9 papers
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…
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…
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…
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…
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…
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…