The Fluorescence Telescope is one of the two telescopes on board the Extreme Universe Space Observatory on a Super Pressure Balloon II (EUSO-SPB2). EUSO-SPB2 is an ultra-long-duration balloon mission that aims at the detection of Ultra High Energy Cosmic Rays (UHECR) via the fluorescence technique (using a Fluorescence Telescope) and of Ultra High Energy (UHE) neutrinos via Cherenkov emission (using a Cherenkov Telescope). The mission is planned to fly in 2023 and is a precursor of the Probe of Extreme Multi-Messenger Astrophysics (POEMMA). The Fluorescence Telescope is a second generation instrument preceded by the telescopes flown on the EUSO-Balloon and EUSO-SPB1 missions. It features Schmidt optics and has a 1-meter diameter aperture. The focal surface of the telescope is equipped with a 6912-pixel Multi Anode Photo Multipliers (MAPMT) camera covering a 37.4 x 11.4 degree Field of Regard. Such a big Field of Regard, together with a flight target duration of up to 100 days, would allow, for the first time from suborbital altitudes, detection of UHECR fluorescence tracks. This contribution will provide an overview of the instrument including the current status of the telescope development.
POEMMA-Balloon with Radio (PBR) is designed as a payload for a NASA suborbital Super Pressure Balloon that will circle over the Southern Ocean and a mission duration as long as 50 days. The PBR instrument consists of a 1.1 m aperture Schmidt telescope similar to the POEMMA design with two cameras in its focal surface: a Fluorescence Camera (FC) and a Cherenkov Camera (CC). The CC camera is mainly devoted to the observation of cosmic-ray-induced high-altitude horizontal air showers (HAHAs) and search for neutrino-induced upward-going EAS. It will be made of 2048 SiPMs with a surface of 3 × 3 mm2 and a FoV of 12° by 6°, covering a spectral range of 320–900 nm. The CC camera is an innovative detector currently under construction. In this paper, information about its current status will be given.
The space-borne PAMELA experiment was launched on the 15th of June 2006 on board the Russian satellite Resurs-DK1 from the Baikonur Cosmodrome. The PAMELA instrument performed high-precision measurements of cosmic rays over a wide energy range until January 2016. We present the yearly average deuteron spectra for the 23rd solar minimum (July 2006 - January 2009) and the first part of the 24th solar maximum (until September 2014). The deuterons were selected with a rigidity between 0.75 and 2.6 GV by combining the Time of Flight (ToF) and the tracker systems. The measured spectra display a rising trend toward the solar minimum followed by a decreasing trend as the solar maximum approaches. The corresponding deuteron-to-proton flux ratios show time dependence at the lowest rigidities, as expected due to the different charge-to-mass ratios and the different shapes of the respective local interstellar spectra. These results are significant for the fine-tuning of propagation and modulation models of cosmic rays through the heliosphere.
The POEMMA-Balloon with Radio (PBR) mission incorporates an advanced data processing system (DP) to enable the detection and characterization of ultra-high-energy cosmic rays and astrophysical neutrinos. The data acquisition (DAQ) system integrates inputs from the Cherenkov Camera, the Fluorescence Camera, the Radio Instrument and the X-Gamma detectors, ensuring synchronized event detection. Built upon the heritage of the EUSO-SPB2 DAQ architecture, the system has been adapted to support both the hybrid focal surface and radio instrumentation. The DP features two redundant CPUs, differential GPS receivers, and environmental monitoring capabilities, including temperature, humidity, and gyroscope-based orientation tracking. A central clock board synchronizes data collection across all instruments, ensuring precise event reconstruction. The main trigger and clock board manages trigger signals from different detectors, supporting both joint and independent data acquisition modes. These advancements enhance the mission's contribution to multi-messenger astrophysics and provide valuable insights for future space-based observatories. In this paper, we describe the system's main components and the design developed for this new mission.
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-(Off) over bar(line) under bar 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-(Off) over bar(line) under bar.
The Extreme Universe Space Observatory on a Super Pressure Balloon 1 (EUSO-SPB1) was launched in 2017 April from Wanaka, New Zealand. The plan of this mission of opportunity on a NASA super pressure balloon test flight was to circle the southern hemisphere. The primary scientific goal was to make the first observations of ultra-high-energy cosmic-ray extensive air showers (EASs) by looking down on the atmosphere with an ultraviolet (UV) fluorescence telescope from suborbital altitude (33~km). After 12~days and 4~hours aloft, the flight was terminated prematurely in the Pacific Ocean. Before the flight, the instrument was tested extensively in the West Desert of Utah, USA, with UV point sources and lasers. The test results indicated that the instrument had sensitivity to EASs of approximately 3 EeV. Simulations of the telescope system, telescope on time, and realized flight trajectory predicted an observation of about 1 event assuming clear sky conditions. The effects of high clouds were estimated to reduce this value by approximately a factor of 2. A manual search and a machine-learning-based search did not find any EAS signals in these data. Here we review the EUSO-SPB1 instrument and flight and the EAS search.
This is a collection of papers presented by the JEM-EUSO Collaboration at the 38th International Cosmic Ray Conference (Nagoya, Japan, July 26-August 3, 2023)
EUSO-SPB2 (Extreme Universe Space Observatory on a Super Pressure Balloon II) is a precursor mission for a future space observatory for multi-messenger astrophysics, planned to be launched in Spring 2023 with a flight duration target of 100 days. The Fluorescence Telescope (FT) hosted on board is designed to detect Ultra High Energy Cosmic Rays via the UV fluorescence emission of the Extensive Air Showers in the atmosphere. The Data Processor (DP) of the FT is the component of the electronics system that performs data management and instrument control for the telescope. The DP controls front-end electronics, tags events with arrival time and payload position through a GPS system, provides signals for time synchronization of the event and measures the live and dead time of the telescope. Furthermore, it manages mass memory for data storage, performs housekeeping monitoring, and controls the power-on and power-off sequences. Finally, the data processor combines the data from the PDMs and onboard differential GPS and prioritizes data for download. The long duration of the flight poses strict requirements on electronics and data handling. The operations at high altitude in an unpressurized environment represent a technological challenge for heat dissipation. This contribution will provide an overview of the innovative elements developed and the results of the integration and field test campaigns. We will also present some preliminary analysis of the performance during the flight.
EUSO-SPB2 (Extreme Universe Space Observatory on a Super Pressure Balloon II) is a precursor mission for a future space observatory for multi-messenger astrophysics, planned to be launched in Spring 2023 with a flight duration target of 100 days. The Fluorescence Telescope (FT) hosted on board is designed to detect Ultra High Energy Cosmic Rays via the UV fluorescence emission of the Extensive Air Showers in the atmosphere. The Data Processor (DP) of the FT is the component of the electronics system that performs data management and instrument control for the telescope. The DP controls front-end electronics, tags events with arrival time and payload position through a GPS system, provides signals for time synchronization of the event and measures the live and dead time of the telescope. Furthermore, it manages mass memory for data storage, performs housekeeping monitoring, and controls the power-on and power-off sequences. Finally, the data processor combines the data from the PDMs and onboard differential GPS and prioritizes data for download. The long duration of the flight poses strict requirements on electronics and data handling. The operations at high altitude in an unpressurized environment represent a technological challenge for heat dissipation. This contribution will provide an overview of the innovative elements developed and the results of the integration and field test campaigns. We will also present some preliminary analysis of the performance during the flight.
A Forbush decrease (FD) is a sudden drop of cosmic-ray intensity arising as an effect of coronal mass ejection (CME) propagation in interplanetary space. The different physical properties of each CME cause variability in the FDs observed by scientific instruments. A comprehensive study of both phenomena is required to properly understand the processes involved in FDs. Most of the current studies in this field use experimental data obtained by ground-based apparatus that measure the flux of cosmic rays via their interaction with Earth’s atmosphere. Direct measurements in space of FDs are rather rare. In this work, we present the results obtained by the spacecraft-borne experiment Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics (PAMELA). The experiment took data from 15 June 2006 until January 2016. A series of FDs during the period 2006 – 2013 were studied. Only significant events with amplitude ≥ 10 R = 1.1 – 2.9 GV were taken into account. The dependencies of the recovery times on the particle rigidity were obtained for FD events generated by halo-type CMEs.
JEM-EUSO is an international program for the development of space-based Ultra-High Energy Cosmic Ray observatories. The program consists of a series of missions which are either under development or in the data analysis phase. All instruments are based on a wide-field-of-view telescope, which operates in the near-UV range, designed to detect the fluorescence light emitted by extensive air showers in the atmosphere. We describe the simulation software ESAF in the framework of the JEM-EUSO program and explain the physical assumptions used. We present here the implementation of the JEM-EUSO, POEMMA, K-EUSO, TUS, Mini-EUSO, EUSO-SPB1 and EUSO-TA configurations in ESAF. For the first time ESAF simulation outputs are compared with experimental data.
The isotopic composition of Li and Be nuclei in the 1–5 GV range of rigidities (nuclear energies of 0.1–1.5 GeV/nucleon) is analyzed using PAMELA flight data from 2006–2014 on the rigidity of detected nuclei and their velocities (time-of-flight analysis and ionization losses in the detector’s multilayer calorimeter). The new PAMELA data expand the range of energies in earlier measurements, are consistent with scarce results, and indicate correlated deviations of Li and Be isotope ratios from the GALPROP data for GCRs, which can be interpreted as evidence of contributions from several nearby local sources against the GCR background. Analysis of precision AMS-02 data on the spectra of positrons, antiprotons, and secondary nuclei of Li, Be, and B also indicates correlated increases in intensity at rigidities of ~50–1000 GV, which could also be due to local sources. The contribution from local sources against the GCR background is estimated at levels of tens of percents for rigidities of 1–5 GV and several percent at rigidities of 50–1000 GV.
Abstract The TOTEM collaboration at the CERN LHC has measured the differential cross-section of elastic proton–proton scattering at $$\sqrt{s} = 8\,\mathrm{TeV}$$ s = 8 TeV in the squared four-momentum transfer range $$0.2\,\mathrm{GeV^{2}}< |t| < 1.9\,\mathrm{GeV^{2}}$$ 0.2 GeV 2 < | t | < 1.9 GeV 2 . This interval includes the structure with a diffractive minimum (“dip”) and a secondary maximum (“bump”) that has also been observed at all other LHC energies, where measurements were made. A detailed characterisation of this structure for $$\sqrt{s} = 8\,\mathrm{TeV}$$ s = 8 TeV yields the positions, $$|t|_{\mathrm{dip}} = (0.521 \pm 0.007)\,\mathrm{GeV^2}$$ | t | dip = ( 0.521 ± 0.007 ) GeV 2 and $$|t|_{\mathrm{bump}} = (0.695 \pm 0.026)\,\mathrm{GeV^2}$$ | t | bump = ( 0.695 ± 0.026 ) GeV 2 , as well as the cross-section values, $$\left. {\mathrm{d}\sigma /\mathrm{d}t}\right| _{\mathrm{dip}} = (15.1 \pm 2.5)\,\mathrm{{\mu b/GeV^2}}$$ d σ / d t dip = ( 15.1 ± 2.5 ) μ b / GeV 2 and $$\left. {\mathrm{d}\sigma /\mathrm{d}t}\right| _{\mathrm{bump}} = (29.7 \pm 1.8)\,\mathrm{{\mu b/GeV^2}}$$ d σ / d t bump = ( 29.7 ± 1.8 ) μ b / GeV 2 , for the dip and the bump, respectively.
Mini-EUSO is a small orbital telescope with a field of view of $44^{\circ}\times 44^{\circ}$, observing the night-time Earth mostly in 320-420 nm band. Its time resolution spanning from microseconds (triggered) to milliseconds (untriggered) and more than $300\times 300$ km of the ground covered, already allowed it to register thousands of meteors. Such detections make the telescope a suitable tool in the search for hypothetical heavy compact objects, which would leave trails of light in the atmosphere due to their high density and speed. The most prominent example are the nuclearites -- hypothetical lumps of strange quark matter that could be stabler and denser than the nuclear matter. In this paper, we show potential limits on the flux of nuclearites after collecting 42 hours of observations data.
EUSO-Balloon is a pathfinder for JEM-EUSO, the mission concept of a spaceborne observatory which is designed to observe Ultra-High Energy Cosmic Ray (UHECR)-induced Extensive Air Showers (EAS) by detecting their UltraViolet (UV) light tracks “from above.” On August 25, 2014, EUSO-Balloon was launched from Timmins Stratospheric Balloon Base (Ontario, Canada) by the balloon division of the French Space Agency CNES. After reaching a floating altitude of 38 km, EUSO-Balloon imaged the UV light in the wavelength range ∼290–500 nm for more than 5 hours using the key technologies of JEM-EUSO. The flight allowed a good understanding of the performance of the detector to be developed, giving insights into possible improvements to be applied to future missions. A detailed measurement of the photoelectron counts in different atmospheric and ground conditions was achieved. By means of the simulation of the instrument response and by assuming atmospheric models, the absolute intensity of diffuse light was estimated. The instrument detected hundreds of laser tracks with similar characteristics to EASs shot by a helicopter flying underneath. These are the first recorded laser tracks measured from a fluorescence detector looking down on the atmosphere. The reconstruction of the direction of the laser tracks was performed. In this work, a review of the main results obtained by EUSO-Balloon is presented as well as implications for future space-based observations of UHECRs.
Mini-EUSO is a telescope launched on board the International Space Station in 2019 and currently located in the Russian section of the station. 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. It is also capable of observing Extensive Air Showers generated by Ultra-High Energy Cosmic Rays with an energy above 10$^{21}$ eV and detect artificial showers generated with lasers from the ground. Mini-EUSO can map the night-time Earth in the UV range (290 - 430 nm), with a spatial resolution of about 6.3 km and a temporal resolution of 2.5 $\mu$s, observing our planet through a nadir-facing UV-transparent window in the Russian Zvezda module. The instrument, launched on 2019/08/22 from the Baikonur cosmodrome is based on an optical system employing two Fresnel lenses and a focal surface composed of 36 Multi-Anode Photomultiplier tubes, 64 channels each, for a total of 2304 channels with single photon counting sensitivity and an overall field of view of 44$^{\circ}$. 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 year of operation.
Time-dependent energy spectra of galactic cosmic rays (GCRs) carry fundamental information regarding their origin and propagation. When observed at the Earth, these spectra are significantly affected by the solar wind and the embedded solar magnetic field that permeates the heliosphere, changing significantly over an 11 yr solar cycle. Energy spectra of GCRs measured during different epochs of solar activity provide crucial information for a thorough understanding of solar and heliospheric phenomena. The PAMELA experiment collected data for almost 10 years (2006 June 15–2016 January 23), including the minimum phase of solar cycle 23 and the maximum phase of solar cycle 24. In this paper, we present new spectra for helium nuclei measured by the PAMELA instrument from 2010 January to 2014 September over a three-Carrington-rotation time basis. These data are compared to the PAMELA spectra measured during the previous solar minimum, providing a picture of the time dependence of the helium-nuclei fluxes over a nearly full solar cycle. Time and rigidity dependencies are observed in the proton-to-helium flux ratios. The force-field approximation of the solar modulation was used to relate these dependencies to the shapes of the local interstellar proton and helium-nuclei spectra.
Compilation of papers presented by the JEM-EUSO Collaboration at the 37th International Cosmic Ray Conference (ICRC), held on July 12-23, 2021 (online) in Berlin, Germany.
Hyper-Kamiokande (HK) is the next generation underground water Cherenkov detector that builds on the highly successful Super-Kamiokande (SK) experiment. The 260,000-ton detector has an 8.4 times larger fiducial volume than its predecessor. HK's low energy threshold combined with the very large fiducial volume make the detector unique; HK is expected to acquire an unprecedented exposure of 3.8 Mton-year over a period of 20 years starting in 2027. It has an extremely diverse science program including long-baseline neutrino oscillation measurements, nucleon decay searches, atmospheric neutrinos, neutrinos from the sun and supernova explosions, and neutrinos from other astrophysical origins. Like DUNE, the flagship project of the U.S. high-energy physics program, HK measures fundamental properties of neutrinos such as the search for leptonic CP violation and neutrino physics beyond the Standard Model.
The TOTEM (TOTal cross section, Elastic scattering and diffraction dissociation Measurement at the LHC) experiment, located at the interaction point 5 of the LHC, has measured the total, elastic and inelastic proton-proton crosssections, using a luminosity independent method, based on the optical theorem, in a center-of-mass energy range from 2.76 to 13 TeV. The elastic scattering was investigated in a wide range of the squared four-momentum transfer |t| allowing study of the Coulomb-nuclear interference region down to |t| ∼ 8 × 10−4 GeV2. This made possible the first measurement of the ρ parameter at √s = 13 TeV, ρ being the ratio between the real and the imaginary part of the nuclear elastic scattering amplitude at t = 0. This measurement, combined with the total crosssection results, led to the exclusion of all the models classified and published by the COMPETE Collaboration. The results obtained by TOTEM are indeed compatible with predictions of a colourless 3-gluon bound state exchange in the t-channel of proton-proton elastic scattering, as postulated by alternative theoretical models both in the Regge-like framework and in the modern QCD framework. This result has been confirmed, with a significance of 5.4σ, also by the comparison with the pp data measured by the D0 collaboration at Fermilab. In this contribution the TOTEM experiment results will be described, along with the actual experiment status, the future physics program for the LHC Run 3.