Recently, Photonic Slot Routing (PSR) has been proposed as a practical solution for achieving optically transparent communication in Wavelength Division Multiplexing (WDM) wide-area networks. PSR makes use of available and simple wavelength-non-sensitive optical devices to switch data ows at di erent wavelengths, but in the same time slot, as a single unit. It thereby trades switching node comp...

The binaries PSR J1141–6545 and PSR B2303+46 each appear to contain a white dwarf which formed before the neutron star. We describe an evolutionary pathway to produce these two systems. In this scenario, the primary transfers its envelope onto the secondary which is then the more massive of the two stars, and indeed sufficiently massive later to produce a neutron star via a supernova. The core ...

Biological attack of pyrite is a potential method of reducing pyritic sulphur in coal. Integration of such attacks with microwave pretreatment can enhance the efficiency of the process. Alternatively, processes such as oil-agglomeration can be coupled with the biological attack to obtain higher rates of pyritic sulphur removal. In this study desulphurization of Indian (Assam) coal was carried o...

We have conducted timing observations of the eclipsing millisecond binary pulsar PSR B1957+20, extending the span of data on this pulsar to more than five years. During this time the orbital period of the system has varied by roughly ∆Pb/Pb = 1.6 × 10, changing quadratically with time and displaying an orbital period second derivative P̈b = (1.43±0.08)×10 −18 s. The previous measurement of a lar...

In this paper we report unusual glitches in two young pulsars, PSR J1825−0935 (B1822−09) and PSR J1835−1106. For PSR J1825−0935, a slow glitch characterised by a temporary decrease in the slowdown rate occurred between 2000 December 31 to 2001 December 6. This event resulted in a permanent increase in frequency with fractional size ∆ν/ν ∼ 31.2(2)×10, however little effect remained in slowdown r...

We report on high-speed optical photometry of the radio positions of two young rotation-powered pulsars. No pulsations were detected from the optical counterpart proposed by Caraveo et al. (1994) for PSR B1509–58, with a 2σ upper limit on the pulsed fraction of < 12%, significantly lower than that measured in the five known optical pulsars. Given its low pulsed fraction, high optical luminosity...

Using archival Chandra data we studied the X-ray emission properties of PSR B2224+65 and its environment. Albeit limited by photon statistics the spectral analysis suggests that the bulk of the emission from PSR B2224+65 is non-thermal. Fitting a power-law to the observed energy spectrum yields a photon index of Γ = 1.58 +0.43 −0.33. The possible origin of the non-thermal pulsar emission is dis...

The observed braking index nobs which had been determined for a few young pulsars, had been found to differ from the expected value for a rotating magnetic dipole model. In addition, the observational jerk parameter, determined for two of these pulsars, disagrees with the theoretical prediction mobs = 15 in both cases. We propose a simple model able to account for these differences, based on a ...

We report the X-ray observations of two radio pulsars with drifting subpulses, B0834+06 and B0826 34, using XMM-Newton. PSR B0834+06 was detected with a total of 70 counts from the three EPIC instruments over 50 ks exposure time. Its spectrum is best described as that of a blackbody (BB), with temperature Ts 1⁄4 (2:0þ2:0 0:9) ; 10 K and bolometric luminosity Lb 1⁄4 (8:6þ14:2 4:4 ) ; 10 erg s . ...

We have obtained an HI absorption spectrum of the relativistic binary PSR J1141−6545 and used it to constrain the distance to the system. The spectrum suggests that the pulsar is at, or beyond, the tangent point, estimated to be at 3.7 kpc. PSR J1141−6545 offers the promise of stringent tests of General Relativity (GR) by comparing its observed orbital period derivative with that derived from o...