Search Publications
Revisiting the multi-planetary system of the nearby star HD 20794: Confirmation of a low-mass planet in the habitable zone of a nearby G-dwarf
Bouchy, F.; Rebolo, R.; Quanz, S. P. +44 more
Context. Close-by Earth analogs and super-Earths are of primary importance because they will be preferential targets for the next generation of direct imaging instruments. Bright and close-by G-to-M type stars are preferential targets in radial velocity surveys to find Earth analogs. Their brightness allows us to achieve the best precision on RV m…
The role of the hot porous layer in the gas flow in the inner coma
Küppers, M.; Thomas, N.; Rezac, L. +5 more
Aims. The objective of this work is to study the influence of a highly non-isothermal porous dust layer on the formation of a comet's inner coma. We studied the water gas activity of comet 67P/Churyumov-Gerasimenko to find a link between the gas properties around the comet and the properties of the dust surface crust. The effects on the radiative …
Radial dependence of solar energetic particle peak fluxes and fluences: Multispacecraft observations based on Parker Solar Probe, Solar Orbiter, and near-Earth particle detectors
Guo, Jingnan; Wang, Yubao; Cao, Yihang
Context. We present a list of solar energetic particle (SEP) events detected by instruments on board the Solar and Heliospheric Observatory (SOHO), Parker Solar Probe (PSP), and Solar Orbiter between 2021 and 2023. The investigation focuses on identifying the peak flux and the fluence of SEP events in four energy ranges from 10.5 to 40 MeV, as obs…
Constraints on the X-ray-to-radio fluence ratio of FRB 20240114A
Kadler, M.; Eppel, F.; Krumpe, M. +8 more
We report on multiwavelength observations of FRB 20240114A, a nearby (z = 0.13), hyperactive, repeating fast radio burst that was discovered in January 2024. We performed simultaneous observations of the source with the Effelsberg 100-m radio telescope, the Thai National Radio Telescope, the Astropeiler Stockert, and the X-ray satellite XMM-Newton…
Transit-timing variations in the AU Mic system observed with CHEOPS
Guterman, P.; Alonso, R.; Deleuil, M. +86 more
Context. AU Mic is a very active M dwarf star with an edge-on debris disk and two known transiting sub-Neptunes with a possible third planetary companion. The two transiting planets exhibit significant transit-timing variations (TTVs) that are caused by the gravi tational interaction between the bodies in the system. Aims. Using photometrical obse…
Non-thermal emission in galaxy groups at extremely low frequency: The case of A1213
Gastaldello, F.; Santra, R.; Eckert, D. +7 more
Context. Galaxy clusters and groups are the last link in the chain of hierarchical structure formation. Their environments can be significantly affected by outbursts from active galactic nuclei (AGN), especially in groups where the medium density is lower and the gravitational potential is shallower. Thus, interaction between AGN and group weather…
MeerKAT discovery of gigahertz radio emission extending from Abell 3017 towards Abell 3016
Hu, Dan; Xu, Haiguang; Zhu, Zhenghao +18 more
Context. Cosmic filaments are vast, faint structures that connect galaxy clusters, often challenging to detect directly. However, filaments between pre-merger cluster pairs become more visible due to gas heating and compression while the clusters are approaching, enabling detection in X-ray and radio wavelengths. The clusters Abell 3017 and Abell …
LAMOST J171013+532646: A detached short-period noneclipsing hot subdwarf + white dwarf binary
Huang, Xin; Chen, Xuefei; Li, Zhenwei +9 more
We present an analysis of LAMOST J171013.211+532646.04 (hereafter J1710), a binary system comprising a hot subdwarf B star (sdB) and a white dwarf (WD) companion. Multi-epoch spectroscopy revealed an orbital period of 109.20279 minutes, consistent with TESS and ZTF photometric data. This means that this is the sixth detached system known to harbor…
Using Gaia and synthetic photometry for the absolute flux calibration of planetary cameras: The case of BepiColombo/SIMBIO-SYS
Cremonese, G.; Munaretto, G.; Sordo, R. +6 more
Context. The absolute flux calibration of a planetary camera is pivotal for a quantitative analysis of the brightness that is reflected by a celestial body to a) characterise its microphysical properties, b) analyse changes caused by exogenic or endogenic activity, and c) produce high-quality image mosaics to understand the geology of the body. Th…
Timing and spectral studies of the Be/X-ray binary EXO 2030+375 using Insight-HXMT observations
Bu, Qing-Cui; Santangelo, Andrea; Ji, Long +5 more
We report the results of a X-ray spectral and timing analysis of the high mass X-ray binary EXO 2030+375 during the 2021 type-II outburst based on Insight-HXMT observations. We confirm that pulsations can be detected in the energy band of 1‑150 keV. The pulse profile shows both energy and luminosity dependence and variability. We observed transiti…