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.
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.
8994892
Anomalous action in gauge invariant, nonlocal, dynamical quark model
Anomalous sector of chiral Lagrangian is calculated in a gauge invariant, nonlocal, dynamical quark model. The Wess-Zumino term is proved coming from two kinds of sources, one is independent of and another dependent on dynamical quark self energy Sigma(k(2)). p(6) and more higher order anomalous sectors come only from Sigma(k(2)) dependent source. After some cancellation, standard Wess-Zumino action is obtained. (C) 2003 Published by Elsevier Science B.V.
846321
ANOMALY AND ANOMALY-FREE TREATMENT OF QFT's BASED ON SYMMETRY-PRESERVING LOOP REGULARIZATION
The triangle anomaly in massless and massive QED is investigated by adopting the symmetry-preserving loop regularization method proposed recently in Refs. 1 and 2. The method is realized in the initial dimension of theory without modifying the original Lagrangian, it preserves symmetries under non-Abelian gauge and Poincare transformations in spite of the existence of two intrinsic mass scales Mc and μs which actually play the roles of UV- and IR-cutoff respectively. The axial-vector–vector-vector (AVV) triangle diagrams in massless and massive QED are evaluated explicitly by using the loop regularization. It is shown that when the momentum k of external state is soft with , m2 (m is the mass of loop fermions) and Mc → ∞, both massless and massive QED become anomaly free. The triangle anomaly is found to appear as quantum corrections in the case that m2, and Mc → ∞. Especially, it is justified that in the massless QED with μs = 0 and Mc → ∞, the triangle anomaly naturally exists as quantum effects in the axial-vector current when the ambiguity caused by the trace of gamma matrices with γ5 is eliminated by simply using the definition of γ5. It is explicitly demonstrated how the Ward identity anomaly of currents depends on the treatment for the trace of gamma matrices, which enables us to make a clarification whether the ambiguity of triangle anomaly is caused by the regularization scheme in the perturbation calculations or by the trace of gamma matrices with γ5. For comparison, an explicit calculation based on the Pauli–Villars regularization and dimensional regularization is carried out and the possible ambiguities of Ward identity anomalies caused from these two regularization schemes are carefully discussed, which include the ambiguities induced by the treatment of the trace of gamma matrices with γ5 and the action of the external momentum on the amplitude before the direct calculation of the AVV diagram.
119236022
Estimates for X ( 4350 ) decays from the effective Lagrangian approach
The strong and electromagnetic decays of X(4350) with quantum numbers J{sup P}=0{sup ++} and 2{sup ++} have been studied by using the effective Lagrangian approach. The coupling constant between X(4350) and D{sub s}*D{sub s0}* is determined with the help of the compositeness condition which means that X(4350) is a bound state of D{sub s}*D{sub s0}*. Other coupling constants applied in the calculation are determined phenomenologically. Our numerical results show that, using the present data, the possibility that X(4350) is a D{sub s}*D{sub s0}* molecule cannot be ruled out within the present model.
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.
119606190
Quantization of the static space-time
A four-dimensional Lorentzian static space-time is equivalent to three-dimensional Euclidean gravity coupled to a massless Klein-Gordon field. By canonically quantizing the coupling model in the framework of loop quantum gravity, we obtain a quantum theory that actually describes quantized static space-times. The kinematical Hilbert space is the product of the Hilbert space of gravity with that of imaginary scalar fields. It turns out that the Hamiltonian constraint of the 2+1 model corresponds to a densely defined operator in the underlying Hilbert space, and hence it is finite without renormalization. As a new point of view, this quantized model might shed some light on a few physical problems concerning quantum gravity.
120406708
Analysis methods for results in gamma-ray astronomy
117504817
The X-ray spectra and XUV excess of some AGNs.
118365916
Geminga Pulsar in Cos-B and Heao-B Observations