Search for supermassive magnetic monopoles with the MACRO detector at the gran sasso laboratory

We present the results of the search for supermassive magnetic monopoles with the MACRO experiment. Our detector is equipped with three independent subdetectors (liquid scintillation counters, limited streamer tubes and nuclear track detectors), operating in different ranges of monopole velocity. In several years of data taking no candidates were found; the present flux upper limits are the level of half the Parker Bound for β > 10⁻⁴; for 10⁻⁴ < β < 5 × 10⁻² the limit is the best existing.     

Search for magnetic monopoles with the nuclear track detector of the MACRO experiment at gran SASSO

In this paper the limits are presented which were obtained by the search for magnetic monopoles using the MACRO track-etch subdetector as a stand alone detector. We compare the flux upper limit for g = g_D monopoles to other limits obtained by different subdetectors of MACRO, till August 1, 1995, when the construction of the apparatus was completed. The global MACRO monopole limit is compared with other limits from different experiments.     

Search for GUT magnetic monopoles and nuclearites with the MACRO experiment

We present the final results obtained by the MACRO experiment in the search for GUT magnetic monopoles and nuclearites. Several searches were performed with different subdetectors, i.e. scintillation counters, limited streamer tubes and nuclear track detectors. No magnetic monopole or nuclearite candidates were found. The MACRO upper limit to the local flux of GUT magnetic monopoles is at the level of 1.4×10⁻¹⁶ cm⁻² s⁻¹ sr⁻¹.     

Search for nucleon decays induced by GUT magnetic monopoles with the MACRO experiment

The interaction of a Grand Unification Magnetic Monopole with a nucleon can lead to a barion-number violating process in which the nucleon decays into a lepton and one or more mesons (catalysis of nucleon decay). In this paper we report an experimental study of the effects of a catalysis process in the MACRO detector. Using a dedicated analysis we obtain new magnetic monopole (MM) flux upper limits at the level of for , based on the search for catalysis events in the MACRO data. We also analyze the dependence of the MM flux limit on the catalysis cross section. Received: 2 August 2002 / Published online: 25 October 2002     

Search for stellar gravitational collapses with the MACRO detector

We present the final results of the search for stellar gravitational collapses obtained by the MACRO experiment. The detector was active for a stellar collapse search for more than 11 years and it was sensitive to collapses occurring all over in our galaxy for 8.6 years. A real time system for a prompt recognition of neutrino bursts was developed and was operating on-line for almost the whole life of the experiment. No signal compatible with a neutrino burst from a galactic supernova was observed.Received: 18 February 2003, Revised: 25 March 2004, Published online: 14 September 2004     

Detection of magnetic monopoles with the ANTARES detector

The ANTARES Collaboration is constructing a neutrino telescope on the bottom of the Mediterranean Sea. The main goal of ANTARES is to detect high-energy cosmic neutrinos. The detection principle relies on the observation of Čerenkov light emitted by neutrino-induced muons. It is shown that this type of detector is also able to detect exotic particles such as magnetic monopoles. Above the Čerenkov limit, monopoles can be detected because of the emission of large amounts of direct Čerenkov light. Monopoles are also detectable below the Čerenkov limit through the production of δ rays, which in turn emit Čerenkov light. The development of a software trigger for ANTARES designed for monopole detection is presented. A simulation of the δ-ray-induced and direct Čerenkov light emission by monopoles has been made and used to study the trigger efficiency for the detection of monopoles. Techniques to suppress background at the trigger level are presented, and plans for the future are discussed. for the ANTARES Collaboration The text was submitted by the author in English.     

Search for massive rare particles with the MACRO track-etch detector at Gran Sasso

Searches for massive penetrating particles in the cosmic radiation have been performed with the MACRO nuclear track detector used as a “stand alone” detector. The complete experimental procedure is presented. In absence of candidates, updated estimates of the flux upper limits both for the CR-39 “stand alone” detector and for the global MACRO detector are presented for magnetic monopoles, nuclearites and charged Q-balls.     

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 CR-39 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 CR-39 and Makrofol and the analysis of a first sample of the exposed detector.     

Search for neutrino-produced magnetic monopoles in a bubble chamber exposure

J. Schwinger has suggested that magnetically charged particles could be produced via a magnetically charged intermediate boson process similar to the mechanism sometimes envisioned for double muon production by neutrinos. A search for magnetic monopole production by neutrinos has been made by reexamining the CERN heavy liquid bubble chamber pictures obtained during the neutrino exposures of 1963 and 1967. Five different searches were made for events which contained a free monopole with and without target nucleus excitation, and for bound monopoles which deexcited by photon emission. No events were found. Neutrino monopole production cross-section limits are given.     

Search for magnetic monopoles in proton-antiproton interactions at 540 GeV cm energy

A search for magnetic monopoles hass beenpursued at the proton-antiproton collider at CERN, with plastic detectors. No candidates were found. Limits for the production cross section of such objects are given.     

Passive infrared detector used for detection of very slowly moving of crawling people

The paper presents construction and principle of operation of passive IR detectors (PIR detectors) of a large detection range. Important virtue of these detectors is highly efficient detection of slowly moving or crawling people. The described here PIR detector detects crawling people at the distance of 140 m. To ensure high probability of detection of slowly moving objects, new method of signals analysis was applied. On the basis of the carried out real-time measurements, both probability of detection and false alarms were determined.     

Nuclearite search with the MACRO detector at Gran Sasso

In this paper we present the results of a search for nuclearites in the penetrating cosmic radiation using the scintillator and track-etch subdetectors of the MACRO apparatus. The analyses cover the range at the detector depth (3700 {\rm hg/cm^2}) ; for the flux limit is for an isotropic flux of nuclearites, and twice this value for a flux of downgoing nuclearites. Received: 4 May 1999 / Published online: 25 February 2000     

A slowly moving particle in a two-dimensional magnetic field

We consider the behavior of a slowly moving classical point particle in a magnetic field in two dimensions, and show that, although energy conservation would permit the particle to escape to infinity, it in fact does not escape but is permanently trapped in the field. For any given magnetic field, this is true for particles of slow enough velocity. For such motion the magnetic flux enclosed by the Larmor orbits is an adiabatic invariant. Our results may be described by saying the deviations from conservation of this invariant are not cumulative but remain bounded over arbitrary time intervals, and are small if the velocity is small.