Tor vergata Synoptic Solar Telescope: preliminary optical design and spectral characterization

Calchetti, D.; Viavattene, Giorgio; Berrilli, F.; Moro, D. Del; Giovannelli, Luca; Oliviero, M.

doi:10.1088/1742-6596/1548/1/012005

Cited by 6 publications

(6 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Moreover, the small dependence on the exact threshold value, due to the topological definition of complexity rather than to an accurate estimate of the magnetic energy reservoir, allows a simpler application in the case of ground-based synoptic telescopes (e.g. Elsworth et al 2015;Gosain et al 2018;Hill et al 2019;Giovannelli et al 2020;Viavattene et al 2020;Calchetti et al 2020).…”

Section: Value Algorithmmentioning

confidence: 99%

Flare Forecasting Algorithms Based on High-Gradient Polarity Inversion Lines in Active Regions

Cicogna,

Berrilli,

Calchetti

et al. 2021

Preprint

View full text Add to dashboard Cite

Solar flares emanate from solar active regions hosting complex and strong bipolar magnetic fluxes. Estimating the probability of an active region to flare and defining reliable precursors of intense flares is an extremely challenging task in the space weather field. In this work, we focus on two metrics as flare precursors, the unsigned flux R, tested on MDI/SOHO data and one of the most used parameters for flare forecasting applications, and a novel topological parameter D representing the complexity of a solar active region. More in detail, we propose an algorithm for the computation of the R value which exploits the higher spatial resolution of HMI maps. This algorithm leads to a differently computed R value, whose functionality is tested on a set of cycle 24th solar flares. Furthermore, we introduce a topological parameter based on the automatic recognition of magnetic polarity-inversion lines in identified active regions, and able to evaluate its magnetic topological complexity. We use both a heuristic approach and a supervised machine learning method to validate the effectiveness of these two descriptors to predict the occurrence of X-or M-class flares in a given solar active region during the following 24 hours period. Our feature ranking analysis shows that both parameters play a significant role in prediction performances. Moreover, the analysis demonstrates that the new topological parameter D is the only one, among 173 overall predictors, which is always present for all test subsets and is systematically ranked within the top-ten positions in all tests concerning the computation of the weighs with which each predictor impacts the flare forecasting.

show abstract

Section: Value Algorithmmentioning

confidence: 99%

Flare Forecasting Algorithms Based on High-Gradient Polarity Inversion Lines in Active Regions

Cicogna,

Berrilli,

Calchetti

et al. 2021

Preprint

View full text Add to dashboard Cite

show abstract

“…After the Doppler modulator, the acquisition of both polarization states in the R and B wings (R + , R − , B + and B − ) allows the estimate of the LoS velocity, i.e., Dopplergrams, (D) and LoS magnetic field (M) of the Sun (e.g. Calchetti et al, 2020):…”

Section: The Potassium Mof Channelmentioning

confidence: 99%

“…This is mandatory to maintain a longitudinal temperature gradient inside the cell and to avoid the heat up of the whole MOF channel. For further details on the spectral calibration procedure, see Calchetti et al (2020).…”

Section: The Potassium Mof Channelmentioning

confidence: 99%

The Tor Vergata Synoptic Solar Telescope (TSST): A robotic, compact facility for solar full disk imaging

Giovannelli

Berrilli

Calchetti

et al. 2020

J. Space Weather Space Clim.

View full text Add to dashboard Cite

By the continuous multi-line observation of the solar atmosphere, it is possible to infer the magnetic and dynamical status of the Sun. This activity is essential to identify the possible precursors of space weather events, such as flare or coronal mass ejections. We describe the design and assembly of TSST (Tor Vergata Synoptic Solar Telescope), a robotic synoptic telescope currently composed of two main full-disk instruments, a H telescope and a Potassium (KI D1) Magneto-Optical Filter (MOF)-based telescope operating at 769.9 nm. TSST is designed to be later upgraded with a second MOF channel. This paper describes the TSST concepts and presents the first light observation carried out in February 2020. We show that TSST is a low-cost robotic facility able to achieve the necessary data for the study of precursors of space weather events (using the magnetic and velocity maps by the MOF telescope) and fast flare detection (by the H telescope) to support Space Weather investigation and services.

show abstract

“…In Fig. 1, we report the spectral transmission profile of our spectral MOF cell in the Potassium KI D1 spectral line at 769.9 nm [16]. Varying the heating temperature of the two wells, and so the vapor density inside the cell, the amplitude and the wavelength of the two Macaluso-Corbino peaks can be varied.…”

Section: -The Magneto-optical Filters Theorymentioning

confidence: 99%

Optical design of the Tor vergata Synoptic Solar Telescope (TSST)

Viavattene¹,

Calchetti²,

Berrilli³

et al. 2020

Preprint

View full text Add to dashboard Cite

Synoptic full-disk solar telescope are fundamental instruments for present and future Solar Physics and Space Weather. They are typically used to study and monitor the solar activity by using high temporal cadence observations at different wavelength. The TSST (Tor vergata Synoptic Solar Telescope) is a new synoptic telescope composed of two spectral channels: an Hα (656.3 nm) telescope and a Magneto Optical Filter (MOF)-based telescope in the Potassium (KI D1) absorption spectral line at 769.9 nm. Hα observations are fundamental for the identification of flaring regions. The MOF-based telescope will produce line of sight magnetograms and dopplergrams of the solar photosphere, which are respectively used to study the magnetic field's geometry in active regions and dynamics of the solar atmosphere. In this work, we present an overview on the TSST and the optical design and characteristics of the MOF-based telescope, whose optical scheme is a double-Keplerian 80mm refractor with an aberration-free imaging lens.

show abstract

Tor vergata Synoptic Solar Telescope: preliminary optical design and spectral characterization

Cited by 6 publications

References 20 publications

Flare Forecasting Algorithms Based on High-Gradient Polarity Inversion Lines in Active Regions

Flare Forecasting Algorithms Based on High-Gradient Polarity Inversion Lines in Active Regions

The Tor Vergata Synoptic Solar Telescope (TSST): A robotic, compact facility for solar full disk imaging

Optical design of the Tor vergata Synoptic Solar Telescope (TSST)

Contact Info

Product

Resources

About