122387115
Coordinates Used in Derivation of Hawking Radiation via Hamilton-Jacobi Method
Coordinates used in derivation of Hawking radiation via Hamilton-Jacobi method are investigated more deeply. In the case of a 4-dimensional Schwarzschild black hole, a direct computation leads to a wrong result. In the meantime, making use of the isotropic coordinate or invariant radial distance, we can get the correct conclusion. More coordinates including Painleve and Eddington-Finkelstein are tried to calculate the semi-classical Hawking emission rate. The reason of the discrepancy between naive coordinate and well-behaved coordinates is also discussed.
120955883
Dirac Particles' Hawking Radiation from a Schwarzschild Black Hole
Considering energy conservation and the backreaction of particles to spacetime, we investigate the massless/massive Dirac particles' Hawking radiation from a Schwarzschild black hole. The exact expression of the emission rate near the horizon is obtained and the result indicates that Hawking radiation spectrum is not purely thermal. The result obtained is consistent with the results obtained before. It satisfies the underlying unitary theory and offers a possible mechanism to explain the information loss paradox. Whereas the improved Damour–Ruffini method is more concise and understandable.
122027792
Casimir Effect of Massive Scalar Field with Hybrid Boundary Condition in （1＋1）-Dimensional Spacetime
The Casimir energy of massive scalar field with hybrid (Dirichlet–Neumann) boundary condition is calculated. In order to regularize the model, the typical methods named as mode summation method and Green's function method are used respectively. It is found that the regularized zero-point energy density depends on the scalar field's mass. When the field is massless, the result is consistent with previous literatures.
59226668
Observation of X (3872) in B →x (3872)Kπ decays
We report the first observation of B-0 -> X(3872)(K+pi(-)) and evidence for B+ -> X(3872)(K-0 pi(+)). We measure the product of branching fractions for the former to be B(B-0 -> X(3872)(K+pi(-)) x B(X(3872) -> J/psi pi(+)pi(-)) = (7.9 +/- 1.3(stat) +/- 0.4(syst) x 10(-6) and find that B-0 -> X(3872)K*(892)(0) does not dominate the B-0 -> X(3872)K+pi(-) decay mode. We also measure B(B+ -> X(3872)(K-0 pi(+))) x B(X(3872) -> J/psi pi(+)pi(-)) = (10.6 +/- 3.0(stat) +/- 0.9(syst) x 10(-6). This study is based on the full data sample of 711 fb(-1) (772 x 10(6)B (B) over bar pairs) collected at the Upsilon(4S) resonance with the Belle detector at the KEKB collider.