collaborators

10 papers

astro-ph.GA2026

Discovery of a star sensitive to the spin of Sgr A*

K. Abd El Dayem, R. Abuter, N. Aimar +85

The paper reports the discovery of a faint main‑sequence star (S301) on an 8.7‑year, highly eccentric orbit around the Milky Way’s central black hole, whose high velocity makes its…

astro-ph.GA2026

Exploring the presence of a fifth force at the Galactic Center

The GRAVITY Collaboration, K. Abd El Dayem, R. Abuter +60

Aims: The presence of a Yukawa-like correction to Newtonian gravity is investigated at the Galactic Center, leading to a new upper limit for the intensity of such a correction. Met…

astro-ph.EP2026

The ExoGRAVITY survey: A K-band spectral library of giant exoplanet and brown dwarf companions

J. Kammerer, T. O. Winterhalder, S. Lacour +106

Direct observations of exoplanet and brown dwarf companions with near-infrared interferometry, first enabled by the dual-field mode of VLTI/GRAVITY, provide unique measurements of…

astro-ph.GA2025

Spatially resolved broad line region in a quasar at z=4: Dynamical black hole mass and prominent outflow

GRAVITY+ Collaboration, K. Abd El Dayem, N. Aimar +92

We present the first near-infrared interferometric data of a QSO at z=4. The K-band observations were performed with GRAVITY+ on the VLTI using all four UTs, detecting a differenti…

astro-ph.EP2025

Exomoon search with VLTI/GRAVITY around the substellar companion HD 206893 B

Q. Kral, J. Wang, J. Kammerer +130

Direct astrometric detection of exomoons remains unexplored. This study presents the first application of high-precision astrometry to search for exomoons around substellar compani…

astro-ph.EP2025

Constraints on the Orbit of the Young Substellar Companion GQ Lup B from High-Resolution Spectroscopy and VLTI/GRAVITY Astrometry

Vidya Venkatesan, S. Blunt, J. J. Wang +99

Understanding the orbits of giant planets is critical for testing planet formation models, particularly at wide separations greater than 10 au where traditional core accretion beco…