Search Publications
Hydrodynamic simulation of Cygnus OB2: the absence of a cluster wind termination shock
Sander, A. A. C.; Ramachandran, V.; Larkin, C. J. K. +3 more
We perform a large-scale hydrodynamic simulation of a massive star cluster whose stellar population mimics that of the Cygnus OB2 association. The main-sequence stars are first simulated during 1.6 Myr, until a quasi-stationary state is reached. At this time, the three Wolf-Rayet stars observed in Cygnus OB2 are added to the simulation, which cont…
Precise characterisation of HD 15337 with CHEOPS: A laboratory for planet formation and evolution
Guterman, P.; Alonso, R.; Deleuil, M. +90 more
Context. The HD 15337 (TIC 120896927, TOI-402) system was observed by the Transiting Exoplanet Survey Satellite (TESS), revealing the presence of two short-period planets situated on opposite sides of the radius gap. This offers an excellent opportunity to study theories of formation and evolution, as well as to investigate internal composition an…
Post-new-horizons Orbits and Masses for the Satellites of Pluto
Jacobson, Robert A.; Brozović, Marina
We report on ephemerides for the satellites of Pluto based on the large set of astrometric measurements. Our orbit fit yielded the following masses with 1σ uncertainties: GM Pluto = 869.3 ± 0.4 km3 s‑2, GM Charon = 106.1 ± 0.3 km3 s‑2, GM Nix = 1.50 ± 0.52 × 10‑3
Dependence of Virial Factors on Optical Spectral Properties of Active Galactic Nuclei
Du, Pu; Wang, Jian-Min; Yang, Sen
Reverberation mapping (RM) has long been a powerful tool for measuring the masses of supermassive black holes (SMBHs) at the centers of active galactic nuclei (AGNs), but the precision of these mass measurements depends on the so-called virial factors. It has been demonstrated that the virial factors exhibit significant diversity, spanning approxi…
The Companion Mass Distribution of Post Common Envelope Hot Subdwarf Binaries: Evidence for Boosted and Disrupted Magnetic Braking?
El-Badry, Kareem; Nagarajan, Pranav; van Roestel, Jan +6 more
We measure the mass distribution of main-sequence (MS) companions to hot subdwarf B stars (sdBs) in post-common envelope binaries (PCEBs). We carried out a spectroscopic survey of 14 eclipsing systems ("HW Vir binaries") with orbital periods of 3.8 < Porb < 12 hr, resulting in a well-understood selection function and a near-comple…
Stellar angular momentum of intermediate-redshift galaxies in MUSE surveys
Krajnović, D.; Contini, T.; Pessa, I. +8 more
We quantify the stellar rotation of galaxies by computing the λR parameter, a proxy for the stellar angular momentum in a sample of 106 intermediate-redshift galaxies (0.1 < z < 0.8). The sample is located in the CANDELS/GOODS-S and CANDELS/COSMOS regions, and it was observed by various MUSE surveys. We created spatially resolved …
Spectroscopic triples and a chance alignment: a solution for the problem of suspicious mass ratios for SB2s from Wilson method
Han, Zhanwen; Kovalev, Mikhail; Chen, Xuefei
We selected three double-lined spectroscopic binary systems which have extreme mass ratios, if measured using the Wilson method. We analysed medium resolution spectroscopic observations and space-based photometry and find that all these systems are not SB2, but rather triple systems and a chance alignment of another star with SB1 that have an unse…
Disentangling the X-ray variability in the Lyman continuum emitter Haro 11
Östlin, G.; Herenz, E. C.; Silich, S. +1 more
Context. Lyman break analogs in the local Universe serve as counterparts to Lyman break galaxies (LBGs) at high redshifts, which are widely regarded as major contributors to cosmic reionization in the early stages of the Universe. Aims. We studied XMM-Newton and Chandra observations of the nearby LBG analog Haro 11, which contains two X-ray-bright…
CURLING - I. The influence of point-like image approximation on the outcomes of cluster strong lens modelling
Li, Jiadong; Kneib, Jean-Paul; Acebron, Ana +11 more
Cluster-scale strong lensing is a powerful tool for exploring the properties of dark matter and constraining cosmological models. However, due to the complex parameter space, pixelized strong lens modelling in galaxy clusters is computationally expensive, leading to the point-source approximation of strongly lensed extended images, potentially int…
The MUSE eXtremely Deep Field: Detections of circumgalactic Si II* emission at z ≳ 2
Ouchi, Masami; Blaizot, Jérémy; Garel, Thibault +17 more
Context. The circumgalactic medium (CGM) serves as a baryon reservoir that connects galaxies to the intergalactic medium and fuels star formation. The spatial distribution of the metal-enriched cool CGM has not yet been directly revealed at cosmic noon (z ≃ 2–4), as bright emission lines at these redshifts are not covered by optical integral field…