Quantum enhanced imaging of nonuniform refractive profiles

In this work, quantum metrology techniques are applied to the imaging of objects with a nonuniform refractive spatial profile. A sensible improvement on the classical accuracy is shown to be found when the "Twin Beam (TWB) State" is used. In particular, exploiting the multimode spatial correlation, naturally produced in the Parametric Down Conversion (PDC) process, allows a 2D reconstruction of complex spatial profiles, thus enabling an enhanced imaging. The idea is to use one of the spatially multimode beams to probe the sample and the other as a reference to reduce the noise. A similar model can also be used to describe wave front distortion measurements. The model is meant to be followed by a first experimental demonstration of such enhanced measurement scheme

The effects of the small t properties of hadronic scattering amplitude on the determination its real part

Taking into account the different forms of the Coulomb-hadron interference phase and the possible spin-flip contribution the new analysis of the experimental data of the proton-antiproton elastic scattering at $3.8 < p_L <6.0 \$GeV/c and small momentum transfer is carried out. It is shown that the size of the spin-flip amplitude can be determined from the form of the differential cross sections at small $t$, and the deviation of $\rho(s,t)$ obtained from the examined experimental data of the $p\bar{p}$ scattering from the analysis \cite{Kroll}, based on the dispersion relations, is conserved in all xamined assumptions. The analysis of the proton-proton elastic scattering at $9 < p_L < 70 \$GeV/c also shows the impact of the examined effects on the form of the differential cross sections.Comment: 13 pages, 3 figure

Systematic study of the PDC speckle structure for quantum imaging applications

Sub shot noise imaging of weak object by exploiting Parametric Down Converted light represents a very interesting technological development. A precise characterization of PDC speckle structure in dependence of pump beam parameters is a fundamental tool for this application. In this paper we present a first set of data addressed to this purpose

Recent experiments performed at "Carlo Novero" lab at INRIM on Quantum Information and Foundations of Quantum Mechanics

In this paper we present some recent work performed at "Carlo Novero" lab on Quantum Information and Foundations of Quantum Mechanics.Comment: Contribution to III international workshop "Recent advances in Foundations of Quantum Mechanics and Quantum Information. In memory of Carlo Novero

Decisive Search for a Diquark-Antidiquark Meson with Hidden Strangeness

Diquark-antidiquark states are expected to exist as a natural complement of mesons and baryons. Although they were predicted long ago, and some candidates were found experimentally, none has, as yet, been reliably identified. We suggest that the search for the so-called $C(1480)$-meson in reactions such as photoproduction $\gamma N\rightarrow\phi\pi N$ and $K N \rightarrow \phi \pi \Lambda$ should provide a decisive way to settle this issue. Estimates of the cross sections are given using present experimental information on the C-meson and assuming its diquark-antidiquark structure. Sizable cross sections are predicted (of the order of 0.1 $\mu$b for photoproduction and of the order of 0.1 mb for $KN$ at the maximum with an insignificant background). Failure to find this kind of signal would imply that the C-meson is {\it not} a diquark-antidiquark state.Comment: 9 pages in LATex + 6 figs. (available from authers upon request), IUHET-269/9

New analytic unitarization schemes

We consider two well-known classes of unitarization of Born amplitudes of hadron elastic scattering. The standard class, which saturates at the black disk limit includes the standard eikonal representation, while the other class, which goes beyond the black-disk limit to reach the full unitarity circle, includes the U matrix. It is shown that the basic properties of these schemes are independent of the functional form used for the unitarisation, and that U matrix and eikonal schemes can be extended to have similar properties. A common form of unitarisation is proposed interpolating between both classes. The correspondence with different nonlinear equations are also briefly examined.Comment: 6 pages, 10 figures, corrected typos, 1 fig. redro