One of the tenets of the radio pulsar observational picture is that the integrated pulse profiles are constant with time. This assumption underpins much of the fantastic science made possible via pulsar timing. Over the past few years, however, this assumption has come under question with a number of pulsars showing pulse shape changes on a range of timescales. Here, we show the dramatic appear...

There are concerns that radically new fiber designs and network architectures will soon be required in order to keep up with exponential growth of internet traffic in the backbone network in a cost effective manner [1]. Spatial division multiplexing (SDM) schemes employing either multi core fibers (MCFs) or multi-mode fibers (MMFs) have been recently proposed and successfully demonstrated [2,3]...

The charge profile of thermally poled electrets has been studied using two different methods, laser induced pressure pulse (LIPP) and pulsed electroacoustic (PEA), to gain insight into the mechanisms that are activated and assess which is the most appropriate method to study the charge profile. Disc–shaped PET samples have been conventionally poled to activate both the α and the ρ relaxation an...

We have studied the effective response of composites of spherical particles with a dielectric profile which varies along the radius of the particles. We developed a differential effective dipole theory to compute the dipole moment of individual spherical particle and hence the effective dielectric response of a dilute suspension. The theory has been applied to two model dielectric profiles. Mor...

A femtosecond X-ray source was developed by Thomson scattering through interaction between a lowemittance picosecond electron beam and a terawatt femtosecond laser light at 90 configuration. The observed X-ray intensity with peak energy of 2.3 keV and pulse duration of 270 fs rms was typically 1.4x10 photons/pulse. The pulse-to-pulse fluctuation of the X-ray intensity was measured to be 25%. Th...

[1] A vector radiative transfer model was used in conjunction with the line-by-line radiative transfer model and the database of high-resolution transmission (HITRAN) molecular absorption to simulate the degree of linear polarization of skylight in cloud-free conditions. Differences between simulated and measured polarization data in highspectral resolution are found to be within 1% after aeros...

We present new calculations of X-ray polarization from black hole (BH) accretion disks in the thermally-dominated state, using a Monte-Carlo ray-tracing code in full general relativity. In contrast to many previously published studies, our approach allows us to include returning radiation that is deflected by the strong-field gravity of the BH and scatters off of the disk before reaching a dist...

We describe a low-pressure flow-through apparatus for generating hyperpolarized Xe and report its performance by examining both the output Xe polarization PXe by NMR and the in situ Rb polarization profile by optically detected electron paramagnetic resonance. The polarizer is based on a previously presented design employing a long optical pumping cell, lean Xe mixture at low pressure, Rb presa...