We present the main parameters, design features and optical characterization of the GrAnada LIghtning Ultrafast Spectrograph (GALIUS): a portable, ground-based spectrographic system intended for the analysis of the spectroscopic signature of lightning. It has been designed to measure the spectra of the light emitted from natural and triggered lightning and artificial electrostatic discharges at recording speeds up to 2.1 Mfps. It includes a set of four interchangeable grisms covering different spectral ranges (from 375 nm to 854.5 nm) with spectral resolutions from 0.29 to 0.76 nm. A set of ten collector lenses allows to record the spectrum of electrostatic discharges and lightning in different scenarios.

We present spectroscopic diagnostic methods that allow us to estimate the gas and the electron temperature in emerged lightning stroke channels (from thunderclouds) observed by the photometers and cameras of the Atmosphere Space Interaction Monitor (ASIM). We identify the species (molecules, atoms and ions) producing light emission in different wavelengths, and how the blue (337 ± 2 nm), red (777.4 ± 2.5 nm) and ultraviolet (180–230 nm) optical emissions captured by ASIM photometers change as a function of the temperature in the lightning stroke channel. We find good agreement between the light curves of the emerged lightning observed by ASIM and the synthetic ones obtained from calculated spectra. Our results suggest that (i) early stage (high temperature > 20,000 K) emerged lightning strokes at high altitude can contribute to the optical signals measured by the PH2 photometer (180–230 nm), (ii) intermediate stage (mid temperatures, 6000–21,000 K) emerged lightning strokes can produce 777.4 nm near-infrared radiation (observable by PH3) exhibiting higher intensity than PH1 observable N2 SPS between ∼6000 K and ∼8000 K, and than ion optical emissions (336.734 nm and 337.714 nm) between ∼16,000 K and ∼21,000 K, (iii) from ∼16,000 K to 35,000 K, neutral oxygen 777.4 nm radiation and ion emissions at 336.734 nm and 337.714 nm can be simultaneoulsy observed but 777.4 nm dominates only between ∼16,000 K and ∼21,000 K, (iv) the availability of detections with a narrow 0.5 nm gap filtered photometer (336.75–337.25 nm), with the same or better sensitivity than PH1 in ASIM-MMIA but with a central wavelength at exactly 337.0 nm (the strongest N2 SPS transition), would give access to the late stage of lightning strokes (emerged or not) when temperatures are between 8000 K and 5000 K (or lower for a photometer with better sensitivity than PH1 in ASIM-MMIA) when the production of nitrogen oxides (NOx) and hydroxyl radicals (OH) maximizes.

Slitless spectroscopy is a well known technique to analyze the absortion and emission of light coming from a narrow source, that consists of an optical system including a diffraction element and a sensor. It is a very useful tool to analyze the spectrum of natural (

<p>The GrAnada Lightning Ultrafast Spectrograph (GALIUS) is a portable, ground-based slit spectrograph designed and developed at the Instituto de Astrofísica de Andalucía, in Granada, Spain. It is able to record spectra of natural and triggered lightning or lightning-like plasmas with submicrosecond time resolution in a spectral range from 380 nm to 854 nm. Our work shows GALIUS radial-resolved slit spectroscopy of 20 laboratory produced lightning-like discharges of 30 mm length and 8 ± 2 mm mean width, generated with an automated Wimshurst machine, being their mean peak voltage and current 32.70 kV and 149.58 A, respectively. We analyze the visible (645.0 - 663.0 nm) region operated at 900 kfps with 0.79 µs exposure time, spectral resolution better than 0.38 nm and spectral dispersion of 0.58 mm/px, that allows us to experimentally quantify the profiles of electron density and electron/gas temperature along the radial dimension of the lightning-like plasma channels and their temporal dynamics. To do so, we analyze the rows of the 2D spatial-spectral images of the heated channel of every lightning-like discharge, to follow the radial and temporal variation of neutral (atoms and molecules) and ion spectroscopic signatures. From these measurements we also estimate the evolution of the radial profiles of electrical conductivity, overpressure and populations of key chemical species(N<sub>2</sub>, NO, O<sub>2</sub>, OH, H<sub>2</sub>, N<sub>2</sub>O, NO<sub>2</sub>, HO<sub>2</sub>, O<sub>3</sub> and H<sub>2</sub>O) produced along the radius of the plasma channel.</p>

<p>The Instituto de Astrofísica de Andalucía (IAA) is the largest Astronomy Institute of the Consejo Superior de Investigaciones Científicas (CSIC). The creation of the Institute's Gender Equality Commission and the annual elaboration and approval of the Gender Equality Plan (GEP) of the IAA-CSIC since 2017 confirm the IAA support for inclusive initiatives in gender equality. In this presentation, I will show the effectiveness of the different GEPs over time, by analyzing the statistics segregated by gender of the main activities of the last years at IAA.</p>