activity
20122026
most citedThe X-ray Flux Distribution of Sagittarius A* as Seen by Chandra

63 citations · 224 across the 33 of their papers we have counts for

collaborators

35 papers

astro-ph.IM2026

NASA ASTRA White Paper : A Chandra Successor in the 2030s

C. S. Reynolds, E. Hodges-Kluck, E. A. Kara +19

Chandra established that soft X-ray spectral imaging with approximately 1 arcsec angular resolution is an essential tool for almost every area of astrophysics, from the early Unive…

astro-ph.HE2026

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…

astro-ph.HE2026

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…

astro-ph.GA2026

Dynamics and geometry of the inner sub-parsec-scale jet in 3C 279 observed with the Event Horizon Telescope

Hendrik Mueller, Sebastiano D. von Fellenberg, Ai-Ling Zeng +275

The 2021 Event Horizon Telescope observations resolve the innermost jet region of the blazar 3C279 with unprecedented detail. The reconstructed images consistently reveal a compact…

astro-ph.HE2026

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…

astro-ph.HE2026

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…

astro-ph.GA2026

Ionization Structure and Metal Enrichment of the Galactic Center Minispiral Observed with JWST

Nicole M Ford, Mayura Balakrishnan, Sebastiano D. von Fellenberg +11

Sagittarius A* (Sgr A*) is the nearest quiescent supermassive black hole, and its proximity offers a unique opportunity to study its surrounding fuel supply. We leverage extensive…

astro-ph.HE2026

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…

astro-ph.GA2026

Full-polarization millimeter wavelength variability of Sagittarius A* during the 2018 EHT campaign

Ezequiel Albentosa-Ruiz, Jasmin E. Washington, Nicola Marchili +272

Sagittarius A* (Srg A*), the supermassive black hole at the center of the Milky Way, provides a unique laboratory to study accretion dynamics and plasma processes near the event ho…

astro-ph.HE2026

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…

astro-ph.IM2026

Probabilistic Interpolation of Sagittarius A*'s Multi-Wavelength Light Curves Using Diffusion Models

Gabriel Sasseville, Julie Hlavacek-Larrondo, Daryl Haggard +3

Understanding the variability of Sagittarius A* (Sgr A*) requires coordinated, multi-wavelength observations that span the electromagnetic spectrum. In this work, we focus on data…

astro-ph.GA2026

Hubble Study of the Proper Motion of HST-1 in the Jet of M87

Rameshan Thimmappa, Joey Neilsen, Daryl Haggard +2

The radio galaxy M87 is well known for its jet, which features a series of bright knots observable from radio to X-ray wavelengths. The most famous of these, HST-1, exhibits superl…

astro-ph.HE2026★ 1 cited

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…

astro-ph.HE2026★ 1 cited

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…

astro-ph.HE2025★ 4 cited

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…

astro-ph.GA2025★ 1 cited

Photometric Constraints on Intermediate-mass Black Holes in the Galactic Centre

Tamojeet Roychowdhury, Sebastiano D. von Fellenberg, Joseph M. Michail +14

JWST/MIRI observations can place photometric limits on the presence of an intermediate-mass black hole (IMBH) near the Galactic Centre. The stellar complex IRS 13E, a co-moving con…

astro-ph.HE2025

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…

astro-ph.HE2025★ 3 cited

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…

astro-ph.HE2025

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…

astro-ph.HE2025

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…

astro-ph.HE2025

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…

astro-ph.HE2025★ 4 cited

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…

astro-ph.GA2025★ 8 cited

First polarization study of the M87 jet and active galactic nuclei at submillimeter wavelengths with ALMA

Ciriaco Goddi, Douglas F. Carlos

We present full-polarization observations at mm (345 GHz) conducted with the Atacama Large Millimeter/submillimeter Array (ALMA) toward Messier 87 (M87) and seven other r…

astro-ph.IM2025

GWSkyNet-Multi II: an updated machine learning model for rapid classification of gravitational-wave events

Nayyer Raza, Man Leong Chan, Daryl Haggard +5

Multi-messenger observations of gravitational waves and electromagnetic emission from compact object mergers offer unique insights into the structure of neutron stars, the formatio…