Results of Dark Matter Searches with the MACRO Experiment

The results of dark matter searches with the MACRO experiment are reported. In particular indirect searches for WIMP's and direct searches for supermassive GUT magnetic monopoles are reported together with massive neutrino studies through the measurement of the oscillation induced anomalies in the atmospheric neutrino flux.Comment: Talk given at the 4th Int. Workshop for the Identification of Dark Matter, York (UK) September 200

Relationship lending in a financial turmoil

We investigate whether the shape of relations between banks and firms has had a detectable effect in mitigating the credit contraction that followed Lehman's default in September 2008. Using micro data on a large sample of Italian firms, we analyze the relation between firms' debt concentration and credit availability. We show that firms borrowing from a higher number of banks suffered on average a larger contraction in bank credit and a higher probability of experiencing a reduction in outstanding bank debt. The same results hold for firms diversifying their borrowing, concentrating a smaller proportion with the main bank. The stability of the bank-firm relationship, measured by its duration, also appears to have been of some value in mitigating the credit restriction. Our results also suggest the existence of a different regime in credit supply towards firms experiencing a reduction in outstanding bank debt. If there is a contraction in credit, the decrease is limited if relations are more intense i.e. a lower number of financial institutions from which the firm borrows, more concentrated lending and relations of greater duration. The opposite is true for firms with positive credit growth.relationship lending, financial crisis

Magnetic monopole searches in the cosmic radiation

There has been a big effort in the past twenty years with at least a couple of generations of experiments which searched for supermassive GUT magnetic monopoles in the cosmic radiation. Here a short review of these searches is given, together with a brief description of the theoretical framework and of the detection techniques

Nuclear re-interaction effects in quasi-elastic neutrino nucleus scattering

The quasi-elastic neutrino-nucleus cross section has been calculated by using a Fermi gas model corrected to consider the re-scattering between the emitted nucleon and the rest nucleus. As an example of the relevance of this effect we show results for the muon production cross section on 16O target.Comment: 7 pages, 4 Postscript figures, Contribution to NuInt01 Workshop, KEK, Tsukuba, Japa

Review of Cosmic Ray experiments with underground detectors

The most important underground detectors addressing Cosmic Ray physics are described, with a special emphasis on the description of the used technology.Comment: Invited talk at 6th International Conference on advanced Technology and Particle Physics, Villa Olmo, Como, Italy, October 5-9, 1998, To be published in Nucl. Phys. B, Proc. Supp

Multiscale image analysis applied to gamma/hadron discrimination for VHE gamma-ray astronomy with ARGO-YBJ

Intrinsic differences in the processes involved in the development of electromagnetic and hadronic showers in the atmosphere have been evidenced by means of a careful analysis of the event image given by the ARGO-YBJ detector. The images have been analyzed at different length scales and their multifractal nature has been studied. The use of the multiscale approach together with a properly designed and trained Artificial Neural Network, allowed us to obtain a good gamma/hadron discrimination power. If confirmed by further studies on different event cathegories, this result would allow to nearly double the detector sensitivity to gamma ray sources.Comment: 10 pages, 5 figures, Presented at the "Incontro Nazionale di Astrofisica delle Alte Energie", Rome 15-16 May 200