12058058
Detectability of Upgoing Sleptons
Some supersymmetric models predicted long lived charged sleptons. Following Albuquerque, Burdman and Chacko \cite{albu}, we consider an exact process where the $ \widetilde{\tau}$, the supersymmetry partner of $\tau$ lepton, are produced inside the earth by collisions of high energy neutrinos with nucleons. We detailedly investigate the possible signals of upgoing $ \widetilde{\tau}$ by comparing with the background muons where atmospheric neutrino flux is taken into account. The realistic spectra shows that km-scale experiments could see as many as 69 events a year by using the Waxman-Bahcall limit on the extraterrestrial neutrino flux.
120406708
Analysis methods for results in gamma-ray astronomy
123957691
Study on a Cellmap for the Reconstruction of Cosmic Ray Tracks in Drift Chamber
Taking L3 Cosmics experiment (L3 + C) as an example, we discussed a new Cellmap to reconstruct the hit in drift chamber of magnetic spectrometer for the very inclined comic-ray tracks, and compared the reconstruction results with the standard Cellmap of L3 + C. It shows that, for the very inclined cosmic-ray tracks, the new Cellmap can reconstruct more hits than the standard Cellmap, and the distribution of chi(2) of track reconstruction is also improved.
122947463
COSMIC RAY MUON MEASUREMENT BY L3 SPECTROMETER AT CERN
L3 + C is a branch experiment on L3 magnet spectrometer, which is located on the ring of LEP accelerator at CERN. To take the advantage of L3 muon chambers in its low threshold, wide dynamic range and high resolution, the momentum of cosmic ray muons in the range of 15–2000 GeV/c at a shallow depth of 30 m of molasse can be measured precisely. Since 1998, a scintillator detector system, a new fast trigger and DAQ system, and a small air shower array had been established for study the CR muon events independently. Up to August 2000, 8 billion muons and 25 million air shower events had been recorded. The first results for CR muon spectrum and the charge ratio etc. had been obtained.
125881447
The neutrino mass and the periodicity of the neutrino burst from SN1987A
117951678
Searching for Point Source Signals through Muons
118351603
Strong and radiative decays of X(3872) as a hadronic molecule with a negative parity
Properties of X(3872) are studied by regarding it as a $DD^{\ast}$ hadronic molecule with $J^{PC} = 2^{-+}$ in the phenomenological Lagrangian approach. We find that our model with about 97.6% isospin zero component explains the existing data nicely, for example, the ratio $\mathcal{B}(X(3872) \to J/\psi\pi^+\pi^-\pi^0)/\mathcal{B}(X(3872) \to J/\psi\pi^+\pi^-)$. We predict the partial widths of the radiative decays of $X(3872) \to \gamma J/\psi$, $\gamma \psi(2S) $ and the strong decays of $X(3872) \to J/\psi \pi^+ \pi^-$, $J/\psi \pi^+\pi^-\pi^0$ as well as $X(3872) \to \chi_{cJ}\pi^0$. Our analysis shows that the measurement of the ratio $\mathcal{B}(X(3872) \to \chi_{c0}\pi^0)/\mathcal{B}(X(3872) \to \chi_{c1}\pi^0)$ may signal the nature of X(3872).
121889894
ORBITALLY EXCITED STATES OF QUARKONIA IN A NONRELATIVISTIC MODEL
Having succeeded in predicting the S wave spectra and decays of and mesons, Bhaghyesh, K. B. Vijaya Kumar and A. P. Monteiro, J. Phys. G: Nucl. Part. Phys.38, 085001 (2011), in this article, we apply our nonrelativistic quark model to calculate the spectra and decays of the orbitally excited states (P- and D-waves) of heavy quarkonia. The full potential used in our model consists of a Hulthen potential and a confining linear potential. The spin hyperfine, spin-orbit and tensor interactions are introduced to obtain the masses of the P- and D-wave states. The three-dimensional harmonic oscillator wave function is employed as a trial wave function to obtain the mass spectra. The model parameters and the wave function that reproduce the mass spectra of and mesons are used to investigate their decay properties. The two-photon decay widths, two-gluon decay widths and E1 radiative decay widths are calculated. The obtained values are compared with the experimental results and those obtained from other theoretical models.
118615785
Dense baryonic matter in conformally-compensated hidden local symmetry: Vector manifestation and chiral symmetry restoration
We find that, when the dilaton is implemented as a (pseudo-)Nambu-Goldstone boson using a conformal compensator or "conformon" in a hidden gauge symmetric Lagrangian written to $O(p^4)$ from which baryons arise as solitons, namely, skyrmions, the vector manifestation and chiral symmetry restoration at high density predicted in hidden local symmetry theory --- which is consistent with Brown-Rho scaling --- are lost or sent to infinite density. It is shown that they can be restored if in medium the behavior of the $\omega$ field is taken to deviate from that of the $\rho$ meson in such a way that the flavor $U(2)$ symmetry is strongly broken at increasing density. The hitherto unexposed crucial role of the $\omega$ meson in the structure of elementary baryon and multibaryon systems is uncovered in this work. In the state of half-skyrmions to which the skyrmions transform at a density $n_{1/2}^{} \gtrsim n_0^{}$ (where $n_0^{}$ is the normal nuclear matter density), characterized by the vanishing (space averaged) quark condensate but nonzero pion decay constant, the nucleon mass remains more or less constant at a value $\gtrsim$ 60 \% of the vacuum value indicating a large component of the nucleon mass that is not associated with the spontaneous breaking of chiral symmetry. We discuss its connection to the chiral-invariant mass $m_0^{}$ that figures in the parity-doublet baryon model.
118886519
Skyrmions with vector mesons in the hidden local symmetry approach
(hWZ) terms. We write a general “master formula” that allows us to determine the parameters of the HLS Lagrangian from a class of holographic QCD models valid at large Nc and � (’t Hooft constant) limit by integrating out the infinite towers of vector and axial-vector mesons other than the lowest � and ! mesons. Within this approach we find that the physical properties of the Skyrmion as the solitonic description of baryons are independent of the HLS parameter a. Therefore the only parameters of the model are the pion decay constant and the vector meson mass. Once determined in the meson sector, we have a totally parameter-free theory that allows us to study unequivocally the role of light vector mesons in the Skyrmion structure. We find, as suggested by Sutcliffe, that
51032910
Strong and radiative decays of the D(s0)*(2317) meson in the DK-molecule picture
We consider a possible interpretation of the new charm-strange meson D* s0 (2317) as a hadronic molecule-a bound state of D and K mesons. Using an effective Lagrangian approach, we calculate the strong D* s0 → D s π 0 and radiative D* s0 → D* s γ decays. A new impact related to the DK molecular structure of the D* s0 (2317) meson is that the presence of u(d) quarks in the D and K mesons gives rise to a direct strong isospin-violating transition D* s0 → D s π 0 in addition to the decay mechanism induced by η - π 0 mixing considered previously. We show that the direct transition dominates over the 17 - π 0 mixing transition in the D* s0 → D s π 0 decay. Our results for the partial decay widths are consistent with previous calculations.