72 citations · 253 across the 18 of their papers we have counts for
22 papers
A first look at the protoplanet WISPIT 2 b with VLTI/GRAVITY+
GRAVITY+ Collaboration, K. Abd El Dayem, R. Abuter +116
Confirmed observations of young protoplanets actively undergoing the process of formation have remained rare to date. In this Letter, we present new insights into the nature of the…
Searching for Nearby Supermassive Black Hole Binaries with GRAVITY
GRAVITY Collaboration, K. Abd El Dayem, N. Aimar +82
We present a systematic interferometric search for close supermassive black hole (SMBH) binaries in 20 nearby type 1 active galactic nuclei (AGN) observed with VLTI/\grav. We inves…
Improving constraints on the Yukawa correction at the Galactic Center with multiple stellar orbits
GRAVITY+ Collaboration, :, A. Foschi +78
We investigate the presence of a Yukawa-like correction () to Newtonian gravity at the Galactic Center, using a multi-star fitting code, including the newly…
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…
Using VLTI/GRAVITY+ to determine the identity of a third planet candidate in the PDS 70 system
David Trevascus, Wolfgang Brandner, Olga Balsalobre-Ruza +75
Detections of protoplanets are rare and protoplanetary disk features mischaracterized as planets are common. PDS 70 is one of only two stars known to host multiple confirmed protop…
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…
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…
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…
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…
First Resolution of Microlensed Images of a Binary-Lens Event
Zexuan Wu, Subo Dong, A. Mérand +72
We resolve the multiple images of the binary-lens microlensing event ASASSN-22av using the GRAVITY instrument of the Very Large Telescope Interferometer (VLTI). The light curves sh…
Observations of Microlensed Images with Dual-field Interferometry: On-sky Demonstration and Prospects
P. Mroz, S. Dong, A. Merand +57
Interferometric observations of gravitational microlensing events offer an opportunity for precise, efficient, and direct mass and distance measurements of lensing objects, especia…
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…
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…
X3: a high-mass Young Stellar Object close to the supermassive black hole Sgr~A*
Florian Peißker, Michal Zajacek, Nadeen B. Sabha +10
To date, the proposed observation of Young Stellar Objects (YSOs) in the Galactic center (GC) still raises the question where and how these objects could have formed due to the vio…
First observed interaction of the circumstellar envelope of an S-star with the environment of Sgr A*
Florian Peißker, Basel Ali, Michal Zajaček +7
Several publications highlight the importance of the observations of bow shocks to learn more about the surrounding interstellar medium and radiation field. We revisit the most pro…
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…
Kinematic Structure of the Galactic Center S-cluster
Basel Ali, Daria Paul, Andreas Eckart +7
We present a detailed analysis of the kinematics of 112 stars that mostly comprise the high velocity S-cluster and orbit the super massive black hole SgrA* at the center of the Mil…
Light and shadow in the Galactic Center - On the detection of the relativistic periastron shift of star S2 in the Galactic Center
A. Eckart, M. Parsa, E. Mossoux +11
We report on the nature of prominent sources of light and shadow in the Galactic Center. With respect to the Bremsstrahlung X-ray emission of the hot plasma in that region the Gala…
The Multifrequency Behavior of Sagittarius A*
A. Eckart, M. Zajacek, M. Parsa +15
The Galactic Center is the closest galactic nucleus that allows us to determine the multi-frequency behavior of the supermassive black hole counterpart Sagittarius A* in great deta…
Experimental Indicators of Accretion Processes in Active Galactic Nuclei
A. Eckart, M. Valencia-S., B. Shahzamanian +19
Bright Active Galactic Nuclei are powered by accretion of mass onto the super massive black holes at the centers of the host galaxies. For fainter objects star formation may signif…
Nuclear Activity and the Conditions of Star-formation at the Galactic Center
A. Eckart, M. Valencia-S., B. Shahzamanian +15
The Galactic Center is the closest galactic nucleus that can be studied with unprecedented angular resolution and sensitivity. We summarize recent basic observational results on Sa…
Nature of the Galactic centre NIR-excess sources. I. What can we learn from the continuum observations of the DSO/G2 source?
Michal Zajaček, Silke Britzen, Andreas Eckart +9
The Dusty S-cluster Object (DSO/G2) orbiting the supermassive black hole (Sgr A*) in the Galactic centre has been monitored in both near-infrared continuum and line emission. There…