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This paper defines the mathematical convention adopted to describe an electromagnetic wave and its polarisation state, as implemented in the PSRCHIVE software and represented in the PSRFITS definition. Contrast is made between the convention that has been widely accepted by pulsar astronomers and the IAU/IEEE definitions of the Stokes parameters. The former is adopted as the PSR/IEEE convention, and a set of useful parameters are presented for describing the differences between the PSR/IEEE standard and the conventions (either implicit or explicit) that form part of the design of observatory instrumentation. To aid in the empirical determination of instrumental convention parameters, well-calibrated average polarisation profiles of PSR J0304+1932 and PSR J0742-2822 are presented at radio wavelengths of approximately 10, 20, and 40 cm.
Since more than a century astronomers measure the position angle of the major axis of the polarization ellipse starting from the North direction and increasing counter-clockwise, when looking at the source. This convention has been enforced by the IA
When using valid foreground and signal models, the uncertainties on extracted signals in global 21-cm signal experiments depend principally on the overlap between signal and foreground models. In this paper, we investigate two strategies for decreasi
We present a pedagogical review of the weak gravitational lensing measurement process and its connection to major scientific questions such as dark matter and dark energy. Then we describe common ways of parametrizing systematic errors and understand
The Large Observatory for X-ray Timing (LOFT) is one of the five candidates that were considered by ESA as an M3 mission (with launch in 2022-2024). It is specifically designed to exploit the diagnostics of very rapid X-ray flux and spectral variabil
This paper defines the UK Infra-Red Telescope (UKIRT) Hemisphere Survey (UHS) and release of the remaining ~12,700 sq.deg of J-band survey data products. The UHS will provide continuous J and K-band coverage in the northern hemisphere from a declinat