Related papers: The Extreme Physics Explorer
As the Imaging X-ray Polarimetry Explorer (IXPE) measures increasingly faint sources, the need for precise polarimetry extraction becomes paramount. In addition to previously described neural-net (NN) weights, we introduce here point-spread…
Several populations of neutron stars have surface magnetic fields above the critical strength of 4.4 x 10^{13} G where the electron cyclotron energy equals its rest mass energy. These include high-field rotation-powered pulsars, X-ray dim…
A deep all-sky imaging hard x-ray survey and wide-field monitor is needed to extend soft (ROSAT) and medium (ABRIXAS2) x-ray surveys into the 10-100 keV band (and beyond) at comparable sensitivity (~0.05 mCrab). This would enable discovery…
The X-ray emission of neutron stars enables a probe of their temperatures, geometries, and magnetospheric properties. The current number of X-ray emitting pulsars is insufficient to rule out observational biases that may arise from poorly…
The inspiral of a stellar-mass compact object into a massive ($\sim 10^{4}$-$10^{7} M_{\odot}$) black hole produces an intricate gravitational-wave signal. Due to the extreme-mass ratios involved, these systems complete $\sim…
X-ray polarimetry promises to give new information about high-energy astrophysical sources, such as binary black hole systems, micro-quasars, active galactic nuclei, and gamma-ray bursts. We designed, built and tested a hard X-ray…
With central densities as high as 5-10 times the nuclear saturation density, neutron stars exhibit extreme conditions that cannot be observed elsewhere. They are ideal astrophysical laboratories for probing the composition and properties of…
Astrophysical tests of general relativity belong to two categories: 1) "internal", i.e. consistency tests within the theory (for example, tests that astrophysical black holes are indeed described by the Kerr solution and its perturbations),…
We analyze the impact of future hard X-ray observations on the search for indirect signatures of particle dark matter in large extragalactic systems such as nearby clusters or groups of galaxies. We argue that the hard X-ray energy band…
The Square-Kilometre-Array (SKA) will be a radio telescope with a collecting area that will exceed that of existing telescopes by a factor of a hundred or so. This contribution summarises one of the key-science projects selected for the…
High Time Resolution Astrophysics (HTRA) concerns itself with observations on short scales normally defined as being lower than the conventional read-out time of a CCD. As such it is concerned with condensed objects such as neutron stars,…
Many experiments have searched for supersymmetric WIMP dark matter, with null results. This may suggest to look for more exotic possibilities, for example compact ultra-dense quark nuggets, widely discussed in literature with several…
The Imaging X-ray Polarimetry Explorer (IXPE), launched on December 9, 2021, enables X-ray polarimetric observations with unprecedented sensitivity in the 2-8 keV energy range. X-ray polarization allows us to test accretion disk, corona,…
With new forthcoming intense neutrino beams, for the study of neutrino oscillations, it is possible to consider other physics experiments that can be done with these extreme neutrino fluxes available close to the source.
A fraction of the active supermassive black holes at the centers of galaxies in our Universe are capable of launching extreme kiloparsec-long relativistic jets. These jets are known multiband (radio to $\gamma$-ray) and multimessenger…
Many instruments for astroparticle physics are primarily geared towards multi-messenger astrophysics, to study the origin of cosmic rays (CR) and to understand high-energy astrophysical processes. Since these instruments observe the…
Explosive astrophysical transients at cosmological distances can be used to place precision tests of the basic assumptions of relativity theory, such as Lorentz invariance, the photon zero-mass hypothesis, and the weak equivalence principle…
The aim of the present article is to evaluate the motion of charged test particles in the vicinity of a near-extremal rotating black hole in the presence of magnetic fields. Euler-Lagrange motion equations and effective potential methods…
Standard Model extensions often predict low-mass and very weakly interacting particles, such as the axion. A number of small-scale experiments at the intensity/precision frontier are actively searching for these elusive particles,…
We explore the influence of new physics on extremely high energy cosmic ray (EXCER) particles. In particular, we devote our mind to one example of new physics, unparticle stuff, on one specific process that EXECRs participate in, photopion…