First results from the ENTOTO neutron monitor: Quantifying the waiting time distribution

R. D. Strauss; Nigussie M. Giday; Ephrem B. Seba; Daniel A. Chekole; Gemechu F. Garuma; Bereket H. Kassa; Teshome Dugassa; C. Diedericks

doi:10.1016/j.asr.2022.05.016

arXiv · 2205.02154

First results from the ENTOTO neutron monitor: Quantifying the waiting time distribution

R. D. Strauss·Nigussie M. Giday·Ephrem B. Seba·Daniel A. Chekole·Gemechu F. Garuma·Bereket H. Kassa·Teshome Dugassa·C. Diedericks

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Abstract

We discuss a newly established neutron monitor station installed at the ENTOTO Observatory Research Center outside of Addis Ababa, Ethiopia. This is a version of a mini-neutron monitor, recently upgraded to detect individual neutrons and able to calculate the waiting time distribution between neutron pulses down to $\sim 1 $ $\mu$s. From the waiting time distribution we define and calculate a new quantity, the correlation ratio, as the ratio of correlated to uncorrelated neutrons measured inside the monitor. We propose that this quantity can, in future, be used as a proxy for spectral index of atmospheric particles incident on the monitor and show that this quantity has a weak pressure dependence. We believe that future measurements from the ENTOTO mini-neutron monitor will contribute towards the understanding of cosmic ray acceleration and transport in the heliosphere.

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R. D. Strauss, Nigussie M. Giday, Ephrem B. Seba, Daniel A. Chekole, Gemechu F. Garuma, Bereket H. Kassa, Teshome Dugassa, C. Diedericks. 2022-05-04. First results from the ENTOTO neutron monitor: Quantifying the waiting time distribution. https://doi.org/10.1016/j.asr.2022.05.016

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