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The NUCLEON-2 experiment is aimed at the investigation of isotope and charge composition of medium, heavy and ultra-heavy ions ( Z 82 ) in the 300 MeV/N - 1 GeV/N energy range. The concept design of HICRS for the NUCLEON-2 satellite cosmic ray experiment is presented. The performed simulation confirms the isotope resolution algorithms and techniques. Argon isotopes’ resolution in the NUCLEON-2 prototype is presented.

In this paper, the goals and scientific tasks of the space experiment “High Energy Rays Observatory” (HERO) are established. The preliminary design of the scientific equipment is presented, the characteristic features of which are its high geometric factor (up to ∼20 m2 sr) and adequate energy measurement resolution (20–30% or better, depending on the type of components). The ionisation tungsten-scintillator calorimeter is used for energy measurement. The total calorimeter weight is equal to 12 tons. The technical characteristics of the equipment permit the direct study of cosmic rays in a wide energy range, including the unexplored region of 1015–1016 eV. The current status of the space experiment is discussed. Currently, the HERO project is in its pre-R&D phase. The launch of the satellite is planned for between 2025 and 2030.

The NUCLEON experiment aims to study chemical composition and energy spectra of galactic cosmic rays for nuclei charges Z = 1 − 30 and energies 10 11 − 10 15 eV. The research is conducted with the help of the NUCLEON scientific equipment installed on the Russian satellite “Resurs-P” No. 2 as an additional payload. This article describes the results of the first year of the space experiment NUCLEON, including methodological features of data acquisition mode setup, evaluation of the equipment’s performance and methods it provides, as well as preliminary results of data analysis.

The ratios of heavy nuclei from Sulfur (Z=16) to Chromium (Z=24) fluxes to the flux of iron nuclei were measured recently in the ATIC-2 experiment. These ratios were the decreasing functions of energy from 5 GeV/n to approximately 50 GeV/n as expected. However, an unexpected sharp upturn in the ratios was observed at energy ∼ 50 GeV/n. In this paper, we revise the data and show that the statistical confidence of the observed upturn in the ATIC data is 99.7% and some additional argumets supporting the phenomenon are presented. A possible cause of the upturn is discussed and it is demonstrated that it can be partially understood within a model of ‘Closed Galaxy with Bubbles’ (CGB). Some features and problems of the CGB model are discussed.

The Advanced Thin Ionization Calorimeter (ATIC) Balloon Experiment had a successful test flight and a science flight in 2000–01 and 2002–03 and an unsuccessful launch in 2005–06 from McMurdo, Antarctica, returning 16 and 19 days of flight data. ATIC is designed to measure the spectra of cosmic rays (protons to iron). The instrument is composed of a Silicon matrix detector followed by a carbon target interleaved with scintillator tracking layers and a segmented BGO calorimeter composed of 320 individual crystals totaling 18 radiation lengths to determine the particle energy. BGO (Bismuth Germanate) is an inorganic scintillation crystal and its light output depends not only on the energy deposited by particles but also on the temperature of the crystal. The temperature of balloon instruments during flight is not constant due to sun angle variations as well as differences in albedo from the ground. The change in output for a given energy deposit in the crystals in response to temperature variations was determined.

The Advanced Thin Ionization Calorimeter (ATIC) experiment is designed to investigate the charge composition and energy spectra of primary cosmic rays over the energy range from about 10(11) to 10(14) eV during Long Duration Balloon (LDB) flights from McMurdo, Antarctica. Currently, analysis from the ATIC-1 test flight and ATIC-2 science flight is underway and preparation for a second science flight is in progress. Charge identification of the incident cosmic ray is accomplished, primarily, by a pixilated Silicon Matrix detector located at the very top of the instrument. While it has been shown that the Silicon Matrix detector provides good charge identification even in the presence of electromagnetic shower backscatter from tile calorimeter, the detector only measures the charge once. In this paper, we examine use of the top scintillator hodoscope detector to provide a second measure of the cosmic ray charge and, thus, improve the ATIC charge identification. (c) 2007 COSPAR. Published by Elsevier Ltd. All rights reserved.

The preliminary energy spectra of heavy nuclei C, O, Ne, Mg, Si, and Fe in the primary cosmic rays measured by the ATIC-2 experiment are presented and compared to previous data and to propagation models. Using previous data to extend the ATIC-2 results for all heavy nuclei to higher energy, the combined spectra can be best fit with diffusion model with weak reacceleration and scattering on random magnetic field with a Kolmogorov spectrum fluctuations becoming dominant at high energy. (c) 2005 COSPAR. Published by Elsevier Ltd. All rights reserved.

The Advanced Thin Ionization Calorimeter (ATIC) balloon-borne experiment is designed to perform cosmic-ray elemental spectra measurement from 50 GeV to 100 TeV for nuclei from hydrogen to iron. These measurements are expected to provide crucial hints about some of the most fundamental questions in astroparticle physics today. ATTIC'S design centers on an 18 radiation length (X(sub Omnicron)) deep bismuth germanate (BGO) calorimeter, preceded by a 0.75 lambda(sub int) graphite target. In September 1999 the ATIC detector was exposed to high-energy beams at CERN's SPS accelerator, within the framework of the development program for the Advanced Cosmic-ray Composition Experiment for the Space Station (ACCESS). In December 2000 - January 2001, ATIC flew on the first of a series of long duration balloon (LDB) flights from McMurdo Station, Antarctica. We present here results from the 1999 beam-tests, including energy resolutions for electrons and protons at several beam energies from 100 GeV to 375 GeV, as well as signal linearity and collection efficiency estimates. We show how these results compare with expectations based on simulations, and their expected impacts on mission performance.

It is supposed that the sequence of the Earths biospheric revolutions obeys the scaling law. An estimation of the duration of the prebiological chemical evolution as (5–7) · 10 9 years is obtained by an extrapolation of the scaling law of the biospheric evolution. The expected scale of time of interstellar prebiological panspermia (� 0.2 · 10 9 yr) is much shorter then the estimated duration of the prebiological chemical evolution. The hypothesis of the long prebiological chemical evolution implies that: (a) the prebiological evolution and the origin of life may be a self-consistent Galaxy process and not a process localized on single planets and (b) life has the same chemical base and the same chirality everywhere in the Galaxy. � 2005 COSPAR. Published by Elsevier Ltd. All rights reserved.

The Advanced Thin Ionization Calorimeter (ATIC) was built for series of long- duration balloon flights in Antarctica. Its main goal is to measure energy spectra of cosmic ray nuclei from protons up to iron nuclei over a wide energy range from 30 GeV up to 100 TeV. The ATIC balloon experiment had its first, test flight that lasted for 16 days from 28 Dec 2000 to 13 Jan 2OO1 around the continent. The ATIC spectrometer consists of a fully active BGO calorimeter, scintillator hodoscopes and a silicon matrix. The silicon matrix, consisting of 4480 pixels, was used as a charge detector in the experiment. About 25 million cosmic ray events were detected during the flight. In the paper, the charge spectrum obtained with the silicon matrix is analyzed.

Long Duration Balloon (LDB) scientific experiments, launched to circumnavigate the south pole over Antarctica, have particular advantages compared to Shuttle or other Low Earth Orbit (LEO) missions in terms of cost, weight, scientific “duty factor” and work force development. The Advanced Thin Ionization Calorimeter (ATIC) cosmic-ray astrophysics experiment is a good example of a university-based project that takes full advantage of current LDB capability. The ATIC experiment is currently being prepared for its first LDB science flight that will investigate the charge composition and energy spectra of primary cosmic-rays over the energy range from about 1010 to 1014 eV. The instrument is built around a fully active, Bismuth–Germanate (BGO) ionization calorimeter to measure the energy deposited by cascades formed by particles interacting in a thick carbon target. A highly segmented silicon matrix, located above the target, provides good incident charge resolution plus rejection of “backscattered” particles from the cascade. Trajectory reconstruction is based on the cascade profile in the BGO calorimeter, plus information from the three pairs of scintillator hodoscope layers in the target section above it. A full evaluation of the experiment was performed during a test flight occurring between 28 December 2000 and 13 January 2001 where ATIC was carried to an altitude of ∼37 km above Antarctica by a ∼850,000 m3 helium filled balloon for one circumnavigation of the continent. All systems behaved well, the detectors performed as expected, >43 GB of engineering and cosmic-ray event data were returned and these data are now undergoing preliminary data analysis. During the coming 2002–2003 Antarctica summer season, we are preparing for an ATIC science flight with ∼15 to 30 days of data collection in the near-space environment of Long Duration Balloon (LDB) float altitudes.

A numerical model of spontaneous decay continuously monitored by a distant detector of emitted particles is constructed. It is shown that there is no quantum Zeno effect in such quantum measurement if the interaction between emitted particle and detector is short-range and the mass of emitted particle is not zero.

The quantum Zeno effect in continuous passive observation of radioactive decay is described starting from the “first principles”. It is argued, that in this case the quantum Zeno effect reduces to the influence of inelastic scattering of decay products in surrounded media to decay constant. A new class of quantum Zeno effects is introduced, which are named as “threshold quantum Zeno effects” (TQZE). It is shown, that TQZE could explain recently discovered deep suppression of the conversion decay of 1/2 + -isomer of uranium-235 in the lattice of silver. TQZE predicts also some new phenomena, which may be observed in the near-threshold behavior of atomic photoionization cross-sections. Possible experimental manifestations of this new phenomena are discussed.