New experiment for WIMP direct search (NEWSdm)

Dark Matter (DM) search is one of the most significant tasks of modern physics. Direct DM searches are nowadays one of the most fervid research topics with many experimental efforts devoted to the search for nucleus recoils induced by the scattering of Weakly Interactive Massive Particles (WIMP). The new experiment NEWSdm (Nuclear Emulsions for WIMP Search - directional measurement) aimed at direct search for DM particles is based on the technologies of nuclear emulsions combining high spatial resolution and the possibility of creating large mass detectors. Emulsion detectors able to reconstruct the direction of the nuclei recoiling on the WIMP are opening a new frontier to possibly extend DM searches beyond the neutrino background. The detector concept foresees the use of a bulk of nuclear emulsion surrounded with a shield from environmental radioactivity, to be placed on an equatorial telescope in order to cancel out the effect of the Earth rotation keeping the detector at a fixed orientation toward the expected direction of galactic WIMPs. Exploiting directionality would also prove the galactic origin of DM with an unambiguous signal-to-background separation. The use in NEWSdm of fine-grained nuclear emulsions both as target and nanometric tracking device for directional DM searches gives a unique opportunity for a high-significance discovery of galactic DM

One Approach to intellectual image analysis

This study investigated the method of semantic image analysis by using a set of neuron-like detectors of foreground objects. This method is intended to find different types of foreground objects and to determine properties of these objects. As a result of semantic analysis the semantic descriptor of the image is created. The descriptor is a set of foreground objects of the image and a set of properties for each object. The distance between images is defined as distance between their semantic descriptors. Using the concept of distance between images, “semantically similarity” between images or videos is defined

One Approach to intellectual image analysis

This study investigated the method of semantic image analysis by using a set of neuron-like detectors of foreground objects. This method is intended to find different types of foreground objects and to determine properties of these objects. As a result of semantic analysis the semantic descriptor of the image is created. The descriptor is a set of foreground objects of the image and a set of properties for each object. The distance between images is defined as distance between their semantic descriptors. Using the concept of distance between images, “semantically similarity” between images or videos is defined

Low and High Energy Modeling in Geant4

Four of the most-used Geant4 hadronic models, the Quark-gluon string, Bertini-style cascade, Binary cascade and Chiral Invariant Phase Space, are discussed. These models cover high, medium and low energies, respectively, and represent a more theoretical approach to simulating hadronic interactions than do the Low Energy and High Energy Parameterized models. The four models together do not yet cover all particles for all energies, so the Low Energy and High Energy Parameterized models, among others, are used to fill the gaps.The validity range in energy and particle type of each model is presented, as is a discussion of the models' distinguishing features. The main modeling stages are also described qualitatively and areas for improvement are pointed out for each model

Validation of hadronic models in GEANT4

Geant4 is a software toolkit for the simulation of the passage of particles through matter. It has abundant hadronic models from thermal neutron interactions to ultra relativistic hadrons. An overview of validations in Geant4 hadronic physics is presented based on thin-target measurements. In most cases, good agreement is available between Monte Carlo prediction and experimental data; however, several problems have been detected which require some improvement in the models

Experiments on muon radiography with emulsion track detectors

Muon radiography is a method of study the internal structure of large natural and industrial objects based on sensing an object with a flux of cosmic muons with their subsequent registration and analysis of the pattern of their dispersion, or conplete (or partial) absorption. The Lebedev Physical Institute of the Russian Academy of Sciences and the Skobeltsyn Institute of Nuclear Physics of Moscow State University have started a series of muon radiography experiments with nuclear emulsion detectors. As a result, the optimal conditions for experiment arrangement have been determined, algorithms of data processing have been worked out, and peculiarities of the method have been ultimately investigated

Experiments on muon radiography with emulsion track detectors

Muon radiography is a method of study the internal structure of large natural and industrial objects based on sensing an object with a flux of cosmic muons with their subsequent registration and analysis of the pattern of their dispersion, or conplete (or partial) absorption. The Lebedev Physical Institute of the Russian Academy of Sciences and the Skobeltsyn Institute of Nuclear Physics of Moscow State University have started a series of muon radiography experiments with nuclear emulsion detectors. As a result, the optimal conditions for experiment arrangement have been determined, algorithms of data processing have been worked out, and peculiarities of the method have been ultimately investigated

CHARGE SPECTRUM OF HEAVY AND SUPERHEAVY COMPONENTS OF GALACTIC COSMIC RAYS: RESULTS OF THE OLIMPIYA EXPERIMENT

The aim of the OLIMPIYA experiment is to search for and identify traces of heavy and superheavy nuclei of galactic cosmic rays (GCR) in olivine crystals from stony–iron meteorites serving as nuclear track detectors. The method is based on layer-by-layer grinding and etching of particle tracks in these crystals. Unlike the techniques of other authors, this annealing-free method uses two parameters: the etching rate along the track (V etch) and the total track length (L), to identify charge Z of a projectile. A series of irradiations with different swift heavy ions at the accelerator facilities of GSI (Darmstadt) and IMP (Lanzhou) were performed in order to determine and calibrate the dependence of projectile charge on V etch and L. To date, one of the most essential results of the experiment is the obtained charge spectrum of GCR nuclei within the range of Z > 40, based on about 11.6 thousand processed tracks. As the result of data processing, 384 nuclei with charges Z ≥ 75 have been identified, including 10 nuclei identified as actinides (90 < Z < 103). Three tracks were identified to be produced by nuclei with charges 113 < Z < 129. Such nuclei may be part of the Island of Stability of transfermium elements