Open Universe for Blazars: A new generation of astronomical products based on 14 years of Swift -XRT data

Aims. Open Universe for Blazars is a set of high-transparency multi-frequency data products for blazar science, and the tools designed to generate them. Blazars are drawing growing interest following the consolidation of their position as the most abundant type of source in the extragalactic very high-energy γ-ray sky, and because of their status as prime candidate sources in the nascent field of multi-messenger astrophysics. As such, blazar astrophysics is becoming increasingly data driven, depending on the integration and combined analysis of large quantities of data from the entire span of observational astrophysics techniques. The project was therefore chosen as one of the pilot activities within the United Nations Open Universe Initiative, whose objective is to stimulate a large increase in the accessibility and ease of utilisation of space science data for the worldwide benefit of scientific research, education, capacity building, and citizen science. Methods. Our aim is to deliver innovative data science tools for multi-messenger astrophysics. In this work we report on a data analysis pipeline called Swift-DeepSky based on the Swift XRTDAS software and the XIMAGE package, encapsulated into a Docker container. Swift-DeepSky downloads and reads low-level data, generates higher level products, detects X-ray sources, and estimates several intensity and spectral parameters for each detection, thus facilitating the generation of complete and up-to-date science-ready catalogues from an entire space-mission data set. Results. As a first application of our innovative approach, we present the results of a detailed X-ray image analysis based on Swift-DeepSky that was run on all Swift-XRT observations including a known blazar, carried out during the first 14 years of operations of the Neil Gehrels Swift Observatory. Short exposures executed within one week of each other have been added to increase sensitivity, which ranges between ∼1 × 10-12 and ∼1 × 10-14 erg cm-2 s-1 (0.3-10.0 keV). After cleaning for problematic fields, the resulting database includes over 27 000 images integrated in different X-ray bands, and a catalogue, called 1OUSXB, that provides intensity and spectral information for 33 396 X-ray sources, 8896 of which are single or multiple detections of 2308 distinct blazars. All the results can be accessed online in a variety of ways, from the Open Universe portal through Virtual Observatory services, via the VOU-Blazar tool and the SSDC SED builder. One of the most innovative aspects of this work is that the results can be easily reproduced and extended by anyone using the Docker version of the Swift-DeepSky pipeline, which runs on Linux, Mac, and Windows machines, and does not require any specific experience in X-ray data analysis.Fil: Giommi, Paolo. Università di Roma; Italia. International Center For Relativistic Astrophysics; Italia. Universitat Technical Zu Munich; AlemaniaFil: Brandt, C. H.. International Center For Relativistic Astrophysics; Italia. Jacobs University; AlemaniaFil: Barres de Almeida, U.. International Center For Relativistic Astrophysics; Italia. Centro Brasileiro de Pesquisas Físicas; BrasilFil: Pollock, A. M. T.. University of Sheffield; Reino UnidoFil: Arneodo, F.. New York University Abu Dhabi; Arabia SauditaFil: Chang, Y. L.. International Center For Relativistic Astrophysics; ItaliaFil: Civitarese, Enrique Osvaldo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; ArgentinaFil: de Angelis, Maria Cruz. Università di Roma; ItaliaFil: D'Elia, V.. Space Science Data Center; Italia. Osservatorio Astronomico di Roma; ItaliaFil: Del Rio Vera, J.. United Nations Office for Outer Space Affairs; AustraliaFil: Di Pippo, S.. United Nations Office for Outer Space Affairs; AustraliaFil: Middei, Riccardo. Università di Roma; ItaliaFil: Penacchioni, Ana Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; ArgentinaFil: Perri, M.. Osservatorio Astronomico di Roma; Italia. Space Science Data Center; ItaliaFil: Ruffini, Remo. International Center For Relativistic Astrophysics; ItaliaFil: Sahakyan, Narek. International Centre For Relativistic Astrophysics Network; ArmeniaFil: Turriziani, Sara. Computational Astrophysics Laboratory; Japó

The Open Universe survey of Swift-XRT GRB fields: a complete sample of HBL blazars

We have analysed all the X-ray images centred on Gamma Ray Bursts generated by Swift over the last 15 years using automatic tools that do not require any expertise in X-ray astronomy, producing results in excellent agreement with previous findings. This work, besides presenting the largest medium-deep survey of the X-ray sky and a complete sample of blazars, wishes to be a step in the direction of achieving the ultimate goal of the Open Universe Initiative, that is to enable non expert people to fully benefit of space science data, possibly extending the potential for scientific discovery, currently confined within a small number of highly specialised teams, to a much larger population. We have used the Swift_deepsky Docker container encapsulated pipeline to build the largest existing flux-limited and unbiased sample of serendipitous X-ray sources. Swift_deepsky runs on any laptop or desktop computer with a modern operating system. The tool automatically downloads the data and the calibration files from the archives, runs the official Swift analysis software and produces a number of results including images, the list of detected sources, X-ray fluxes, SED data, and spectral slope estimations. We used our source list to build the LogN-LogS of extra-galactic sources, which perfectly matches that estimated by other satellites. Combining our survey with multi-frequency data we selected a complete radio flux-density limited sample of High Energy Peaked (HBL) blazars.Comment: Accepted for publication in A&A. 8 pages, 7 figure

A multi-component flood risk assessment in the Maresme coast (NW Mediterranean)

Coastal regions are the areas most threatened by natural hazards, with floods being the most frequent and significant threat in terms of their induced impacts, and therefore, any management scheme requires their evaluation. In coastal areas, flooding is a hazard associated with various processes acting at different scales: coastal storms, flash floods, and sea level rise (SLR). In order to address the problem as a whole, this study presents a methodology to undertake a preliminary integrated risk assessment that determines the magnitude of the different flood processes (flash flood, marine storm, SLR) and their associated consequences, taking into account their temporal and spatial scales. The risk is quantified using specific indicators to assess the magnitude of the hazard (for each component) and the consequences in a common scale. This allows for a robust comparison of the spatial risk distribution along the coast in order to identify both the areas at greatest risk and the risk components that have the greatest impact. This methodology is applied on the Maresme coast (NW Mediterranean, Spain), which can be considered representative of developed areas of the Spanish Mediterranean coast. The results obtained characterise this coastline as an area of relatively low overall risk, although some hot spots have been identified with high-risk values, with flash flooding being the principal risk process

Anti‑algal activity of the 12‑5‑12 gemini surfactant results from its impact on the photosynthetic apparatus

A rapid amplification of algal population has a negative impact on the environment and the global economy. Thus, control of algal proliferation is an important issue and effective procedures which reduce algal blooms and control algal fouling are highly desired. Gemini surfactants are considered to have a low environmental impact, therefore they seem to be a promising group of detergents which could reduce algal blooms in water systems. Furthermore, due to their emulsifying properties they could replace algaecides added to antifouling paints and decrease algae adhesion to various surfaces. In this study the toxic effect of the 12-5-12 gemini surfactant was investigated on Chlorella cells and close attention was paid to a potential mechanism of its action. At the high cell density (10.05 × 107 cells/mL) a dose-dependent cell death was found and the IC50 value was reached at the concentration of 19.6 µmol/L after 72-h exposure to the surfactant. The decrease in chlorophyll autofluorescence shows that the photosynthetic apparatus seems to be the target of the tested compound. The presented studies indicate that gemini surfactants could effectively reduce algal blooms in water systems, and if added to paints, they could decrease algal growth on external building walls or other water immersed surfaces

Engineering the shoreline: Introducing environmentally friendly engineering techniques throughout the World

The guide, as part of the coastal management toolkit, contains the following main chapters: i. Introduction to shoreline management ii. State-of-the-art for shore protection interventions inside and outside Europe iii. Presentation of a comprehensive database of coastal defence techniques iv. Presentation of a world map illustrating the location of innovative techniques v. Detailed description of the selected case studies vi. Results from the case studies: .. policy of intervention .. measures adopted .. limitations .. analysis of key factors of success or failure related to each of the techniques inventoried .. cost-benefit analysis vii. Conclusions viii. Recommendations ix. References x. Appendix: Glossary of terminology relating to coastal defence techniquesMessin

Submerged depositional terraces in the Gulf of Policastro (Southern Tyrrhenian sea, Italy).

I processi morfologici e sedimentari che si attuano nella porzione settentrionale e meridionale del Golfo di Poicastro si differenziano grazie all’assetto strutturale del Golfo che non è indicativo di un “tipico margine passivo”. Infatti, il sistema piattaforma - scarpata che borda il bacino di Sapri, nella porzione settentrionale, è caratterizzato da un marcato controllo strutturale e risulta essere sin dalla sua impostazione in evidente erosione. Invece, il controllo strutturale è meno evidente nel settore meridionale, che presenta gli effetti di processi di progradazione e aggradazione, facilitati dal significativo apporto clastico dei corsi d’acqua (es. fiumare) che dissecano il margine della Calabria settentrionale. Ciononostante, sebbene i contesti morfostrutturali attuali e verosimilmente di 18.000 anni fa della porzione settentrionale e di quella meridonale del Golfo di Policastro siano differenti, i corpi sedimentari sommersi con geometria esterna terrazzata, presentando quasi le stesse caratteristiche, hanno probabilmente la medesima genesi. La loro origine sembra sia da ascrivere a processi sedimentari avvenuti nel corso dello stazionamento basso del livello del mare durante l'ultimo episodio glaciale. In tale occasione il mare si ritirò sino all'attuale isobata dei -110/-120 m nel Margine Tirrenico Orientale determinando lo spostamento dell'antica linea di riva sino a profondità inferiori al ciglio attuale della piattaforma, favorendo così la genesi di depositi di spiaggia regressivi progradanti. In assenza di apporti sedimentari veniva favorita la deposizione di depositi progradazionali di regressione "forzata", costituiti da depositi costieri gradualmente più recenti verso mare ed in generale ben preservati sui margini continentali, che presentano nel settore indagato caratteristiche analoghe a quelli individuati lungo altri margini continentali

Late Quaternary morphological evolution of a continental margin based on emerged and submerged morphostructural features: the south-eastern Tyrrenian margin (Italy).

Identification of physiographic elements along the Tyrrhenian margin between Cape Palinuro and Cape Bonifati was carried out by interpretation of acoustic profiles. These elements are the expression of both Plio-Quaternary extensional tectonism (related to the subsidence of the Tyrrhenian Sea) and Appennine chain uplift (with its late compressive phenomena). All these tectonic events, which took place until recent times, produced northward and seaward stair-like blocks as well as relief and basin systems. The shelf-slope system bordering the Sapri basin, with high structural control, underwent clearcut erosion since its genesis, as testified by gravitative processes producing slumps and turbiditic flows. These sediments are collected in the basin which represents the gravitative base-level for this part of the shelf-slope system. In contrast, the southern sector of the investigated margin, where structural control is less evident, clearly indicates progradation and aggradation, facilitated by abundant elastic supplies from the rivers cutting the northern Calabrian margin

Morphology, genesis and evolution of rockpools along Italian coasts

Observation of thirteen morphotypes of rockpool falling into five different categories and some forms with intermediate features allowed a genetic-morphological classification to be proposed. The surveyed rockpools may be found in any resistant substrate, in both emerged and submerged environments, and show a general evolutionary trend towards spindle-shaped geometries. Frequent phenomena of piracy, producing rejuvenated forms and/or large, complex rockpools are observed in different morphotypes. Bio-erosion, bio-constructor micro-organism action, salt precipitation, marine and meteoric waters physico-chemical erosion, mechanical erosion by waves, climatic conditions, and rocky substrate characteristics greatly influence the development of rockpools. In addition to currently evolving forms, fossil forms may also be observed on Pleistocene marine terraces, both emerged or submerged, sometimes remodelled or infilled by sediments