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Analysis of TID testing of a statistically large quantity of parts

Institute of Electrical and Electronics Engineers (IEEE) 00 (2021) 1-6

Authors:

Jorn Voegtli, Richard E Sharp, Lucy Oswald, Natalia Hong, Benjamin Archer

Two years of pulsar observations with the ultra-wide-band receiver on the Parkes radio telescope

Monthly Notices of the Royal Astronomical Society Oxford University Press 502:1 (2021) 1253-1262

Authors:

Simon Johnston, C Sobey, S Dai, M Keith, M Kerr, Rn Manchester, Ls Oswald, A Parthasarathy, Rm Shannon, P Weltevrede

Abstract:

The major programme for observing young, non-recycled pulsars with the Parkes telescope has transitioned from a narrow-band system to an ultra-wide-band system capable of observing between 704 and 4032 MHz. We report here on the initial 2 yr of observations with this receiver. Results include dispersion measure (DM) and Faraday rotation measure (RM) variability with time, determined with higher precision than hitherto, flux density measurements and the discovery of several nulling and mode changing pulsars. PSR J1703-4851 is shown to be one of a small subclass of pulsars that has a weak and a strong mode which alternate rapidly in time. PSR J1114-6100 has the fourth highest |RM| of any known pulsar despite its location far from the Galactic Centre. PSR J1825-1446 shows variations in both DM and RM likely due to its motion behind a foreground supernova remnant.

The Galactic center chimneys: The base of the multiphase outflow of the Milky Way

(2021)

Authors:

G Ponti, MR Morris, E Churazov, I Heywood, RP Fender

Radio flaring and dual radio loud/quiet behaviour in the new candidate black hole X-ray binary MAXI J1631-472

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 501:4 (2021) 5776-5781

Authors:

IM Monageng, SE Motta, R Fender, W Yu, PA Woudt, E Tremou, JCA Miller-Jones, AJ van der Horst

The rapid transition from star formation to AGN-dominated rest-frame ultraviolet light at z ≃ 4

Monthly Notices of the Royal Astronomical Society Oxford University Press 502:1 (2021) 662-677

Authors:

Raa Bowler, Nj Adams, Matthew Jarvis, B Häußler

Abstract:

With the advent of deep optical-to-near-infrared extragalactic imaging on the degree scale, samples of high-redshift sources are being selected that contain both bright star-forming (SF) galaxies and faint active galactic nuclei (AGN). In this study, we investigate the transition between SF- and AGN-dominated systems at z ≃ 4 in the rest-frame ultraviolet (UV). We find a rapid transition to AGN-dominated sources brightward of MUV ≃ −23.2. The effect is observed in the rest-frame UV morphology and size–luminosity relation, where extended clumpy systems become point-source-dominated, and also in the available spectra for the sample. These results allow us to derive the rest-frame UV luminosity function (LF) for the SF- and AGN-dominated subsamples. We find the SF-dominated LF is best fit with a double power law, with a lensed Schechter function being unable to explain the existence of extremely luminous SF galaxies at MUV ≃ −23.5. If we identify AGN-dominated sources according to a point-source morphology criterion, we recover the relatively flat faint-end slope of the AGN LF determined in previous studies. If we instead separate the LF according to the current spectroscopic AGN fraction, we find a steeper faint-end slope of α = −1.83 ± 0.11. Using a simple model to predict the rest-frame AGN LF from the z = 4 galaxy LF, we find that the increasing impact of host galaxy light on the measured morphology of faint AGN can explain our observations.