Accurate atomic models for astrophysical plasma can be very complex, requiring thousands of states. However, for a variety of applications such as large-scale forward models of the Stokes parameters of a spectral line in the solar corona, it is necessary to build much reduced atomic models. We present two examples of such models, focused on the two

This work focuses on the study of the anomalous microwave emission (AME), an important emission mechanism between 10 and 60 GHz whose polarisation properties are not yet fully understood and is therefore a potential contaminant for future cosmic microwave background (CMB) polarisation observations. We used new QUIJOTE-MFI maps at 11, 13, 17, and 19

The large abundance of electrically neutral particles has a remarkable impact on the dynamics of many astrophysical plasmas. Here, we use a two-fluid model that includes charge-neutral elastic collisions and Hall's current to study the propagation of magnetohydrodynamic (MHD) waves in weakly ionized plasmas. We derive the dispersion relation for

We present the analysis of optical/near-infrared (NIR) data and host galaxy properties of a bright, extremely rapidly evolving transient, AT 2024wpp, which resembles the enigmatic AT 2018cow. AT 2024wpp rose to a peak brightness of $c=-21.9$ mag in 4.3 d and remained above the half-maximum brightness for only 6.7 d. The blackbody fits to the

We present results from a high-cadence multiwavelength observational campaign of the enigmatic changing-look active galactic nucleus 1ES 1927+654 from 2022 May to 2024 April, coincident with an unprecedented radio flare (an increase in flux by a factor of ∼60 over a few months) and the emergence of a spatially resolved jet at 0.1–0.3 pc scales

We present multiwavelength analysis of ZTF23abelseb (AT 2023sva), an optically discovered fast-fading ( $\Delta m_r = 2.2$ mag in $\Delta t = 0.74$ d), luminous ( $M_r \sim -30.0$ mag), and red ( $g-r = 0.50$ mag) transient at $z = 2.28$ with accompanying luminous radio emission. AT 2023sva does not possess a $\gamma$-ray burst (GRB) counterpart to