activity
20182026
most citedDetection of the Schwarzschild precession in the orbit of the star S2 near the Galactic centre massive black hole

551 citations · 3.1k across the 55 of their papers we have counts for

collaborators

57 papers

astro-ph.IM2026

Bayesian Image Reconstruction with Spatially Variant PSFs in X-ray Astronomy

Vincent Eberle, Matteo Guardiani, Margret Westerkamp +4

X-ray observatories introduce unwanted instrumental effects into photon count data that must be accurately accounted for. In particular, the spatially variant point spread function…

astro-ph.GA2026★ 1 cited

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

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

Residing in the center of the Milky Way, Sgr A* is the closest massive black hole (MBH). Its vicinity has allowed measuring individual stellar orbits around it. The stars act as te…

astro-ph.EP2025★ 8 cited

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★ 6 cited

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.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…

astro-ph.IM2025★ 8 cited

First Light for the GRAVITY+ Adaptive Optics: Extreme Adaptive Optics for the Very Large Telescope Interferometer

GRAVITY+ Collaboration, :, F. Allouche +137

GRAVITY+ improves by orders of magnitude the sensitivity, sky-coverage and contrast of the Very Large Telescope Interferometer (VLTI). A central part of this project is the develop…

astro-ph.EP2025

Direct imaging discovery of a young giant planet orbiting on Solar System scales

T. Stolker, M. Samland, L. B. F. M. Waters +102

HD 135344 AB is a young visual binary system that is best known for the protoplanetary disk around the secondary star. The circumstellar environment of the A0-type primary star, on…

astro-ph.EP2025

Orbit and atmosphere of HIP 99770 b through the eyes of VLTI/GRAVITY

T. O. Winterhalder, J. Kammerer, S. Lacour +92

Context: Inferring the likely formation channel of giant exoplanets and brown dwarf companions from orbital and atmospheric observables remains a formidable challenge. Further and…

astro-ph.GA2024★ 48 cited

Improving constraints on the extended mass distribution in the Galactic Center with stellar orbits

The GRAVITY Collaboration, Karim Abd El Dayem, Roberto Abuter +66

Studying the orbital motion of stars around Sagittarius A* in the Galactic Center provides a unique opportunity to probe the gravitational potential near the supermassive black hol…

astro-ph.IM2024

High contrast at short separation with VLTI/GRAVITY: Bringing Gaia companions to light

N. Pourré, T. O. Winterhalder, J. -B. Le Bouquin +173

Since 2019, GRAVITY has provided direct observations of giant planets and brown dwarfs at separations of down to 95 mas from the host star. Some of these observations have provided…

astro-ph.EP2024

Astrometric detection of a Neptune-mass candidate planet in the nearest M-dwarf binary system GJ65 with VLTI/GRAVITY

GRAVITY Collaboration, R. Abuter, A. Amorim +65

The detection of low-mass planets orbiting the nearest stars is a central stake of exoplanetary science, as they can be directly characterized much more easily than their distant c…

astro-ph.EP2024★ 54 cited

Four-of-a-kind? Comprehensive atmospheric characterisation of the HR 8799 planets with VLTI/GRAVITY

E. Nasedkin, P. Mollière, S. Lacour +95

With four companions at separations from 16 to 71 au, HR 8799 is a unique target for direct imaging, presenting an opportunity for the comparative study of exoplanets with a shared…

astro-ph.EP2024★ 16 cited

Combining Gaia and GRAVITY: Characterising five new Directly Detected Substellar Companions

T. O. Winterhalder, S. Lacour, A. Mérand +96

Precise mass constraints are vital for the characterisation of brown dwarfs and exoplanets. Here we present how the combination of data obtained by Gaia and GRAVITY can help enlarg…

astro-ph.IM2024★ 10 cited

A catalogue of dual-field interferometric binary calibrators

M. Nowak, S. Lacour, R. Abuter +97

Dual-field interferometric observations with VLTI/GRAVITY sometimes require the use of a "binary calibrator", a binary star whose individual components remain unresolved by the int…

astro-ph.GA2023

Using the motion of S2 to constrain vector clouds around SgrA*

GRAVITY Collaboration, A. Foschi, R. Abuter +53

The dark compact object at the centre of the Milky Way is well established to be a supermassive black hole with mass , but the nature…

astro-ph.IM2023★ 1 cited

Polarization analysis of the VLTI and GRAVITY

GRAVITY Collaboration, F. Widmann, X. Haubois N. Schuhler +59

The goal of this work is to characterize the polarization effects of the VLTI and GRAVITY. This is needed to calibrate polarimetric observations with GRAVITY for instrumental effec…

astro-ph.GA2023★ 93 cited

Polarimetry and Astrometry of NIR Flares as Event Horizon Scale, Dynamical Probes for the Mass of Sgr A*

The GRAVITY Collaboration, R. Abuter, N. Aimar +66

We present new astrometric and polarimetric observations of flares from Sgr A* obtained with GRAVITY, the near-infrared interferometer at ESO's Very Large Telescope Interferometer…

astro-ph.HE2023★ 7 cited

First spatio-spectral Bayesian imaging of SN1006 in X-ray

Margret Westerkamp, Vincent Eberle, Matteo Guardiani +6

Supernovae are an important source of energy in the interstellar medium. Young remnants of supernovae have a peak emission in the X-ray region, making them interesting objects for…

astro-ph.GA2023★ 37 cited

Using the motion of S2 to constrain scalar clouds around SgrA*

GRAVITY Collaboration, A. Foschi, R. Abuter +67

The motion of S2, one of the stars closest to the Galactic Centre, has been measured accurately and used to study the compact object at the centre of the Milky Way. It is commonly…

astro-ph.CO2023★ 28 cited

Cosmology inference at the field level from biased tracers in redshift-space

Julia Stadler, Fabian Schmidt, Martin Reinecke

Cosmology inference of galaxy clustering at the field level with the EFT likelihood in principle allows for extracting all non-Gaussian information from quasi-linear scales, while…

astro-ph.GA2023★ 34 cited

Where intermediate-mass black holes could hide in the Galactic Centre: A full parameter study with the S2 orbit

The GRAVITY Collaboration, O. Straub, M. Bauböck +59

In the Milky Way the central massive black hole, SgrA*, coexists with a compact nuclear star cluster that contains a sub-parsec concentration of fast-moving young stars called S-st…

astro-ph.GA2023★ 3 cited

Accelerations of stars in central 2-7 arcsec from Sgr A*

A. Young, S. Gillessen, T. de Zeeuw +10

This work presents the results from extending the long-term monitoring program of stellar motions within the Galactic Center to include stars with separations of 2 - 7 arcseconds f…

astro-ph.IM2022★ 31 cited

First Light for GRAVITY Wide: Large Separation Fringe Tracking for the Very Large Telescope Interferometer

GRAVITY+ Collaboration, :, R. Abuter +114

GRAVITY+ is the upgrade of GRAVITY and the Very Large Telescope Interferometer (VLTI) with wide-separation fringe tracking, new adaptive optics, and laser guide stars on all four 8…

astro-ph.GA2022★ 69 cited

The young stars in the Galactic Center

Sebastiano von Fellenberg, Stefan Gillessen, Julia Stadler +11

We present a large spectroscopic survey of the Galactic Center using the SINFONI IFU at the VLT. Combining observations of the last two decades we compile s…