We calculate the unseen-but-true GRB-event rate from a current flux-limited sample of 33 GRBs with individually measured redshifts. We consider a GRBevent rate which is proportional to the star-formation rate, in view of the GRBSNe association in SN1998bw and GRB030329. By fitting a log-normal distribution of GRB peak-luminosities, we find a ratio 1/fr ≃ 450 for the true-to-observed GRB-event r...

We study the beaming effect of light for the case of increased-index photonic crystal (PhC) waveguides, formed through the omission of low-dielectric media in the waveguide region. We employ the finite-difference time-domain numerical method for characterizing the beaming effect and determining the mechanisms of loss and the overall efficiency of the directional emission. We find that, while th...

We analyze, theoretically and experimentally, the dynamics of the wavepackets in plasmonic beaming devices, and show that the beam evolution in this class of structures is a multiscale phenomenon, which initiates in the near-field proximity of the device, develops continuously over a new length scale many times the wavelength of the light, and is completed well into the far-field of the system....

Blazar radiation is dominated by a relativistic jet which can be modeled at first approximation using just two intrinsic parameters the Lorentz factor Γ and the viewing angle θ. Blazar jet observations are often beamed due to relativistic effects, complicating the understanding of these intrinsic properties. The most common way to estimate blazar Lorentz factors needs the estimation of apparent...

In a previous paper we presented measurements of the properties of jets and cores in a large sample of FRII radio galaxies with z < 0.3. Here we test, by means of Monte Carlo simulations, the consistency of those data with models in which the prominences of cores and jets are determined by relativistic beaming. We conclude that relativistic beaming is needed to explain the relationships between...

Recent observations have detected a number of young pulsars from the power peak in the γ-ray band to the incoherent photon peak in the optical/IR. We have made progress on the multiwavelength phenomenology of pulsar emission and beaming, but a wide variation of light curves between different objects and different energy bands makes the full story complex. I sketch here a ‘Unified Model’ of puls...

I briefly review much of the X-ray and optical data on the nature of the ULXs in nearby galaxies. I present new results on radio emission, finding that the radio is usually rather luminous and extended. I review the X-ray data on timing and spectra. There is no direct evidence in the X-ray data for either geometric or relativistic beaming and in 4 objects direct evidence against beaming. I argu...