Measurement of ionization loss of 50 GeV protons in silicon with smoothly tunable up to 1 cm thickness using a single flat detector

Abstract Research of the ionization loss of 50 GeV protons, the path of which in the depleted layer of the silicon detector was smoothly regulated in the range from 0.3 to 10 mm, is presented. In the experiment, we used a flat silicon detector with a fixed thickness of the depleted layer of 300 μm. The smooth regulation of the path was realized due to the variation of the angle between the surface of the detector and the incident proton beam. The comparison of experimental data and theoretical calculations of the ionization loss demonstrates agreement in all range of thicknesses. Results of the research can be used in order to control the angle between the surface of the detector and the incident beam of relativistic particles. Besides, the results can be used in the analysis of data from astrophysical silicon detectors of charged particles if high-energy particles crossed flat detectors at arbitrary angle.

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Multiple electron stripping of heavy ion beams

Laser and Particle Beams ◽

10.1017/s0263034602204036 ◽

2002 ◽

Vol 20 (4) ◽

pp. 551-554 ◽

Cited By ~ 18

Author(s):

D. MUELLER ◽

L. GRISHAM ◽

I. KAGANOVICH ◽

R.L. WATSON ◽

V. HORVAT ◽

...

Keyword(s):

Charge State ◽

High Energy Physics ◽

Theoretical Calculations ◽

Fusion Energy ◽

Incident Beam ◽

Heavy Ion ◽

High Energy ◽

Ion Beams ◽

Target Chamber ◽

Wide Range

One approach being explored as a route to practical fusion energy uses heavy ion beams focused on an indirect drive target. Such beams will lose electrons while passing through background gas in the target chamber, and therefore it is necessary to assess the rate at which the charge state of the incident beam evolves on the way to the target. Accelerators designed primarily for nuclear physics or high energy physics experiments utilize ion sources that generate highly stripped ions in order to achieve high energies economically. As a result, accelerators capable of producing heavy ion beams of 10 to 40 MeV/amu with charge state 1 currently do not exist. Hence, the stripping cross sections used to model the performance of heavy ion fusion driver beams have, up to now, been based on theoretical calculations. We have investigated experimentally the stripping of 3.4 MeV/amu Kr+7 and Xe+11 in N2; 10.2 MeV/amu Ar+6 in He, N2, Ar, and Xe; 19 MeV/amu Ar+8 in He, N2, Ar, and Xe; 30 MeV He+1 in He, N2, Ar, and Xe; and 38 MeV/amu N+6 in He, N2, Ar, and Xe. The results of these measurements are compared with the theoretical calculations to assess their applicability over a wide range of parameters.

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Uv Galaxies

Highlights of Astronomy ◽

10.1017/s1539299600005463 ◽

1983 ◽

Vol 6 ◽

pp. 459-466 ◽

Cited By ~ 2

Author(s):

E. Ye Khachikian

Keyword(s):

Absolute Magnitude ◽

High Energy ◽

List Type ◽

Type Number ◽

Nuclear Region ◽

Continuous Emission ◽

Radio Halo ◽

High Energy Particles ◽

Relativistic Particles

The systematical statement of the concept of the activity of the nuclei of galaxies was first made public by Ambartsumian about 25 years ago (Ambartsumian 1958, 1962, 1965). Since 1965 he has been advancing and developing the idea of the basic role of the nuclei of galaxies in their life and evolution.According to Ambartsumian the “activity” of the nuclei of galaxies manifests itself mainly in the following forms: 1.Outflow of ordinary gas matter (in form of jets or clouds) from the nuclear region at the velocity of up to hundreds of kilometres per second.2.Continuous emission of the flux of relativistic particles or other agents, producing high energy particles, as a result of which a radio halo may form around the nucleus.3.Eruptive ejections of gas matter (M82 type).4.Eruptive ejections of concentrations of relativistic plasma (NGC 4486, 5128, etc.)I should like to emphasize on the form of activity which says: 5.Ejection of compact blue condensations with an absolute magnitude of the order of luminosity of dward galaxies (NGC 3561, IC 1182). Here the division of the nucleus into two or more comparable componentsis also presumed; initiating the formation of multiple galaxies.

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Silicon detectors with 5 ≃m spatial resolution for high energy particles

Nuclear Instruments and Methods in Physics Research ◽

10.1016/0167-5087(83)90138-2 ◽

1983 ◽

Vol 217 (1-2) ◽

pp. 224-228 ◽

Cited By ~ 17

Author(s):

E. Belau ◽

J. Kemmer ◽

R. Klanner ◽

U. Kötz ◽

G. Lutz ◽

...

Keyword(s):

Spatial Resolution ◽

High Energy ◽

Silicon Detectors ◽

High Energy Particles

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Particle Acceleration by Pulsars

Symposium - International Astronomical Union ◽

10.1017/s007418090007457x ◽

1981 ◽

Vol 94 ◽

pp. 175-204 ◽

Cited By ~ 2

Author(s):

Jonathan Arons

Keyword(s):

High Energy ◽

Rotational Energy ◽

Pair Creation ◽

X Ray ◽

Current State ◽

Very High Energy ◽

Γ Ray ◽

High Energy Particles ◽

Relativistic Particles ◽

Very High

The evidence that pulsars accelerate relativistic particles is reviewed, with emphasis on the γ-ray observations. The current state of knowledge of acceleration in strong waves is summarized, with emphasis on the inability of consistent theories to accelerate very high energy particles without converting too much energy into high energy photons. The state of viable models for pair creation by pulsars is summarized, with the conclusion that pulsars very likely lose rotational energy in winds instead of in superluminous strong waves. The relation of the pair creation models to γ-ray observations and to soft X-ray observations of pulsars is outlined, with the conclusion that energetically viable models may exist, but none have yet yielded useful agreement with the extant data. Some paths for overcoming present problems are discussed.

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High-energy particles from SN-explosions near the Galactic center

Proceedings of the International Astronomical Union ◽

10.1017/s1743921314001124 ◽

2013 ◽

Vol 9 (S303) ◽

pp. 454-455

Author(s):

Ernst A. Dorfi ◽

Daniel Steiner

Keyword(s):

Shock Waves ◽

Galactic Center ◽

Galactic Plane ◽

Strong Shock ◽

High Energy ◽

Pressure Gradients ◽

Dependent Mass ◽

High Energy Particles ◽

Relativistic Particles ◽

Compact Cluster

AbstractSeveral supernovae exploding in a compact cluster of massive stars generate a galactic outflow with embedded shock waves. Based on numerical simulations for an expanding superbubble above the Galactic center we find that these individual waves generated by the repeated SN-explosions, interact with each other and finally coalesce into a single strong shock at a distance of 5 kpc above the Galactic plane at about 5 ċ 106 years after outbreak. The resulting shock with a Mach number M ≃ 10 propagates up to 100 kpc in less than 108 years. The time-dependent mass an energy loss out of the superbubble affects the further evolution of the outflow. In such long lasting shock waves energetic particles can be accelerated above the knee of 1015 eV already near the galactic plane by a first-order Fermi-mechanism. The additional pressure gradients from such cosmic rays lead to further accelerations of the galactic outflow since these ultra-relativistic particles suffer less from adiabatic losses than the thermal gas.

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Kinematic Approximations in TED and RHEED Analysis of Reconstructed Surfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100135587 ◽

1990 ◽

Vol 48 (2) ◽

pp. 396-397

Author(s):

L. -M. Peng ◽

M. J. Whelan

Keyword(s):

Electron Diffraction ◽

Kinematic Analysis ◽

Incident Beam ◽

High Energy ◽

Energy Electron ◽

Great Success ◽

High Energy Electron ◽

Kinematic Approximation ◽

Reconstructed Surfaces

In recent years there has been a trend in the structure determination of reconstructed surfaces to use high energy electron diffraction techniques, and to employ a kinematic approximation in analyzing the intensities of surface superlattice reflections. Experimentally this is motivated by the great success of the determination of the dimer adatom stacking fault (DAS) structure of the Si(111) 7 × 7 reconstructed surface.While in the case of transmission electron diffraction (TED) the validity of the kinematic approximation has been examined by using multislice calculations for Si and certain incident beam directions, far less has been done in the reflection high energy electron diffraction (RHEED) case. In this paper we aim to provide a thorough Bloch wave analysis of the various diffraction processes involved, and to set criteria on the validity for the kinematic analysis of the intensities of the surface superlattice reflections.The validity of the kinematic analysis, being common to both the TED and RHEED case, relies primarily on two underlying observations, namely (l)the surface superlattice scattering in the selvedge is kinematically dominating, and (2)the superlattice diffracted beams are uncoupled from the fundamental diffracted beams within the bulk.

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