It is shown that a generic black hole solution of the SU (2) Einstein-Yang-Mills (EYM) equations develops a new type of an infinitely oscillating behavior near the singularity. Only for certain discrete values of the event horizon radius exceptional solutions exist possessing an inner structure of the Schwarzschild or Reissner-Nordström type. 04.20.Jb, 97.60.Lf, 11.15.Kc Discovered soon after the regular Bartnik-McKinnon (BK) solutions [1], EYM black holes (BH) [2][3][4] provided new insights into the BH physics related to the no-hair and uniqueness theorems [5]. They share sphaleronic properties of the BK particle-like solutions [6] and also exhibit an unusual discreteness ('quantization' of the YM field on the event horizon) due to a singular non-linear boundary value problem in the domain between the horizon and the asymptotically flat (AF) infinity. Still, the existing knowledge of the EYM BH's (unlike the BK objects) is incomplete since only external solutions have been constructed so far (though a qualitative discussion of inner solutions is available [3]). Here we present brief results of our investigation of the interior structure of the EYM BH's which reveal new surprising features due to coupling of non-linear fields to gravity.Assume the static spherically symmetric magnetic ansatz for the YM potential(T ϕ,θ are spherical projections of the SU (2) generators) and the following parametrization of the metricwhere dΩ 2 = dθ 2 + sin 2 θdϕ 2 , and ∆, σ depend on r. The field equations include a coupled system for W , ∆where V = (W 2 − 1), F = 1 − V 2 /r 2 , and a decoupled equation for σ:These equations admit BH solutions in the domain r ≥ r h for any radius of the event horizon r h . The solutions are specified by the number n ∈ N of nodes of W thus forming a discrete set for each r h . Although it is not guaranteed a priori that the chart (1) is extendible to the full region r < r h , for AF solutions we did not meet any singularity in the interior region unless the genuine one r = 0 is reached. In terms of coordinates (1) one can find three distinct local power series solutions. The first one is Schwarzschild-like (S), it corresponds to the vacuum value of the YM field |W (0)| = 1. Using the mass function m(r), ∆ = r 2 − 2mr, one gets [3]where m 0 , b are (the only) free parameters. The second is the Reissner-Nordström (RN) type of solution which can be found assuming the leading term of ∆ to be a positive constant. This requires W (0) = W 0 = ±1, 0 and gives [3]what corresponds to the RN metric of the mass m 0 and the (magnetic) charge. The expansion contains three free parameters W 0 , m 0 , c.We have also found the third local power series solution assuming a negative value for ∆(0) (i.e. imaginary P ):Here there is only one free parameter (W 0 ) for W , ∆. The corresponding space-time near the singularity is conformal to the cylinder (after a time rescaling):However, one may suspect that such asymptotics can not correspond to a generic BH. Imposing 'boundary conditions' in the singularity we obta...
The Probe Of Extreme Multi-Messenger Astrophysics (POEMMA) is designed to accurately observe ultra-high-energy cosmic rays (UHECRs) and cosmic neutrinos from space with sensitivity over the full celestial sky. POEMMA will observe the air fluorescence produced by extensive air showers (EASs) from UHECRs and potentially UHE neutrinos above 20 EeV. Additionally, POEMMA has the ability to observe the Cherenkov signal from upward-moving EASs induced by Earth-interacting tau neutrinos above 20 PeV. The POEMMA spacecraft are designed to quickly re-orientate to follow up transient neutrino sources and obtain currently unparalleled neutrino flux sensitivity. Developed as a NASA Astrophysics Probe-class mission, POEMMA consists of two identical satellites flying in loose formation in 525 km altitude orbits. Each POEMMA instrument incorporates a wide field-of-view (45∘) Schmidt telescope with an optical collecting area of over 6 m2. The hybrid focal surface of each telescope includes a fast (1 μs) near-ultraviolet camera for EAS fluorescence observations and an ultrafast (10 ns) optical camera for Cherenkov EAS observations. In a 5-year mission, POEMMA will provide measurements that open new multi-messenger windows onto the most energetic events in the universe, enabling the study of new astrophysics and particle physics at these extreme energies.
The origin and nature of extreme energy cosmic rays (EECRs), which have energies above the 5 · 10 19 eV, the Greisen-Zatsepin-Kuzmin (GZK) energy limit, is one of the most interesting and complicated problems in modern cosmic-ray physics. Existing ground-based detectors have helped to obtain remarkable results in studying cosmic rays before and after the GZK limit, but have also produced some contradictions in our understanding of cosmic ray mass composition. Moreover, each of these detectors covers only a part of the celestial sphere, which poses problems for studying the arrival directions of EECRs and identifying their sources. As a new generation of EECR space detectors, TUS (Tracking Ultraviolet Set-up), KLYPVE and JEM-EUSO, are intended to study the most energetic cosmic-ray particles, providing larger, uniform exposures of the entire celestial sphere. The TUS detector, launched on board the Lomonosov satellite on April 28, 2016, from Vostochny Cosmodrome in Russia, is the first of these. It employs a single-mirror optical system and a photomultiplier tube matrix as a photodetector and will test the fluorescent method of measuring EECRs from space. Utilizing the Earth's atmosphere as a huge calorimeter, it is expected to detect EECRs with energies above 10 20 eV. It will also be able to register slower atmospheric transient events: atmospheric fluorescence in electrical discharges of various types including precipitating electrons escaping the magnetosphere and from the radiation of meteors passing through the atmosphere. We describe the design of the TUS detector and present results of different ground-based tests and simulations.
Abstract. TUS (Tracking Ultraviolet Set-up), the first orbital detector of extreme energy cosmic rays (EECRs), those with energies above 50 EeV, was launched into orbit on April 28, 2016, as a part of the Lomonosov satellite scientific payload. The main aim of the mission is to test a technique of registering fluorescent and Cherenkov radiation of extensive air showers generated by EECRs in the atmosphere with a space telescope. We present preliminary results of its operation in a mode dedicated to registering extensive air showers in the period from August 16, 2016, to November 4, 2016. No EECRs have been conclusively identified in the data yet, but the diversity of ultraviolet emission in the atmosphere was found to be unexpectedly rich. We discuss typical examples of data obtained with TUS and their possible origin. The data is important for obtaining more accurate estimates of the nocturnal ultraviolet glow of the atmosphere, necessary for successful development of more advanced orbital EECR detectors including those of the KLYPVE (K-EUSO) and JEM-EUSO missions.
n this paper we describe the main characteristics of the JEM-EUSO instrument. The Extreme Universe Space Observatory on the Japanese Experiment Module (JEM-EUSO) of the International Space Station (ISS) will observe Ultra High-Energy Cosmic Rays (UHECR) from space. It will detect UV-light of Extensive Air Showers (EAS) produced by UHECRs traversing the Earth's atmosphere. For each event, the detector will determine the energy, arrival direction and the type of the primary particle. The advantage of a space-borne detector resides in the large field of view, using a target volume of about 10(12) tons of atmosphere, far greater than what is achievable from ground. Another advantage is a nearly uniform sampling of the whole celestial sphere. The corresponding increase in statistics will help to clarify the origin and sources of UHECRs and characterize the environment traversed during their production and propagation. JEM-EUSO is a 1.1 ton refractor telescope using an optics of 2.5 m diameter Fresnel lenses to focus the UV-light from EAS on a focal surface composed of about 5,000 multi-anode photomultipliers, for a total of a parts per thousand integral 3a <...10(5) channels. A multi-layer parallel architecture handles front-end acquisition, selecting and storing valid triggers. Each processing level filters the events with increasingly complex algorithms using FPGAs and DSPs to reject spurious events and reduce the data rate to a value compatible with downlink constraints
TUS (Tracking Ultraviolet Set-up) is the world's first orbital detector of ultra-high-energy cosmic rays (UHECRs). It was launched into orbit on 28th April 2016 as a part of the scientific payload of the Lomonosov satellite. The main aim of the mission was to test the technique of measuring the ultraviolet fluorescence and Cherenkov radiation of extensive air showers generated by primary cosmic rays with energies above ∼100 EeV in the Earth atmosphere from space. During its operation for 1.5 years, TUS registered almost 80,000 events with a few of them satisfying conditions anticipated for extensive air showers (EASs) initiated by UHECRs. Here we discuss an event registered on 3rd October 2016. The event was measured in perfect observation conditions as an ultraviolet track in the nocturnal atmosphere of the Earth, with the kinematics and the light curve similar to those expected from an EAS. A reconstruction of parameters of a primary particle gave the zenith angle around 44̂ but an extreme energy not compatible with the cosmic ray energy spectrum obtained with ground-based experiments. We discuss in details all conditions of registering the event, explain the reconstruction procedure and its limitations and comment on possible sources of the signal, both of anthropogenic and astrophysical origin. We believe this detection represents a significant milestone in the space-based observation of UHECRs because it proves the capability of an orbital telescope to detect light signals with the apparent motion and light shape similar to what are expected from EASs. This is important for the on-going development of the future missions KLYPVE-EUSO and POEMMA, aimed for studying UHECRs from space.
Meteor and fireball observations are important to derive the inventory and physical characterization of the population of small solar system bodies orbiting in the vicinity of the Earth. After decades of ground-based activities, the proposed JEM-EUSO mission has some chances to become the first operational space-based platform having among its scientific objectives the observation of fireball and meteor events. The observing strategy developed to detect these phenomena, which are eminently "slow" events with respect to the extremely energetic cosmic ray events which are the primary objective of the mission, can prove to be very suitable also for the possible detection of nuclearites, an exciting possibility which enhances the overall scientific rationale of JEM-EUSO, and suggests that the planned observation of slow events may be very interesting in many respects.
In this paper we describe the observational principle and the expected performances of JEM-EUSO. Designed as the first mission to explore the ultra-high energy universe from space, JEM-EUSO monitors the Earth's atmosphere at night to record the UV (300-430 nm) tracks generated by the Extensive Air Showers. We present the expected geometrical aperture and annual exposure in nadir and tilt modes for Ultra-High Energy Cosmic Rays as a function of the ISS altitude.
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