Sidereal Time Periodicity of Cosmic Rays and its Phase Shift

Nature ◽  
1937 ◽  
Vol 139 (3529) ◽  
pp. 1064-1065 ◽  
Author(s):  
J. BARNÓTHY ◽  
M. FORRÓ
Keyword(s):  
Phase Shift ◽  
Cosmic Rays ◽  
Sidereal Time ◽  
Time Periodicity

The North–South Anisotropy and the Radial Density Gradient of Galactic Cosmic Rays at 1 AU

1995 ◽  
Vol 12 (2) ◽  
pp. 153-158 ◽  
Author(s):  
D. L. Hall ◽  
M. L. Duldig ◽  
J. E. Humble
Keyword(s):  
Cosmic Rays ◽  
Diurnal Variation ◽  
Density Gradient ◽  
Cosmic Ray ◽  
Ecliptic Plane ◽  
Galactic Cosmic Rays ◽  
Radial Density ◽  
Sidereal Time ◽  
Direction Parallel ◽  
The North

AbstractThe radial density gradient (Gr) of Galactic cosmic rays in the ecliptic plane points outward from the Sun. This indicates an increasing density of cosmic ray particles beyond the Earth’s orbit. Due to this gradient and the direction of the Sun’s interplanetary magnetic field (IMF) above and below the IMF wavy neutral sheet, there exists an anisotropic flow of cosmic ray particles approximately perpendicular to the ecliptic plane (i.e. in the direction parallel to BIMF × Gr). This effect is called the north–south anisotropy (ξNS) and manifests as a diurnal variation in sidereal time in the particle intensity recorded by a cosmic ray detector. By analysing the yearly averaged sidereal diurnal variation recorded by five neutron monitors and six muon telescopes from 1957 to 1990, we have deduced probable values of the average rigidity spectrum and magnitude of ξNS. Furthermore, we have used determined yearly amplitudes of ξNS to infer the magnitude of Gr for particles with rigidities in excess of 10 GV.

A New Installation for Studying the Sidereal Anisotropy of Cosmic Rays

1982 ◽  
Vol 4 (4) ◽  
pp. 456-458 ◽  
Author(s):  
A. G. Fenton ◽  
K. B Fenton ◽  
J. E. Humble ◽  
R. M. Jacklyn ◽  
A. Vrana ◽  
...  
Keyword(s):  
Cosmic Rays ◽  
Spatial Structure ◽  
Final Analysis ◽  
Galactic Cosmic Rays ◽  
Sidereal Time ◽  
Sidereal Anisotropy ◽  
Small Anisotropy

It is now firmly established that a small anisotropy of the galactic cosmic rays exists, observable from Earth as a variation of intensity in sidereal time. The problem now is to determine more clearly the characteristics of the anisotropy and, in particular, its detailed spatial structure and how it depends upon the energy and composition of the cosmic rays. This is a very difficult task and, in the final analysis, may not be fully achievable from Earth-based observations. The purpose of the present paper is to describe briefly an installation now operating in Tasmania to provide further information on the spatial structure of the anisotropy.

Confirmatory evidence for a sidereal-time dependent neutral component in the cosmic rays

1966 ◽  
Vol 21 (4) ◽  
pp. 478-480 ◽  
Author(s):  
G.L. Buckwalter ◽  
C.L. Cowan ◽  
D.F. Ryan
Keyword(s):  
Cosmic Rays ◽  
Time Dependent ◽  
Neutral Component ◽  
Sidereal Time

Sidereal time variation of high-energy cosmic rays observed by an air Cerenkov telescope

1968 ◽  
Vol 46 (10) ◽  
pp. S607-S610 ◽  
Author(s):  
Y. Sekido ◽  
K. Nagashima ◽  
I. Kondo ◽  
T. Murayama ◽  
H. Okuda ◽  
...  
Keyword(s):  
Cosmic Rays ◽  
Cosmic Ray ◽  
High Energy ◽  
Sidereal Time ◽  
High Energy Cosmic Rays ◽  
Four Seasons ◽  
200 Gev ◽  
The Difference ◽  
Celestial Sphere ◽  
Sidereal Anisotropy

Using the cosmic-ray telescope No. 3 (air Cerenkov telescope) at Nagoya, observations of high-energy (~200 GeV) cosmic rays were continued during the period from February 1964 to March 1966. The observations were made at a fixed zenith angle Z = 60° and at two azimuths A = 72° and 288°. With this setting, the celestial sphere was scanned in the declination band between 25° and 40 °N. Using the difference between the two diurnal vectors observed at 72° (east) and 288° (west), the anisotropy, free from any diurnal variation of meteorological origin, was obtained corresponding to each of four seasons. From these four anisotropy vectors, the solar anisotropy was found to be insignificant, but the sidereal anisotropy was as follows:[Formula: see text]

Object Wave Determination by Single-Sideband Methods

1973 ◽  
Vol 31 ◽  
pp. 266-267
Author(s):  
Kenneth H. Downing ◽  
Benjamin M. Siegel
Keyword(s):  
Phase Shift ◽  
Carbon Films ◽  
Object Wave ◽  
Electron Wave ◽  
Phase Object ◽  
Heavy Atoms ◽  
Single Sideband ◽  
Thin Carbon ◽  
Additional Phase Shift ◽  
Additional Phase

Under the “weak phase object” approximation, the component of the electron wave scattered by an object is phase shifted by π/2 with respect to the unscattered component. This phase shift has been confirmed for thin carbon films by many experiments dealing with image contrast and the contrast transfer theory. There is also an additional phase shift which is a function of the atomic number of the scattering atom. This shift is negligible for light atoms such as carbon, but becomes significant for heavy atoms as used for stains for biological specimens. The light elements are imaged as phase objects, while those atoms scattering with a larger phase shift may be imaged as amplitude objects. There is a great deal of interest in determining the complete object wave, i.e., both the phase and amplitude components of the electron wave leaving the object.

A Many-Beam Technique for Enhanced Resolution of Partial Dislocations

1972 ◽  
Vol 30 ◽  
pp. 646-647
Author(s):  
J. M. Oblak ◽  
B. H. Kear
Keyword(s):  
Phase Shift ◽  
Field Method ◽  
Dark Field ◽  
Bright Field ◽  
Field Technique ◽  
Weak Beam ◽  
Partial Dislocations ◽  
Enhanced Resolution ◽  
Nickel Base ◽  
Beam Technique

The “weak-beam” and systematic many-beam techniques are the currently available methods for resolution of closely spaced dislocations or other inhomogeneities imaged through strain contrast. The former is a dark field technique and image intensities are usually very weak. The latter is a bright field technique, but generally use of a high voltage instrument is required. In what follows a bright field method for obtaining enhanced resolution of partial dislocations at 100 KV accelerating potential will be described.A brief discussion of an application will first be given. A study of intermediate temperature creep processes in commercial nickel-base alloys strengthened by the Ll2 Ni3 Al γ precipitate has suggested that partial dislocations such as those labelled 1 and 2 in Fig. 1(a) are in reality composed of two closely spaced a/6 <112> Shockley partials. Stacking fault contrast, when present, tends to obscure resolution of the partials; thus, conditions for resolution must be chosen such that the phase shift at the fault is 0 or a multiple of 2π.

Observation of surface morphology by reflection electron holography

1989 ◽  
Vol 47 ◽  
pp. 536-537
Author(s):  
N. Osakabe ◽  
J. Endo ◽  
T. Matsuda ◽  
A. Tonomura
Keyword(s):  
Phase Shift ◽  
Surface Morphology ◽  
High Sensitivity ◽  
High Energy ◽  
Path Difference ◽  
Transmission Mode ◽  
Electron Holography ◽  
Dynamical Process ◽  
High Vertical Resolution ◽  
Amplification Technique

Progress in microscopy such as STM and TEM-TED has revealed surface structures in atomic dimension. REM has been used for the observation of surface dynamical process and surface morphology. Recently developed reflection electron holography, which employes REM optics to measure the phase shift of reflected electron, has been proved to be effective for the observation of surface morphology in high vertical resolution ≃ 0.01 Å.The key to the high sensitivity of the method is best shown by comparing the phase shift generation by surface topography with that in transmission mode. Difference in refractive index between vacuum and material Vo/2E≃10-4 owes the phase shift in transmission mode as shownn Fig. 1( a). While geometrical path difference is created in reflection mode( Fig. 1(b) ), which is measured interferometrically using high energy electron beam of wavelength ≃0.01 Å. Together with the phase amplification technique , the vertivcal resolution is expected to be ≤0.01 Å in an ideal case.

Sign in / Sign up

Export Citation Format

Share Document