Search Publications
Characterisation of the TOI-421 planetary system using CHEOPS, TESS, and archival radial velocity data
Alonso, R.; Deleuil, M.; Erikson, A. +88 more
Context. The TOI-421 planetary system contains two sub-Neptune-type planets (Pb ~ 5.2 days, Teq,b ~ 900 K, and Pc ~ 16.1 days, Teq,c ~ 650 K) and is a prime target to study the formation and evolution of planets and their atmospheres. The inner planet is especially interesting as the existence…
Running with the bulls: The frequency of star-disc encounters in the Taurus star-forming region
Benisty, Myriam; Joncour, Isabelle; Winter, Andrew J. +5 more
Context. Stars and planets form in regions of enhanced stellar density, subjecting protoplanetary discs to gravitational perturbations from neighbouring stars. Observations in the Taurus star-forming region have uncovered evidence of at least three recent, star-disc encounters that have truncated discs (HV/DO Tau, RW Aurigae, and UX Tau), raising …
Reassessing the proper motions of M31/M33 with Gaia DR3: Unravelling systematic uncertainties
Martin, Nicolas F.; Rusterucci, Samuel; Starkenburg, Else +1 more
We provide an updated inference of the proper motion of M31 using the Gaia DR3 proper motions of bright stars from the disc of M31. By refining the motion of the quasar reference frame, and statistically accounting for the variations in the inferred proper motions obtained across different regions of M31, we demonstrate that these inconsistencies …
PDRs4All. VII. The 3.3 µm aromatic infrared band as a tracer of physical properties of the interstellar medium in galaxies
Van De Putte, Dries; Lai, Thomas S. -Y.; Habart, Emilie +12 more
Aromatic infrared bands (AIBs) are a set of broad emission bands at 3.3, 6.2, 7.7, 8.6, 11.2, and 12.7 µm, seen in the infrared spectra of most galaxies. With the James Webb Space Telescope (JWST), the 3.3 µm AIB can in principle be detected up to a redshift of ~7. Relating the evolution of the 3.3 µm AIB to local physical proper…
Quasars as standard candles. V. Accounting for the dispersion in the LX-LUV relation down to ≤ 0.06 dex
Signorini, Matilde; Risaliti, Guido; Lusso, Elisabeta +4 more
A characteristic feature of quasars is the observed non-linear relationship between their monochromatic luminosities at rest-frame 2500 Å and 2 keV. This relationship is evident across all redshifts and luminosities and, due to its non-linearity, can be implemented to estimate quasar distances and construct a Hubble Diagram for quasars. Historical…
J0526+5934: A peculiar ultra-short-period double white dwarf
Rebassa-Mansergas, Alberto; Hollands, Mark; Parsons, Steven G. +6 more
Context. Ultra-short-period compact binaries are important sources of gravitational waves. The class of short-period compact binaries includes, for example, the progenitors of type Ia supernovae and the progenitors of merger episodes that may lead to massive and magnetic single white dwarfs. J0526+5934 is one such example: it is an unresolved comp…
INTEGRAL view of GRB 221009A. Prompt energetics and week-long hard X-ray afterglow
Mereghetti, Sandro; Tiengo, Andrea; Kuulkers, Erik +11 more
The gamma-ray burst GRB 221009A is among the most luminous of its kind and its proximity to Earth has made it an exceptionally rare observational event. The International Gamma-ray Astrophysics Laboratory (INTEGRAL) was in an optimal aspect position to use its all-sky instruments for recording the prompt emission and early gamma-ray afterglow in u…
Variation of the electron flux spectrum along a solar flare loop as inferred from STIX hard X-ray observations
Volpara, Anna; Massa, Paolo; Krucker, Säm +3 more
Context. Regularized imaging spectroscopy was introduced for the construction of electron flux images at different energies from count visibilities recorded by the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI). In this work we seek to extend this approach to data from the Spectrometer/Telescope for Imaging X-rays (STIX) on board th…
Three sub-Jovian-mass microlensing planets: MOA-2022-BLG-563Lb, KMT-2023-BLG-0469Lb, and KMT-2023-BLG-0735Lb
Han, Cheongho; Lee, Chung-Uk; Zang, Weicheng +45 more
Aims: We analyze the anomalies appearing in the light curves of the three microlensing events MOA-2022-BLG-563, KMT-2023-BLG-0469, and KMT-2023-BLG-0735. The anomalies exhibit common short-term dip features that appear near the peak.
Methods: From the detailed analyses of the light curves, we find that the anomalies were produced by plan…
The cosmic timeline implied by the JWST reionization crisis
Melia, F.
Context. JWST's discovery of well-formed galaxies and supermassive black holes only a few hundred million years after the big bang, and the identification of polycyclic aromatic hydrocarbons (PAHs) at z = 6.71, seriously challenge the timeline predicted by ΛCDM. Moreover, the implied bright UV-irradiation of the early Universe suggests a reionizat…