ICT ed E-Infrastructures in INAF

Nella storia recente dell’Astrofisica le infrastrutture informatiche sia di calcolo che di archiviazione e fruizione degli archivi sono state di crescente importanza per la produzione di risultati scientifici di eccellenza. Infrastrutture di piccola e media scala, dalla workstation individuale al centro di calcolo di struttura, hanno lasciato posto alla necessità di accesso a medie e grandi infrastrutture centralizzate a cui garantire accesso ai ricercatori. L’adesione dell’INAF a grandi infrastrutture di ricerca di livello mondiale, ad esempio SKA e CTA, e il crescente proliferare di iniziative nazionali, europee e mondiali di creazioni di cluster di calcolo o cloud di archiviazione condivisi, ha ulteriormente innalzato il livello di esigenze, correnti e future, della comunità scientifica rendendo opportuno un cambio di passo a livello di Ente nell’approvvigionamento, gestione, offerta e coordinamento delle risorse di calcolo ed archiviazione per l’Astrofisica. Esiste pertanto un generale consenso nella comunità circa la necessità di riformare ed aggiornare l’offerta di Information technology (ICT) interna ad INAF per adeguarla alle nuove sfide che si prospettano all’orizzonte, legate ad un ruolo sempre più crescente della componente informatica nella produzione, qualificazione, conservazione e fruibilità del dato osservativo e teorico in Astronomia e Astrofisica. La via maestra, in linea con le tendenze internazionali, è la centralizzazione della ubicazione ed erogazione delle risorse in un contesto di competenze distribuite. Infatti una proliferazione non coordinata di centri di calcolo di piccole dimensioni, quanto si otterrebbe distribuendo senza criterio le componenti di nuova acquisizione presso le varie strutture di ricerca, implicherebbe una crescita dei costi indiretti ed una riduzione dell'efficienza del sistema complessivo causata dalla frammentazione. Passi importanti in questa direzione sono già stati intrapresi dall’Ente. Tra questi il più rilevante è senza dubbio l’investimento nel “tecnopolo” di Bologna, occasione per una azione integrata in un contesto dinamico e riconosciuto a livello governativo e nazionale ed in una prospettiva di medio-lungo termine. Altri importanti passi intermedi sono resi possibili da opportunità come quella recentemente concretizzata di rilevare in comodato d’uso parti del cluster denominato “Galileo” in via di dismissione da parte del CINECA. Questo documento presenta una analisi di scenario delle esigenze attuali o previste per il prossimo futuro in termini di infrastrutture informatiche, l’offerta attualmente disponibile a copertura di queste esigenze e la prospettiva di evoluzione dell’offerta a copertura delle esigenze previste. Il documento include inoltre una proposta di futura governance del settore, basata su un soggetto attuatore autonomo, la e-infrastructure di INAF, ed un soggetto preposto al coordinamento, controllo e ruolo abilitante per il settore, la UTG “Astrofisica Computazionale”

Alignment and integration of large optical systems based on advanced metrology

Optical alignment is a key activity in opto-mechanical system Integration. Traditional techniques require adjustable mounting, driven by optical references that allows the tuning of the optics position along all 6 Degree of Freedom. Nevertheless, the required flexibility imposes reduced stiffness and consequently less stability of the system. The Observatory of Brera (OAB) started few years ago a research activity focused onto the overcoming of this limits exploiting the high metrology performances of Coordinate Measuring Machines (CMM) with the main objectives of relax the manufacturing tolerances and maximize mounting stiffness. Through the T-REX grants, OAB acquired all the instrumentation needed for that activity furthermore considering the ESPRESSO project training and testing also oriented to large scale instrumentation like the E-ELT one. We will present in this paper the definition of the VLTs convergence point and the feasibility study of large mirrors alignment done by mechanical measurements methods

A bonnet and fluid jet polishing facility for optics fabrication related to the E-ELT

A robotic polishing machine has been implemented at INAF-Brera Astronomical Observatory within the T-REX project. The facility, IRP1200 by Zeeko Ltd., consists of a 7-axis computer-controlled polishing/forming machine capable of producing precision surfaces on several optical materials. The machine enables two methods, the bonnet and the fluid jet polishing. We report on the results of the standard bonnet polishing machine acceptance tests that have been completed at our site. We intend to use the machine to support development and production programs related to the European Extremely Large Telescope (E-ELT), in particular, for making part of the optics of the Multi-conjugate Adaptive Optics RelaY (MAORY) module. <P /

Integration, alignment, and verification of the ESPRESSO Front-End

ESPRESSO, Echelle SPectrograph for Rocky Exoplanets and Stable Spectroscopic Observations, is now under the assembly, integration and verification phase and will be installed beginning next year at Paranal Observatory on ESO's Very Large Telescopes. The Front End is the modular system in the Combined Coudé Laboratory receiving the light from the four VLT Units, providing the needed connection between the input signal, i.e., object light, sky light, and calibration light, to feed the spectrograph through optical fibers. The modular concept of the FE Units drove the system design and the alignment workflow. We will show the integration method of the single FE modules adopted to guarantee the necessary repeatability between the different Units. The performances of the system in terms of image quality and encircled energy in the observed point spread function are reported. Finally, the strategy followed in the Paranal Combined Coudè Laboratory to define the convergence point of the four UTs is described, along with the procedure used to align the ground plates, the main structure, and the mode selector

Technologies for the fabrication of the E-ELT mirrors within the T-REX project

With its primary mirror with 39 m of diameter, the E-ELT will be the largest optical/near-infrared telescope in the world and will gather 13 times more light than the largest optical telescopes existing today. The different optical sub-systems of E-ELT, including the primary mirror based on hundreds of reflecting tiles assembled together, represent key components for the implementation of the telescopes. A huge amount of aspherical reflecting elements have to be produced with "state of the art" figuring and polishing technologies and measured with proper metrological equipments. In the past couple of years, in the context of the T-REX project, a specific development program was carried out at the Brera Astronomical Observatory-INAF in order to address a numbers of technology aspects related to the fabrication of the E-ELT mirrors. In this paper we give a short overview of the activities that have been carried out. Other papers in this volume report on specific activities that have pursed within such a development program. skip=8p

Preparing the E-ELT M4 optical test

The design of the interferometric test of the adaptive M4 Unit of E-ELT, a deformable six petals 2.4 m mirror, will be described. The actual baseline follows a macro-stitching approach, where each segment is separately flattened and co-phased to the other petals. The optical test setup for the single shell consists in a Newtonian system, with a 1.5 m parabolic mirror as main collimator. A 0.6 m reference flat mirror is foreseen to verify the alignment of the interferometric cavity. A Demonstration Prototype of the final M4 Unit, a 222 actuators, two shells deformable mirror, has been produced by Microgate and A.D.S. International. Results of the optical measurement campaign performed in INAF on the prototype mirror are reported

BATMAN: MOS Spectroscopy on Demand

Multi-Object Spectrographs (MOS) are the major instruments for studying primary galaxies and remote and faint objects. Current object selection systems are limited and/or difficult to implement in next generation MOS for space and ground-based telescopes. A promising solution is the use of MOEMS devices such as micromirror arrays, which allow the remote control of the multi-slit configuration in real time. TNG is hosting a novelty project for real-time, on-demand MOS masks based on MOEMS programmable slits. We are developing a 2048×1080 Digital-Micromirror-Device-based (DMD) MOS instrument to be mounted on the Galileo telescope, called BATMAN. It is a two-arm instrument designed for providing in parallel imaging and spectroscopic capabilities. With a field of view of 6.8×3.6 arcmin and a plate scale of 0.2 arcsec per micromirror, this astronomical setup can be used to investigate the formation and evolution of galaxies. The wavelength range is in the visible and the spectral resolution is R=560 for a 1 arcsec object, and the two arms will have 2k × 4k CCD detectors. ROBIN, a BATMAN demonstrator, has been designed, realized and integrated. We plan to have BATMAN first light by mid-2016

SN 2003lw and GRB 031203: A Bright Supernova for a Faint Gamma-ray Burst

Optical and near-infrared observations of the gamma-ray burst GRB 031203, at z = 0.1055, are reported. A very faint afterglow is detected superimposed to the host galaxy in our first infrared JHK observations, carried out ~9 hours after the burst. Subsequently, a rebrightening is detected in all bands, peaking in the R band about 18 rest-frame days after the burst. The rebrightening closely resembles the light curve of a supernova like SN 1998bw, assuming that the GRB and the SN went off almost simultaneously, but with a somewhat slower evolution. Spectra taken close to the maximum of the rebrightening show extremely broad features as in SN 1998bw. The determination of the absolute magnitude of this SN (SN 2003lw) is difficult owing to the large and uncertain extinction, but likely this event was brighter than SN 1998bw by 0.5 mag in the VRI bands, reaching an absolute magnitude M_V = -19.75+-0.15.Comment: 6 pages, 4 figures. Accepted to ApJ Letters. Fig. 4 will not appear in the journal version due to space limitations. Typos fixed in Table 1 (thanks to Dr. Alexander Kann for pointing out the problem). No measurements change