Measuring single and multiple atmospheric secondary particles from cosmic rays using cross-counter neutron time delay distributions from the Princess Sirindhorn Neutron Monitor
Warit Mitthumsiri*,1, Alejandro Sáiz 1, David Ruffolo 1,2, Paul Evenson 3, Pierre-Simon Mangeard 3, Waraporn Nuntiyakul 4,2
1 Department of Physics, Faculty of Science, Mahidol University, Bangkok 10400, Thailand
2 National Astronomical Research Institute of Thailand (NARIT), Chiang Mai 50180, Thailand
3 Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, DE 19716, USA
4 Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand
* Presenting author (warit.mit@mahidol.ac.th)
The Princess Sirindhorn Neutron Monitor in Thailand had its electronics upgraded in 2015 for absolute timing capability across its 18 counter tubes. This has enabled us to record the distributions of time delay between two successive counts in any pair of tubes and deduce the overall associations of the detected counts. Analyzing results from measurements and simulations, we find that associated counts between two nearby tubes (no more than 4 tubes apart) are dominated by a single atmospheric secondary interacting within the monitor, while the associated counts between two tubes with large separations (more than 4 tubes apart) are mainly from multiple atmospheric secondaries produced by the same primary cosmic ray. We calculate the fraction of unrelated counts, the ‘leader fraction,’ for the large-separation case and correct for the atmospheric and water vapor pressure to observe its time variation between Sep 2018 to Dec 2019. This is a novel technique to study cosmic-ray spectral properties and multiplicities of secondary particles in the air showers using a single neutron monitor station. This research project is partially supported by Thailand Science Research and Innovation grant RTA6280002 and Research Grant for New Scholar MRG6280155.
Recent upgrade of the neutron monitor at Mawson, Antarctica
Alejandro Sáiz*,1, Pradiphat Muangha 1, Marc Duldig 2, David Ruffolo 1,3, Warit Mitthumsiri 1, Kullapha Chaiwongkhot 1, Waraporn Nuntiyakul 4,3, Paul Evenson 5, John Humble 2
1 Department of Physics, Faculty of Science, Mahidol University, Bangkok 10400, Thailand
2 School of Natural Sciences, University of Tasmania, Hobart, Tasmania 7001, Australia
3 National Astronomical Research Institute of Thailand (NARIT), Chiang Mai 50180, Thailand
4 Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand
5 Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, DE 19716, USA
* Presenting author (alejandro.sai@mahidol.ac.th)
During the Austral Summer of 2019/2020, two scientists from Mahidol University, Thailand, joined the expedition to the Australian base of Mawson, Antarctica, to perform several upgrades to the neutron monitor at the Mawson Cosmic Ray Laboratory. Changes in the data acquisition system included both updated electronic firmware and computer software. The most relevant addition to the data stream is the measurement of waiting times between pulses, which can be used to detect cosmic ray spectral changes. Besides the same-counter waiting times, values for cross-counter waiting times are also recorded, which may be used to study the structure of atmospheric showers. The detector was also extended to include 6 extra BP28 counters as a lead-free counter array, which will also give valuable spectral information, especially during GLEs. In this presentation, details of this upgrade will be given and an initial analysis of the new data products will be presented. Partially supported by Thailand Science Research and Innovation award RTA6280002 and Research Grant for New Scholar MRG6280155.
Refurbishment of the SANAE neutron monitor
Du Toit Strauss, Center for Space Research, North-West University, South Africa.
Corrie Diedericks, Center for Space Research, North-West University, South Africa.
Cobus van der Merwe, Center for Space Research, North-West University, South Africa.
Hendrik Kruger, Center for Space Research, North-West University, South Africa.
Katlego Moloto, Center for Space Research, North-West University, South Africa.
Helena Kruger, Center for Space Research, North-West University, South Africa.
We present results of the recent upgrade of the SANAE (South African National Antarctic Expedition) neutron monitor (NM). We have retro-fitted a 3NM64 with electronics, originally designed for our mini-NM program, which have the ability to record individual cosmic ray pulses down to the low micro-second level. We briefly discuss the retro-fitting process and present initial results for the first year of operation, including, amongst others, measurements of the multiplicity spectrum and the level of tube degradation. We also discuss the data analysis we implemented to combine the counts from each tube into a near-real-time time series.
A new neutron monitor at Livingston Island (Antarctic Peninsula)
J.J. Blanco, O. García-Población, J.I. García-Tejedor, S.Ayuso, A. López-Comazzi, I. Vrublevskyy, Alcala University, Alcalá de Henares, Spain
and
C. T. Steigies Christian Steigies, Christian-Albrechts-Universität zu Kiel, Germany
A new neutron monitor (NEMO) was installed at the Spanish Antarctic base Juan Carlos I on Livingston Island in January 2019 as part of the Antarctic Cosmic Ray Observatory (ORCA). After three months of operation the monitor stopped working when the available power supplied by batteries and solar panels ran out. NEMO was turned on again in January 2020 and was integrated into the renewable energy grid of the base allowing NEMO to operate continuously until the present moment. NEMO consists of a set of 3NM64 (NEMO-3NM63) and 3 bare counters (NEMO-3BNM) filled with BF3 stacked with a muon telescope (MITO) sharing a common housing. The first year of data is presented.
Novel registration system for Neutron Monitors
Stephan I. Böttcher, Universität Kiel, Germany
Christian T. Steigies, Universität Kiel, Germany
Rolf Bütikofer, University of Bern, Switzerland
We present a novel registration system for counter signals based on an FPGA and a µC with USB, serial Port, and Ethernet interfaces. An interface board for up to 24 counter channels can be configured for a wide range of signal levels. Each channel comes with a programmable discriminator. The FPGA reports the observed pulse length, for frontends that encode pulse height information.
Data management of the Oulu cosmic ray station
Stepan Poluianov (Sodankylä Geophysical Observatory, University of Oulu, Finland; Space Physics and Astronomy Research Unit, University of Oulu, Finland), Ilya Usoskin (1.Sodankylä Geophysical Observatory, University of Oulu, Finland; 2.Space Physics and Astronomy Research Unit, University of Oulu, Finland), Askar Ibragimov (independent researcher, Helsinki, Finland)
With the recent electronics upgrade of Antarctic neutron monitors DOMC and DOMB in 2019, the Oulu cosmic ray station (Sodankylä Geophysical Observatory, Finland) receives a significantly larger amount of data than before. This has led to a need for an important upgrade of the configuration of servers working at the station. The new configuration has three types of servers: a webserver, a datamaster and data acquisition machines. The webserver provides a user interface for services of the station: the main website, the GLE database and other services. The datamaster is the main server, which stores all data in raw files and in a database. Data acquisition machines are computers, directly receiving data from the instruments that are sent further to the datamaster. This work describes technical details of the cosmic ray station setup providing reliable and secure data acquisition, handling and publication.
Reformatting of neutron monitor to increase its effectivity
Yanke V.G. Pushkov Institute of terrestrial magnetism, ionosphere and radio wave propagation (IZMIRAN), Moscow, Russia
Global changes of climate, including the gradually decreasing thickness of ice, lead to objective difficulties for organizing annual Arctic North Pole expeditions on drifting ice. To solve this problem, an all-weather Arctic-class self-propelled research platform for year-round expeditions is currently under construction. On such an icebreaker on the upper deck in a sea container, one section of the 6nm64 neutron supermonitor will be placed. But for solar cosmic rays, first of all, it is desirable to have good statistical accuracy of the data. To place a larger number of sections does not allow the weight inherent in the project. Therefore, the task of the work is to increase its efficiency by reformatting a neutron detector. The key points of this reformatting are the transition to helium counters, the rejection of lead ring-shaped multiplier and the transition to brick. This allows us to increase the number of used counters and neutron collection. The latter, however, increases the cost of the detector, but leads to an increase in its efficiency by 1.5 - 2.5 times, depending on the helium counters used.
In addition, the asymptotic directions of particle arrival in the geomagnetic field are calculated for possible drift points of the North Pole station, on the one hand, and the expected trajectory of the Earth's North magnetic pole, on the other hand. During the movement of the North Pole floating platform when registering a specific event, we may be at the best point, we may be at the worst point, but in any case it will be a unique region for conducting cosmophysical research.
Installation of Jang Bogo neutron monitor in Antarctica
Jongil Jung, Department of Astronomy, Space Science and Geology, Chungnam National University, Daejeon, Korea; Korea Polar Research Institute, Incheon, Korea
Suyeon Oh, Department of Earth Science Education, Chonnam National University, Gwangju, Korea
Yu Yi, Department of Astronomy, Space Science and Geology, Chungnam National University, Daejeon, Korea
Paul Evenson, Department of Physics and Astronomy, University of Delaware, Newark, United States
Gunhwa Gee, Korea Polar Research Institute, Incheon, Korea
JeongHan Kim, Korea Polar Research Institute, Incheon, Korea
Changsup Lee, Korea Polar Research Institute, Incheon, Korea
The Jang Bogo research base is secondary base of South Korea and built in February 2014 and located in Terra Nova Bay, Northern Victoria Land, Antarctica. It is a state-of-the-art research station that provides easy access to central and coastal areas of Antarctica. It is also possible to produce various data and study specialized research such as climate change, topographical and geological, the upper atmosphere and space science. We have been operating the neutron monitor at Jang Bogo base since December 2015. Its location is 76.62S, 164.2E in geophysical coordinate and 79.86N, 52.46W in geomagnetic coordinate. Jang Bogo neutron monitor (JBGO) has the cutoff rigidity of about 0.1 GV. It consists of 18 tubes of three-units which were transferred from McMurdo station (MCMU) at a distance of 300km from Jang Bogo. One of three units was relocated in 2015 and the rest of units was transferred in the summer season of 2017-2019. Currently, JBGO is running well without a big problem. We respect that JBGO gives the good information to understand the space environment in the polar region. In this study, we present the installation of JBGO and preliminary scientific results using the JBGO data.
Upgrade of electronics of neutron monitors DOMC and DOMB
Stepan Poluianov (Sodankylä Geophysical Observatory, University of Oulu, Finland; Space Physics and Astronomy Research Unit, University of Oulu, Finland)
Ilya Usoskin (1.Sodankylä Geophysical Observatory, University of Oulu, Finland; 2. Space Physics and Astronomy Research Unit, University of Oulu, Finland)
Du Toit Strauss (Centre for Space Research, North-West University, Potchefstroom, South Africa)
DOMC and DOMB neutron monitors operate at the Concordia research station (Dome C on the Antarctic plateau, 75º06’S, 123º23’E, 3233 m a.s.l.) since 2015. Their high elevation and proximity to the geomagnetic pole provide low atmospheric and geomagnetic cutoffs and, therefore, the exceptionally high sensitivity of measurements. The instruments are the so-called mini neutron monitors with BF3-filled counter tubes. DOMC has the standard design with a lead neutron multiplier and DOMB is a so-called “bare” (lead-free) unit.
We report on a recent upgrade of electronics heads of instruments. New heads have modular architecture built upon a single-board computer Raspberry Pi. The upgrade increases capabilities of the instruments in two directions: (1) measurements, particularly, of cosmic ray multiplicity; (2) remote control and monitoring. The new electronic heads register each pulse from a detector giving a timestamp with microsecond precision, which is crucial for multiplicity measurements. Many important parameters (e.g., high voltage, pulse detection thresholds) can be controlled and adjusted remotely with the new design. High computing power allows performing data processing on the fly. The upgrade increases the capability of DOMC and DOMB in cosmic ray measurements and improves control of the operation of the neutron monitors.