Search Publications
MINDS: The DR Tau disk. I. Combining JWST-MIRI data with high-resolution CO spectra to characterise the hot gas
Henning, Thomas; Waters, L. B. F. M.; Güdel, Manuel +29 more
Context. The MRS mode of the JWST-MIRI instrument has been shown to be a powerful tool to characterise the molecular gas emission of the inner region of planet-forming disks. Investigating their spectra allows us to infer the composition of the gas in these regions and, subsequently, the potential atmospheric composition of the forming planets. We…
Fast-rotating massive Population III stars as possible sources of extreme N enrichment in high-redshift galaxies
Sibony, Yves; Nandal, Devesh; Tsiatsiou, Sophie
We present an analysis of the chemical compositions in high-redshift galaxies, with a focus on the nitrogen-enhanced galaxies GN-z11 and CEERS-1019. We used stellar models of massive stars with initial masses ranging from 9 to 120 M⊙ and various metallicities to deduce the chemical abundances of stellar ejecta for a few light elements (…
JWST observations of 13CO2 ice. Tracing the chemical environment and thermal history of ices in protostellar envelopes
Manoj, P.; Narang, Mayank; Bourke, Tyler L. +38 more
The structure and composition of simple ices can be severely modified during stellar evolution by protostellar heating. Key to understanding the involved processes are thermal and chemical tracers that can be used to diagnose the history and environment of the ice. The 15.2 µm bending mode of 12CO2 in particular has proven to…
The COSMOS-Web ring: In-depth characterization of an Einstein ring lensing system at z ∼ 2
Sanders, D. B.; Ilbert, O.; Kartaltepe, J. S. +35 more
Aims: We provide an in-depth analysis of the COSMOS-Web ring, an Einstein ring at z ≈ 2 that we serendipitously discovered during the data reduction of the COSMOS-Web survey and that could be the most distant lens discovered to date.
Methods: We extracted the visible and near-infrared photometry of the source and the lens from more than …
IXPE observation confirms a high spin in the accreting black hole 4U 1957+115
Antonelli, L. A.; Costa, E.; Bianchi, S. +113 more
We present the results of the first X-ray polarimetric observation of the low-mass X-ray binary 4U 1957+115, performed with the Imaging X-ray Polarimetry Explorer in May 2023. The binary system has been in a high-soft spectral state since its discovery and is thought to host a black hole. The ∼571 ks observation reveals a linear polarisation degre…
X-Shooting ULLYSES: Massive stars at low metallicity: VIII. Stellar and wind parameters of newly revealed stripped stars in Be binaries
Wang, L.; Hamann, W. -R.; Oey, M. S. +16 more
On the route toward merging neutron stars and stripped-envelope supernovae, binary population synthesis predicts a large number of post-interaction systems with massive stars that have been stripped of their outer layers. However, observations of such stars in the intermediate-mass regime below the Wolf-Rayet masses are rare. Using X-Shooting ULLY…
Discovery of a strong rotation of the X-ray polarization angle in the galactic burster GX 13+1
Done, Chris; Kaaret, Philip; Wu, Kinwah +106 more
Weakly magnetized neutron stars in X-ray binaries show a complex phenomenology with several spectral components that can be associated with the accretion disk, the boundary, and/or a spreading layer, a corona, and a wind. Spectroscopic information alone, however, is not enough to distinguish these components. The analysis of the timing data reveal…
2D disc modelling of the JWST line spectrum of EX Lupi
Woitke, P.; Kamp, I.; Ábrahám, P. +3 more
We introduce a number of improvements to the thermo-chemical disc modelling code PRODIMO and new theoretical approaches that can be used to better predict and analyse the JWST line spectra of protoplanetary discs. We developed a new line escape probability method for disc geometries, and a new scheme for dust settling, and discuss how to apply UV …
AGNs in massive galaxy clusters: Role of galaxy merging, infalling groups, cluster mass, and dynamical state
Koulouridis, E.; Drigga, E.; Gkini, A.
Context. There is compelling evidence that active galactic nuclei (AGNs) in high-density regions have undergone a different evolution than their counterparts in the field, indicating that they are strongly affected by their environment. However, we still lack a comprehensive understanding of the dominant mechanisms that trigger the nucleus and the…
Anatomy of an ionized bubble: NIRCam grism spectroscopy of the z = 6.6 double-peaked Lyman-α emitter COLA1 and its environment
Conroy, Charlie; Sobral, David; Tacchella, Sandro +10 more
The increasingly neutral intergalactic gas at z > 6 impacts the Lyman-α (Lyα) flux observed from galaxies. One luminous galaxy, COLA1, stands out because of its unique double-peaked Lyα line at z = 6.6, unseen in any simulation of reionization. Here, we present JWST/NIRCam wide-field slitless spectroscopy in a 21 arcmin2 field center…