The presence of metals in hot cluster gas and in Lyα absorbers, as well as the mass-metallicity relation of observed galaxies, suggest that galaxies lose a significant fraction of their metals to the intergalactic medium (IGM). Theoretical studies of this process have concentrated on metal removal by dynamical processes or supernova-driven winds. Here, we investigate the enrichment of the IGM b...

A de-orbiting strategy for small satellites, in particular CubeSats, is proposed which exploits the effect of solar radiation pressure to increase the spacecraft orbit eccentricity so that the perigee falls below an altitude where atmospheric drag will cause the spacecraft orbit to naturally decay. This is achieved by fitting the spacecraft with an inflatable reflective balloon. Once this is fu...

We describe an experimental conceptual design for observation and reduction of radiation pressure noise. The radiation pressure noise is increased in a high finesse cavity with a small mass mirror. In our experiment a Fabry-Perot Michelson interferometer with a homodyne detection scheme will be built with Fabry-Perot cavities of finesse of 10000 containing suspended mirrors of 23mg. To observe ...

A patient presented with symptoms and signs of raised intracranial pressure and increasing focal deficit 13 months after stereotactic radiosurgical treatment of an arteriovenous malformation (AVM). Computed Tomography (CT) showed a mass lesion at the site of the previous abnormality typical of radiation necrosis, but with features identical to those of a malignant neoplasm. Biopsy confirmed cer...

We study numerically the deformation of sessile dielectric drops immersed in a second fluid when submitted to the optical radiation pressure of a continuous Gaussian laser wave. Both drop stretching and drop squeezing are investigated at steady state where capillary effects balance the optical radiation pressure. A boundary integral method is implemented to solve the axisymmetric Stokes flow in...

We derive an analytic model for nonlinear “photon bubble” wave trains driven by buoyancy forces in magnetized, radiation pressure-dominated atmospheres. Continuous, periodic wave solutions exist when radiative diffusion is slow compared to the dynamical timescale of the atmosphere. We identify these waves with the saturation of a linear instability discovered by Arons — therefore, these wave tr...

Title of Document: INTENSE LASER ACCELERATION OF QUASI-MONOENERGETIC PROTONS Tung-Chang Liu, Doctor of Philosophy, 2013 Directed By: Professor Chuan S Liu, Physics By irradiating an ultra-thin overdense foil with an intense circularly polarized laser beam, the laser radiation pressure can push the foil forward. This scheme, laser radiation pressure acceleration, is one of the most actively stud...

Outward radiation pressure can exceed the inward gravitational pull on gas clouds in the neighbourhood of a luminous Active Galactic Nucleus (AGN). This creates a forbidden region for long-lived dusty clouds in the observed columnn density – Eddington fraction plane. (The Eddington fraction λEdd is the ratio of the bolometric luminosity of an AGN to the Eddington limit for its black hole mass.)...

The distributions of L([O iii]λ5007), black hole (BH) mass and L/LEdd in two large samples of type-I and type-II active galactic nuclei (AGNs) are compared in order to test the suggestion that radiation pressure force is affecting the gas velocity in the broad line region and hence the BH mass determination. The samples are drawn from the SDSS archive and are modified to represent the same pare...

We consider the effects of “photon bubble” shock trains on the vertical structure of radiation pressure-dominated accretion disks. These density inhomogeneities are expected to develop spontaneously in radiation-dominated accretion disks where magnetic pressure exceeds gas pressure, even in the presence of magnetorotational instability (MRI). They increase the rate at which radiation escapes fr...