Searcharxiv⌕ Search

arXiv subjects

V. Togo

Publications and source records attributed to V. Togo.

43 records · Page 3Linked to original sources

Search for exotic contributions to atmospheric neutrino oscillations

The energy spectrum of neutrino-induced upward-going muons in MACRO was analysed in terms of relativity principles violating effects, keeping standard mass-induced atmospheric neutrino oscillations as the dominant effect. The data disfavor these possibilities even at a sub-dominant level; stringent 90% C.L. limits are placed on the Lorentz invariance violation parameter $|Δv| < 6 \times 10^{-24}$ at $\sin 2θ_v$ = 0 and $|Δv| < 2.5 ÷5 \times 10^{-26}$ at $\sin 2θ_v$ = $\pm$1. The limits can be re-interpreted as bounds on the Equivalence Principle violation parameters.

hep-ex↗

Search for nuclearites with the SLIM detector

We discuss the properties of cosmic ray nuclearites, from the point of view of their search with large nuclear track detector arrays exposed at different altitudes, in particular with the SLIM experiment at the Chacaltaya high altitude lab (5290 m a.s.l.). We present calculations concerning their propagation in the Earth atmosphere and discuss their possible detection with CR39 and Makrofol nuclear track detectors.

hep-ex↗

Search for a Lorentz invariance violation contribution in atmospheric neutrino oscillations using MACRO data

Neutrino-induced upward-going muons in MACRO have been analysed in terms of relativity principles violating effects, keeping standard mass-induced atmospheric neutrino oscillations as the dominant source of nu_mu -> nu_tau transitions. The data disfavor these exotic possibilities even at a sub-dominant level, and stringent 90% C.L. limits are placed on the Lorentz invariance violation parameter |Delta v| < 6 * 10^(-24) at sin2theta_v = 0 and |Delta v| < 2.5--5 * 10^(-26) at sin2theta_v = +/-1. These limits can also be re-interpreted as upper bounds on the parameters describing violation of the Equivalence Principle.

hep-ex↗

Search for Intermediate Mass Magnetic Monopoles and Nuclearites with the SLIM experiment

SLIM is a large area experiment (440 m2) installed at the Chacaltaya cosmic ray laboratory since 2001, and about 100 m2 at Koksil, Himalaya, since 2003. It is devoted to the search for intermediate mass magnetic monopoles (107-1013 GeV/c2) and nuclearites in the cosmic radiation using stacks of CR39 and Makrofol nuclear track detectors. In four years of operation it will reach a sensitivity to a flux of about 10-15 cm-2 s-1 sr-1. We present the results of the calibration of CR39 and Makrofol and the analysis of a first sample of the exposed detector.

hep-ex↗

Time correlations of high energy muons in an underground detector

We present the result of a search for correlations in the arrival times of high energy muons collected from 1995 till 2000 with the streamer tube system of the complete MACRO detector at the underground Gran Sasso Lab. Large samples of single muons (8.6 million), double muons (0.46 million) and multiple muons with multiplicities from 3 to 6 (0.08 million) were selected. These samples were used to search for time correlations of cosmic ray particles coming from the whole upper hemisphere or from selected space cones. The results of our analyses confirm with high statistics a random arrival time distribution of high energy cosmic rays.

astro-ph↗

Magnetic monopole bibliography

We present a bibliography compilation on magnetic monopoles updated to include references till the end of year 1999. It is intended to contain nearly all the experimental papers on the subject and only the theoretical papers which have some specific experimental implications.

hep-ex↗