activity
20082022
most citedTesting General Relativity with stellar orbits around the supermassive black hole in our Galactic center

271 citations · 588 across the 12 of their papers we have counts for

collaborators

25 papers

astro-ph.IM20224 cited

AIROPA II: Modeling Instrumental Aberrations for Off-Axis Point Spread Functions in Adaptive Optics

Anna Ciurlo, Paolo Turri, Gunther Witzel +12

Images obtained with single-conjugate adaptive optics (AO) show spatial variation of the point spread function (PSF) due to both atmospheric anisoplanatism and instrumental aberrat…

astro-ph.IM20221 cited

AIROPA IV: Validating Point Spread Function Reconstruction on Various Science Cases

Sean K. Terry, Jessica R. Lu, Paolo Turri +7

We present an analysis of six independent on-sky datasets taken with the Keck-II/NIRC2 instrument. Using the off-axis point spread function (PSF) reconstruction software AIROPA, we…

astro-ph.HE202218 cited

Multi-wavelength Variability of Sagittarius A* in July 2019

H. Boyce, D. Haggard, G. Witzel +14

We report timing analysis of near-infrared (NIR), X-ray, and sub-millimeter (submm) data during a three-day coordinated campaign observing Sagittarius A*. Data were collected at 4.…

astro-ph.HE202164 cited

Constraining particle acceleration in Sgr A* with simultaneous GRAVITY, Spitzer, NuSTAR and Chandra observations

R. Abuter, A. Amorim, M. Bauböck +81

We report the time-resolved spectral analysis of a bright near-infrared and moderate X-ray flare of Sgr A*. We obtained light curves in the -, -, and -bands in the mid- an…

astro-ph.GA202126 cited

Second Scale Submillimeter Variability of Sagittarius A* during flaring activity of 2019: On the Origin of Bright Near Infrared Flares

Lena Murchikova, Gunther Witzel

In 2019, Sgr A* - the supermassive black hole in the Galactic Center - underwent unprecedented flaring activity in the near infrared (NIR), brightening by up to a factor of 100 com…

astro-ph.HE2020

Rapid Variability of Sgr A* across the Electromagnetic Spectrum

G. Witzel, G. Martinez, S. P. Willner +17

Sagittarius A* (Sgr A*) is the variable radio, near-infrared (NIR), and X-ray source associated with accretion onto the Galactic center black hole. We have analyzed a comprehensive…