We report on the detection of X-ray polarisation in the black-hole X-ray binary Swift J1727.8−1613 during its dim hard spectral state by the Imaging X-ray Polarimetry Explorer (IXPE). This is the first detection of X-ray polarisation at the transition from the soft to the hard state in an X-ray binary. We find an averaged 2-8 keV polarisation

Context. Advancements in instrumentation have revealed a multitude of small-scale extreme-ultraviolet (EUV) events in the solar atmosphere and considerable effort is currently undergoing to unravel them. Aims: Our aim is to employ high-resolution and high-sensitivity magnetograms to gain a detailed understanding of the magnetic origin of such

Context. The physical parameters of the sunspot are not fully understood, especially the height dependence of the magnetic field. So far, it is also an open question as to which heights the He I 10 830 Å spectral line is formed at. Aims: Our aim is to investigate the magnetic and dynamical properties in the atmosphere above a sunspot, from the

We studied the effects of cluster environments on galactic structures by using the TNG50 cosmological simulation and observed galaxies in the Fornax cluster. We focused on galaxies with stellar masses of 10 8 − 12 M ⊙ at z = 0 that reside in Fornax-like clusters with total masses of M 200c = 10 13.4 − 14.3 M ⊙. We characterized the stellar

Aims: Our science goals are to characterise the optical properties of Y dwarfs and to study their consistency with theoretical models. Methods: A sample of five Y dwarfs was observed with three optical and near-infrared instruments at the 10.4m Gran Telescopio Canarias. Deep near-infrared (J- or H-band) and multicolour optical images (z-, i-, r-, G

Galaxy clusters at low redshift are dominated by massive quiescent galaxies hosting stellar populations 10 Gyrs old, indicating that they were formed in the early universe when clusters were still in the process of being assembled (i.e., protoclusters). The rapid growth of galaxies within protoclusters is driven by the efficient transformation of