Related papers: Polarization mesurements of gamma ray bursts and a…
The detection by the LHAASO Collaboration of the gamma-ray burst GRB 221009A at redshift $z = 0.151$ with energies up to $(13-18) \, \rm TeV$ challenges conventional physics. Photons emitted with energies above $10 \, \rm TeV$ at this…
Axionlike particles (ALPs) are hypothetical light (sub-eV) bosons predicted in some extensions of the Standard Model of particle physics. In astrophysical environments comprising high-energy gamma rays and turbulent magnetic fields, the…
The degree and the temporal evolution of linear polarization in the prompt and afterglow emission of gamma-ray bursts is a very robust diagnostic of some key features of gamma-ray bursts jets and their micro and macro physics. In this…
Axion-like particles (ALPs) are hypothetical pseudoscalar bosons that arise in many extensions of the Standard Model and are well-motivated dark matter candidates. Nearby massive stars in the late stages of stellar evolution provide a…
Simultaneous $\gamma$-ray measurements of gamma-ray burst (GRB) spectra and polarization offer a unique way to determine the underlying emission mechanism(s) in these objects as well as probing the particle acceleration mechanism(s) that…
X-ray flares, lasting for $\sim 100 - 1000$ s in the X-ray band, are often observed following gamma-ray bursts (GRBs). The physical origin of X-ray flares is still unknown merely with the temporal/spectral information. On the other hand,…
Observations by the {\RHESSI} satellite of large polarization of the prompt $\gamma$-ray emission from the Gamma Ray Burst GRB021206 \citep{coburn03} imply that the magnetic field coherence scale is larger than the size of the visible…
A possibility to measure the energy and polarization distributions of high intensity gamma-beams is considered. This possibility is based on measurements of the number of electron-pozitron pairs in such media as laser waves and single…
One interpretation of the unexplained signature observed in the PVLAS experiment invokes a new axion-like particle (ALP) with a two-photon vertex, allowing for photon-ALP oscillations in the presence of magnetic fields. In the range of…
We propose using the upcoming Cosmic Microwave Background (CMB) ground based experiments to detect the signal of ALPs (Axion like particles) interacting with magnetic fields in galaxy clusters. The conversion between CMB photons and ALPs in…
Well-motivated extensions of the standard model predict ultra-light and fundamental pseudo-scalar particles (e.g., axions or axion-like particles: ALPs). Similarly to the Primakoff-effect for axions, ALPs can mix with photons and…
Axion Like Particles (ALPs), postulated to solve the strong-CP problem, are predicted to couple with photons in the presence of magnetic fields, which may lead to a significant change in the observed spectra of gamma-ray sources such as…
Oscillations from high energy photons into light pseudoscalar particles in an external magnetic field are expected to occur in some extensions of the standard model. It is usually assumed that those axionlike particles (ALPs) could produce…
Over half a century from the discovery of gamma-ray bursts (GRBs), the dominant radiation mechanism responsible for their bright and highly variable prompt emission remains poorly understood. Spectral information alone has proven…
Hypothetical oscillations of probe photons into axion-like particles might be revealed by exploiting the strong fields of high-intensity laser pulses. Considering an arbitrary plane-wave background, we determine the polarization tensor…
We study the polarization properties of the prompt emission of gamma-ray bursts produced by fragmented fireballs. Such fireballs, known in the literature under various names, are made by the superposition of many individual blobs, each of…
The optical afterglows of the gamma ray bursts can be strongly polarized, in principle up to tens of percents, if: (i) the afterglow is synchrotron radiation from an ultra-relativistic blast, (ii) the blast is beamed during the afterglow…
While the dominant radiation mechanism gamma-ray bursts (GRBs) remains a question of debate, synchrotron emission is one of the foremost candidates to describe the multi-wavelength afterglow observations. As such, it is expected that GRBs…
As radio polarised emission from astrophysical objects traverse through foreground magnetised plasma, the physical conditions along the lines of sight are encrypted in the form of Rotation Measure (RM). We performed broadband…
This paper reviews the development status of GRAPE (the Gamma-Ray Polarimeter Experiment), a hard X-ray Compton Polarimeter. The purpose of GRAPE is to measure the polarization of hard X-rays in the 50-300 keV energy range. We are…