scholarly journals Recent developments in cosmic ray physics

2014 ◽  
Vol 256-257 ◽  
pp. 36-47 ◽  
Author(s):  
P. Blasi
Keyword(s):  
Cosmic Ray ◽  
Recent Developments

RECENT DEVELOPMENTS IN LOW BACKGROUND GEIGER–MÜLLER COUNTERS

1956 ◽  
Vol 34 (3) ◽  
pp. 206-213 ◽  
Author(s):  
W. E. Grummitt ◽  
R. M. Brown ◽  
A. J. Cruikshank ◽  
I. L. Fowler
Keyword(s):  
Construction Materials ◽  
Cosmic Ray ◽  
Low Background ◽  
Recent Developments ◽  
Coincidence Counter ◽  
Normal Background

G–M counting assemblies have been constructed which give dependable low background operation in routine use. Possible construction materials have been examined in detail for radioactive content in an effort to achieve minimum inherent activity in the assembly. The cosmic ray component of the normal background has been eliminated by an anticoincidence arrangement. Increased reliability of the system is obtained through (a) use of a multiple anode anti-coincidence counter in place of a bundle of tubes, (b) use of an electronic quench on both sample and shielding counters, and (c) operation of the assembly as flow counters in tandem. In the best arrangement to date a copper counter with a polystyrene seal gives a background of 0.9 counts per minute.

scholarly journals Muon radiography for exploration of Mars geology

2012 ◽  
Vol 2 (2) ◽  
pp. 829-853
Author(s):  
S. Kedar ◽  
H. K. M. Tanaka ◽  
C. J. Naudet ◽  
C. E. Jones ◽  
J. P. Plaut ◽  
...  
Keyword(s):  
Low Power ◽  
Large Scale ◽  
Cosmic Ray ◽  
Passive Imaging ◽  
Geological Structures ◽  
Minimal Impact ◽  
Naturally Occurring ◽  
Muon Radiography ◽  
Recent Developments ◽  
Muon Production

Abstract. Muon radiography is a technique that uses naturally occurring showers of muons (penetrating particles generated by cosmic rays) to image the interior of large scale geological structures in much the same way as standard X-ray radiography is used to image the interior of smaller objects. Recent developments and application of the technique to terrestrial volcanoes have demonstrated that a low-power, passive muon detector can peer deep into geological structures up to several kilometers in size, and provide crisp density profile images of their interior at ten meter scale resolution. Preliminary estimates of muon production on Mars indicate that the near horizontal Martian muon flux, which could be used for muon radiography, is as strong or stronger than that on Earth, making the technique suitable for exploration of numerous high priority geological targets on Mars. The high spatial resolution of muon radiography also makes the technique particularly suited for the discovery and delineation of Martian caverns, the most likely planetary environment for biological activity. As a passive imaging technique, muon radiography uses the perpetually present background cosmic ray radiation as the energy source for probing the interior of structures from the surface of the planet. The passive nature of the measurements provides an opportunity for a low power and low data rate instrument for planetary exploration that could operate as a scientifically valuable primary or secondary instrument in a variety of settings, with minimal impact on the mission's other instruments and operation.

scholarly journals RADIATION STUDIES FOR THE Mu2e EXPERIMENT: A REVIEW

2013 ◽  
Vol 28 (19) ◽  
pp. 1330014 ◽  
Author(s):  
V. S. PRONSKIKH
Keyword(s):  
Peak Power ◽  
Secondary Particle ◽  
Rare Event ◽  
Absorbed Dose ◽  
Cosmic Ray ◽  
Radiation Environment ◽  
Beyond The Standard Model ◽  
The Standard Model ◽  
Water Activation ◽  
Recent Developments

The Mu2e experiment being designed at Fermilab will be searching for a rare event — conversion of muon into electron in the field of a nucleus without emission of neutrinos — observation of which would provide unambiguous evidence for physics beyond the Standard Model, making use of an 8 GeV 8 kW proton beam. As an experiment to be performed at the Intensity Frontier, taking advantage of high-intensity proton beams, the Mu2e experimental setup will be residing in a harsh radiation environment created by secondary particle fluxes. Radiation quantities in different parts of the Mu2e apparatus, such as neutron flux, peak power density, displacements per atom (DPA), absorbed dose, dynamic heat load simulated using the MARS15 code are reviewed in this work. Radiation levels and requirements for Heat and Radiation Shield (HRS), Transport Solenoid (TS), residual dose and decay heat from the Mu2e target, beam dump design, rates in Cosmic Ray Veto (CRV) counters as well as stopping target monitor (STM) are considered. Airflow, surface and ground water activation are estimated. Recent developments in the MARS15 DPA model applied in this work are described, their consequences are discussed.

scholarly journals RECENT DEVELOPMENTS IN ULTRA-HIGH ENERGY NEUTRINO ASTRONOMY

2013 ◽  
Vol 53 (A) ◽  
pp. 750-755
Author(s):  
Peter K. F. Grieder
Keyword(s):  
Cosmic Ray ◽  
High Energy ◽  
Ultrahigh Energy ◽  
Air Showers ◽  
Neutrino Telescopes ◽  
Particle Properties ◽  
Recent Developments ◽  
Air Fluorescence ◽  
Neutrino Astronomy ◽  
Under Construction

We outline the current situation in ultrahigh energy (UHE) cosmic ray physics, pointing out the remaining problems, in particular the puzzle concerning the origin of the primary radiation and the role of neutrino astronomy for locating the sources. Various methods for the detection of UHE neutrinos are briefly described and their merits compared. We give an account of the achievements of the existing optical Cherenkov neutrino telescopes, outline the possibility of using air fluorescence and particle properties of air showers to identify neutrino induced events, and discuss various pioneering experiments employing radio and acoustic detection of extremely energetic neutrinos. The next generation of space, ground and sea based neutrino telescopes now under construction or in the planning phase are listed.

scholarly journals Messengers of the Universe-Cosmic Rays Exploring Supermassive Black Holes

Galaxies ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 2
Author(s):  
Anna Uryson
Keyword(s):  
Black Holes ◽  
Cosmic Rays ◽  
Cosmic Ray ◽  
Supermassive Black Holes ◽  
High Energies ◽  
Recent Developments ◽  
The Universe

Cosmic rays were discovered over one hundred years ago but there are still unsolved problems. One of the hot problems is the origin of cosmic rays of the highest energies. Sources are still unclear and it is neither clear how particles gain ultra-high energies. Possible sources of cosmic rays at the highest energies are supermassive black holes. From this perspective we discuss in a popular form some recent developments in cosmic ray studies along with author’s recent results. The paper also offers materials for further reading.

scholarly journals Cosmic-ray driven dynamo in galaxies

2010 ◽  
Vol 6 (S274) ◽  
pp. 355-360 ◽  
Author(s):  
M. Hanasz ◽  
D. Wóltanski ◽  
K. Kowalik ◽  
H. Kotarba
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Large Scale ◽  
Numerical Models ◽  
Rotation Period ◽  
Cosmic Ray ◽  
Small Scale ◽  
Galactic Rotation ◽  
Large Scale Magnetic Field ◽  
Recent Developments

AbstractWe present recent developments of global galactic-scale numerical models of the Cosmic Ray (CR) driven dynamo, which was originally proposed by Parker (1992). We conduct a series of direct CR+MHD numerical simulations of the dynamics of the interstellar medium (ISM), composed of gas, magnetic fields and CR components. We take into account CRs accelerated in randomly distributed supernova (SN) remnants, and assume that SNe deposit small-scale, randomly oriented, dipolar magnetic fields into the ISM. The amplification timescale of the large-scale magnetic field resulting from the CR-driven dynamo is comparable to the galactic rotation period. The process efficiently converts small-scale magnetic fields of SN-remnants into galactic-scale magnetic fields. The resulting magnetic field structure resembles the X-shaped magnetic fields observed in edge-on galaxies.

STUDYING NEW PHYSICS USING ULTRAHIGH-ENERGY COSMIC-RAY γ-FAMILY DATA

1996 ◽  
Vol 11 (25) ◽  
pp. 2013-2026 ◽  
Author(s):  
Y.D. HE
Keyword(s):  
Event Rate ◽  
Cosmic Ray ◽  
New Physics ◽  
Energy Scale ◽  
Family Data ◽  
Beyond The Standard Model ◽  
Ultrahigh Energy ◽  
Characteristic Energy ◽  
The Standard Model ◽  
Recent Developments

This review discusses some recent developments in the study of ultrahigh-energy interactions using cosmic-ray γ-family data obtained with emulsion chambers at mountain altitudes. The apparent excess of the event rate at large transverse momenta with respect to the prediction based on perturbative QCD indicates new interaction mechanisms at E lab ≃104–105 TeV, an energy regime beyond the reach of existing colliders. To reconcile the data with a compositeness model of quarks, the characteristic energy scale would have to be as low as Λc≤0.1 TeV, in conflict with the lower limit of Λc>1.4 TeV or a possible value of Λc≃1.6 TeV obtained by the CDF experiment at Tevatron. Possible new physics beyond the standard model, together with future experiments at the LHC, are also discussed.

scholarly journals Muon radiography for exploration of Mars geology

2013 ◽  
Vol 2 (1) ◽  
pp. 157-164 ◽  
Author(s):  
S. Kedar ◽  
H. K. M. Tanaka ◽  
C. J. Naudet ◽  
C. E. Jones ◽  
J. P. Plaut ◽  
...  
Keyword(s):  
Low Power ◽  
Large Scale ◽  
Cosmic Ray ◽  
Passive Imaging ◽  
Geological Structures ◽  
Minimal Impact ◽  
Naturally Occurring ◽  
Muon Radiography ◽  
Recent Developments ◽  
Muon Production

Abstract. Muon radiography is a technique that uses naturally occurring showers of muons (penetrating particles generated by cosmic rays) to image the interior of large-scale geological structures in much the same way as standard X-ray radiography is used to image the interior of smaller objects. Recent developments and application of the technique to terrestrial volcanoes have demonstrated that a low-power, passive muon detector can peer deep into geological structures up to several kilometers in size, and provide crisp density profile images of their interior at ten meter scale resolution. Preliminary estimates of muon production on Mars indicate that the near horizontal Martian muon flux, which could be used for muon radiography, is as strong or stronger than that on Earth, making the technique suitable for exploration of numerous high priority geological targets on Mars. The high spatial resolution of muon radiography also makes the technique particularly suited for the discovery and delineation of Martian caverns, the most likely planetary environment for biological activity. As a passive imaging technique, muon radiography uses the perpetually present background cosmic ray radiation as the energy source for probing the interior of structures from the surface of the planet. The passive nature of the measurements provides an opportunity for a low power and low data rate instrument for planetary exploration that could operate as a scientifically valuable primary or secondary instrument in a variety of settings, with minimal impact on the mission's other instruments and operation.

Trends in Electron Energy Loss Spectroscopy

1977 ◽  
Vol 35 ◽  
pp. 228-229
Author(s):  
C. Colliex ◽  
P. Trebbia
Keyword(s):  
Energy Loss ◽  
Electron Energy ◽  
Electron Energy Loss Spectroscopy ◽  
Materials Science ◽  
Analytical Technique ◽  
Recent Developments ◽  
Quantitative Results ◽  
Electron Microscopes ◽  
Electron Energy Loss ◽  
Primary Electrons

The physical foundations for the use of electron energy loss spectroscopy towards analytical purposes, seem now rather well established and have been extensively discussed through recent publications. In this brief review we intend only to mention most recent developments in this field, which became available to our knowledge. We derive also some lines of discussion to define more clearly the limits of this analytical technique in materials science problems.The spectral information carried in both low ( 0<ΔE<100eV ) and high ( >100eV ) energy regions of the loss spectrum, is capable to provide quantitative results. Spectrometers have therefore been designed to work with all kinds of electron microscopes and to cover large energy ranges for the detection of inelastically scattered electrons (for instance the L-edge of molybdenum at 2500eV has been measured by van Zuylen with primary electrons of 80 kV). It is rather easy to fix a post-specimen magnetic optics on a STEM, but Crewe has recently underlined that great care should be devoted to optimize the collecting power and the energy resolution of the whole system.

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