The effect that cirrus clouds have upon the radiation emitted to space from the earth-atmosphere system is studied theoretically using a matrix method for computing the transfer of radiation in model cloud layers. The matrix method, which in essence is a generalization of a multi-streams approximation, is used to obtain the thermal radiation emitted by the clouds as well as their transmissiviti...

Introduction: Stereotactic Gamma Knife radiosurgery has been widely used for treating brain tumors. The scattered radiation outside of treatment field (peripheral dose) can induce the secondary cancer to specific organ. This paper investigated the absorbed dose to eyes, thyroid, heart, lung, breast and colon using a Monte Carlo technique for Mird phantom. We also study the ef...

UNLABELLED This work aimed to investigate the spatial distribution of scattered radiation doses induced by exposure to the portable X-ray, the C-arm machine, and to simulate the radiologist without a shield of lead clothing, radiation doses absorbed by medical staff at 2 m from the central exposure point. MATERIAL AND METHOD With the adoption of the Rando Phantom, several frequently X-rayed b...

Context. Theoretical arguments suggest that dust grains should grow in the dense cold parts of molecular clouds. Evidence of larger grains has so far been gathered in near/mid infrared extinction and millimeter observations. Interpreting the data is, however, aggravated by the complex interplay of density and dust properties (as well as temperature for thermal emission). Aims. Direct evidence o...

The high-redshift Universe contains luminous Lyα emitting sources such as galaxies and quasars. The emitted Lyα radiation is often scattered by surrounding neutral hydrogen atoms. We show that the scattered Lyα radiation obtains a high level of polarization for a wide range of likely environments of high-redshift galaxies. For example, the back-scattered Lyα flux observed from galaxies surround...

The terrestrial component of climate models requires computationally efficient algorithms for determining the multiscattered radiation contributing to its heating from solar radiation. Much of the vegetated land cover has strong 3D controls on its radiation. The scattering from a 3D object of isotropic scatters is formulated abstractly and an approach to solution is described in the context of ...

The spectra of the first galaxies and quasars in the Universe should be strongly absorbed shortward of their rest-frame Lyα wavelength by neutral hydrogen (HI) in the intervening intergalactic medium. However, the Lyα line photons emitted by these sources are not eliminated but rather scatter until they redshift out of resonance and escape due to the Hubble expansion of the surrounding intergal...

We computed the Debye series p=1 and p=2 terms of the Mie scattered intensity as a function of scattering angle and delay time for a linearly polarized plane wave pulse incident on a spherical dielectric particle and physically interpreted the resulting numerical data. Radiation shed by electromagnetic surface waves plays a prominent role in the scattered intensity. We determined the surface wa...