Abstract
Mini-EUSO is a telescope observing the Earth in the ultraviolet band from the International Space Station. It is a part of the JEM-EUSO program, paving the way to future larger missions, ...such as K-EUSO and POEMMA, devoted primarily to the observation of ultrahigh-energy cosmic rays from space. Mini-EUSO is capable of observing extensive air showers generated by ultrahigh-energy cosmic rays with an energy above 10
21
eV and to detect artificial showers generated with lasers from the ground. Other main scientific objectives of the mission are the search for nuclearites and strange quark matter, the study of atmospheric phenomena such as transient luminous events, meteors, and meteoroids, the observation of sea bioluminescence and of artificial satellites and man-made space debris. Mini-EUSO will map the nighttime Earth in the UV range (290–430 nm), with a spatial resolution of about 6.3 km and a temporal resolution of 2.5
μ
s, through a nadir-facing UV-transparent window in the Russian Zvezda module. The instrument, launched on 2019 August 22, from the Baikonur Cosmodrome, is based on an optical system employing two Fresnel lenses and a focal surface composed of 36 multianode photomultiplier tubes, 64 channels each, for a total of 2304 channels with single-photon counting sensitivity and an overall field of view of 44°. Mini-EUSO also contains two ancillary cameras to complement measurements in the near-infrared and visible ranges. In this paper, we describe the detector and present the various phenomena observed in the first months of operations.
Context . Observations of meteors in the Earth’s atmosphere offer a unique tool for determining the flux of meteoroids that are too small to be detected by direct telescopic observations. Although ...these objects are routinely observed from ground-based facilities, such as meteor and fireball networks, space-based instruments come with notable advantages and have the potential to achieve a broad and uniform exposure. Aims . In this paper, we describe the first observations of meteor events with Mini-EUSO, a very wide field-of-view telescope launched in August 2019 from the Baikonur cosmodrome and installed on board the Russian Zvezda module of the International Space Station. Mini-EUSO can map the night-time Earth in the near-UV range (290-130 nm) with a field of view equal to 44° × 44° and a spatial resolution of about 4.7 km at an altitude of 100 km from the ground. The detector saves triggered transient phenomena with a sampling frequency of 2.5 µs and 320 µs, as well as a continuous acquisition at 40.96 ms scale that is suitable for meteor observations. Methods . We designed two dedicated and complementary trigger methods, together with an analysis pipeline able to estimate the main physical parameters of the observed population of meteors, such as the duration, horizontal speed, azimuth, and absolute magnitude. To compute the absolute flux of meteors from Mini-EUSO observations, we implemented a simulation framework able to estimate the detection efficiency as a function of the meteor magnitude and the background illumination conditions. Results . The instrument detected 24 thousand meteors within the first 40 data-taking sessions from November 2019 to August 2021, for a total observation time of approximately 6 days with a limiting absolute magnitude of +6. Our estimation of the absolute flux density of meteoroids in the range of mass between 10 −5 kg to 10 −1 kg was found to be comparable to other results available in the literature. Conclusions . The results of this work prove the potential for space-based observations to increase the statistics of meteor observations achievable with instruments operating on the ground. The slope of the mass distribution of meteoroids sampled with Mini-EUSO suggests a mass index of either s = 2.09 ± 0.02 or s = 2.31 ± 0.03, according to two different methodologies for the computation of the pre-atmospheric mass starting from the luminosity of each event.
EUSO-TA is a ground-based fluorescence telescope built to validate the design of ultra-high energy cosmic ray fluorescence detectors to be operated in space with the technology developed within the ...Joint Exploratory Missions for Extreme Universe Space Observatory (JEM-EUSO) program. It operates at the Telescope Array (TA) site in Utah, USA. With an external trigger provided by the Black Rock Mesa fluorescence detectors of the Telescope Array experiment, with EUSO-TA we observed air-showers from ultra-high energy cosmic rays, as well as laser events from the Central Laser Facility at the TA site and from portable lasers like the JEM-EUSO Global Light System prototype. Since the Black Rock Mesa fluorescence detectors have a ∼30 times larger field of view than EUSO-TA, they allow a primary energy reconstruction based on the observation of a large part of the shower evolution, including the shower maximum, while EUSO-TA observes only a part of it, usually far away from the maximum. To estimate the detection limits of EUSO-TA in energy and distance, a method was developed to re-scale their energy, taking into account that EUSO-TA observes only a portion of the air-showers. The method was applied on simulation sets with showers with different primaries, energy, direction, and impact point on the ground, as well as taking into account the experimental environment. EUSO-TA was simulated with an internal trigger and different elevation angles and electronics. The same method was then applied also to real measurements and compared to the simulations. In addition, the method can also be used to estimate the detection limits for experiments that are operated at high altitudes and in most cases can see the maximum of the showers. This was done for EUSO-SPB1, an instrument installed on a super-pressure balloon. Finally, the expected detection rates for EUSO-TA were also assessed using the prepared simulated event sets. The rates correspond to a few detections per recording session of 30 h of observation, depending on the background level and the configuration of the detector.
The BSUIN project - overview and same results Dȩbicki, Z; Jȩdrzejczak, K; Kasztelan, M ...
Journal of physics. Conference series,
02/2019, Letnik:
1181, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The Baltic Sea Underground Innovation Network (BSUIN) 1 project aims to make the underground laboratories in the Baltic Sea region more accessible for innovation, business development and science by ...improving the information about the underground laboratories, the operation, user experiences and safety. BSUIN is EU funded by Interreg Baltic Sea 2 funding cooperation. The BSUIN consortium has 14 members from eight Baltic Sea countries. Six underground labs are looking for new collaboration in the project. One of the goals of the BSUIN project is to propose standard methods for the characterization of underground laboratories, including natural radiation background characterisation. We have proposed scheme for thermal neutron flux measurement: simple and low-cost but still very reliable. A pilot measurements were made in mines in Freiberg (Germany) Data analysis is in progress
Within the Baltic Sea Underground Innovation Network (BSUIN) project, we design and build a multichannel signal analysis and acquisition system. Our device can acquire signals from up to 32 detectors ...at the same time. Each channel has symmetric input, independent adjustable analog trigger, 10 MHz sampling rate, and 10 bits ADC resolution. Micro-controller (μC), FPGA, and micro-processor with Linux allow for different configuration of the system and for preliminary data analysis. In principle the signal's wave-forms from each channel are stored in memory, and a pulse shape analysis can be performed. Independent power suppliers are provided for each channel. We are going to use this measuring system for neutron registration with large number of neutron detectors (helium proportional counters, scintillation neutron detectors, and charged particle scintillation detectors). Especially, measurements of simultaneous measurement of coherent signals from a number of neutron detectors is the purpose for this data acquisition system.
The Mini-EUSO telescope was launched for the International Space Station on August 22nd, 2019 to observe from the ISS orbit (∼400 km altitude) various phenomena occurring in the Earth’s atmosphere ...through a UV-transparent window located in the Russian Zvezda Module. Mini-EUSO is based on a set of two Fresnel lenses of 25 cm diameter each and a focal plane of 48×48 pixels, for a total field of view of 44°. Until July 2021, Mini-EUSO performed a total of 41 data acquisition sessions, obtaining UV images of the Earth in the 290 nm – 430 nm band with temporal and spatial resolution on ground of 2.5 μs and 6.3×6.3 km2, respectively. The data acquisition was performed with a 2.5 μs sampling rate, using a dedicated trigger looking for signals with a typical duration of tens of μs.
In the present paper the analysis of the performance of the 2.5 μs trigger logic is presented, with a focus on the method used for the analysis and the categories of triggered events. The expected functioning of the trigger logic has been confirmed, with the trigger rate on spurious events that remains within the requirements in nominal background conditions. The trigger logic detected several different phenomena, including lightning strikes, elves, ground-based flashers and events with EAS-like characteristics.
The Trigger Logic (TL) of the Tracking Ultraviolet Setup (TUS) and Multiwavelength Imaging New Instrument for the Extreme Universe Space Observatory (Mini-EUSO) space-based projects of the Joint ...Experiment Missions-EUSO (JEM-EUSO) program is summarized. The performance results on the search for Ultra-High Energy Cosmic Rays (UHECRs) are presented.
Abstract
The complexity of modern cosmic ray observatories and the
rich data sets they capture often require a sophisticated software
framework to support the simulation of physical processes, ...detector
response, as well as reconstruction and analysis of real and
simulated data. Here we present the EUSO-Offline framework. The
code base was originally developed by the Pierre Auger
Collaboration, and portions of it have been adopted by other
collaborations to suit their needs. We have extended this software
to fulfill the requirements of Ultra-High Energy Cosmic Ray
detectors and very high energy neutrino detectors developed for the
Joint Exploratory Missions for an Extreme Universe Observatory
(JEM-EUSO). These path-finder instruments constitute a program to
chart the path to a future space-based mission like POEMMA. For
completeness, we describe the overall structure of the framework
developed by the Auger collaboration and continue with a description
of the JEM-EUSO simulation and reconstruction capabilities. The
framework is written predominantly in modern C++ (compliled against
C++17) and incorporates third-party libraries chosen based on
functionality and our best judgment regarding support and
longevity. Modularity is a central notion in the framework design, a
requirement for large collaborations in which many individuals
contribute to a common code base and often want to compare different
approaches to a given problem. For the same reason, the framework is
designed to be highly configurable, which allows us to contend with
a variety of JEM-EUSO missions and observation scenarios. We also
discuss how we incorporate broad, industry-standard testing coverage
which is necessary to ensure quality and maintainability of a
relatively large code base, and the tools we employ to support a
multitude of computing platforms and enable fast, reliable
installation of external packages. Finally, we provide a few
examples of simulation and reconstruction applications using
EUSO-Offline.
Mini-EUSO is a high-sensitivity imaging telescope that observes the Earth from the ISS in the near ultraviolet band (290
÷
430 nm), through the nadir-facing, UV-transparent window in the Russian ...Zvezda module. The instrument, launched in 2019, has a field of view of 44
∘
, a spatial resolution on the Earth’s surface of 6.3 km and a temporal sampling rate of 2.5 microseconds. Thanks to its triggering and on-board processing, the telescope is capable of detecting UV emissions of cosmic, atmospheric, and terrestrial origin on different time scales, from a few microseconds up to tens of milliseconds. The optics is composed of two Fresnel lenses focusing light onto an array of 36 Hamamatsu Multi-Anode PhotoMultiplier Tubes, for a total of 2304 pixels. The telescope also contains two cameras in the near-infrared and visible, an 8-by-8 array of Silicon-PhotoMultipliers and a series of UV sensors to manage night-day transitions. The scientific objectives range from the observation of atmospheric phenomena lightning, Transient Luminous Events (TLEs), ELVES, the study of meteoroids, the search of interstellar meteoroids and strange quark matter, mapping of the Earth’s nocturnal emissions in the ultraviolet range, and the search of cosmic rays with energy above 10
21
eV. The instrument has been integrated and qualified in 2019, with the final tests in Baikonur prior to its launch. Operations involve periodic installation in the Zvezda module of the station with observations during the crew night time, with periodic downlink of data samples, with the full data being sent to the ground via pouches containing the data disks. Mission planning involves the selection of the optimal orbits to maximize the scientific return of the instrument. In this work, we will describe the various phases of construction, testing, and qualification prior to the launch and the in-flight operations of the instrument on board the ISS.
The
Extreme Universe Space Observatory on a Super Pressure Balloon 1
(EUSO-SPB1) instrument was launched out of Wanaka, New Zealand, by NASA in April, 2017 as a mission of opportunity. The detector ...was developed as part of the
Joint Experimental Missions for the Extreme Universe Space Observatory
(JEM-EUSO) program toward a space-based ultra-high energy cosmic ray (UHECR) telescope with the main objective to make the first observation of UHECRs via the fluorescence technique from suborbital space. The EUSO-SPB1 instrument is a refractive telescope consisting of two 1m
2
Fresnel lenses with a high-speed UV camera at the focal plane. The camera has 2304 individual pixels capable of single photoelectron counting with a time resolution of 2.5
μ
s. A detailed performance study including calibration was done on ground. We separately evaluated the properties of the Photo Detector Module (PDM) and the optical system in the laboratory. An end-to-end test of the instrument was performed during a field campaign in the West Desert in Utah, USA at the Telescope Array (TA) site in September 2016. The campaign lasted for 8 nights. In this article we present the results of the preflight laboratory and field tests. Based on the tests performed in the field, it was determined that EUSO-SPB1 has a field of view of 11.1
∘
and an absolute photo-detection efficiency of 10%. We also measured the light flux necessary to obtain a 50% trigger efficiency using laser beams. These measurements were crucial for us to perform an accurate post flight event rate calculation to validate our cosmic ray search. Laser beams were also used to estimated the reconstruction angular resolution. Finally, we performed a flat field measurement in flight configuration at the launch site prior to the launch providing a uniformity of the focal surface better than 6%.
PDF
