The Square Kilometre Array (SKA): publications

Simultaneous optical and X-ray detection of a Thermonuclear Burst in the 2024 outburst of EXO 0748–676

Monthly Notices of the Royal Astronomical Society: Letters 91̽�� University Press (OUP) (2024) slae103

Authors:

Amy H Knight, Lauren Rhodes, Douglas JK Buisson, James H Matthews, Noel Castro Segura, Adam Ingram, Matthew Middleton, Timothy P Roberts

MIGHTEE: The Continuum Survey Data Release 1

(2024)

Authors:

CL Hale, I Heywood, MJ Jarvis, IH Whittam, PN Best, Fangxia An, RAA Bowler, I Harrison, A Matthews, DJB Smith, AR Taylor, M Vaccari

A hidden active galactic nucleus population: the first radio luminosity functions constructed by physical process

Monthly Notices of the Royal Astronomical Society: Letters 91̽�� University Press (OUP) 536:1 (2024) L32-L37

Authors:

Leah K Morabito, R Kondapally, PN Best, B-H Yue, JMGHJ de Jong, F Sweijen, Marco Bondi, Dominik J Schwarz, DJB Smith, RJ van Weeren, HJA Röttgering, TW Shimwell, Isabella Prandoni

Abstract:

ABSTRACT Both star formation (SF) and active galactic nuclei (AGNs) play an important role in galaxy evolution. Statistically quantifying their relative importance can be done using radio luminosity functions (RLFs). Until now these relied on galaxy classifications, where sources with a mixture of radio emission from SF and AGN are labelled as either a star-forming galaxy or an AGN. This can cause the misestimation of the relevance of AGN. Brightness temperature measurements at 144 MHz with the International LOw Frequency ARray telescope can separate radio emission from AGN and SF. We use the combination of sub-arcsec and arcsec resolution imaging of 7497 sources in the Lockman Hole and ELAIS-N1 fields to identify AGN components in the sub-arcsec resolution images and subtract them from the total flux density, leaving flux density from SF only. We construct, for the first time, RLFs by physical process, either SF or AGN activity, revealing a hidden AGN population at $L_{\textrm {144 MHz}}$$\lt 10^{24}$ W Hz$^{-1}$. This population is 1.56 $\pm$ 0.06 more than expected for $0.5\lt z\lt 2.0$ when comparing to RLFs by galaxy classification. The star-forming population has only 0.90 $\pm$ 0.02 of the expected SF. These ‘hidden’ AGNs can have significant implications for the cosmic SF rate and kinetic luminosity densities.

X-ray and Radio Campaign of the Z-source GX 340+0 II: the X-ray polarization in the normal branch

(2024)

Authors:

Yash Bhargava, Thomas D Russell, Mason Ng, Arvind Balasubramanian, Liang Zhang, Swati Ravi, Vishal Jadoliya, Sudip Bhattacharyya, Mayukh Pahari, Jeroen Homan, Herman L Marshall, Deepto Chakrabarty, Francesco Carotenuto, Aman Kaushik

Distance estimation of gamma-ray-emitting BL Lac objects from imaging observations

Astronomy & Astrophysics EDP Sciences 691 (2024) a154

Authors:

K Nilsson, V Fallah Ramazani, E Lindfors, P Goldoni, J Becerra González, JA Acosta Pulido, R Clavero, J Otero-Santos, T Pursimo, S Pita, PM Kouch, C Boisson, M Backes, G Cotter, F D’Ammando, E Kasai

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