The Square Kilometre Array (SKA)

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Subgalactic Scaling Relations with T e-based Metallicities of Low-metallicity Regions in Galaxies: Metal-poor Gas Inflow May Have Important Effects?

The Astrophysical Journal American Astronomical Society 926:1 (2022) 57

Authors:

Yao Yao, Haiyang Liu, Xu Kong, Yulong Gao, Guangwen Chen, Xinkai Chen, Zhixiong Liang, Zesen Lin, Yimeng Tang, Hong-Xin Zhang
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The 1.28 GHz MeerKAT Galactic Center Mosaic

The Astrophysical Journal American Astronomical Society 925:2 (2022) 165

Authors:

I Heywood, I Rammala, F Camilo, WD Cotton, F Yusef-Zadeh, TD Abbott, RM Adam, G Adams, MA Aldera, KMB Asad, EF Bauermeister, TGH Bennett, HL Bester, WA Bode, DH Botha, AG Botha, LRS Brederode, S Buchner, JP Burger, T Cheetham, DIL de Villiers, MA Dikgale-Mahlakoana, LJ du Toit, SWP Esterhuyse, BL Fanaroff, S February, DJ Fourie, BS Frank, RRG Gamatham, M Geyer, S Goedhart, M Gouws, SC Gumede, MJ Hlakola, A Hokwana, SW Hoosen, JMG Horrell, B Hugo, AI Isaacson, GIG Józsa, JL Jonas, AF Joubert, RPM Julie, FB Kapp, JS Kenyon, PPA Kotzé, N Kriek, H Kriel, VK Krishnan, R Lehmensiek, D Liebenberg, RT Lord, BM Lunsky, K Madisa, LG Magnus, O Mahgoub, A Makhaba, S Makhathini, JA Malan, JR Manley, SJ Marais, A Martens, T Mauch, BC Merry, RP Millenaar, N Mnyandu, OJ Mokone, TE Monama, MC Mphego, WS New, B Ngcebetsha, KJ Ngoasheng, MT Ockards, N Oozeer, AJ Otto, SS Passmoor, AA Patel, A Peens-Hough, SJ Perkins, AJT Ramaila, NMR Ramanujam, ZR Ramudzuli, SM Ratcliffe, A Robyntjies, S Salie, N Sambu, CTG Schollar, LC Schwardt, RL Schwartz, M Serylak, R Siebrits, SK Sirothia, M Slabber, OM Smirnov, L Sofeya, B Taljaard, C Tasse, AJ Tiplady, O Toruvanda, SN Twum, TJ van Balla, A van der Byl, C van der Merwe, V Van Tonder, R Van Wyk, AJ Venter, M Venter, BH Wallace, MG Welz, LP Williams, B Xaia
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Toward an X-ray inventory of nearby neutron stars

Astronomy & Astrophysics EDP Sciences 658 (2022) a95

Authors:

A Vahdat, B Posselt, A Santangelo, GG Pavlov
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A Late-Time Radio Flare following a Possible Transition in Accretion State in the Tidal Disruption Event AT 2019azh

(2022)

Authors:

I Sfaradi, A Horesh, R Fender, DA Green, DRA Williams, J Bright, S Schulze
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Relevance of photon-photon dispersion within the jet for blazar axionlike particle searches

Physical Review D American Physical Society 105:2 (2022) 23017

Authors:

James Davies, Garret Cotter, Manuel Meyer

Abstract:

Axionlike particles (ALPs) could mix with photons in the presence of astrophysical magnetic fields. Searching for this effect in gamma-ray observations of blazars has provided some of the strongest constraints on ALP parameter space so far. Previously, photon-photon dispersion of gamma rays off of the cosmic microwave background has been shown to be important for these calculations and is universally included in ALP-photon mixing models. Here, we assess the effects of dispersion off of other photon fields within the blazar (produced by the accretion disk, the broad line region, the dust torus, starlight, and the synchrotron field) by modeling the jet and fields of the flat spectrum radio quasar 3C454.3 and propagating ALPs through the model both with and without the full dispersion calculation. We find that the full dispersion calculation can strongly affect the mixing, particularly at energies above 100 GeV—often reducing the ALP-photon conversion probability. This could have implications for future searches planned with, e.g., the Cherenkov Telescope Array, particularly those looking for a reduced opacity of the Universe at the highest energies.
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