A spectroscopic, photometric, polarimetric, and radio study of the eclipsing polar UZ Fornacis: the first simultaneous SALT and MeerKAT observations

Monthly Notices of the Royal Astronomical Society Oxford University Press (OUP) 492:3 (2020) 4298-4312

Authors:

ZN Khangale, SB Potter, PA Woudt, DAH Buckley, AN Semena, EJ Kotze, DN Groenewald, DM Hewitt, ML Pretorius, RP Fender, P Groot, S Bloemen, M Klein-Wolt, E Körding, R Le Poole, VA McBride, L Townsend, K Paterson, DLA Pieterse, P Vreeswijk

Detection of very-high-energy γ-ray emission from the colliding wind binary η Car with H.E.S.S.

Astronomy & Astrophysics EDP Sciences 635 (2020) a167

Authors:

H Abdalla, R Adam, F Aharonian, F Ait Benkhali, EO Angüner, M Arakawa, C Arcaro, C Armand, T Armstrong, H Ashkar, M Backes, V Barbosa Martins, M Barnard, Y Becherini, D Berge, K Bernlöhr, R Blackwell, M Böttcher, C Boisson, J Bolmont, S Bonnefoy, J Bregeon, M Breuhaus, F Brun, P Brun, M Bryan, M Büchele, T Bulik, T Bylund, S Caroff, A Carosi, S Casanova, M Cerruti, T Chand, S Chandra, A Chen, S Colafrancesco, G Cotter, M Curyło, ID Davids, J Davies, C Deil, J Devin, P deWilt, L Dirson, A Djannati-Ataï, A Dmytriiev, A Donath, V Doroshenko, J Dyks, K Egberts, F Eichhorn, G Emery, J-P Ernenwein, S Eschbach, K Feijen, S Fegan, A Fiasson, G Fontaine, S Funk, M Füßling, S Gabici, YA Gallant, F Gaté, G Giavitto, L Giunti, D Glawion, JF Glicenstein, D Gottschall, M-H Grondin, J Hahn, M Haupt, G Heinzelmann, G Henri, G Hermann, JA Hinton, W Hofmann, C Hoischen, TL Holch, M Holler, M Hörbe, D Horns, D Huber, H Iwasaki, M Jamrozy, D Jankowsky, F Jankowsky, A Jardin-Blicq, V Joshi, I Jung-Richardt, MA Kastendieck, K Katarzyński, M Katsuragawa, U Katz, D Khangulyan, B Khélifi, J King, S Klepser, W Kluźniak, Nu Komin, K Kosack, D Kostunin, M Kreter, G Lamanna, A Lemière, M Lemoine-Goumard, J-P Lenain, E Leser, C Levy, T Lohse, I Lypova, J Mackey, J Majumdar, D Malyshev, D Malyshev, V Marandon, P Marchegiani, A Marcowith, A Mares, G Martí-Devesa, R Marx, G Maurin, PJ Meintjes, R Moderski, M Mohamed, L Mohrmann, C Moore, P Morris, E Moulin, J Muller, T Murach, S Nakashima, K Nakashima, M de Naurois, H Ndiyavala, F Niederwanger, J Niemiec, L Oakes, P O’Brien, H Odaka, S Ohm, E de Ona Wilhelmi, M Ostrowski, M Panter, RD Parsons, C Perennes, P-O Petrucci, B Peyaud, Q Piel, S Pita, V Poireau, A Priyana Noel, DA Prokhorov, H Prokoph, G Pühlhofer, M Punch, A Quirrenbach, S Raab, R Rauth, A Reimer, O Reimer, Q Remy, M Renaud, F Rieger, L Rinchiuso, C Romoli, G Rowell, B Rudak, E Ruiz-Velasco, V Sahakian, S Sailer, S Saito, DA Sanchez, A Santangelo, M Sasaki, M Scalici, R Schlickeiser, F Schüssler, A Schulz, HM Schutte, U Schwanke, S Schwemmer, M Seglar-Arroyo, M Senniappan, AS Seyffert, N Shafi, K Shiningayamwe, R Simoni, A Sinha, H Sol, A Specovius, S Spencer, M Spir-Jacob, � Stawarz, R Steenkamp, C Stegmann, C Steppa, T Takahashi, T Tavernier, AM Taylor, R Terrier, D Tiziani, M Tluczykont, L Tomankova, C Trichard, M Tsirou, N Tsuji, R Tuffs, Y Uchiyama, DJ van der Walt, C van Eldik, C van Rensburg, B van Soelen, G Vasileiadis, J Veh, C Venter, P Vincent, J Vink, HJ Völk, T Vuillaume, Z Wadiasingh, SJ Wagner, J Watson, F Werner, R White, A Wierzcholska, R Yang, H Yoneda, M Zacharias, R Zanin, AA Zdziarski, A Zech, J Zorn, N Żywucka

The rise and fall of an extraordinary Ca-rich transient

Astronomy & Astrophysics EDP Sciences 635 (2020) a186

Authors:

SJ Prentice, K Maguire, A Flörs, S Taubenberger, C Inserra, C Frohmaier, TW Chen, JP Anderson, C Ashall, P Clark, M Fraser, L Galbany, A Gal-Yam, M Gromadzki, CP Gutiérrez, PA James, PG Jonker, E Kankare, G Leloudas, MR Magee, PA Mazzali, M Nicholl, M Pursiainen, K Skillen, SJ Smartt, KW Smith, C Vogl, DR Young

LSQ13ddu: a rapidly evolving stripped-envelope supernova with early circumstellar interaction signatures

Monthly Notices of the Royal Astronomical Society Oxford University Press (OUP) 492:2 (2020) 2208-2228

Authors:

Peter Clark, Kate Maguire, Cosimo Inserra, Simon Prentice, Stephen J Smartt, Carlos Contreras, Griffin Hossenizadeh, Eric Y Hsiao, Erkki Kankare, Mansi Kasliwal, Peter Nugent, Melissa Shahbandeh, Charles Baltay, David Rabinowitz, Iair Arcavi, Chris Ashall, Christopher R Burns, Emma Callis, Ting-Wan Chen, Tiara Diamond, Morgan Fraser, D Andrew Howell, Emir Karamehmetoglu, Rubina Kotak, Joseph Lyman, Nidia Morrell, Mark Phillips, Giuliano Pignata, Miika Pursiainen, Jesper Sollerman, Maximilian Stritzinger, Mark Sullivan, David Young

GW170817A as a Hierarchical Black Hole Merger

ASTROPHYSICAL JOURNAL LETTERS American Astronomical Society 890:2 (2020) ARTN L20

Authors:

V Gayathri, I Bartos, Z Haiman, S Klimenko, B Kocsis, S Marka, Y Yang

Abstract:

Despite the rapidly growing number of stellar-mass binary black hole mergers discovered through gravitational waves, the origin of these binaries is still not known. In galactic centers, black holes can be brought to each others' proximity by dynamical processes, resulting in mergers. It is also possible that black holes formed in previous mergers encounter new black holes, resulting in so-called hierarchical mergers. Hierarchical events carry signatures such as higher-than usual black hole mass and spin. Here we show that the recently reported gravitational-wave candidate, GW170817A, could be the result of such a hierarchical merger. In particular, its chirp mass $\sim40$ M$_\odot$ and effective spin of $\chi_{\rm eff}\sim0.5$ are the typically expected values from hierarchical mergers within the disks of active galactic nuclei. We find that the reconstructed parameters of GW170817A strongly favor a hierarchical merger origin over having been produced by an isolated binary origin (with an Odds ratio of $>10^3$, after accounting for differences between the expected rates of hierarchical versus isolated mergers)