Carbon Dioxide Enhanced Oil Recovery

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Non-unitarity and non-reciprocity in scattering from real potentials in presence of confined non-linearity

Investigations of scattering in presence of non-linearity which have just begun require the confinement of both the potential, $V(x)$, and the non-linearity, $\gamma f(|\psi|)$. There could be two options for the confinement. One is the finite support on $x \in [-L,L]$ and the other one is on $x \in [0,L]$. Here, we consider real Hermitian potentials and report a surprising disparate behaviour of these two types of confinements. We prove that in the first option the symmetric potential enjoys reciprocity of both reflectivity ($R$) and transmitivity ($T$) and their unitarity. More interestingly, the asymmetry in $V(x)$ causes non-unitarity ($R+T\ne 1$) and the non-reciprocity (reciprocity) of $T (R)$. On the other hand, the second option of confinement gives rise to an essential non-unitarity even when $V(x)$ is symmetric about a point in $[0,L]$. In the absence of symmetry there occurs non-reciprocity of both $R$ and $T$.Comment: 8 pages, Five Figures each with three parts a.b.

Gaussian-random Ensembles of Pseudo-Hermitian Matrices

Attention has been brought to the possibility that statistical fluctuation properties of several complex spectra, or, well-known number sequences may display strong signatures that the Hamiltonian yielding them as eigenvalues is PT-symmetric (Pseudo-Hermitian). We find that the random matrix theory of pseudo-Hermitian Hamiltonians gives rise to new universalities of level-spacing distributions other than those of GOE, GUE and GSE of Wigner and Dyson. We call the new proposals as Gaussian Pseudo-Orthogonal Ensemble and Gaussian Pseudo-Unitary Ensemble. We are also led to speculate that the enigmatic Riemann-zeros (${1 \over 2}\pm i t_n)$ would rather correspond to some PT-symmetric (pseudo-Hermitian) Hamiltonian.Comment: Invited Talk Delivered in II International Workshop on `Pseudo-Hermitian Hanmiltonians in Physics' at Prague, June 14-16, 200

Light output simulation of LYSO single crystal

We used the Geant4 simulation toolkit to estimate the light collection in a LYSO crystal by using cosmic muons and E=105 MeV electrons. The light output as a function of the crystal length is studied. Significant influence of the crystal wrapping in the reflective paper and optical grease coupling to the photodetectors on the light output is demonstrated.Comment: 9 pages, 5 figure