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In the Big Data era, the amount and complexity of astronomical data more and more often prevents the scientist from locally store and process her/his data. As a consequence, the geographically distributed approach to data archiving and processing is rapidly becoming a requisite. To fulfill this need, we are realizing a prototype of Science Gateway (SG) for the Italian radio telescopes. The huge amount of significantly complex and resource-demanding datasets delivered by the Italian radio telescopes and the variety of use cases from the different observing modes represent an ideal test bed for the implementation and verification of a SG environment where the scientists can exploit, manage and analyse data. To this aim, we are exploiting our previous experience in the realization of a geographically-distributed radio data archive and processing tools as well as in the design of SG prototypes. Such a coordinated approach and harmonization of resources will maximize the return for the Italian observing facilities and, moreover, will match the requirements of the international community for a state-of-the-art, highly-performant environment in which to conduct successful science.

We present the status of the Sardinia Radio Telescope (SRT) and its forthcoming update planned in the next few years. The post-process scenario of the upgraded infrastructure will allow the national and international scientific community to use the SRT for the study of the Universe at high radio frequencies (up to 116 GHz), both in single dish and in interferometric mode. A telescope like SRT, operating at high frequencies, represents a unique resource for the scientific community. The telescope will be ideal for mapping quickly and with relatively high angular resolution extended radio emissions characterized by low surface brightness. It will also be essential for spectroscopic and polarimetric studies of both Galactic and extragalactic radio sources. With the use of the interferometric technique, SRT and the other Italian antennas (Medicina and Noto) will operate within the national and international radiotelescope network, allowing astronomers to obtain images of radio sources at very high angular resolution.

We present the first detection of atomic emission lines from the atmosphere of an exoplanet. We detect neutral iron lines from the day-side of KELT-9b (Teq $\sim$ 4, 000 K). We combined thousands of spectrally resolved lines observed during one night with the HARPS-N spectrograph (R $\sim$ 115, 000), mounted at the Telescopio Nazionale Galileo. We introduce a novel statistical approach to extract the planetary parameters from the binary mask cross-correlation analysis. We also adapt the concept of contribution function to the context of high spectral resolution observations, to identify the location in the planetary atmosphere where the detected emission originates. The average planetary line profile intersected by a stellar G2 binary mask was found in emission with a contrast of 84 $\pm$ 14 ppm relative to the planetary plus stellar continuum (40 $\pm$ 5$\%$ relative to the planetary continuum only). This result unambiguously indicates the presence of an atmospheric thermal inversion. Finally, assuming a modelled temperature profile previously published (Lothringer et al. 2018), we show that an iron abundance consistent with a few times the stellar value explains the data well. In this scenario, the iron emission originates at the $10^{-3}$-$10^{-5}$ bar level., Comment: Accepted for publication on ApJL; 19 pages, 4 figures, 3 tables

With the advent of the 2020 Radio Astronomy Telescopes era, the amount and format of the radioastronomical data is becoming a massive and performance-critical challenge. Such an evolution of data models and data formats require new data archiving techniques that allow massive and fast storage of data that are at the same time also efficiently processed. A useful expertise for efficient archiviation has been obtained through data archiving of Medicina and Noto Radio Telescopes. The presented archival infrastructure named the Radio Archive stores and handles various formats, such as FITS, MBFITS, and VLBI’s XML, which includes description and ancillary files. The modeling and architecture of the archive fulfill all the requirements of both data persistence and easy data discovery and exploitation. The presented archive already complies with the Virtual Observatory directives, therefore future service implementations will also be VO compliant. This article presents the Radio Archive services and tools, from the data acquisition to the end-user data utilization.

The VIALACTEA project brings to a common forum the major new-generation surveys of the Milky Way Galactic Plane from 1μm to the radio, both in thermal continuum and in atomic and molecular lines, to attack in a systematic way the characterization of the Milky Way as a star formation engine. Images, catalogues, spectroscopic datacubes and radiative transfer models of the Spectral Energy Distributions (SEDs) of sites of star formation have been incorporated and indexed in the VIALACTEA Knowledge Base (VLKB). The VLKB consists of a combination of a relational database where the VIALACTEA data and metadata are homogenised and stored, and a filesystem-based stored information. This infrastructure allowed, among others, the generation of extensive catalogue for compact sources and extended structures in the Galactic Plane, the implementation of data-mining algorithms for the band-merging of multiwavelength data and expert systems for the automated analysis of molecular line surveys to extract critical kinematical information and derive distances using Galaxy rotation curves and new 3D extinction maps. A new VIALACTEA 3D Visual Analytics interface has been developed that provides integrated access and analysis of continuum and spectroscopic images together with catalogue data directly interfacing with the VLKB.

One basic system requirement for the SKA Project is aimed to providing both a rolled-up and a drilled-down view of the Operational (Health) Status, as well as the State, for each Element. The first one is a performance indicator that must be properly structured in order an operator can understand it. The second one is a logic enumerative that has to contain at least the following values: start-up, shutdown, standby and operational. In this paper an aggregation algorithm, defined for the Health Status of the SKA Telescope Manager (TM) but abstract enough in order to be extended to a generic complex system, is analyzed in terms of the three main indications it has to provide: fully operating, degraded performance, faulty. The analysis shows that the distinction among critical and non-critical components, along with their state and weight on the overall system, is enough to completely achieve a rolled-up view of the system. System architecture only affects the weights, which are the result of a dependability analysis initially performed on the system itself. The aggregation can be applied to selected subsets of components, so providing hints for a drilling-down of the monitoring data, when this is necessary. Finally, using the algorithm to aggregate the states essentially fails: a different approach based on logic relationships will have to be adopted in order to manage states, but to this purpose an important role can be played by the aggregated health status.

The TANGO controls framework community has put a lot of effort in creating the HDB++ software system that is an high performance, event-driven archiving system. Its design allows storing data into traditional database management systems such as MySQL as well as NoSQL database such as Apache Cassandra. The architecture allow also to easily extend it to other noSql database like, for instance, ELK. This paper describes the step needed to extend the HDB++ and explore the possibilities to use the ELK technology in term of analysis being enabled and tools provided.

Adopting the recommendations for the control room obtained by a user-centered design approach for the Square Kilometer Array (SKA), the following characteristics for the SKA Graphical User Interface (GUI) have been identified: scalability, integrated tools, extendability and completeness. The lack of one or more of these characteristics could lead to usability problems like low user’s efficiency, high error rate, high user’s mental load and user’s frustration. In this paper one of the most recent web technologies that enable the user-centered design are analyzed. TangoWebApp, a pluggable web platform integrated with TANGO Control REST API, appears very suitable also taking into account the adoption of TANGO as the SKA control framework. Starting from a SKA Telescope Manager (TM) Services use case, a prototype has been developed composed by a series of TANGO WebApp plugins that allow the operator to correctly and efficiently complete the tasks of the scenario. Some of the plugins, in particular, have been developed to extend the functionalities of the TANGO WebApp itself to make it fully compliant with the User Centered Design. As a result of this work, the TangoWebapp proved itself not only fully compliant with the User Centered Design, but also flexible enough to add functionalities in the form of properly developed plugins. These characteristics of the TangoWebapp, together with its unique feature to be integrated into TANGO, make it a good candidate to be the SKA GUI platform.

Context. Identification of planetary companions of giant stars is made difficult because of the astrophysical noise, that may produce radial velocity (RV) variations similar to those induced by a companion. On the other hand any stellar signal is wavelength dependent, while signals due to a companion are achromatic. Aims. Our goal is to determine the origin of the Doppler periodic variations observed in the thick disk K giant star TYC 4282-605-1 by HARPS-N at the Telescopio Nazionale Galileo (TNG) and verify if they can be due to the presence of a substellar companion. Methods. Several methods have been used to exclude the stellar origin of the observed signal including detailed analysis of activity indicators and bisector and the analysis of the photometric light curve. Finally we have conducted an observational campaign to monitor the near infrared (NIR) RV with GIANO at the TNG in order to verify whether the NIR amplitude variations are comparable with those observed in the visible. Results. Both optical and NIR RVs show consistent variations with a period at 101 days and similar amplitude, pointing to the presence of a companion orbiting the target. The main orbital properties obtained for our giant star with a derived mass of M=0.97+-0.03M_sun are M_Psini=10.78+-0.12MJ;P=101.54+-0.05days;e=0.28+-0.01 and a=0.422+-0.009AU. The chemical analysis shows a significant enrichment in the abundance of Nai, Mgi, Ali and S i while the rest of analyzed elements are consistent with the solar value demonstrating that the chemical composition corresponds with an old K giant (age = 10.1 Gyr) belonging to local thick disk. Conclusions. We conclude that the substellar companion hypothesis for this K giant is the best explanation for the observed periodic RV variation. This study also shows the high potential of multi-wavelength RV observations for the validation of planet candidates., Comment: Accepted in Journal reference A&A 14/06/2017

We present observations of the interacting transient SN 2009ip, from the start of the outburst in October 2012 until the end of the 2012 observing season. The transient reached a peak of $M_V$=-17.7 mag before fading rapidly, with a total integrated luminosity of 1.9$\times10^{49}$ erg over the period of August-December 2012. The optical and near infrared spectra are dominated by narrow emission lines, signaling a dense circumstellar environment, together with multiple components of broad emission and absorption in H and He at velocities between 0.5-1.2$\times10^4$ km s$^{-1}$\. We see no evidence for nucleosynthesized material in SN 2009ip, even in late-time pseudo-nebular spectra. We set a limit of $, Comment: 28 pages, submitted to MNRAS. Abstract abridged for arXiv

The SKA Telescope Manager (TM) is the core package of the SKA Telescope: it is aimed at scheduling observations, controlling their execution, monitoring the telescope health status, diagnosing and fixing its faults and so on. To do that, TM directly interfaces with the Local Monitoring and Control systems (LMCs) of the various SKA Elements (e.g. Dishes, Low-Frequency Aperture Array, etc.), exchanging commands and data with each of them. TM in turn needs to be monitored and controlled, in order its continuous and proper operation - and therefore that of the whole SKA Telescope - is ensured. It appears indeed that, while the unavailability of one or more instances of any other SKA element should result only in a degraded operation for the whole telescope, a problem in TM could cause a complete stop of any operation. In addition to this higher responsibility, a local monitoring and control system for TM has to collect and display logging data directly to operators, perform lifecycle management of TM applications and directly deal - when possible - with management of TM faults (which also includes a direct handling of TM status and performance data). In this paper, the peculiarities presented by the TM monitoring and control and the consequences they have on the design of a related LMC system are addressed and discussed.

Astrophysical data provider organizations that host web based interfaces to provide access to data resources have to cope with possible changes in data management that imply partial rewrites of web applications. To avoid doing this manually it was decided to develop a dynamically configurable Java EE web application that can set itself up reading needed information from configuration files. Specification of what information the astronomical archive database has to expose is managed using the TAP SCHEMA schema from the IVOA TAP recommendation, that can be edited using a graphical interface. When configuration steps are done the tool will build a war file to allow easy deployment of the application.

Radio Astronomical Data models are becoming very complex since the huge possible range of instrumental configurations available with the modern Radio Telescopes. What in the past was the last frontiers of data formats in terms of efficiency and flexibility is now evolving with new strategies and methodologies enabling the persistence of a very complex, hierarchical and multi-purpose information. Such an evolution of data models and data formats require new data archiving techniques in order to guarantee data preservation following the directives of Open Archival Information System and the International Virtual Observatory Alliance for data sharing and publication. Currently, various formats (FITS, MBFITS, VLBI's XML description files and ancillary files) of data acquired with the Medicina and Noto Radio Telescopes can be stored and handled by a common Radio Archive, that is planned to be released to the (inter)national community by the end of 2016. This state-of-the-art archiving system for radio astronomical data aims at delegating as much as possible to the software setting how and where the descriptors (metadata) are saved, while the users perform user-friendly queries translated by the web interface into complex interrogations on the database to retrieve data. In such a way, the Archive is ready to be Virtual Observatory compliant and as much as possible user-friendly.

In order to understand the observed physical and orbital diversity of extrasolar planetary systems, a full investigation of these objects and of their host stars is necessary. Within this field, one of the main purposes of the GAPS observing project with HARPS-N@TNG is to provide a more detailed characterisation of already known systems. In this framework we monitored the star, hosting two giant planets, HD108874, with HARPS-N for three years in order to refine the orbits, to improve the dynamical study and to search for additional low-mass planets in close orbits. We subtracted the radial velocity (RV) signal due to the known outer planets, finding a clear modulation of 40.2 d period. We analysed the correlation between RV residuals and the activity indicators and modelled the magnetic activity with a dedicated code. Our analysis suggests that the 40.2 d periodicity is a signature of the rotation period of the star. A refined orbital solution is provided, revealing that the system is close to a mean motion resonance of about 9:2, in a stable configuration over 1 Gyr. Stable orbits for low-mass planets are limited to regions very close to the star or far from it. Our data exclude super-Earths with Msin i \gtrsim 5 M_Earth within 0.4 AU and objects with Msin i \gtrsim 2 M_Earth with orbital periods of a few days. Finally we put constraints on the habitable zone of the system, assuming the presence of an exomoon orbiting the inner giant planet., Comment: 10 pages; 11 figures; A&A Accepted

Stellar activity is the ultimate source of radial-velocity (RV) noise in the search for Earth-mass planets orbiting late-type main-sequence stars. We analyse the performance of four different indicators and the chromospheric index $\log R'_{\rm HK}$ in detecting RV variations induced by stellar activity in 15 slowly rotating ($v\sin i \leq 5$ km/s), weakly active ($\log R'_{\rm HK} \leq -4.95$) solar-like stars observed with the high-resolution spectrograph HARPS-N. We consider indicators of the asymmetry of the cross-correlation function (CCF) between the stellar spectrum and the binary weighted line mask used to compute the RV, that is the bisector inverse span (BIS), $\Delta V$, and a new indicator $V_{\rm asy(mod)}$ together with the full width at half maximum (FWHM) of the CCF. We present methods to evaluate the uncertainties of the CCF indicators and apply a kernel regression (KR) between the RV, the time, and each of the indicators to study their capability of reproducing the RV variations induced by stellar activity. The considered indicators together with the KR prove to be useful to detect activity-induced RV variations in $47 \pm 18$ percent of the stars over a two-year time span when a significance (two-sided p-value) threshold of one percent is adopted. In those cases, KR reduces the standard deviation of the RV time series by a factor of approximately two. The BIS, the FWHM, and the newly introduced $V_{\rm asy(mod)}$ are the best indicators, being useful in $27 \pm 13$, $13 \pm 9$, and $13 \pm 9$ percent of the cases, respectively. The relatively limited performances of the activity indicators are related to the very low activity level and $v\sin i$ of the considered stars. For the application of our approach to sun-like stars, a spectral resolution of at least $10^5$ and highly stabilized spectrographs are recommended., Comment: 15 pages, 6 figures, 5 tables, one Appendix, accepted to Astronomy and Astrophysics

Deep multicolour surveys are the main tool to explore the formation and evolution of the faint galaxies which are beyond the spectroscopic limit with the present technology. The photometric properties of these faint galaxies are usually compared with current renditions of semianalytical models to provide constraints on the fundamental physical processes involved in galaxy formation and evolution, namely the mass assembly and the star formation. Galaxy counts over large sky areas in the near-UV band are important because they are difficult to obtain given the low efficiency of near-UV instrumentation, even at 8m class telescopes. A large instrumental field of view helps in minimizing the biases due to the cosmic variance. We have obtained deep images in the 360nm U band provided by the blue channel of the Large Binocular Camera at the prime focus of the Large Binocular Telescope. We have derived over an area of ~0.4 sq. deg. the galaxy number counts down to U=27 in the Vega system (corresponding to U=27.86 in the AB system) at a completeness level of 30% reaching the faintest current limit for this wavelength and sky area. The shape of the galaxy counts in the U band can be described by a double power-law, the bright side being consistent with the shape of shallower surveys of comparable or greater areas. The slope bends over significantly at U>23.5 ensuring the convergence of the contribution by star forming galaxies to the EBL in the near-UV band to a value which is more than 70% of the most recent upper limits derived for this band. We have jointly compared our near-UV and K band counts collected from the literature with few selected hierarchical CDM models emphasizing critical issues in the physical description of the galaxy formation and evolution., Accepted for publication in A&A. Uses aa.cls, 9 pages, 4 figures. Citations updated

We used a proper combination of multiband high-resolution and wide field multi-wavelength observations collected at three different telescopes (HST, LBT and CFHT) to probe Blue Straggler Star (BSS) populations in the globular cluster M53. Almost 200 BSS have been identified over the entire cluster extension. The radial distribution of these stars has been found to be bimodal (similarly to that of several other clusters) with a prominent dip at ~60'' (~2 r_c) from the cluster center. This value turns out to be a factor of two smaller than the radius of avoidance (r_avoid, the radius within which all the stars of ~1.2 M_sun have sunk to the core because of dynamical friction effects in an Hubble time). While in most of the clusters with a bimodal BSS radial distribution, r_avoid has been found to be located in the region of the observed minimum, this is the second case (after NGC6388) where this discrepancy is noted. This evidence suggests that in a few clusters the dynamical friction seems to be somehow less efficient than expected. We have also used this data base to construct the radial star density profile of the cluster: this is the most extended and accurate radial profile ever published for this cluster, including detailed star counts in the very inner region. The star density profile is reproduced by a standard King Model with an extended core (~25'') and a modest value of the concentration parameter (c=1.58). A deviation from the model is noted in the most external region of the cluster (at r>6.5' from the center). This feature needs to be further investigated in order to address the possible presence of a tidal tail in this cluster.

We present the characteristics and some early scientific results of the first instrument at the Large Binocular Telescope (LBT), the Large Binocular Camera (LBC). Each LBT telescope unit will be equipped with similar prime focus cameras. The blue channel is optimized for imaging in the UV-B bands and the red channel for imaging in the VRIz bands. The corrected field-of-view of each camera is approximately 30 arcminutes in diameter, and the chip area is equivalent to a 23x23 arcmin2 field. In this paper we also present the commissioning results of the blue channel. The scientific and technical performance of the blue channel was assessed by measurement of the astrometric distortion, flat fielding, ghosts, and photometric calibrations. These measurements were then used as input to a data reduction pipeline applied to science commissioning data. The measurements completed during commissioning show that the technical performance of the blue channel is in agreement with original expectations. Since the red camera is very similar to the blue one we expect similar performance from the commissioning that will be performed in the following months in binocular configuration. Using deep UV image, acquired during the commissioning of the blue camera, we derived faint UV galaxy-counts in a ~500 sq. arcmin. sky area to U(Vega)=26.5. These galaxy counts imply that the blue camera is the most powerful UV imager presently available and in the near future in terms of depth and extent of the field-of-view. We emphasize the potential of the blue camera to increase the robustness of the UGR multicolour selection of Lyman break galaxies at redshift z~3., Comment: Accepted for publication in A&A. Uses aa.cls, 10 pages, 10 figures. Zero points changed in Table 2

We present a deep, wide-field photometric survey of the newly discovered Hercules dwarf spheroidal galaxy (dSph), based on data from the Large Binocular Telescope. Images in B, V, and r were obtained with the Large Binocular Camera covering a 23' × 23' field of view to a magnitude of ~25.5 (5 σ). This permitted the construction of color-magnitude diagrams that reach approximately 1.5 mag below the Hercules main-sequence turnoff. Three-filter photometry allowed us to preferentially select probable Hercules member stars and to examine the structure of this system at a previously unattained level. We find that the Hercules dwarf is highly elongated (3 : 1), considerably more so than any other dSph satellite of the Milky Way, except the disrupting Sagittarius dwarf. Although we cannot rule out that the unusual structure is intrinsic to Hercules as an equilibrium system, our results suggest tidal disruption as a likely cause of this highly elliptical structure. Given the relatively large galactocentric distance of this system (132 ± 12 kpc), signs of tidal disruption would require the Hercules dwarf to be on a highly eccentric orbit around the Milky Way.

PLANCK, the ESA satellite aimed at mapping the microwave sky through two complete sky surveys, will fly in 2007. It is an extremely demanding space mission in terms of computing power and data storage. PLANCK simulations mimic the whole mission starting from a virtual sky (ideal or contaminated by introducing several noise sources). Their main goal is the validation of the acquisition and reduction procedure that will be used to build the final scientific data during the operative phase of the mission. The GRID technology seems to be a promising answer to data storage and processing needs of the satellite. In the framework of the EGEE grid infrastructure, we managed to run a number of experiments aimed at designing and defining an application specific environment for the simulation software and data sharing. Our successful experiments demonstrate that the "gridification" of Planck pipelines is not only possible but even extremely convenient in terms of data processing speed and data sharing.

We carried out a Bayesian homogeneous determination of the orbital parameters of 231 transiting giant planets (TGPs) that are alone or have distant companions; we employed DE-MCMC methods to analyse radial-velocity (RV) data from the literature and 782 new high-accuracy RVs obtained with the HARPS-N spectrograph for 45 systems over 3 years. Our work yields the largest sample of systems with a transiting giant exoplanet and coherently determined orbital, planetary, and stellar parameters. We found that the orbital parameters of TGPs in non-compact planetary systems are clearly shaped by tides raised by their host stars. Indeed, the most eccentric planets have relatively large orbital separations and/or high mass ratios, as expected from the equilibrium tide theory. This feature would be the outcome of high-eccentricity migration (HEM). The distribution of $��=a/a_R$, where $a$ and $a_R$ are the semi-major axis and the Roche limit, for well-determined circular orbits peaks at 2.5; this also agrees with expectations from the HEM. The few planets of our sample with circular orbits and $��>5$ values may have migrated through disc-planet interactions instead of HEM. By comparing circularisation times with stellar ages, we found that hot Jupiters with $a < 0.05$ au have modified tidal quality factors $10^{5} < Q'_p < 10^{9}$, and that stellar $Q'_s > 10^{6}-10^{7}$ are required to explain the presence of eccentric planets at the same orbital distance. As a by-product of our analysis, we detected a non-zero eccentricity for HAT-P-29; we determined that five planets that were previously regarded to have hints of non-zero eccentricity have circular orbits or undetermined eccentricities; we unveiled curvatures caused by distant companions in the RV time series of HAT-P-2, HAT-P-22, and HAT-P-29; and we revised the planetary parameters of CoRoT-1b., 44 pages (16 pages of main text and figures), 11 figures, 5 longtables, published in Astronomy and Astrophysics, Volume 602, A107 (2017). Tables with new HARPS-N and TRES radial-velocity data (Tables 1 and 2), stellar parameters (Table 7), orbital parameters and RV jitter (Table 8), and planet physical parameters (Table 9) are available as ancillary files (sidebar on the right)

The International Virtual Observatory Alliance (IVOA) has produced many standards and recommendations whose aim is to generate an architecture that starts from astrophysical resources, in a general sense, and ends up in deployed consumable services (that are themselves astrophysical resources). Focusing on the Data Access Layer (DAL) system architecture, that these standards define, in the last years a web based application has been developed and maintained at INAF-OATs IA2 (Italian National institute for Astrophysics – Astronomical Observatory of Trieste, Italian center of Astronomical Archives) to try to deploy and manage multiple VO (Virtual Observatory) services in a uniform way: VO-Dance. However a set of criticalities have arisen since when the VO-Dance idea has been produced, plus some major changes underwent and are undergoing at the IVOA DAL layer (and related standards): this urged IA2 to identify a new solution for its own service layer. Keeping on the basic ideas from VO-Dance (simple service configuration, service instantiation at call time and modularity) while switching to different software technologies (e.g. dismissing Java Reflection in favour of Enterprise Java Bean, EJB, based solution), the new solution has been sketched out and tested for feasibility. Here we present the results originating from this test study. The main constraints for this new project come from various fields. A better homogenized solution rising from IVOA DAL standards: for example the new DALI (Data Access Layer Interface) specification that acts as a common interface system for previous and oncoming access protocols. The need for a modular system where each component is based upon a single VO specification allowing services to rely on common capabilities instead of homogenizing them inside service components directly. The search for a scalable system that takes advantage from distributed systems. The constraints find answer in the adopted solutions hereafter sketched. The development of the new system using Java Enterprise technologies can better benefit from existing libraries to build up the single tokens implementing the IVOA standards. Each component can be built from single standards and each deployed service (i.e. service components instantiations) can consume the other components' exposed methods and services without the need of homogenizing them in dedicated libraries. Scalability can be achieved in an easier way by deploying components or sets of services on a distributed environment and using JNDI (Java Naming and Directory Interface) and RMI (Remote Method Invocation) technologies. Single service configuration will not be significantly different from the VO-Dance solution given that Java class instantiation that benefited from Java Reflection will only be moved to Java EJB pooling (and not, e.g. embedded in bundles for subsequent deployment).

The STARnet Gateway Federation is a unique example of a federated network of science gateways based on WS-PGRADE/gUSE technologies, and explicitly designed and tuned to the needs of the astronomical and astrophysical (A&A) community in Europe. The use of a federated gateway infrastructure allows scientists to explore new collaboration opportunities and advancing the scientific research activity within A&A. STARnet Gateways share a common authentication system, a distributed computing infrastructure, data archives, portlets, and workflow repositories. Building upon these technologies, a number of challenging applications from different A&A domains have been successfully prototyped and tested.

The spectral classification of stars in galaxies is a method of studying their stellar content. In particular, the distribution of spectral types in the stellar systems is a powerful diagnostic for the estimation of their composition, age and evolutionary state. The observational materials mainly used are spectral plates obtained with Schmidt telescopes. Such plates contain, generally, thousands of spectra. There are prism-plate libraries and digitized databases in several astronomical centres that can be fully exploited only with automated processing. Such a system for automated processing of stellar spectra on digitized objective-prism plates is presented. It is developed as a context under the MIDAS environment and provides tools for digital preprocessing of the images (rotating, correcting the tilt, calibration, etc.), for interactive and automated detection of the spectra, for spectra extraction as one-dimensional scans, and finally, for automated classification. Here we particularly present...

The telescopes of the new generation allow an archive to be built as a section of data management; nevertheless, careful planning is needed and data handling needs to be designed together with the control system of the telescope itself, both for space-borne and for ground-based facilities. Simulations are essential to understand how observations will be archived, and to build and test an archiving system capable of dealing efficiently with the expected data flow.

A key tracer of the elusive progenitor systems of Type Ia supernovae (SNe Ia) is the detection of narrow blueshifted time-varying Na I D absorption lines, interpreted as evidence of circumstellar material (CSM) surrounding the progenitor system. The origin of this material is controversial, but the simplest explanation is that it results from previous mass loss in a system containing a white dwarf and a non-degenerate companion star. We present new single-epoch intermediate-resolution spectra of 17 low-redshift SNe Ia taken with XShooter on the ESO Very Large Telescope. Combining this sample with events from the literature, we confirm an excess (~20 per cent) of SNe Ia displaying blueshifted narrow Na I D absorption features compared to non-blueshifted Na I D features. The host galaxies of SNe Ia displaying blueshifted absorption profiles are skewed towards later-type galaxies, compared to SNe Ia that show no Na I D absorption, and SNe Ia displaying blueshifted narrow Na I D absorption features have broader light curves. The strength of the Na I D absorption is stronger in SNe Ia displaying blueshifted Na I D absorption features than those without blueshifted features, and the strength of the blueshifted Na I D is correlated with the B-V colour of the SN at maximum light. This strongly suggests the absorbing material is local to the SN. In the context of the progenitor systems of SNe Ia, we discuss the significance of these findings and other recent observational evidence on the nature of SN Ia progenitors. We present a summary that suggests there are at least two distinct populations of normal, cosmologically useful SNe Ia., Comment: 19 pages, 9 figures, accepted for publication in MNRAS

Italian center for Astronomical Archives (IA2, http://ia2.oats.inaf.it) is a national infrastructure project of the Italian National Institute for Astrophysics (Istituto Nazionale di AstroFisica, INAF) that provides services for the astronomical community. Besides data hosting for the Large Binocular Telescope (LBT) Corporation, the Galileo National Telescope (Telescopio Nazionale Galileo, TNG) Consortium and other telescopes and instruments, IA2 offers proprietary and public data access through user portals (both developed and mirrored) and deploys resources complying the Virtual Observatory (VO) standards. Archiving systems and web interfaces are developed to be extremely flexible about adding new instruments from other telescopes. VO resources publishing, along with data access portals, implements the International Virtual Observatory Alliance (IVOA) protocols providing astronomers with new ways of analyzing data. Given the large variety of data flavours and IVOA standards, the need for tools to easily accomplish data ingestion and data publishing arises. This paper describes the VO-Dance tool, that IA2 started developing to address VO resources publishing in a dynamical way from already existent database tables or views. The tool consists in a Java web application, potentially DBMS and platform independent, that stores internally the services' metadata and information, exposes restful endpoints to accept VO queries for these services and dynamically translates calls to these endpoints to SQL queries coherent with the published table or view. In response to the call VO-Dance translates back the database answer in a VO compliant way.

In this document, an approach to the development of WWW-accessible astronomical archives and databases is described, which can easily be extended also to other disciplines. The architecture is based on a set of servers running at the archive site, each performing a specialized task: accessing an SQL-based DBMS, retrieving and downlinking 1-D or 2-D data (measurements), displaying quicklook data, or plotting the results of a query to the database. All of the information on the user interface is dynamically stored in the database, allowing the pages to be prepared on-the-fly; no additional software needs to be run on the user’s computer. A WWW-accessible test astronomical archive, containing both 2-D (images) and 1-D (spectra) data, and having NCSA/Mosaic as an interface is described as an example of successful application of the above concepts.

Since the very beginning of 2008, the Large Binocular Telescope (LBT) is officially equipped with it's first binocular instrument ready for science observations: the Large Binocular Camera (LBC). This is a double CCD imager, installed at the prime focus stations of the two 8.4m telescopes of LBT, able to obtain deep and wide field images in the whole optical spectrum from UV to NIR wavelengths. We present here the overall architecture of the instrument, a brief hardware review of the two imagers and notes how observations are carried on. At the end we report preliminary results on the performances of the instrument along with some images obtained during the first months of observations in binocular mode.

The Large Binocular Telescope is currently equipped with a couple of wide field Prime Focus. The two cameras are optimized for, respectively, the blue and the red portion of the visible spectrum. The history of this project is here sketched up and the current status is shown. The Blue channel is currently working onboard the telescope and provided what has been named the first-light of the telescope in single eye configuration.

The federation of heterogeneous large astronomical databases foreseen in the framework of the AVO and NVO projects will pose unprecedented data mining and visualization problems which may find a rather natural and user friendly answer in artificial intelligence (A.I.) tools based on neural networks, fuzzy-C sets or genetic algorithms. We shortly describe some tools implemented by the AstroNeural collaboration (Napoli-Salerno) aimed to perform complex tasks such as, for instance, unsupervised and supervised clustering and time series analysis. Two very different applications to the analysis of photometric redshifts of galaxies in the Sloan Early Data Release and to the telemetry of the TNG (telescopio nazionale Galileo) are also discussed as template cases.

The Prime Focus for the Large Binocular Telescope are a couple of Prime Focus stations each equipped with four 4kx2k CCDs and a six lenses corrector with an aspheric surface and the first lens as large as roughly 800mm in diameter. These cameras will cover almost half degree of Field of View on 8m-class telescopes with unprecedented velocity of F/1.4. The two units are optimized for the Red and Blue portions of the visible wavelength and additionally an extension to J and H bands is foreseen. An overview of the project, including the optomechanics, the cryogenics, the electronics, and the software is given along with a preliminary account of lessons learned and on how much the second unit, the Red one, the schedule of which is shifted with respect to the Blue one by several months, will take advantage from the experience gained in the Blue unit assembly and integration.

In recent years great efforts have been spent in the astronomical community to allow a global and seamless electronic access to distributed astronomical data repositories, and to enable scientific analysis on them. A system capable of providing these services over distributed databases and computer resources is called a Virtual Observatory (VO). VOs are still in the study phase, with many projects around the world now delivering their first prototype implementations. In the meanwhile grid technologies have started to emerge and consolidate and are now expected to play a fundamental role in the development of Astrophysical Virtual Observatories. We report here about our activities aimed at integrating in the grid environment a system, developed in Padova, specifically designed for accessing very large astronomical catalogues. We evaluated several possible solutions, including the use of a tool for accessing databases developed by the European Data Grid (EDG) project, but finally we decided to adopt a web services based architecture, retaining the security infrastructure provided by the EDG software. We plan to evolve towards an implementation fully compliant with the latest Open Grid Service Architecture specification, but without loosing compatibility with the grid middleware adopted in our project. This work is being conducted in the framework of Grid.it, a project, funded by the Italian Ministry for Education, University and Research, aimed at studying a grid infrastructure for scientific research in Italy and developing specific software tools and protype applications that run on it. This catalogue access system will eventually become one of the first building blocks of the Italian Virtual Observatory, currently under development in the framework of a closely-related project, named DRACO. To this end, starting from the design phase of our system, and where applicable, we adopted the standards set forth by the International Virtual Observatory Alliance (IVOA).

The Large Binocular Camera (LBC) is the double optical imager that will be installed at the prime foci of the Large Binocular Telescope (2x8.4 m). Four Italian observatories are cooperating in this project: Rome (CCD Camera), Arcetri-Padua (Optical Corrector) and Trieste (Software). LBC is composed by two separated large field (27 arcmin FOV) cameras, one optimized for the UBV bands and the second for the VRIZ bands. An optical corrector balances the aberrations induced by the fast (F#=1.14) parabolic primary mirror of LBT, assuring that the 80% of the PSF encircled energy falls inside one pixel for more of the 90% of the field. Each corrector uses six lenses with the first having a diameter of 80cm and the third with an aspherical surface. Two filter wheels allow the use of 8 filters. The two channels have similar optical designs satisfying the same requirements, but differ in the lens glasses: fused silica for the "blue" arm and BK7 for the "red" one. The two focal plane cameras use an array of four 4290 chips (4.5x2 K) provided by Marconi optimized for the maximum quantum efficiency (85%) in each channel. The sampling is 0.23 arcseconds/pixel. The arrays are cooled by LN2 cryostats assuring 24 hours of operation. Here we present a description of the project and its current status including a report about the Blue camera and its laboratory tests. This instrument is planned to be the first light instrument of LBT.

The Italian National "Galileo" Telescope (Telescopio Nazionale "Galileo" - TNG) is a 3.5m telescope located at La Palma, in the Canary islands, which has seen first light in 1998. Available TNG subsystems include four first-generation instruments, plus adaptive optics, meteo and seeing towers; the control and data handling systems are tightly coupled allowing a smooth data flow while preserving integrity. As a part of the data handling systems, the production of a local "Archive at the Telescope" (AaT) is included, and the production of database tables and hard media for the TNG Long-Term Archive (LTA) is supported. The implementation of a LTA prototype has been recently terminated, and the implementation of its operational version is being planned by the Italian National Institute for Astrophysics (INAF). A description of the AaT and prototype LTA systems are given, including their data handling/archiving and data retrieval capabilities. A discussion of system features and lessons learned is also included, with particular reference to the issues of completeness and data quality. These issues are of particular importance in the perspective of the preparation of a national facility for the archives of data from ground-based telescopes, and its possible inclusion as a data provider in the Virtual Observatory framework.

The large Binocular Telescope is currently in the pre- erection phase. The instrument has been already funded and its first-light is expected shortly after that of the LBT. Given the peculiarity of the telescope optics we designed tow prime focus cameras with two five-lens refractive correctors, optimized in the blue-side and red-side of the visible spectrum respectively. This independent coating. Detectors also reflect this choice, being optimized separately. We present the most relevant features of the instrument, the optical design as well as the structural and mechanical layout. Each of the two Prime Focus cameras gather light form a very fast, F/1.14 parabolic primary mirror. The field is corrected over roughly half a degree in size, allowing optical performances in terms of 80 percent of Encircled Energy in better than approximately 0.3 inch. Focal length is slightly increased in order to provide a better sampling using 13.5 micrometers pixel size chips. The CCD array is made up with 4 EEV 42-90 chips, per channel, to obtain an equivalent 6000 by 6000 pixels optimizing the AR coating to the U,B,V and V,R,I,Z bands respectively. The array will be read out in 10 seconds using a 1Meegapixel/second controller with four video channels. The cryostat will use a state of the art dewar to reach an holding time of several days using a limited amount of liquid nitrogen. The whole mechanical design has bene modeled using Finite Elements analysis in order to check for mechanical flexures of the mount tube and of the optical components by themselves. A brief overview of the informative facilities to be provided with the instrument and of a few science case studies that can be attacked by this instrument are also given.

Since March 1997, the TNG Telescope is int its Commissioning phase. In this paper, we describe the structure of the control software of TNG and the on-going activity of the software integration team. The Telescope Communication Network has been completely installed, the control software has been set up and the integration phase is currently in progress. The TNG control software has been designed having in mind the needs of a modern telescope control system: it is based on stable and widespread industry standards; its architecture is fully modular and intrinsically open in order to allow future enhancements and/or modifications of its components. Moreover, the code was written paying a particular attention to its portability. All these characteristics make the TNG control system open to future technology evolutions, both hardware and software-wise. The TNG control software provides a coherent environment where the information flow is constantly guided and controlled through its path across the system. Despite the multiplicity and non-homogeneity of the different subsystems, TNG provides the operator a common framework from the raw data gathering, to the real-time applications, up to the operator interface and archiving system. This was made designing and building a set of layers of increasing abstraction that were mapped onto the various physical components. A brief description of the steps followed during the integration of a number of subsystems will be given.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

One of the most advanced features of the Galileo Telescope (TNG) is the tight connection between the control environment for the telescope and instruments and the data handling and archiving system. This specific design feature is aligned with current trends for telescopes of the new generation, such as VLT and Gemini.

A complete software system for the analysis of objective-prism data has been developed in the framework of a collaboration between the Observatories of Trieste and Athens, and has been used successfully to process low-and medium-dispersion (2440 and 830 A/mm at H γ, respectively) objective prism spectra taken with the 1.2m UK Schmidt Telescope in Australia. The system has been derived from a former one (Balestra et al. 1990) in terms of basic operations, and takes advantage of new data processing technologies.

A long-term multi-purpose observational programme has started with HARPS-N@TNG aimed to characterise the global architectural properties of exoplanetary systems. In this first paper we fully characterise the transiting system Qatar-1. We exploit HARPS-N high-precision radial velocity measurements obtained during a transit to measure the Rossiter-McLaughlin effect in the Qatar-1 system, and out-of-transit measurements to redetermine the spectroscopic orbit. New photometric transit light-curves are analysed and a spectroscopic characterisation of the host star atmospheric parameters is performed based on various methods (line equivalent width ratios, spectral synthesis, spectral energy distribution). We achieved a significant improvement in the accuracy of the orbital parameters and derived the spin-orbit alignment of the system; this information, combined with the spectroscopic determination of the host star properties, allows us to derive the fundamental physical parameters for star and planet (masses and radii). The orbital solution for the Qatar-1 system is consistent with a circular orbit and the system presents a sky-projected obliquity of lambda = -8.4+-7.1 deg. The planet, with a mass of 1.33+-0.05 M_J, is found to be significantly more massive than previously reported. The host star is confirmed to be metal-rich ([Fe/H]= 0.20+-0.10) and slowly rotating (vsinI = 1.7+-0.3 km/s), though moderately active, as indicated by strong chromospheric emission in the Ca II H&K line cores (logR'_HK about -4.60). The system is well aligned and fits well within the general lambda vs Teff trend. We definitely rule out any significant orbital eccentricity. The evolutionary status of the system is inferred based on gyrochronology, and the present orbital configuration and timescale for orbital decay are discussed in terms of star-planet tidal interactions., 12 pages, 8 figures

Data retrieval systems are an essential tool for scientists. Up to a few years ago, user interaction was usually fairly poor, and very often different from one Hardware/Software environment to another. Since one year or less, several portable and user-friendly interactive tools for Network Information Retrieval (NIR) gave us a new and exciting way of interacting with the data in general, and with the astrophysical data in particular. The huge amount of data of astrophysical interest can now be accessed with less pain than ever. The Interstellar Space Mosaic is aimed to be a first attempt to allow transparent access to interstellar medium data in the new NIR scenario, trying to take full advantage of the new tools. This paper will describe the logic structure of this “distributed database of archives”, the data that will become soon available thru it, the advantages (many) and traps (very few) that this new tool is expected to provide.

A spectral classification scheme has been developed for objective prism spectra of LMC stars, taken with the 1.2 m UK Schmidt Telescope in Australia. Various line ratios, discontinuities, and continuum intensities have been used as criteria. The scheme is a 2-D system (spectral type — luminosity class), and the criteria are given in graphical form. The typical accuracy of our scheme is 2 subdivisions of spectral type. Comparison of our types with those given by other authors for common stars yields a very good correlation with deviations within our accuracy.

We present VisIVO a software for the visualisation and analysis of astrophysical data which can be retrieved from the Virtual Observatory framework and for cosmological simulations. VisIVO is VO standards compliant and supports the most important astronomical data formats such as FITS, HDF5 and VOTables. Data can be retrieved directly connecting to an available VO service (i.e., VizieR WS), loaded in the local computer memory where they can be further selected, visualised and manipulated.

The ellipticities of the most populous MC star clusters (87) have been derived for studying a) ellipticity variations within individual clusters, b) variations of ellipticity distributions for various galaxies, and c) variations of ellipticity of star clusters relative to their dynamical parameters.From the studied clusters it is found that radial ellipticity variations within individual clusters seem to be a common phenomenon for the MC clusters where the inner parts are more elliptical than the outer. The SMC clusters are more elliptical than LMC clusters where ellipticities are measured at rh.The dynamical masses of the clusters seem to correlate with ellipticities where the most massive are the most elliptical.

A system based on a multi-layer feed-forward neural network is presented, which is able to detect and extract single, multiple or overlapped spectra from objective prism images, and to perform a coarse classification. The data obtained are currently fed to subsequent wavelength calibration and detailed rule-based classification steps. Given the encouraging results obtained, we plan to use the neural network approach to perform the immediate classification of the extracted spectra with an accuracy of about 2 spectral sub-classes.