Vertaisarvioitu alkuperäisartikkeli tai data-artikkeli tieteellisessä aikakauslehdessä (A1)

Characterizing and Mitigating Intraday Variability: Reconstructing Source Structure in Accreting Black Holes with mm-VLBI




Julkaisun tekijät: Broderick AE, Gold R, Georgiev B, Pesce DW, Tiede P, Ni CC, Moriyama K, Akiyama K, Alberdi A, Alef W, Algaba JC, Anantua R, Asada K, Azulay R, Bach U, Baczko AK, Ball D, Balokovic M, Barrett J, Baubock M, Benson BA, Bintley D, Blackburn L, Blundell R, Bouman KL, Bower GC, Boyce H, Bremer M, Brinkerink CD, Brissenden R, Britzen S, Broguiere D, Bronzwaer T, Bustamante S, Byun DY, Carlstrom JE, Ceccobello C, Chael A, Chan CK, Chatterjee K, Chatterjee S, Chen MT, Chen YJ, Cheng XP, Cho I, Christian P, Conroy NS, Conway JE, Cordes JM, Crawford TM, Crew GB, Cruz-Osorio A, Cui YZ, Davelaar J, De Laurentis M, Deane R, Dempsey J, Desvignes G, Dexter J, Dhruv V, Doeleman SS, Dougal S, Dzib SA, Eatough RP, Emami R, Falcke H, Farah J, Fish VL, Fomalont E, Ford HA, Fraga-Encinas R, Freeman WT, Friberg P, Fromm CM, Fuentes A, Galison P, Gammie CF, Garcia R, Gentaz O, Goddi C, Gomez-Ruiz AI, Gomez JL, Gu MF, Gurwell M, Hada K, Haggard D, Haworth K, Hecht MH, Hesper R, Heumann D, Ho LC, Ho P, Honma M, Huang CWL, Huang L, Hughes DH, Ikeda S, Impellizzeri CMV, Inoue M, Issaoun S, James DJ, Jannuzi BT, Janssen M, Jeter B, Jiang W, Jimenez-Rosales A, Johnson MD, Jorstad S, Joshi AV, Jung T, Karami M, Karuppusamy R, Kawashima T, Keating GK, Kettenis M, Kim DJ, Kim JY, Kim J, Kim J, Kino M, Koay JY, Kocherlakota P, Kofuji Y, Koch PM, Koyama S, Kramer C, Kramer M, Krichbaum TP, Kuo CY, La Bella N, Lauer TR, Lee D, Lee SS, Leung PK, Levis A, Li ZY, Lico R, Lindahl G, Lindqvist M, Lisakov M, Liu J, Liu K, Liuzzo E, Lo WP, Lobanov AP, Loinard L, Lonsdale CJ, Lu RS, Mao JR, Marchili N, Markoff S, Marrone DP, Marscher AP, Marti-Vidal I, Matsushita S, Matthews LD, Menten KM, Michalik D, Mizuno I, Mizuno Y, Moran JM, Moscibrodzka M, Muller C, Mus A, Musoke G, Myserlis I, Nadolski A, Nagai H, Nagar NM, Nakamura M, Narayan R, Narayanan G, Natarajan I, Nathanail A, Fuentes SN, Neilsen J, Neri R, Noutsos A, Nowak MA, Oh J, Okino H, Olivares H, Ortiz-Leon GN, Oyama T, Palumbo DCM, Paraschos GF, Park J, Parsons H, Patel N, Pen UL, Pietu V, Plambeck R, PopStefanija A, Porth O, Potzl FM, Prather B, Preciado-Lopez JA, Pu HY, Ramakrishnan V, Rao R, Rawlings MG, Raymond AW, Rezzolla L, Ricarte A, Ripperda B, Roelofs F, Rogers A, Ros E, Romero-Canizales C, Roshanineshat A, Rottmann H, Roy AL, Ruiz I, Ruszczyk C, Rygl KLJ, Sanchez S, Sanchez-Arguelles D, Sanchez-Portal M, Sasada M, Satapathy K, Savolainen T, Schloerb FP, Schonfeld J, Schuster KF, Shao LJ, Shen ZQ, Small D, Sohn BW, SooHoo J, Souccar K, Sun H, Tazaki F, Tetarenko AJ, Tilanus RPJ, Titus M, Torne P, Traianou E, Trent T, Trippe S, Turk M, van Bemmel I, van Langevelde HJ, van Rossum DR, Vos J, Wagner J, Ward-Thompson D, Wardle J, Weintroub J, Wex N, Wharton R, Wielgus M, Wiik K, Witzel G, Wondrak MF, Wong GN, Wu QW, Yamaguchi P, Yoon D, Young A, Young K, Younsi Z, Yuan F, Yuan YF, Zensus JA, Zhao GY, Zhang S, Zhao SS

Kustantaja: IOP Publishing Ltd

Julkaisuvuosi: 2022

Journal: Astrophysical Journal Letters

Tietokannassa oleva lehden nimi: ASTROPHYSICAL JOURNAL LETTERS

Lehden akronyymi: ASTROPHYS J LETT

Volyymi: 930

Julkaisunumero: 2

Sivujen määrä: 30

ISSN: 2041-8205

eISSN: 2041-8213

DOI: http://dx.doi.org/10.3847/2041-8213/ac6584

Verkko-osoite: https://doi.org/10.3847/2041-8213/ac6584

Rinnakkaistallenteen osoite: https://research.utu.fi/converis/portal/detail/Publication/175665774


Tiivistelmä

The extraordinary physical resolution afforded by the Event Horizon Telescope has opened a window onto the astrophysical phenomena unfolding on horizon scales in two known black holes, M87* and Sgr A*. However, with this leap in resolution has come a new set of practical complications. Sgr A* exhibits intraday variability that violates the assumptions underlying Earth aperture synthesis, limiting traditional image reconstruction methods to short timescales and data sets with very sparse (u, v) coverage. We present a new set of tools to detect and mitigate this variability. We develop a data-driven, model-agnostic procedure to detect and characterize the spatial structure of intraday variability. This method is calibrated against a large set of mock data sets, producing an empirical estimator of the spatial power spectrum of the brightness fluctuations. We present a novel Bayesian noise modeling algorithm that simultaneously reconstructs an average image and statistical measure of the fluctuations about it using a parameterized form for the excess variance in the complex visibilities not otherwise explained by the statistical errors. These methods are validated using a variety of simulated data, including general relativistic magnetohydrodynamic simulations appropriate for Sgr A* and M87*. We find that the reconstructed source structure and variability are robust to changes in the underlying image model. We apply these methods to the 2017 EHT observations of M87*, finding evidence for variability across the EHT observing campaign. The variability mitigation strategies presented are widely applicable to very long baseline interferometry observations of variable sources generally, for which they provide a data-informed averaging procedure and natural characterization of inter-epoch image consistency.


Ladattava julkaisu

This is an electronic reprint of the original article.
This reprint may differ from the original in pagination and typographic detail. Please cite the original version.




Last updated on 2022-08-08 at 07:56