Multiparametric advanced research tool for meteo satellites data interfacing with space observation of ultra high energy cosmic rays

To approach the study of the cosmic rays in the energy range E > 1020 eV, the upper end of the spectrum observed to date, with a large statistical significance (103 events/year), and hence address the solution of several astrophysical and cosmological problems related to their existence and behaviour, a new generation of experiments will probably have to be conceived and realised. They will be based on the observation and measurements of cosmic rays from space. The extremely low rate of these events (∼ 1 event/(century × km2 × sr)) imposes a very large effective area to be monitored, of the order of 105 km2, as an observational requirement to meet the target statistics. The Extreme Universe Space Observatory (EUSO)mission has been proposed as the precursor of this new generation of experiments. Its approach consists in fact in looking downwards to the Earth atmosphere by means of a large field-of-view telescope accommodated aboard an orbiting satellite. The fluorescence strike produced by a cosmic ray through the atmosphere will be recorded by the detector, which will reconstruct the kinematical and dynamical features of the primary cosmic ray. The atmosphere acts therefore as an active target for the detectable event. A strategic tool for the success of EUSO as well as for all the experiments of its category will be a correct and detailed atmospheric sounding system, in order to monitor the atmospheric parameters within the field-of-view of the telescope. Beside an on-board measurement by means of dedicated devices such an infrared camera (IR)and possibly a LIDAR (LIght Detection And Ranging)coupled to the main instrument, the Atmosphere Sounding will take advantage from the continuous observation of the atmospheric parameters given by the orbiting meteorological satellites. Their databases have thus to be interfaced to the experimental data and used picking-up the relevant data according to the space and time coordinates corresponding to each triggered event. The present work outlines a software module (MARVIN-Multiparametric Advanced Research tool for Visualisation In the Network) able to build-up such an interface, and shows a preliminary implementation of it, using a sample of existing satellites and ISCCP meteorological data collection. It has been developed during the phase A study of the EUSO mission but is general enough to be adapted to different missions observing the Earth atmosphere from space

Cosmic ray physics with the ARGO-YBJ experiment

The main scientific goals of the ARGO-YBJ experiment are ray astronomy with a few hundreds GeV energy threshold and cosmic ray physics below and around the knee of the primary energy spectrum (10**12−10**16 eV), where the transition from direct to indirect measurement techniques takes place. The ARGO-YBJ experiment, located at the Cosmic Ray Observatory of Yangbajing (Tibet, P.R. of China, 4 300 m a.s.l.), is an unconventional Extensive Air Shower array of about 6,700 m2 of active area, the only one exploiting the full-coverage technique at very high altitude currently in operation. The detector space-time granularity, performance and location offer a unique chance to make a detailed study of the structure of cosmic ray showers, in particular of the hadronic component. In this work we will focus on the main experimental results concerning cosmic ray and hadronic interaction physics: primary cosmic ray energy spectrum, antiproton over proton ratio, anisotropy in the cosmic ray flux and proton-air cross-section. Moreover, the possible data analysis improvements based on the use of all detailed information on the shower front (curvature, time width, rise time and so on), as well as the extension of the investigable energy range, allowed by the analog RPC readout, will be pointed out

Hydrogen sorption properties of the composed system calcium hydride – magnesium boride

The hydrogen sorption properties of the calcium hydride – magnesium boride system as evaluated by manometric and calorimetric analyses are discussed

Evaluation of saltwork ponds operation through brine characterization and geochemical modelling using PHREEQC code integrating the Pitzer correction

Seawater represents a potential resource for the extraction of salts and raw materials [1]. About one-third of the global table-salt production is manufactured in solar saltworks [2], being the most representative product of seawater processing. However, other valuable compounds such as Magnesium, Lithium and trace elements belonging to the alkaline/alkaline-earth metals (e.g. Rb, Cs, Sr) and transition/post-transition metals (e.g. Co, Ga, Ge) are present. Many of these elements are included in the EU Critical Raw Materials (CRM) list, grouping natural assets classified as fundamental for the wealth of the socio-economic structure of Europe [3]. In saltworks, natural evaporation of seawater leads to fractional crystallization of Calcium and Sodium salts and the generation of residual brines called “bitterns” with electrolytes concentrations up to 20-40 times higher than seawater. In this complex crystallization process, preliminary precipitation of Calcium based minerals is the basis for the enhancement of sodium chloride recovery and purity. Along the sequence of evaporation and concentration stages, the fate of the minor components (e.g CRMs) has not been extensively studied so far. With this respect, it is fundamental to deeply understand the potential formation of mineral phases involving such minor trace elements. Pitzer model accounting for an equilibrium approach for high ionic strength can be a valuable tool for salterns modelling by allowing a reliable description of the precipitation and crystallization reactions occurring there [4]. In the present work, PHREEQC incorporating the Pitzer model was used as equilibrium computation tool to describe the minerals precipitation pathway along the different ponds of a saltwork. The Trapani saltworks (SOSALT, Italy), where the "Sea Salt of Trapani" is produced was used as case study. The validation of the obtained results was performed by using a monitoring campaign by withdrawing samples from each pond belonging to different evaporation stages of the production process. The salterns have been fully characterized to determine their composition. A good agreement was obtained between the model prediction and the analytical characterization. Finally, an attempt to provide indications for table-salt recovery and purity maximization has been done and insights on trace elements enrichment were given

Potentials for critical raw materials recovery from Mediterranean saltworks bitterns

Minerals extraction from seawater brines is currently regarded as the most practical approach to reduce European dependency from the import of many Critical Raw Materials. The technical feasibility of such approach has been widely demonstrated in several different research and development projects but the economic sustainability has always been found to depend on the local demand for sodium chloride, which is always the most abundant product of the extraction. Starting from this crucial node, the SEArcularMINE project has investigated the possibility to use the residual brines originated by sea-salt extraction in traditional saltworks, regarded as an already well-established marketplace. The Mediterranean area as a whole, can rely on a diffused industry including South-European coast, North-African and Close East coast and portions of the Atlantic regions. Additionally, many inland salt-lakes and subsoil waters are traditionally operated in the same way as the coastal facilities to produce solar-salt. Interestingly, each saltworks have a slightly different approach, adapted to feed quality or local climate conditions. Accordingly, different types of brine are produced, having unique features. These “bitterns” are extremely interesting to characterize, focusing on their hidden potential. In this work, an extensive analytical campaign has been conducted exploiting the wide saltworks network established within the SEArcularMINE project. Main results are here reported, highlighting the possibility of contributing to secure the access to some Critical Raw Materials for E

Layout and performance of the RPCs used in the ARGO-YBJ experiment

The layout of the RPCs, used in the Argo-YBJ experiment to image with a high space-time granularity the atmospheric shower, is described in this paper. The detector has been assembled to provide both digital and analog informations in order to cover a wide particle density range with a time accuracy of 1 ns. The experimental results obtained operating the chambers in streamer mode at sea level with a standard gas mixture are presented

Gamma ray sources observation with the ARGO-YBJ detector

In this paper we report on the observations of TeV gamma ray sources performed by the air shower detector ARGO-YBJ. The objects studied in this work are the blazar Markarian 421 and the extended galactic source MGROJ1908+06, monitored during 2 years of operation. Mrk421 has been detected by ARGO-YBJ with a statistical significance of 11 standard deviations. The observed TeV emission was highly variable, showing large enhancements of the flux during active periods. The study of the spectral behaviour during flares revealed a positive correlation of the hardness with the flux, as already reported in the past by the Whipple telescope, suggesting that this is a long term property of the source. ARGO-YBJ observed a strong correlation between TeV gamma rays and the X-ray flux measured by RXTM/ASM and SWIFT/BAT during the whole period, with a time lag compatible with zero, supporting the one-zone SSC model to describe the emission mechanism. MGROJ1908+06 has been detected by ARGO-YBJ with 5 standard deviation of significance. From our data the source appears extended and the measured extension is ext=0.48+0.26−0.28, in agreement with a previous HESS observation. The average flux is in marginal agreement with that reported by MILAGRO, but significantly higher than that obtained by HESS, suggesting a possible flux variability

Search for Gamma Ray Bursts with the ARGO-YBJ detector in scaler mode

We report on the search for gamma ray bursts (GRBs) in the energy range 1–100 GeV in coincidence with the prompt emission detected by satellites using the Astrophysical Radiation with Ground-based Observatory at YangBaJing (ARGO-YBJ) air shower detector. Thanks to its mountain location (Yangbajing, Tibet, People’s Republic of China, 4300 m above sea level), active surface (∼6700 m2 of Resistive Plate Chambers), and large field of view (∼2 sr, limited only by the atmospheric absorption), the ARGO-YBJ air shower detector is particularly suitable for the detection of unpredictable and short duration events such as GRBs. The search is carried out using the “single particle technique,” i.e., counting all the particles hitting the detector without measurement of the energy and arrival direction of the primary gamma rays. Between 2004 December 17 and 2009 April 7, 81 GRBs detected by satellites occurred within the field of view of ARGO-YBJ (zenith angle θ 1 GeV counterpart in the ARGO-YBJ data finding no statistically significant emission. With a lack of detected spectra in this energy range fluence upper limits are profitable, especially when the redshift is known and the correction for the extragalactic absorption can be considered. The obtained fluence upper limits reach values as low as 10^{−5} erg cm^{−2} in the 1–100 GeV energy region. Besides this individual search for a higher energy counterpart, a statistical study of the stack of all the GRBs both in time and in phase was made, looking for a common feature in the GRB high-energy emission. No significant signal has been detected

Results and overview from the ARGO-YBJ experiment

Within a Collaboration Agreement between INFN and CAS (Chinese Academy of Science), the ARGO-YBJ experiment is completely installed and has been in stable data taking since November 2007 at the YangBaJing Cosmic Ray Laboratory (Tibet, P.R. China, 4300 m a.s.l.). In this paper we report a few selected results in γ−ray Astronomy and Cosmic Ray Physics