Rubin-LSST

Research group

Research theme

Sub department

About

A Challenge to the Standard Cosmological Model

The Astrophysical Journal Letters American Astronomical Society 937:2 (2022) L31-L31

Authors:

Nathan J Secrest, Sebastian von Hausegger, Mohamed Rameez, Roya Mohayaee, Subir Sarkar

Finding high-redshift gamma-ray bursts in tandem near-infrared and optical surveys

Nature Astronomy 6:10 (2022) 1101-1104

Authors:

S Campana, G Ghirlanda, R Salvaterra, OA Gonzalez, M Landoni, G Pariani, A Riva, M Riva, SJ Smartt, NR Tanvir, SD Vergani

Panic! at the Disks: First Rest-frame Optical Observations of Galaxy Structure at z > 3 with JWST in the SMACS 0723 Field

ASTROPHYSICAL JOURNAL LETTERS 938:1 (2022) ARTN L2

Authors:

Leonardo Ferreira, Nathan Adams, Christopher J Conselice, Elizaveta Sazonova, Duncan Austin, Joseph Caruana, Fabricio Ferrari, Aprajita Verma, James Trussler, Tom Broadhurst, Jose Diego, Brenda L Frye, Massimo Pascale, Stephen M Wilkins, Rogier A Windhorst, Adi Zitrin

Collaborative experience between scientific software projects using Agile Scrum development

Software Practice and Experience Wiley 52:10 (2022) 2077-2096

Authors:

Amanda L Baxter, Segev Y BenZvi, Walter Bonivento, Adam Brazier, Michael Clark, Alexis Coleiro, David Collom, Marta Colomer‐Molla, Bryce Cousins, Aliwen Delgado Orellana, Damien Dornic, Vladislav Ekimtcov, Shereen ElSayed, Andrea Gallo Rosso, Patrick Godwin, Spencer Griswold, Alec Habig, Remington Hill, Shunsaku Horiuchi, D Andrew Howell, Margaret WG Johnson, Mario Jurić, James P Kneller, Abigail Kopec, Claudio Kopper, Vladimir Kulikovskiy, Mathieu Lamoureux, Rafael F Lang, Shengchao Li, Massimiliano Lincetto, Lindy Lindstrom, Mark W Linvill, Curtis McCully, Jost Migenda, Danny Milisavljevic, Spencer Nelson, Rita Novoseltseva, Erin O'Sullivan, Donald Petravick, Barry W Pointon, Nirmal Raj, Andrew Renshaw, Janet Rumleskie, Tom Sonley, Ron Tapia, Jeffrey CL Tseng, Christopher D Tunnell, Godefroy Vannoye, Carlo F Vigorito, Clarence J Virtue, Christopher Weaver, Kathryn E Weil, Lindley Winslow, Rich Wolski, Xun‐Jie Xu, Yiyang Xu, The SCiMMA and SNEWS Collaborations

Radio observations of the Black Hole X-ray Binary EXO 1846-031 re-awakening from a 34-year slumber

Monthly Notices of the Royal Astronomical Society Oxford University Press 517:2 (2022) 2801-2817

Authors:

Dra Williams, Se Motta, R Fender, Jca Miller-Jones, J Neilsen, Jr Allison, J Bright, I Heywood, Pfl Jacob, L Rhodes, E Tremou, Pa Woudt, J van den Eijnden, F Carotenuto, Da Green, D Titterington, Aj van der Horst, P Saikia

Abstract:

We present radio [1.3 GHz MeerKAT, 4–8 GHz Karl G. Jansky Very Large Array (VLA), and 15.5 GHz Arcminute Microkelvin Imager Large Array (AMI-LA)] and X-ray (Swift and MAXI) data from the 2019 outburst of the candidate Black Hole X-ray Binary (BHXB) EXO 1846−031. We compute a Hardness–Intensity diagram, which shows the characteristic q-shaped hysteresis of BHXBs in outburst. EXO 1846−031 was monitored weekly with MeerKAT and approximately daily with AMI-LA. The VLA observations provide sub-arcsecond-resolution images at key points in the outburst, showing moving radio components. The radio and X-ray light curves broadly follow each other, showing a peak on ∼MJD 58702, followed by a short decline before a second peak between ∼MJD 58731–58739. We estimate the minimum energy of these radio flares from equipartition, calculating values of Emin ∼ 4 × 1041 and 5 × 1042 erg, respectively. The exact date of the return to ‘quiescence’ is missed in the X-ray and radio observations, but we suggest that it likely occurred between MJD 58887 and 58905. From the Swift X-ray flux on MJD 58905 and assuming the soft-to-hard transition happened at 0.3–3 per cent Eddington, we calculate a distance range of 2.4–7.5 kpc. We computed the radio:X-ray plane for EXO 1846−031 in the ‘hard’ state, showing that it is most likely a ‘radio-quiet’ BH, preferentially at 4.5 kpc. Using this distance and a jet inclination angle of θ = 73◦, the VLA data place limits on the intrinsic jet speed of βint = 0.29c, indicating subluminal jet motion.