LHCb. The LHC is designed to collide two proton beams, that circulate in opposite directions, each with an energy of up to 7 TeV, reaching a centre-of-mass energy up to 14 TeV. %%%%%%%%% The ATLAS experiment is a general-purpose detector designed to exploit the potential of the LHC. With a total weight of 7000 tonnes, ATLAS is the heaviest experiment at the LHC. It has 42 m of total len…