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The inventory of the taxa collected during the annual field trip of the working group for Floristics, Systematics and Evolution of the Italian Botanical Society is reported. The field trip was held in 2016 along the Velino and Aterno valleys located between Lazio and Abruzzo administrative regions (central Italy). The flora documented for the studied area amounts to 629 specific and subspecific taxa (including two hybrids) belonging to 300 genera and 69 families. Thirty-eight taxa are endemic to Italy, and only 16 alien taxa were detected. Thirty-eight taxa are included in the IUCN Red List of the Italian Flora. Twenty-four taxa have to be considered as floristic novelties because either new or confirmed for the regional flora of Lazio or Abruzzo. In particular, 15 taxa are new and 6 are confirmed for Lazio. Regarding Abruzzo, 2 taxa are new for the regional flora and one is confirmed. Furthermore, the alien status in Lazio has been updated for one taxon.

At the beginning of 2020 the SPIDER Cs Oven 03 was tested on the CAesium Test Stand (CATS). This document concerns the description of the functional tests carried out on this oven and the presentation of the obtained experimental results. It is submitted as deliverable AWP21- DMCS/D1.

The Divertor Tokamak Test (DTT) facility is an experimental fusion facility under design stage at ENEA Frascati, Italy dedicated to the optimisation of the divertor, a key component of thermonuclear fusion reactors exposed to extreme environments of temperature and irradiation. DTT is an actively cooled reactor that will exploit the alternation of ultrapure water and borated water in the Vacuum Vessel (VV). The use of borated water in fusion reactors, JT-60SA and DTT, using 95% 10B as H3BO3 at 40-80 °C has the primary function of shielding the superconducting coils by neutrons generated in the tokamak plasma during fusion reactions. The boric acid quantities needed in the DTT and JT-60SA fusion reactors are respectively 8000 ppm and 13400 ppm in B, which is well above the operational experience seen in any operating pressurized water reactor (PWR). Experimental work and modelling is undergoing to ensure best performance of the cooling circuit given the gap in knowledge between conventional PWRs water chemistry and the DTT VV set up. A first assessment for DTT VV water chemistry was performed using the chemistry module of an activated corrosion products (ACPs) assessment computer code. Water pH and SS316L alloying elements solubility were compared considering ultrapure water (UPW), borated water and borated water neutralised with LiOH. Stabilisation of 8000 ppm B with 30 ppm Li was considered a good option as pH=6-6.11 at 40-80 °C compared to a pH=4.17-4.23 without LiOH addition. Fe, Ni, Co, Cr and Mn solubility at 40-80 °C were 3 orders of magnitude larger in the borated water compared to the use of only UPW. The addition of 30 ppm Li is, however, beyond the safe margins currently established for PWRs. Slight improvement in terms of solubility was observed in the borated water scenario with the addition of 4 ppm Li compared to no addition of LiOH at 60 °C, so the use of additives is being reconsidered. Experiments to monitor water pH and metallic ions release in solution using Inductively coupled plasma mass spectrometry were also performed to confirm results obtained from the computer code.

Abstract The Euganean Hills are a well-known refugee site for thermophilous woody flora in northern Italy. Among the species recorded here, there is Quercus dalechampii. The Euganean Hills are the only northern Italy site where the occurrence of this oak species is considered. The aim of this paper was to verify the presence of Q. dalechampii in the study area and to select possible diagnostic morphological traits that are usable to distinguish it from Q. petraea and Q. pubescens. Forest stands dominated by Q. petraea, Q. pubescens, and the presumed Q. dalechampii were sampled using the phytosociological approach to highlight their ecological features. Leaf and fruit material from 104 oak individuals was analysed from a macro-morphological and micro-morphological point of view. Leaf shape was also analysed using the geometric morphometric approach. All multivariate analysis procedures applied on the matrices of leaf and fruit traits highlighted two main clusters of morphological diversity. One was restricted to Q. pubescens individuals, and the other one was a mix of Q. petraea and presumed Q. dalechampii individuals. According to the twig and leaf trichome traits, all presumed Q. dalechampii individuals were classified as belonging to the Q. petraea collective group. Morphological differences between Q. petraea and presumed Q. dalechampii were considered not significant. In conclusion, the occurrence of a third oak species, in addition to Q. petraea and Q. pubescens, was not confirmed for the study area by the results of this paper. Graphic abstract

Observation of a transient, in Cs-free regime and long term NIO1 operation, led to the development of stabilization techniques, including conditioning (with oxygen or other gases, as argon, nitrogen, and xenon), interleaved with days of use of H2 as a process gas. Stabilization of transients gave more H- current and less plasma luminosity. After installation of a cesium oven, some additional increase (up to a factor of 2 reaching an average about 50 A/m2) of current was observed, but effect saturates at a moderate oven reservoir temperature. Obtained beam optics will be compared with theoretical expectation and old results in the Cs-free regime in similar conditions (as source voltage, often set to 11 kV). In both regimes, central beamlet apparent density is larger, possibly because a bias plate BP mask reduces side ones. Further improvements including long term conditioning of oven, modification of BP mask and of Cs pipe nozzle (with supporting simulations) are discussed.

In 2018 the activity under the RF R&D task 5.8 of the 2018 Work Programme was addressed to the characterization of the voltage hold off capability of different RF driver mockups on the High Voltage Radio Frequency Test Facility (HVRFTF). Particular effort was addressed to review the facility layout and to improve its high voltage RF circuit in terms of impedance matching, frequency tuning capability, RF power available and protection against fault in circuit components. Furthermore the set of diagnostic tools was improved with a plasma light sensor and a camera. Their respective signals and images, along with the gas pressure signal (already available as diagnostic since 2016) are sent to the data acquisition system.

The ITER Heating Neutral Beam (HNB) injector is required to deliver 16.7 MW of power into the plasma from a neutralised beam of H-/D- negative ions, produced by an RF source and accelerated up to 1 MeV. To enhance the H-/D- production, the ion source needs to be coated with caesium to reduce its work function. Cs must be routinely evaporated in the source by means of dedicated ovens embedded in the source. Controlling and monitoring the evaporation rate of caesium inside the source is fundamental to attain the desired performances on the ITER HNB. In the Neutral Beam Test Facility at Consorzio RFX the prototype RF negative ion source SPIDER has been developed and built. Currently SPIDER is in operation. In SPIDER, liquid Cs based ovens will be used to inject Cs vapours inside the source. The CAesium Test Stand (CATS) has been specifically designed and set up for testing, commissioning, and characterizing Cs ovens in vacuum, in terms of repeatability of the Cs evaporation and deposition onto surfaces. To this aim, a set of diagnostics were installed: fixed Surface Ionization Detectors (SID), embedded in the oven and located in front of the oven nozzle apertures, movable SIDs, to reconstruct the angular distribution of the emission, a quartz microbalance, at a fixed position to provide the cumulated caesium flux, and the laser absorption spectroscopy, to measure the line-integrated caesium density. The poster will present the CATS set- up with a description of the layout and the present configuration of the diagnostic set-up and future upgrades.

This report describes the activities carried out within the subtask T5.7 of the Work Programme WP2019 at the High Voltage Padova Test Facility HVPTF and on the new High Voltage Short Gap Test Facility HVSGTF. The activities mainly consisted in: 1) Test of two electrodes with double-polarity configurations (Common Mode Voltage tests). 2) Test of electropolished electrodes 3) Tests with cathode covered by a thick alumina cap 4) Removal of dust deposited inside the vacuum vessel before starting the vacuum system: 5) Tests with specific shaped electrodes designed to understand the effect of the mutual exchange of charged particles between electrodes are still in progress 6) Tests of Non Evaporable Getter (NEG) pumps at high voltage in high vacuum are still in progress 7) Ordinary Maintenance of the vacuum pump system 8) Tests in HVSGTF to measure the Fowler-Nordheim emission current from stainless steel electrodes. The activities mentioned in points #5 and #6 are still in progress and will be completed next year. Concerning the other experiments, the main outcomes can be reported as follows: 1) CMV tests showed that the main microdischarge activity of the electrodes appears to be related to phenomena involving only a single power supply unit and the vacuum chamber, rather than the two electrodes under test 2) Test of electropolished electrodes, tests with cathode covered by a thick alumina cap and Removal of dust deposited inside the vacuum vessel did not indicate significant improvements of voltage holding 3) The measurement of the Fowler-Nordheim emission current from stainless steel electrodes showed a behaviour much more complex than expected and their analysis is in progress.

The MITICA Central Safety System (MITICA CSS) implements a set of important protection functions related to personnel health and safety, both during and outside the operation of the MITICA test bed, providing continuous monitoring of potentially dangerous events, automated protection actions, and logging of events and data relevant for safety of people. The Technical Specification for the call for tender of the supply of the MITICA CSS was drafted in 2017 (ref. RFX_MITICA_TS_041), but some important details were still to be defined, also depending on the status of the procurement of plant systems interfacing with MITICA CSS and according to the experience acquired with SPIDER CSS installation. This document is intended to be the report of the main activities related to MITICA safety carried out in 2019, in order to better define the aspects needed to pass from the MITICA CSS "Draft" to the "Detailed" Techinical Specification.

At the end of January2019 the procurement of the three SPIDER Cs ovens (series production -Batch B) was completed and the ovens were delivered to PRIMA site.TwoSPIDER Cs ovens (Oven 01 and Oven 02) were tested on CAesium Test Stand (CATS).This document concernsthedescription of the functional test carried out on these twoovens and the experimental resultsand represent the deliverable T5.9 -P1.1 Report of tests on Cs ovensof the Work Programme 2019.Moreover, analyses on Cs residual after functional tests are also reported in this document and represent the deliverable T5.4/P1.2 -ICMATE-CNR Activity report on caesium chemistry investigations.

The MITICA Central Safety System (MITICA CSS) implements a set of important protection functions related to personnel health and safety, both during and outside the operation of the MITICA test bed, providing continuous monitoring of potentially dangerous events, automated protection actions, and logging of events and data relevant for safety of people. The Technical Specification for the call for tender of the supply of the MITICA CSS was drafted in 2017 (ref. RFX_MITICA_TS_041), but some important details were still to be defined, also depending on the status of the procurement of plant systems interfacing with MITICA CSS. This document is intended to be the report of the main activities related to MITICA safety carried out in 2018, in order to better define the aspects needed to pass from the MITICA CSS "Draft" to the "Detailed" Techinical Specification.

Caesiated Molybdenum samples will be prepared in CATS [1] for chemical analysis of the caesium layer. This document reports on the preparatory activities for the design of the sample holder, and for the definition of procedures for sample preparation and caesiation.

This document concerns the description of the CAesium Test Stand (CATS) and the testing activities on the SPIDER Cs ovens (prototype and series production). The setup of CATS and the thermal test on Cs oven prototype were carried out under WP2017 T5.9. During WP2018 CATS has been upgraded with implementation of new diagnostics and components, it has been commissioned for Cs operation and Cs flux tests on Cs oven prototype were carried out.

This report describes the main activities carried out at the High Voltage Padova Test Facility HVPTF in 2017. According with the Work Program (WP) 2017, the activities were focused mainly in: - Studying of the X-ray spectra to investigate the nature of the physical phenomena which occurs during the high voltage conditioning - Implementing an effective automatic procedure to define a reproducible high voltage test Method - testing alternative conditioning techniques to treat the electrode surfaces before applying the DC high voltage in high vacuum - comparing of breakdown voltage statistics from QST labs and HVPTF - calibrating the Voltages measured by the high voltage power supplies - Extending the duration of the High Voltage tests - Concluding the HV tests of a post insulator prototype foreseen in WP2016 As usual, activities concerning ordinary maintenance on the vacuum plant and controlling system have been done during the year.

The present report, summarizes the work carried out in 2016 on the NIO1 experiment at Consorzio RFX in Padova, Italy. Experimental campaigns will be presented together with the modelling activities and the activities carried out on various plants.

This report describes the main activities carried o ut at the High Voltage Padova Test Facility HVPTF i n 2016. According with the Work Program (WP) 2016, the act ivities were focused mainly: to analyse the occurre nce of the micro discharges during the high voltage con ditioning procedure, to study the X (and gamma) ray spectra emitted during the high voltage conditionin g. The tests of the post insulator prototypes have been postponed due to the impossibility to access the la boratory from the 6 th Oct. to 16 th Nov. As usual, activities concerning ordinary maintenanc e on the vacuum plant and controlling system have b een done during the year.

This report describes the activities carried out at the High Voltage Padova Test Facility HVPTF in 2015. The activities were focused mainly: to support the R&D of the MITICA post insulators, to repair a lea kage of insulating oil from both power supplies feedthrough s, to improve the acquisition system and to continu e the high voltage test program with different electrode shapes and gap lengths, in double polarity configuration.

Voltage holding in vacuum is one of the most critical issues for the experiment MITICA (Megavolt ITer Injector & Concept Advancement), aimed at realizing the 40 A - 1 MegaVolt prototype of the ITER HNB at the Consorzio RFX in Padova. For this reason, boosting the R&D on this specific problem has been identified as a priority to attain the success of the MITICA experiment, by means of the realization of the dedicated Laboratory HVPTF - High Voltage Padova Test Facility. This Laboratory is capable to carry experiments up to 800 kV, and recently has been equipped with a new data acquisition system. The improvement of this system, formerly based on optical RS232 data transmission, resulted necessary in order to better investigate the transient phenomena (bursts) related to the voltage conditioning. It acquires from the probes Current, X ray dose and Pressure, whose analysis helps in the understanding of the mechanism of the production of such bursts. The system is presently capable to acquire up to 8 analogue measurements sampled up to 10kHz. To minimize conducted EMI, the system is fully insulated to ground, with the electronic cards fed by a battery Power Supply. The environment is LabView v.13 for the data acquisition, while for data visualization and post processing analyses, the MDS-PLUS v.7.0-42 tool has been employed.

The present report, summarizes the work carried out in 2015 on the NIO1 experiment at Consorzio RFX in Padova, Italy. Experimental campaigns will be presented together with the modelling activities and the activities carried out on various plants.

This technical note summarizes the R&D activities dedicated to the procurement of the SPIDER high voltage insulating pipes which are part of the Beam Source cooling circuit. The insulating pipes are the physical connections between PRIMA Cooling Plant (F4E-OPE-351 Procurement) and "Supply of the Beam Source, vacuum vessel and handling tool of the SPIDER experiment" (F4E-OPE-081 Procurement). The activity has been focused on electrical, thermal and pressure tests. The R&D results have been the basis for the design of these flexible connections. In case of grounded in-vessel components (e.g. Grounded Grid, Electron Dump, Beam Dump) the connections will be made by flexible stainless steel pipes (included in PRIMA Cooling Plant Procurement) and are mentioned here for information only.