arXiv subjects

M. Errico

Publications and source records attributed to M. Errico.

5 recordsLinked to original sources

arXiv2008

Magnetic Monopole Search at high altitude with the SLIM experiment

The SLIM experiment was a large array of nuclear track detectors located at the Chacaltaya high altitude Laboratory (5230 m a.s.l.). The detector was in particular sensitive to Intermediate Mass Magnetic Monopoles, with masses 10^5 < M <10^{12} GeV. From the analysis of the full detector exposed for more than 4 years a flux upper limit of 1.3 x 10^{-15} cm^{-2} s^{-1} sr^{-1} for downgoing fast Intermediate Mass Monopoles was established at the 90% C.L.

hep-ex↗

arXiv2008

Results of the Search for Strange Quark Matter and Q-balls with the SLIM Experiment

The SLIM experiment at the Chacaltaya high altitude laboratory was sensitive to nuclearites and Q-balls, which could be present in the cosmic radiation as possible Dark Matter components. It was sensitive also to strangelets, i.e. small lumps of Strange Quark Matter predicted at such altitudes by various phenomenological models. The analysis of 427 m^2 of Nuclear Track Detectors exposed for 4.22 years showed no candidate event. New upper limits on the flux of downgoing nuclearites and Q-balls at the 90% C.L. were established. The null result also restricts models for strangelets propagation through the Earth atmosphere.

hep-ex↗

arXiv2008

The treatment and rejection of two "strange" candidate events in the SLIM experiment

During the analysis of the CR39 Nuclear Track Detectors (NTDs) of the SLIM experiment exposed at the high altitude lab of Chacaltaya (Bolivia) we observed a sequence of puzzling etch-pits. We made a detailed investigation of all the CR39 and Makrofol detectors in the same stack and in all the stacks around the candidate event. We found a second puzzling sequence of etch-pits (plus some single etch-pits). The analysis of this configuration was important because we were searching for rare particles (Magnetic Monopoles, Nuclearites, Q-balls) in the cosmic radiation. Thus we analyzed in detail the evolution with increasing etching time of the etch-pits. We concluded that the two sequences of the etch-pits (and some other background etch-pits) may have originated from a rare manufacture malfunctioning which involved 1 m^2 of produced CR39.

hep-ex↗

arXiv2006

Nuclear Track Detectors for Environmental Studies and Radiation Monitoring

Several improvements were made for Nuclear Track Detectors (NTDs) used for environmental studies and for particle searches. A new method was used to determine the bulk etch rate of CR39 and Makrofol NTDs. It is based on the simultaneous measurement of the diameter and of the height of etch-pit cones caused by relativistic heavy ions (158 A GeV Pb(82+) and In(49+) ions) and their fragments. The use of alcohol in the etching solution improves the surface quality of NTDs and it raises their thresholds. The detectors were used for the determination of nuclear fragmentation cross sections of Iron and Silicon ions of 1.0 and 0.41 GeV/nucleon. These measurements are important for the determination of doses in hadron therapy and for doses received by astronauts. The detectors were also used in the search of massive particles in the cosmic radiation, for the determination of the mass spectrum of cosmic rays and for the evaluation of Po(210) alpha decay and of natural radon concentrations.

physics.ins-det↗

arXiv2006

Nuclear Track Detectors for Particle Searches

In this paper we report a search for intermediate mass magnetic monopoles and nuclearites using CR39 and Makrofol Nuclear Track Detectors (NTDs) of the SLIM large area experiment, 440 m^2 exposed at the high altitude laboratory of Chacaltaya (Bolivia) and about 100 m^2 at Koksil, Himalaya (Pakistan). We discuss the new chemical etching and improved analysis of the SLIM CR39 sheets. Preliminary limits are based on 316 $m^2$ of CR39 NTDs exposed for 3.9 y.

physics.ins-det↗