Pair production can be triggered by high-intensity lasers via the Breit-Wheeler process. However, the straightforward laser-laser colliding for copious numbers of pair creation requires light intensities several orders of magnitude higher than possible with the ongoing laser facilities. Despite the numerous proposed approaches, creating high-energy-density pair plasmas in laboratories is still ...

Recently, we conducted a Very Large Telescope (VLT) large program to search for forming clusters by looking for overdensities of Lyα emitters around high redshift radio galaxies. In total seven proto-clusters were discovered, including a protocluster around the radio galaxy MRC 0316–257 at z ∼ 3.13. This structure has an excess of Lyα emitters by a factor of 3 as compared to the field, and the ...

Absorption measurements on solid conducting targets have been performed in s and p polarization with ultrashort, high-contrast Ti:sapphire laser pulses at intensities up to 5x10{16}W/cm{2} and pulse duration of 8 fs. The particular relevance of the reported absorption measurements lies in the fact that the extremely short laser pulse interacts with matter close to solid density during the entir...

We study theoretically the issue of externally driven excitations of standing kink waves and their resonant absorption into torsionally polarized m=1 waves in the coronal loops in pressureless plasmas. We use the ideal MHD equations, for which we develop an invariant imbedding method available in cylindrical geometry. We assume a sinusoidal density profile at the loop boundary where the densi...

We explore how the local environment is related to the redshift, type, and luminosity of active galactic nuclei (AGN). Recent simulations and observations are converging on the view that the extreme luminosity of quasars is fueled in major mergers of gas-rich galaxies. In such a picture, quasars are expected to be located in regions with a higher density of galaxies on small scales where merger...

Using cosmological hydrodynamical simulations, we investigate the prospects of the thermal Sunyaev-Zel’dovich (tSZ) effect to detect the missing baryons in the local universe. We find that at least 80% of the tSZ luminosity is generated in collapsed structures, and that ∼ 70% of the remaining diffuse tSZ luminosity (i.e., ∼ 15% of the total) comes from overdense regions with δgas >10, such as f...