papers

Publications (36)

astro-ph.EP2024

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.SR2022

The GRAVITY Young Stellar Object survey -- IX. Spatially resolved kinematics of hot hydrogen gas in the star/disk interaction region of T Tauri stars

GRAVITY Collaboration, J. A. Wojtczak, L. Labadie +58

Aims: We aim to spatially and spectrally resolve the Br-gamma hydrogen emission line with the methods of interferometry in order to examine the kinematics of the hydrogen gas emiss…

astro-ph.SR2023

VLTI/GRAVITY Observations and Characterization of the Brown Dwarf Companion HD 72946 B

W. O. Balmer, L. Pueyo, T. Stolker +96

Tension remains between the observed and modeled properties of substellar objects, but objects in binary orbits, with known dynamical masses can provide a way forward. HD 72946 B i…

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.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.GA2021

Deep Images of the Galactic Center with GRAVITY

GRAVITY Collaboration, R. Abuter, N. Aimar +65

Stellar orbits at the Galactic Center provide a very clean probe of the gravitational potential of the supermassive black hole. They can be studied with unique precision, beyond th…

astro-ph.GA2026

S301 and friends: Measuring the spin of Sgr A*

T. Piran, P. Amaro-Seoane, B. Aytac +15

The discovery of S301 (GRAVITY Collaboration et al., 2026) with pericenter distance rp= 280rg and eccentricity e=0.9825, opens the prospect of measuring the spin parameter of Sgr A…

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…

#galactic center#black hole spin#stellar orbits#relativistic dynamics
astro-ph.GA2023

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.GA2024

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.EP2023

Direct discovery of the inner exoplanet in the HD206893 system. Evidence for deuterium burning in a planetary-mass companion

S. Hinkley, S. Lacour, G. -D. Marleau +110

Long term precise radial velocity (RV) monitoring of the nearby star HD206893, as well as anomalies in the system proper motion, have suggested the presence of an additional, inner…

astro-ph.IM2024

Upgrading the GRAVITY fringe tracker for GRAVITY+: Tracking the white light fringe in the non-observable Optical Path Length state-space

M. Nowak, S. Lacour, R. Abuter +35

Aims. As part of the ongoing GRAVITY+ upgrade of the Very Large Telescope Interferometer infrastructure, we aim to improve the performance of the GRAVITY Fringe-Tracker, and to ena…

astro-ph.SR2024

The GRAVITY young stellar object survey XIV : Investigating the magnetospheric accretion-ejection processes in S CrA N

GRAVITY Collaboration, H. Nowacki, K. Perraut +53

The dust- and gas-rich protoplanetary disks around young stellar systems play a key role in star and planet formation. While considerable progress has recently been made in probing…

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.IM2024

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.SR2024

The cool brown dwarf Gliese 229 B is a close binary

Jerry W. Xuan, A. Mérand, W. Thompson +76

Owing to their similarities with giant exoplanets, brown dwarf companions of stars provide insights into the fundamental processes of planet formation and evolution. From their orb…

astro-ph.SR2024

The GRAVITY young stellar object survey XIII. Tracing the time-variable asymmetric disk structure in the inner AU of the Herbig star HD98922

GRAVITY Collaboration, V. Ganci, L. Labadie +52

Temporal variability in the photometric and spectroscopic properties of protoplanetary disks is common in YSO. However, evidence pointing toward changes in their morphology over sh…

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

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.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.SR2023

VLTI/GRAVITY Provides Evidence the Young, Substellar Companion HD 136164 Ab formed like a "Failed Star"

William O. Balmer, L. Pueyo, S. Lacour +93

Young, low-mass Brown Dwarfs orbiting early-type stars, with low mass ratios (), appear intrinsically rare and present a formation dilemma: could a handful of these…

astro-ph.EP2023

First VLTI/GRAVITY Observations of HIP 65426 b: Evidence for a Low or Moderate Orbital Eccentricity

S. Blunt, W. O. Balmer, J. J. Wang +95

Giant exoplanets have been directly imaged over orders of magnitude of orbital separations, prompting theoretical and observational investigations of their formation pathways. In t…

astro-ph.SR2026

The GRAVITY young stellar object survey -- XV. The star-disk interaction region of the T Tauri star DO Tau

GRAVITY Collaboration, K. Perraut, J. Bouvier +61

Protoplanetary disks around young Sun-like stars are the cradles of the vast majority of detected exoplanets. Probing these disks at multiple spatial scales is key to uncovering ho…

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.SR2024

The GRAVITY young stellar object survey XII. The hot gas disk component in Herbig Ae/Be stars

GRAVITY Collaboration, R. Garcia Lopez, A. Natta +46

The region of protoplanetary disks closest to a star (within 1-2\,au) is shaped by a number of different processes, from accretion of the disk material onto the central star to eje…

astro-ph.GA2025

The gas streamer G1-2-3 in the Galactic Center

S. Gillessen, F. Eisenhauer, J. Cuadra +61

The black hole in the Galactic Center, Sgr A*, is prototypical for ultra-low-fed galactic nuclei. The discovery of a hand-full of gas clumps in the realm of a few Earth masses in i…

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…

quant-ph2006

Alternative scheme for two-qubit conditional phase gate by adiabatic passage under dissipation

Z. J. Deng, K. L. Gao, F. Mang

We check a recent proposal [H. Goto and K. Ichimura Phys. Rev. A 70, 012305 (2004)] for controlled phase gate through adiabatic passage under the influence of spontaneous emission…

astro-ph.EP2023

The GRAVITY young stellar object survey: XI. Imaging the hot gas emission around the Herbig Ae star HD 58647

Y. -I. Bouarour, R. Garcia Lopez, J. Sanchez-Bermudez +45

We aim to investigate the origin of the HI Br emission in young stars by using GRAVITY to image the innermost region of circumstellar disks, where important physical processes…

astro-ph.GA2024

A dynamical measure of the black hole mass in a quasar 11 billion years ago

R. Abuter, F. Allouche, A. Amorim +124

Tight relationships exist in the local universe between the central stellar properties of galaxies and the mass of their supermassive black hole. These suggest galaxies and black h…

astro-ph.EP2024

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.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.IM2023

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

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.IM2025

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.IM2022

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…