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Millihertz X-ray variability during the 2019 outburst of black hole candidate Swift J1357.2 − 0933

Monthly Notices of the Royal Astronomical Society 522:3 (2023) 4598-4611

Authors:

Aru Beri, Vishal Gaur, Phil Charles, David RA Williams, Jahanvi, John A Paice, Poshak Gandhi, Diego Altamirano, Rob Fender, David A Green, David Titterington
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Millihertz X-ray variability during the 2019 outburst of black hole candidate Swift~J1357.2$-$0933

(2023)

Authors:

Aru Beri, Vishal Gaur, Phil Charles, David RA Williams, Jahanvi, John A Paice, Poshak Gandhi, Diego Altamirano, Rob Fender, David A Green, David Titterington
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Key Science Goals for the Next-Generation Event Horizon Telescope

Galaxies MDPI 11:3 (2023) 61

Authors:

Michael D Johnson, Kazunori Akiyama, Lindy Blackburn, Katherine L Bouman, Avery E Broderick, Vitor Cardoso, Rob P Fender, Christian M Fromm, Peter Galison, José L Gómez, Daryl Haggard, Matthew L Lister, Andrei P Lobanov, Sera Markoff, Ramesh Narayan, Priyamvada Natarajan, Tiffany Nichols, Dominic W Pesce, Ziri Younsi, Andrew Chael, Koushik Chatterjee, Ryan Chaves, Juliusz Doboszewski, Richard Dodson, Sheperd S Doeleman, Jamee Elder, Garret Fitzpatrick, Kari Haworth, Janice Houston, Sara Issaoun, Yuri Y Kovalev, Aviad Levis, Rocco Lico, Alexandru Marcoci, Niels CM Martens, Neil M Nagar, Aaron Oppenheimer, Daniel CM Palumbo, Angelo Ricarte, María J Rioja, Freek Roelofs, Ann C Thresher, Paul Tiede, Jonathan Weintroub, Maciek Wielgus
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Constraints on axionlike particles from a combined analysis of three flaring Fermi flat-spectrum radio quasars

Physical Review D American Physical Society 107:8 (2023) 83027

Authors:

James Davies, Manuel Meyer, Garret Cotter

Abstract:

Many theories beyond the Standard Model of particle physics predict the existence of axionlike particles (ALPs) that mix with photons in the presence of a magnetic field. Searching for the effects of ALP-photon mixing in gamma-ray observations of blazars has provided some of the strongest constraints on ALP parameter space so far. Previously, only individual sources have been analyzed. We perform a combined analysis on Fermi Large Area Telescope data of three bright flaring flat-spectrum radio quasars, with the blazar jets themselves as the dominant mixing region. For the first time, we include a full treatment of photon-photon dispersion within the jet and account for the uncertainty in our B-field model by leaving the field strength free in the fitting. Overall, we find no evidence for ALPs but are able to exclude the ALP parameters 5 neV≲ma≲200 neV and gaγ≳5×10-12 GeV-1 with 95% confidence.
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Mass measurements and 3D orbital geometry of PSR J1933$-$6211

(2023)

Authors:

M Geyer, V Venkatraman Krishnan, PCC Freire, M Kramer, J Antoniadis, M Bailes, MCI Bernadich, S Buchner, AD Cameron, DJ Champion, A Karastergiou, MJ Keith, ME Lower, S Osłowski, A Possenti, A Parthasarathy, DJ Reardon, M Serylak, RM Shannon, R Spiewak, W van Straten, JPW Verbiest
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