where i, r, and t label the incident, reflected, and transmitted waves, respectively. The solution is based on the fact that eq. (1) holds separately for each polarization of the emitted radiation, and is also independent of the angle of the radiation. This result is implicit in Planck’s derivation [5] of Kirchhoff’s law of radiation, and is stated explicitly in [6]. That law describes the ther...

In this Letter we demonstrate, for the first time, selective thermal emitters based on metamaterial perfect absorbers. We experimentally realize a narrow band midinfrared (MIR) thermal emitter. Multiple metamaterial sublattices further permit construction of a dual-band MIR emitter. By performing both emissivity and absorptivity measurements, we find that emissivity and absorptivity agree very ...

It is well known that the efficiency of thermodynamic solar plants increases with the working temperature. At present the main limit in temperature upscaling is the absorber capability to withstand high temperatures. The ideal solar absorber works at high temperatures, has a low thermal emissivity and a high absorptivity in the solar spectral range . The paper reports on the high temperature em...

We discuss the color-superconductivity and its effect on the cooling behavior of strange quark stars. The neutrino emissivity and specific heat of quark matter are calculated within the BCS theory. In the superconducting phase, the emissivity decreases and causes suppression of the cooling rate. It is shown that the phase transition leads to a sudden discontinuous suppression of the cooling rat...

The theory of stellar structure can be used to identify the most plausible mechanisms for the irradiance variations associated with the solar cycle. Changes in surface emissivity, i.e. the reduced cooling in spots and enhanced emission by small scale magnetic fields, are the most effective mechanisms and account for most of the observed variation. Helioseismology will soon be able to test the c...

Surface emissivity is a measure of inherent efficiency of land surface. It is applied to convert heat energy into radiant energy. In this study, an unmixing pixel based algorithm was proposed to compute pixel effective emissivity for Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data within Beijing, China. In this paper, vegetation, together with water and 3 kinds of ma...

This paper presents modifications to the linear kernel bidirectional reflectance distribution function (BRDF) models from Roujean et al. and from Wanner et al. that extend the spectral range into the thermal infrared (TIR). Our application is to synthesize the TIR optical properties of a scene pixel from laboratory component measurements. The angular reflectance and emissivity are needed to con...

We measured emissivity of sample presenting panel of ALMA antenna using Band-10 heterodyne SIS receiver as antenna switching balanced radiometer with 8 GHz instantaneous bandwidth. Receiver noise temperature measured with 80 K/300 K antenna loads was ≈560 K (DSB). Emissivity of the surface is detected at LO frequency about 840 GHz via the imbalance of the antenna switch due to extra reflection ...