Related papers: Astrophysics: Most distant cosmic blast seen
We draw attention to observational evidence indicating that a substantial fraction of the well-known cosmic celestial diffuse ultraviolet background radiation field is actually due not to dust-scattered starlight, but rather---considering…
The discovery of radio pulsars over a half century ago was a seminal moment in astronomy. It demonstrated the existence of neutron stars, gave a powerful observational tool to study them, and has allowed us to probe strong gravity, dense…
The origin of the highest energy cosmic rays is still unknown. The discovery of their sources will reveal the workings of the most energetic astrophysical accelerators in the universe. Current observations show a spectrum consistent with an…
Observations made using large ground-based and space-borne telescopes have probed cosmic history all the way from the present-day to a time when the Universe was less than a tenth of its present age. Earlier on lies the remaining frontier,…
Cosmic rays represent one of the most fascinating research themes in modern astronomy and physics. After almost a century since their discovery, a huge amount of scientific literature has been written on this topic and it is not always easy…
The understanding of the nature of ultra-high-energy cosmic rays is one of the most intriguing open questions for current and future observatories. These particles are expected to be accelerated in extragalactic sources. Because of their…
In 2007 we were part of a team that discovered the so-called ``Lorimer Burst'', the first example of a new class of objects now known as fast radio bursts (FRBs). These enigmatic events are only a few ms in duration and occur at random…
A century ago, nuclear physics entered astrophysics, giving birth to a new field of science referred to as "Nuclear Astrophysics". With time, it developed at an impressive pace into a vastly inter- and multidisciplinary discipline bringing…
The study of high energy cosmic rays is a diversified field of observational and phenomenological physics addressing questions ranging from shock acceleration of charged particles in various astrophysical objects, via transport properties…
Fast radio bursts (FRBs) are millisecond-timescale bursts of coherent radio emission that are luminous enough to be detectable at cosmological distances. In this review I describe the discovery of FRBs, subsequent advances in our…
Cosmic rays (CRs) are the probes of the deep space. They allow us to study particle acceleration, chemical composition of the interstellar medium, and global properties of our Galaxy. However, until recently studies of CRs were similar to…
Multi-messenger astronomy provides for the observation of the same astronomical event with different kind of telescopes at the same time: optical observations, X-rays, gamma-ray bursts, neutrinos and, most recently, gravitational waves are…
Understanding the formation and evolution of the first stars and galaxies represents one of the most exciting frontiers in astronomy. Since the universe was filled with neutral hydrogen at early times, the most promising method for…
The existence of a thermodynamic arrow of time in the present universe implies that the initial state of the observable portion of our universe at (or near) the ``big bang'' must have been very ``special''. We argue that it is not plausible…
Gamma-Ray Bursts (GRBs) - short bursts of 100-1MeV photons arriving from random directions in the sky are probably the most relativistic objects discovered so far. Still, somehow they did not attract the attention of the relativistic…
Cosmic rays are the most outstanding example of accelerated particles. They are about 1\% of the total mass of the Universe, so that cosmic rays would represent by far the most important energy transformation process of the Universe.…
Although cosmic rays were discovered a century ago, we do not know where or how they are accelerated. There is a realistic hope that the oldest problem in astronomy will be solved soon by ambitious experimentation: air shower arrays of…
Almost three decades ago, the Fly's Eye experiment recorded the most energetic cosmic-ray ever observed. With an energy of 320 EeV, this event is well beyond the suppression region of the ultra-high energy cosmic rays (UHECR) spectrum.…
Gamma-Ray Bursts represent unique tools to study the early phases of cosmic evolution, the formation of the first stars and galaxies. Absorption line spectra of these sources located in the Epoch of Reionization might provide us with key…
Gamma Ray Bursts (GRBs) are the most explosive events after the big bang: their energy output corresponds to a sizeable fraction of a solar mass entirely converted into energy in a few seconds. Although many questions about their…