Report on the activities carried out in WP3

G. Viavattene (1), I. Ermolli (1), R. Cirami (2), G. Calderone (2), D. Del Moro (3), P. Romano (4), I. Coretti (2), F. Giorgi (1 ), V. Baldini (2), P. Di Marcantonio (2), L. Giovannelli (3), S. L. Guglielmino (4), M. Murabito (1), M. Oliviero (5), F. Pedichini (1), R. Piazzesi (1), M. Aliverti (6), E. M. Redaelli (6), F. Berrilli (3), F. Zuccarello (7)

The Interferometric BIdimensional Spectrometer IBIS, which operated until 2019 at the Dunn Solar Telescope, is undergoing a hardware and software revision that will allow soon to perform new measurements of the magnetic and velocity fields in solar atmosphere at high spatial, spectral and temporal resolution. We present the opto-mechanical layout and control system for the new instrument, called IBIS 2.0, which have been developed to interface it to the Vacuum Tower Telescope, and describe future steps.

Report on activities carried out in WP3

Status of WP2 and WP9 of SOLARNET as reported by the WP leader.

P. Costa, I. Ermolli, F. Giorgi, S.L. Guglielmino, M. Murabito, M. Oliviero, G. Viavattene

We describe the ongoing upgrade of the INAF small telescopes providing full-disc observations at various bands of the visible spectrum of the Sun, specifically of the Catania, Rome-PSPT, and VAMOS telescopes. The acquisition system of the former has been updated to provide observations in the Hα line with pixel scale of 1” and cadence up to 24 images per sec, whose quality and format allow easy exploitation of the Lucky-imaging and flare detection techniques developed within the SPRING project. The update of the control system of the PSPT is also under study to ensure the continuation of the time series of Ca II K and continuum observations started 25 years ago. Finally, the opto-mechanical layout of the VAMOS telescope has been revised to improve the spatial resolution of the Dopplergrams, magnetograms, and intensity images obtained with potassium MOF cells at a 25 cm aperture telescope.

Design considerations for a small full disk telescope with a Fabry Pérot interferometer in front

In this presentation I give an overview on the SOLARNET WP8 workpackage SPRING and its current status. Furthermore, the objectives of the meeting are presented.

Several generalizations of the well-known fluid model of Braginskii (Rev. of Plasma Phys., 1965) are considered. We use the Landau collisional operator and the moment method of Grad. We focus on the 21-moment model that is analogous to the Braginskii model, and we also consider a 22-moment model. Both models are formulated for general multi-species plasmas with arbitrary masses and temperatures, where all the fluid moments are described by their evolution equations. The 21-moment model contains two “heat flux vectors” (3rd and 5th-order moments) and two “viscosity-tensors” (2nd and 4th-order moments). The Braginskii model is then obtained as a particular case of a one ion-electron plasma with similar temperatures, with de-coupled heat fluxes and viscosity-tensors expressed in a quasi-static approximation. See more at https://espos.stream/2022/06/23/Hunana/ .

Introduction to the Forum plus a presentation of the SOLARNET Trans-National Access Programme

SOLARNET WP8 participants

Large, high-resolution solar telescopes admit only a small field of view. However, context data showing the big picture of the dynamics and magnetism at different heights of the solar atmosphere are equally important to understand the Sun in general. Real-time information about the variation of surface velocity, magnetic field, and intensity at different solar layers is an essential input to fundamental solar physics and space weather prediction. There is a consensus that a worldwide distributed network of a suite of small, dedicated telescopes which observe the entire solar disk is needed to obtain these data on a continuous basis. In this talk, I will report about the current status of designing such a network SPRING which is currently developed under SOLARNET (High-resolution Solar Physics Network). The key scientific products of this facility will be arc-second resolution images of the Sun in various wavelengths, synoptic vector magnetic fields, synoptic surface velocity fields wit

Relativistic jets and accretion disks from Black Hole (BH) sources, such as active galaxies, are among the most extreme particle accelerators known, producing very high energy emission. Only recently have we begun to comprehend the prevailing physical processes near these BHs, thanks to the combination of theory, numerical simulations, and observations. These investigations aim to solve significant enigmas, such as the origin of gamma-ray flares and ultra-high-energy cosmic rays. Within the inner regions of these BH sources, magnetic fields play a dominant role, and magnetic reconnection emerges as a highly plausible, if not the sole, mechanism responsible for accelerating particles to extreme energies. In this presentation, I will focus on magnetic reconnection driven by turbulence surrounding BH sources. Our latest findings, based on three-dimensional global magnetohydrodynamic relativistic simulations and the injection of test particles, demonstrate the efficiency of this mechanism