The cosmic-ray spectral modulation above 2 GV. IV. — The influence on the attenuation coefficient of the nucleonic component

Results are presented of cosmic ray measurements taken at sea level during 1954–55 from the Arctic to the Antarctic. The equipment consisted of a neutron monitor and a meson telescope. Latitude effects of 1.77 for the nucleonic component and 1.15 for the meson component were measured. The longitude effect at the equator was much less than expected on the basis of the geomagnetic eccentric dipole and the longitude effect at intermediate northern latitudes shows that the longitude of the effective eccentric dipole is considerably west of that of the geomagnetic eccentric dipole. In a previous paper by the same authors, the positions of the equatorial minima were combined with other published cosmic ray measurements to calculate a new cosmic ray geomagnetic equator. In this paper new coordinates are derived on the assumption that these equatorial coordinates apply to a new eccentric dipole, and, therefore, that the equatorial coordinates may be extended to high latitudes. When the complete results are plotted on these coordinates, it is found that an eccentric dipole representation of the earth's magnetic field is inconsistent with the combined observations at all latitudes.

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A Survey of the Cosmic-Ray Nucleonic Component along 145° East Longitude using an Airborne Monitor

Nature ◽

10.1038/1811155a0 ◽

1958 ◽

Vol 181 (4616) ◽

pp. 1155-1156 ◽

Cited By ~ 6

Author(s):

J. R. STOREY ◽

A. G. FENTON ◽

K. G. MCCRACKEN

Keyword(s):

Cosmic Ray ◽

Nucleonic Component

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Critique of successive differencing method of regression analysis

Canadian Journal of Physics ◽

10.1139/p68-418 ◽

1968 ◽

Vol 46 (10) ◽

pp. S1061-S1063

Author(s):

Mario Iona ◽

Michael Wiskerchen

Keyword(s):

Time Dependence ◽

Linear Time ◽

Cosmic Ray ◽

Maximum Effect ◽

Regression Techniques ◽

Nucleonic Component ◽

Slope Error ◽

The Difference ◽

Mathematical Foundations ◽

Simulated Time

Various regression techniques have been proposed to calculate barometric coefficients from time-varying cosmic rays recorded by neutron monitors. One of these, the successive differencing method, was carefully examined by applying the technique to simulated time-dependent and time-independent cosmic-ray data and also by investigating the mathematical foundations of the technique. When applying the successive differencing method to time-independent data, the slope and slope error values were found to be dependent on the order in which the data appeared. By ordering the data from highest to lowest pressure, the slope error increased markedly. This falsification of the slope can be shown to be due to improper weighting of the differenced data. Calculations have also been performed to show that the successive differencing method, when applied to intensities containing a linear time dependence, produces a regression slope which retains a time dependence proportional to the difference between the first and last pressure values. The falsification of the slope due to improper weighting of the differenced data can be very much larger than the maximum effect of any reasonable time variation of the nucleonic component.

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A WORLD-WIDE STUDY OF THE DAILY VARIATION OF THE NUCLEONIC COMPONENT OF COSMIC RAYS

Canadian Journal of Physics ◽

10.1139/p60-111 ◽

1960 ◽

Vol 38 (8) ◽

pp. 1011-1026 ◽

Cited By ~ 10

Author(s):

J. Katzman ◽

D. Venkatesan

Keyword(s):

Diurnal Variation ◽

Phase Angle ◽

World Wide ◽

Pressure Effect ◽

Cosmic Ray ◽

Mean Amplitude ◽

Short Term ◽

Nucleonic Component ◽

The Mean ◽

Considerable Spread

The semidiurnal component of the nucleonic intensity at Ottawa, Canada, is essentially a pressure effect for the 5-year period, 1955 to 1959. The diurnal variation is composed of the component due to pressure, and a component that may be attributed to an anisotropy of the primary cosmic-ray particles. The results are confirmed by a comparative study of the data from 15 stations between the geomagnetic latitudes 83 °N. and 73 °S.A world-wide barometric coefficient of −0.72% per mb was obtained from the semidiurnal component and this coefficient was used to correct the diurnal component at all the stations. The average corrected diurnal variation during the period of study common to all stations, August 1957 to October 1958, is 0.27% and occurs at 14 h 16 m solar time. There is considerable spread in both amplitude and phase angle amongst the various stations. The root mean square differences from the mean amplitude is ±0.05% and from the mean phase angle is ±10° (40 minutes in time). The difficulty of drawing definite conclusions about the anisotropy from short-term studies of individual stations is pointed out.

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Study of individual pulses at the Antarctic high-altitude neutron monitor DOMC

NMDB@Home 2020 - Cosmic ray studies with neutron detectors ◽

10.38072/2748-3150/p22 ◽

2021 ◽

pp. 173-176

Author(s):

Markus Similä ◽

Stepan Poluianov ◽

Ilya Usoskin

Keyword(s):

Waiting Times ◽

Pulse Height ◽

Cosmic Ray ◽

High Energy ◽

Waiting Time Distribution ◽

High Energy Cosmic Rays ◽

Different Types ◽

Nucleonic Component ◽

Counting Tube ◽

The Antarctic

A pair of neutron monitors (NMs) is installed on the high Central Antarctic plateau, at the Concordia station (3200 m altitude) and measures the nucleonic component of nucleonic-muon-electromagnetic cascades in- duced by high-energy cosmic rays in the atmosphere. The installation includes two NMs: DOMC, a standard mini-NM, and a bare (lead-free) DOMB NM. The newly installed data acquisition (DAQ) system records in- dividual pulses corresponding to mostly neutrons in the detector’s counting tube. Here we analyze different types of pulses and study the distribution of the waiting times between individual pulses as well as the pulse height, recorded by the DOMC NM during a quiet period of January 2020. The distribution appears double- peaked with peaks corresponding to the frequency of individual atmospheric cascades and the intra-cascade variability, respectively. We discuss also the nature of different components contributing to the pulses and se - paration of the signal from noise. It is shown that the waiting-time distribution has distinguished timescales, >30 ms defined by the cosmic-ray induced atmospheric cascades, and < 10 ms reflecting the intra-cascade variability. The new DAQ system allows one to study the development of the atmospheric cascade.

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