We consider a scheme for coherent imaging that exploits the classical correlation of two beams obtained by splitting incoherent thermal radiation. This case is analyzed in parallel with the configuration based on two entangled beams produced by parametric down-conversion, and a precise formal analogy is pointed out. This analogy opens the possibility of using classical beams from thermal radiat...

In this paper, we investigate thermal equilibrium in string gas cosmology which is dominated by closed string. We consider two interesting regimes, Hagedorn and radiation regimes. We find that for short strings in small radius of Hagedorn regime very large amount of energy requested to have thermal equilibrium but for long strings in such system a few energy is sufficient to have thermal equili...

A large heat load caused by thermal radiation through a metal shield pipe was observed in a cooling test of a cryostat for a prototype of a cryogenic interferometric gravitational wave detector. The heat load was approximately 1000 times larger than the value calculated by the Stefan-Boltzmann law. We studied this phenomenon by simulation and experiment and found that it was caused by the condu...

Aluminum alloys, which serve as heat sink in light-emitting diode (LED) lighting, are often inherent with a high thermal conductivity, but poor thermal total emissivity. Thus, high emissive coatings on the Al substrate can enhance the thermal dissipation efficiency of radiation. In this study, the ultrasonic mechanical coating and armoring (UMCA) technique was used to insert various ceramic com...

This research analyses upward long-wave radiation flux density from urban surfaces using a high-resolution thermal-infrared (TIR) camera and meteorological measurements in the city of Berlin, Germany. We report spatiotemporal patterns of the difference between upward long-wave radiation flux density from courtyard surfaces and the roof. Thermal patterns show persistence effects due to shadow, s...

We consider stochastic particle acceleration in plasmas around stellar mass black holes to explain the emissions above 1 MeV from Galactic black hole candidates. We show that for certain parameter regimes, electrons can overcome Coulomb losses and be accelerated beyond the thermal distribution to form a new population, whose distribution is broad and usually not a power law; the peak energy of ...

We propose an emission mechanism of prompt gamma-ray bursts (GRBs) that can reproduce the observed non-thermal spectra with high radiative efficiencies, > 50%. Internal dissipation below a photosphere can create a radiation-dominated thermal fireball. If e pairs outnumber protons, radiative acceleration of e pairs drives the two-stream instabilities between pairs and protons, leading to the “pr...

ABSTRACT The use of a thermoelectric generator (TEG) in generating useful power from solar thermal energy is demonstrated. This device represents a portable and autonomous power generation system operating from solar power, capable of powering micro/nano systems. The TEG was integrated with a micro solar thermal collector plate to enhance the thermal radiation absorption capacity of the hot sid...

A study has been carried out to analyze the effect of Magnetic field flow in a porous medium with consider thermal radiation and suction/injection over a permeable stretching wall. We consider wall boundary conditions are distribution of wall temperature, in addition to momentum, both first and second laws of the thermodynamics analyses of the problem are investigated. A set of solution to the ...