P. Bobik

Slovak Academy of Sciences | SAV · Institute of Experimental Physics

We present a tool for simulations of cosmic ray trajectories in the magnetosphere called COR (Cut-Off Rigidity). The COR tool provides a framework offering a wide range of functionalities and the possibility to realize extensive simulations at scalable multicore/multinode systems. COR is available at https://cor.crmodels.org. Code used by COR for s...

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...

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.

The propagation of cosmic rays through the heliosphere has been solved for more than half a century by stochastic methods based on Ito’s lemma. This work presents the estimation of statistical error of solution of Fokker–Planck equation by the 1D backward in time stochastic differential equations method. The error dependence on simulation statistic...

In this article, we focus on the modulation of cosmic rays at high energies. The aim is to determine the limits of the ability of the heliosphere to modulate the intensities of cosmic rays in the inner heliosphere. We address the following questions: how large is the variation in cosmic rays intensities at high energies, i.e. close to 50, 100 and 2...

Slovak research in space physics, geophysics and astronomy for period 2018-2019

Space experiments with Slovak participation for period 2018 - 2019.

A new theoretical approach to describe the physical processes of energy particle propagation is proposed. This approach is based on the analytically iterative method for solving closed cosmic ray (CR) modulation problems, which was proposed by Shakhov and Kolesnyk. First, we have applied the approach on a simple model of the heliosphere, wherein th...

Compilation of papers presented by the JEM-EUSO Collaboration at the 36th International Cosmic Ray Conference (ICRC), held July 24 through August 1, 2019 in Madison, Wisconsin.

The main goal of The Extreme Universe Space Observatory on a Super Pressure Balloon (EUSO-SPB1) was to observe from above extensive air showers caused by ultra-high energy cosmic rays. EUSO-SPB1 uses a fluorescence detector that observes the atmosphere in a nadir observation mode from a near space altitude. During the 12-day flight, an onboard firs...

The night time airglow is a dynamic phenomenon that acts as a background for the detection of the extensive air shower (EAS) fluorescence. It is a mandatory task to monitor this background for the ground-based telescopes and for the planned space-based telescopes, dedicated to observe the EAS events induced by the ultra-high energy cosmic rays. To...

The JEM-EUSO (Joint Experiment Missions for the Extreme Universe Space Observatory) program aims at developing Ultra-Violet (UV) fluorescence telescopes for efficient detections of Extensive Air Showers (EASs) induced by Ultra-High Energy Cosmic Rays (UHECRs) from satellite orbit. In order to demonstrate key technologies for JEM-EUSO, we constructe...

Airglow is a dynamic phenomenon which depends on the geographical location, season, local time, geomagnetic activity, and other conditions. Variations in UV nighttime airglow (300–500 nm) caused by magnetospheric disturbances for several selected points around globe are presented in this study. Used airglow intensity data were evaluated in empirica...

EUSO-Balloon is a pathfinder mission for the Extreme Universe Space Observatory onboard the Japanese Experiment Module (JEM-EUSO). It was launched on the moonless night of the 25th of August 2014 from Timmins, Canada. The flight ended successfully after maintaining the target altitude of 38 km for five hours. One part of the mission was a 2.5 hour...

EUSO-TA is a ground-based telescope, installed at the Telescope Array (TA) site in Black Rock Mesa, Utah, USA. This is the first detector to use a Fresnel lens based optical system and multi-anode photomultipliers (64 channels per tube, 2304 channels encompassing a 10.6° × 10.6° field of view) for detection of Ultra High Energy Cosmic Rays (UHECR)....

The article summarizes activities and results regarding pattern recognition for the JEM-EUSO experiment done by Slovak group of JEM-EUSO collaboration. The activities include estimation of trigger probability of false positives and reconstruction of simulated UHECR showers in UV background using Euso Simulation and Analysis Framework (ESAF). The Ho...

The development of an analytically iterative method for solving steady-state as well as unsteady problems of Cosmic Ray (CR) modulation is proposed. Iterations for obtaining the solutions are constructed for the spherically symmetric form of the CR propagation equation. The main solution of the considered problem consists of the zero order solution...

JEM-EUSO is a space mission designed to investigate Ultra-High Energy Cosmic Rays and Neutrinos (E>5⋅10¹⁹eV) from the International Space Station (ISS). Looking down from above its wide angle telescope is able to observe their air showers and collect such data from a very wide area. Highly specific trigger algorithms are needed to drastically reduc...

We summarize the state of the art of a program of UV observations from space of meteor phenomena, a secondary objective of the JEM-EUSO international collaboration. Our preliminary analysis indicates that JEM-EUSO, taking advantage of its large FOV and good sensitivity, should be able to detect meteors down to absolute magnitude close to 7. This me...

The cosmic rays propagation inside the heliosphere is well described by a transport equation introduced by Parker in 1965. To solve this equation, several approaches were followed in the past. Recently, a Monte Carlo approach became widely used in force of its advantages with respect to other numerical methods. In this approach the transport equati...

The EUSO-TA detector is a pathfinder for the JEM-EUSO project and is currently installed in Black Rock Mesa (Utah) on the site of the Telescope Array fluorescence detectors. Aim of this experiment is to validate the observation principle of JEM-EUSO on air showers measured from ground. The experiment gets data in coincidence with the TA triggers to...

COSPAR report

The Extreme Universe Space Observatory on board the Japanese Experiment Module of the International Space Station, JEM-EUSO, is being designed to search from space ultra-high energy cosmic rays. These are charged particles with energies from a few 1019 eV to beyond 1020 eV, at the very end of the known cosmic ray energy spectrum. JEM-EUSO will also...

Space-based detectors for the study of extreme energy cosmic rays (EECR) are being prepared as a promising new method for detecting highest energy cosmic rays. A pioneering space device – the “tracking ultraviolet set-up” (TUS) – is in the last stage of its construction and testing. The TUS detector will collect preliminary data on EECR in the cond...

The Extreme Universe Space Observatory on the Japanese Experiment Module (JEM-EUSO) on board the International Space Station (ISS) is the first space-based mission worldwide in the field of Ultra High-Energy Cosmic Rays (UHECR). For UHECR experiments, the atmosphere is not only the showering calorimeter for the primary cosmic rays, it is an essenti...

The variability of cosmic rays (CRs) observed at selected European neutron monitors (NMs) around moderate geomagnetic disturbances, namely during the intervals (a) DOY 49-51 in 2014, (b) DOY 58-59 in 2014, (c) DOY 238-240 in 2014 and (d) DOY 6-8 in 2015 is discussed. Assuming the primary spectra of the CREME96 model, the yield function and geomagne...

EUSO-Balloon is a pathfinder for JEM-EUSO, the Extreme Universe Space Observatory which is to be hosted on-board the International Space Station. As JEM-EUSO is designed to observe Ultra-High Energy Cosmic Rays (UHECR)-induced Extensive Air Showers (EAS) by detecting their ultraviolet light tracks “from above”, EUSO-Balloon is a nadir-pointing UV t...

The cosmic rays modulation inside the heliosphere is well described by a transport equation introduced by Parker in 1965. To solve this equation several approaches were followed in the past. Recently the Monte Carlo approach becomes widely used in force of his advantages with respect to other numerical methods. In the Monte Carlo approach, the tran...

for the JEM-EUSO Collaboration JEM-EUSO experiment will observe UV light created by extensive air showers initiated by ultra high energy cosmic rays (UHECR). Reconstruction of UHECR particle direction from detected signal depends also on the level of signal background, which can vary in time and with location. We developed an alternative pattern re...

Ultra high energy photons and neutrinos are carriers of very important astrophysical information. They may be produced at the sites of cosmic ray acceleration or during the propagation of the cosmic rays in the intergalactic medium. In contrast to charged cosmic rays, photon and neutrino arrival directions point to the production site because they...

Mounted on the International Space Station(ISS), the Extreme Universe Space Observatory, on-board the Japanese Experimental Module (JEM-EUSO), relies on the well established fluorescence technique to observe Extensive Air Showers (EAS) developing in the earth’s atmosphere. Focusing on the detection of Ultra High Energy Cosmic Rays (UHECR) in the de...

The main goal of the JEM-EUSO experiment is the study of Ultra High Energy Cosmic Rays (UHECR, 1019−1021e V), but the method which will be used (detection of the secondary light emissions induced by cosmic rays in the atmosphere) allows to study other luminous phenomena. The UHECRs will be detected through the measurement of the emission in the ran...

The Extreme Universe Space Observatory (EUSO) on–board the Japanese Experimental Module (JEM) of the International Space Station aims at the detection of ultra high energy cosmic rays from space. The mission consists of a UV telescope which will detect the fluorescence light emitted by cosmic ray showers in the atmosphere. The mission, currently de...

During solar events (such as flares or CME), energetic protons are accelerated in interplanetary medium. These particles are called briefly SEP (solar energetic particles). We estimated the SEP contribution to solar wind pressure. We used data collected by ACE and GOES, in particular during 4 periods, each one of 15 days. Each period is centered on...

Our codes to evaluate the solar modulation of Galactic Cosmic Rays (HelMod) and to trace the the charged particles inside the Earth magnetosphere (GeoMag) have been implemented as webmodels in the two websites, helmod.org and geomagsphere.org. HelMod model uses a 2D Monte Carlo approach to solves the Parker transport equation, obtaining a modulated...

We developed a backtracing code for Cosmic Rays trajectory reconstruction in the Earth Magnetosphere with last models of Internal (IGRF-11) and External (Tsyganenko 1996 and 2005) field components. Particles can be reconstructed, in case of allowed trajectory, as Primary Cosmic Rays if they reach the outer boundary (magnetopause) or, in case of for...

In this paper we describe the expected performance of JEM-EUSO. Designed as the first mission to explore the ultra-high energy universe from space, JEM-EUSO will monitor the Earth’s atmosphere at night to record the UV (300–430 nm) tracks generated by the extensive air showers produced by ultra-high energy primary particles developing in the atmosp...

COSPAR Report

Designed as the first mission to explore the ultra-high energy universe from space, JEM-EUSO observes the Earth's atmosphere at night to record the ultraviolet tracks generated by the extensive air showers. We present the expected geometrical aperture and annual exposure in the nadir and tilt modes for ultra-high energy cosmic rays observation as a...

The JEM-EUSO experiment at the International Space Station will detect the Earth night side UV light produced by UHECR due to their interaction with the atmosphere. The estimation of UV background in different conditions is necessary to precise the estimation of the experiment’s operational efficiency. In this article, we estimate an intensity of U...

Energetic (suprathermal) solar particles, accelerated in the interplanetary medium, contribute to the solar wind pressure, in particular during high solar activity periods. We estimated the effect of the increase of solar wind pressure due to suprathermal particles on magnetospheric transmissivity of galactic cosmic rays in the case of one recent s...

We implemented a website to deal with main effects on Cosmic Ray access to the Earth, i.e. the Solar Modulation and the Geomagnetic Field effect. In helmod.org the end user can easily access a web interface to results catalog of the HelMod Monte Carlo Code. This Model uses a Monte Carlo Approach to solves the Parker Transport Equation, obtaining a...

The Cosmic Rays propagation was studied in details using the HelMod-2D Monte Carlo code, that includes a general description of the diffusion tensor, and polar magnetic-field. The Numerical Approach used in this work is based on a set of Stochastic Differential Equations fully equivalent to the well know Parker Equation for the transport of Cosmic...

In this paper we describe the requirements and the expected performances of JEM-EUSO. Designed as the first mission to explore the Ultra High Energy Universe from space, JEM-EUSO will monitor the earth's atmosphere at night to record the UV (300-400 nm) tracks generated by the Extensive Air Showers produced by Ultra High Energy primaries propagatin...

We evaluate the exposure during nadir observations with JEM-EUSO, the Extreme Universe Space Observatory, on-board the Japanese Experiment Module of the International Space Station. Designed as a mission to explore the extreme energy Universe from space, JEM-EUSO will monitor the Earth's nighttime atmosphere to record the ultraviolet light from tra...

We evaluate the exposure during nadir observations with JEM-EUSO, the Extreme Universe Space Observatory, on-board the Japanese Experiment Module of the International Space Station. Designed as a mission to explore the extreme energy Universe from space, JEM-EUSO will monitor the Earth's nighttime atmosphere to record the ultraviolet light from tra...