Expected performances of a Laue lens made with bent crystals

In the context of the LAUE project devoted to build a Laue lens prototype for focusing celestial hard X-/soft gamma-rays, a Laue lens made of bent crystal tiles, with 20 m focal length, is simulated. The focusing energy passband is assumed to be 90--600 keV. The distortion of the image produced by the lens on the focal plane, due to effects of crystal tile misalignment and radial distortion of the crystal curvature, is investigated. The corresponding effective area of the lens, its point spread function and sensitivity are calculated and compared with those exhibited by a nominal Laue lens with no misalignment and/or distortion. Such analysis is crucial to estimate the optical properties of a real lens, in which the investigated shortcomings could be present.Comment: 20 pages, 14 figure

Hard x-ray broad band Laue lenses (80 - 600 keV): building methods and performances

We present the status of the laue project devoted to develop a technology for building a 20 meter long focal length Laue lens for hard x-/soft gamma-ray astronomy (80 - 600 keV). The Laue lens is composed of bent crystals of Gallium Arsenide (GaAs, 220) and Germanium (Ge, 111), and, for the first time, the focusing property of bent crystals has been exploited for this field of applications. We show the preliminary results concerning the adhesive employed to fix the crystal tiles over the lens support, the positioning accuracy obtained and possible further improvements. The Laue lens petal that will be completed in a few months has a pass band of 80 - 300 keV and is a fraction of an entire Laue lens capable of focusing X-rays up to 600 keV, possibly extendable down to 20 - 30 keV with suitable low absorption crystal materials and focal length. The final goal is to develop a focusing optics that can improve the sensitivity over current telescopes in this energy band by 2 orders of magnitude

The LAUE project for broadband gamma-ray focusing lenses

We present the LAUE project devoted to develop an advanced technology for building a high focal length Laue lens for soft gamma--ray astronomy (80-600 keV). The final goal is to develop a focusing optics that can improve the current sensitivity in the above energy band by 2 orders of magnitude.Comment: 7 pages, 6 figures, presented at the SPIE conference on "Optics for EUV, X-ray, and Gamma-ray Astronomy". To be published in the Proceedings of SPIE, vol.8147, 201

Monitoring of the conservation state of the internal wall surfaces of Room with Golden Vault in the Domus Aurea

This project describes the monitoring campaign, performed in situ with the collaboration of Konica Minolta Sensing Europe, in order to verify the actual conservation state of the internal wall surfaces of the Room with Golden Vault in the Domus Aurea in Rome. Particularly, the main aim of this work was to evaluate the problems caused by aggressive environmental conditions (combination of low air temperature and high relative humidity). During this survey, characterized by the integrated use of two and three-dimensional techniques, the environmental conditions were carefully monitored. Reference sample regions of the vault were acquired by means of the 3D laser scanner Konica Minolta Vivid 9i (optical triangulation-based) that allows capturing morphological details of the stucco decorations with a good resolution. Moreover, each detailed scan was supplied with related high resolution images taken by a digital reflex camera Olympus E-510 rigidly connected to the scanner. In Cultural Heritage monitoring applications it is important to integrate the data acquired with different instruments and techniques. Therefore, by this methodological approach, it has been possible to integrate both two and three dimensional data by the projection of the acquired images on the corresponding digital model. In order to complete the cognitive framework of the vault, systematic measures of spectrophotometry by means of the portable spectrophotometer Minolta 2600d were also carried out. The digital data, collected and elaborated by this monitoring campaign, allowed to create a database of morphological information, high resolution digital images, colorimetric values and reflectance curves that may be used in the future as reference data to periodically monitor the conservation state of the surfaces

Development status of the LAUE project

We present the status of LAUE, a project supported by the Italian Space Agency (ASI), and devoted to develop Laue lenses with long focal length (up to 100 meters), for hard X--/soft gamma--ray astronomy (80-600 keV). Thanks to their focusing capability, the design goal is to improve the sensitivity of the current instrumention in the above energy band by 2 orders of magnitude, down to a few times $10^{-8}$ photons/(cm$^2$ s keV).Comment: 9 pages, 9 figures, presented at the Space Telescopes and Instrumentation Symposium in Amsterdam, 2012: Ultraviolet to Gamma Ray Conference. Published in the Proceedings of the SPIE, Volume 8443, id. 84430B-84430B-9 (2012

The LAUE project: latest developments

We present the status of the LAUE project devoted to develop a technology for building long focal length Laue lenses for hard X-/soft gamma-ray astronomy (80-600 keV). The Laue lens will be composed of bent crystals of Gallium Arsenide (GaAs, 220) and Germanium (Ge, 111), and, for the first time, the focusing property of bent crystals will be exploited for this field of applications. At the present the goal of the project is the building of a 20 m focal length Laue lens petal capable of focusing X-ray in the energy range 90-300 keV

Scientific prospects in soft gamma-ray astronomy enabled by the LAUE project

This paper summarizes the development of a successful project, LAUE, supported by the Italian Space Agency (ASI) and devoted to the development of long focal length (up to 100 m) Laue lenses for hard X--/soft gamma--ray astronomy (80-600 keV). The apparatus is ready and the assembling of a prototype lens petal is ongoing. The great achievement of this project is the use of bent crystals. From measurements obtained on single crystals and from simulations, we have estimated the expected Point Spread Function and thus the sensitivity of a lens made of petals. The expected sensitivity is a few $\times10^{-8}$ photons cm$^{-2}$ s$^{-1}$ keV$^{-1}$. We discuss a number of open astrophysical questions that can settled with such an instrument aboard a free-flying satellite.Comment: 17 pages, 18 figures, published in Proceedings of the SPIE, Volume 8861, id. 886106 17 pp. (2013

New results on focusing of gamma-rays with Laue lenses

We report on new results on the development activity of broad band Laue lenses for hard X-/gamma-ray astronomy (70/100-600 keV). After the development of a first prototype, whose performance was presented at the SPIE conference on Astronomical Telescopes held last year in Marseille (Frontera et al. 2008), we have improved the lens assembling technology. We present the development status of the new lens prototype that is on the way to be assembled.Comment: 8 pages, 11 figures, to be Published in SPIE Proceedings, vol.7437-19, 200

Il consolidamento degli apparati decorativi mediante dispositivi a memoria di forma: il progetto di ricerca sui dipinti murali di via dell’Abbondanza a Pompei

Il progetto di ricerca, iniziato durante il cantiere di restauro, recentemente concluso, ha riguardato gli interventi di consolidamento, conservazione e restauro su alcune facciate delle antiche botteghe di via dell'Abbondanza (Regio IX, Insulae 7 e 11) nel sito archeolo-gico di Pompei. Questi fronti sono caratterizzati da alcuni dei dipinti murali più importanti e le iscrizioni elettorali. Il progetto denominato “Da Asellina a Verecundus: ricerca, restauro e monitoraggio sulle pitture di alcune celebri botteghe di via dell'Abbondanza a Pompei (Regio IX, Insulae 7 e 11)” nato dalla collaborazione fra la Soprintendenza Ar-cheologica di Pompei, la Facoltà di Architettura Valle Giulia dell’Università di Roma La Sapienza, la Facoltà di Architettura e il Centro DIAPReM dell’Università di Ferrara e la II Facoltà di Ingegneria (sede di Forlì) dell’Università di Bologna, con l’obiettivo della salva-guardia di alcune strutture architettoniche e degli apparati pittorici e decorativi fra i più importanti di tutta la città. L’intervento di restauro, in particolare, ha riguardato alcune botteghe poste sul braccio del decumano massimo compreso fra il Foro e Porta Sarno. Tali facciate, riportate alla luce durante gli scavi condotti nel 1912 da Vittorio Spinazzola, appartengono all’officina coactiliaria (Regio IX, VII, 7-5); ad una casa privata (Regio IX, VII, 3); all’officina infectoria (Regio IX, VII, 2); all’officina coactiliaria (Regio IX, VII,1); al compitum (Regio IX, XI, 1); al thermopolium di Asellina, rivendita di bevande calde (Regio IX, XI, 2). Una sezione del progetto di ricerca ha riguardato la sperimentazione di nuovi dispositivi tecnologici finalizzati al restauro di pitture murali e basati su leghe a memoria di forma (SMA) per risolvere i problemi di consolidamento altrimenti risolto per mezzo di non-reversibile o invadente metodologie. Una delle applicazioni innovative di questi dispositivi riguarda il movimento delle lastre in policarbonato in grado di proteggere le pit-ture murali. Il particolare contesto del progetto di ricerca è collocato sul confine tra l'area scavata e l'area ancora sepolta, così, è stato particolarmente interessante mettere a fuoco le ricerche sul consolidamento delle decorazioni e pitture murali, anche attraverso lo studio delle interventi di Vittorio Spinazzola durante i lavori di scavo, all'inizio del XX secolo