63 citations · 224 across the 33 of their papers we have counts for
26 papers · 1 filter
Advancing Fundamental Physics and Cosmology with high-resolution X-ray imaging
Sara Turriziani, Herman L. Marshall, Daryl Haggard +4
Black Holes are the key to solving many unanswered questions in fundamental physics: in particular, the very extreme properties shown by supermassive black holes at the centers of…
The second Arcminute Microkelvin Imager - Large Array Gamma-ray burst radio afterglow catalog
L. Rhodes, D. Ibrahim, N. Sqalli +13
Radio observations of gamma-ray burst afterglows provide insight in to the different emitting regions within the jet, its hydrodynamics and burst environment. In this paper, we pre…
Broadband multiwavelength properties of the archetypal blazar 3C 279 during the 2017 Event Horizon Telescope campaign
G. Principe, J. C. Algaba, E. Aviano +529
The archetypal blazar 3C 279 hosts a prominent relativistic jet and exhibits strong broadband variability across the electromagnetic spectrum. In April 2017, the Event Horizon Tele…
The Demographics of Sagittarius A* X-ray Flares over 25 Years with Chandra
Zach Sumners, Nicole M. Ford, Daryl Haggard +10
We present the Chandra 25-year Sagittarius A* (Sgr A*) X-ray flare catalog: a systematic analysis of 6.8 Ms of Sgr A* monitoring spanning the Chandra X-ray Observatory's mission li…
Infrared Line Diagnostics Fail to Constrain Sgr A*'s UV Output
Mayura Balakrishnan, Sebastiano D. von Fellenberg, Daryl Haggard +11
Sgr A*, the 4 x supermassive black hole at the Galactic Center, exhibits frequent flaring with X-ray luminosities of erg s, while i…
Detection and Evolution of Linear Polarization of the Galactic Center Transient MAXI J1744-294
Joseph M. Michail, Sebastiano D. von Fellenberg, Mayura Balakrishnan +14
MAXI J1744294, likely a low-mass X-ray binary system, is a Galactic-center transient source, detected at radio and X-ray wavelengths, located approximately southeast of S…
Locating the missing large-scale emission in the jet of M87* with short EHT baselines
Boris Georgiev, Paul Tiede, Sebastiano D. von Fellenberg +280
In Very-Long Baseline Interferometric arrays, nearly co-located stations probe the largest scales and typically cannot resolve the observed source. In the absence of large-scale st…
Ring Asymmetry and Spin in M87*
Vadim Bernshteyn, Nicholas S. Conroy, Michi Bauböck +263
Event Horizon Telescope (EHT) images of the supermassive black hole M87* depict an asymmetric ring of emission. General relativistic magnetohydrodynamic (GRMHD) models of M87* and…
Probing jet base emission of M87* with the 2021 Event Horizon Telescope observations
Saurabh, Hendrik Müller, Sebastiano D. von Fellenberg +282
We investigate the presence and spatial characteristics of the jet base emission in M87* at 230 GHz, enabled by the enhanced uv coverage in the 2021 Event Horizon Telescope (EHT) o…
First Mid-infrared Detection and Modeling of a Flare from Sgr A*. II. Mid-IR Spectral Energy Distribution and Millimeter Polarimetry
Joseph M. Michail, Sebastiano D. von Fellenberg, Garrett K. Keating +20
S. D. von Fellenberg et al. (2025a, Paper I) reported the first mid-infrared detection of a flare from Sgr A*. The JWST/MIRI/MRS observations were consistent with an orbiting hotsp…
The Advanced X-ray Imaging Satellite (AXIS) Community Science Book
Michael Koss, Nafisa Aftab, Steven W. Allen +395
The AXIS Community Science Book represents the collective effort of 592 scientists worldwide to define the transformative science enabled by the Advanced X-ray Imaging Satellite (A…
Fast X-ray Transient Detection with AXIS: application to Magnetar Giant Flares
Michela Negro, Zorawar Wadiasingh, George Younes +6
Magnetar giant flares (MGFs) are among the most luminous high-energy transients in the local universe, consisting of a short, intense MeV gamma-ray spike followed by a softer, puls…
A multiwavelength study of the Galactic center black hole candidate MAXI J1744-294
Shifra Mandel, Kaya Mori, Paul A. Draghis +37
For the first time in nearly a decade, a bright transient was detected in the central parsec (pc) of the Galaxy. MAXI J1744-294, or -- as it was known in its previous life -- Swift…
Thermal electrons in the radio afterglow of relativistic tidal disruption event ZTF22aaajecp/AT2022cmc
Lauren Rhodes, Ben Margalit, Joe S. Bright +11
A tidal disruption event (TDE) occurs when a star travels too close to a supermassive black hole. In some cases, accretion of the disrupted material onto the black hole launches a…
Origin of the ring ellipticity in the black hole images of M87*
Rohan Dahale, Ilje Cho, Kotaro Moriyama +273
We investigate the origin of the elliptical ring structure observed in the images of the supermassive black hole M87*, aiming to disentangle contributions from gravitational, astro…
Spectral Insights and Evolutionary Pathways of Globular Cluster ULX in NGC 1399: A Two-Decade X-ray and Optical Study
Kwangmin Oh, Kristen C. Dage, Alexey Bobrick +9
We present new multi-wavelength observations of two ultraluminous X-ray sources (ULXs) hosted by globular clusters (GCs) in the giant elliptical NGC 1399, focusing on CXO J0338318-…
First mid-infrared detection and modeling of a flare from Sgr A*
Sebastiano D. von Fellenberg, Tamojeet Roychowdhury, Joseph M. Michail +24
The time-variable emission from the accretion flow of Sgr A*, the supermassive black hole at the Galactic Center, has long been examined in the radio-to-mm, near-infrared (NIR), an…
A multi-frequency study of sub-parsec jets with the Event Horizon Telescope
Jan Röder, Maciek Wielgus, Andrei P. Lobanov +287
The 2017 observing campaign of the Event Horizon Telescope (EHT) delivered the first very long baseline interferometry (VLBI) images at the observing frequency of 230 GHz, leading…
Tracking X-ray Variability in Next Generation EHT LLAGN Targets
Nicole M. Ford, Michael Nowak, Venkatessh Ramakrishnan +4
We present a 5 month NICER X-ray monitoring campaign for two low luminosity active galactic nuclei (LLAGNs) -- NGC 4594 and IC 1459 -- with complementary Swift and NuSTAR observati…
Monitoring Observations of SMC X-1's Excursions (MOOSE) III: X-ray Spectroscopy of a Warped, Precessing Accretion Disc
Rawan Karam, Kristen C. Dage, Bailey E. Tetarenko +11
The MOOSE (Monitoring Observations of SMC X-1 Excursions) program uses the Neutron Star Interior Composition Explorer Mission (NICER) to monitor the high mass X-ray binary SMC X-1…
Multistructured accretion flow of Sgr A* I: Examination of a RIAF model
Mayura Balakrishnan, Lia Corrales, Sera Markoff +8
The extreme low-luminosity supermassive black hole Sgr A* provides a unique laboratory in which to test radiatively inefficient accretion flow (RIAF) models. Previous fits to the q…
Simulation-based inference of radio millisecond pulsars in globular clusters
Joanna Berteaud, Christopher Eckner, Francesca Calore +2
Millisecond pulsars (MSPs) are abundant in globular clusters (GCs), which offer favorable environments for their creation. While the advent of recent, powerful facilities led to a…
Simultaneous X-ray and Infrared Observations of Sagittarius A*'s Variability
H. Boyce, D. Haggard, G. Witzel +11
Emission from Sgr A* is highly variable at both X-ray and infrared (IR) wavelengths. Observations over the last ~20 years have revealed X-ray flares that rise above a quiescent the…
Simultaneous Multi-band Radio & X-ray Observations of the Galactic Center Magnetar SGR 17452900
T. T. Pennucci, A. Possenti, P. Esposito +7
We report on multi-frequency, wideband radio observations of the Galactic Center magnetar (SGR 17452900) with the Green Bank Telescope for 100 days immediately following i…