Feasibility study of observing binary systems with the ASTRI Mini-array

openTheorized by Glauber in the 1960s, Intensity Interferometry (II) has found applications in a wide variety of fields. The first to use it for astronomical measurements, albeit in its "analog" form, were Hanbury-Brown and Twiss, culminating their research by measuring the angular diameter of more than thirty stars from the Narrabri observatory, in Australia. Very recently, a research group at the University of Padua and at the Observatory of Padova of the National Institute of Astrophysics realized the first astronomical intensity interferometry measurement by means of a "quantum" approach, determining the second order correlation function of Vega using two ultrafast photon counting photometers coupled to two mid-class telescopes available at Asiago (Italy). Nowadays, due to the planned construction of large telescope arrays (e.g. CTA), and thanks to the enormous advances in electronics, II is acquiring a central role, with great prospects for the further characterization of various celestial bodies. In this context, the objective of this thesis is to evaluate, through simulations, the capabilities of the ASTRI Mini-array telescope system to characterize binary systems using the II technique.Theorized by Glauber in the 1960s, Intensity Interferometry (II) has found applications in a wide variety of fields. The first to use it for astronomical measurements, albeit in its "analog" form, were Hanbury-Brown and Twiss, culminating their research by measuring the angular diameter of more than thirty stars from the Narrabri observatory, in Australia. Very recently, a research group at the University of Padua and at the Observatory of Padova of the National Institute of Astrophysics realized the first astronomical intensity interferometry measurement by means of a "quantum" approach, determining the second order correlation function of Vega using two ultrafast photon counting photometers coupled to two mid-class telescopes available at Asiago (Italy). Nowadays, due to the planned construction of large telescope arrays (e.g. CTA), and thanks to the enormous advances in electronics, II is acquiring a central role, with great prospects for the further characterization of various celestial bodies. In this context, the objective of this thesis is to evaluate, through simulations, the capabilities of the ASTRI Mini-array telescope system to characterize binary systems using the II technique

The HYPSOS optomechanical bench design

In the last years, almost all the planetary missions have included a stereo camera and a spectrograph on-board. These two instruments respectively provide stereo images and spectral information, essential data to characterize a planet's surface. HYPSOS (HYPerspectral Stereo Observing System) is a novel instrument that will be able to merge the function of the two instruments. In fact, it will produce stereo hypercubes and represent 3D data with a fourth dimension: the spectral information.openEmbargo temporaneo per motivi di segretezza e/o di proprietà dei risultati e informazioni di enti esterni o aziende private che hanno partecipato alla realizzazione del lavoro di ricerca relativo alla tes

In-lab characterization of HYPSOS, a novel stereo hyperspectral observing system: first results

HYPSOS (HYPerspectral Stereo Observing System, patented) is a novel remote sensing instrument able to extract the spectral information from the two channels of a pushbroom stereo camera; thus it simultaneously provides 4D information, spatial and spectral, of the observed features. HYPSOS has been designed to be a compact instrument, compatible with small satellite applications, to be suitable both for planetary exploration as well for terrestrial environmental monitoring. An instrument with such global capabilities, both in terms of scientific return and needed resources, is optimal for fully characterizing the observed surface of investigation. HYPSOS optical design couples a pair of folding mirrors to a modified three mirror anastigmat telescope for collecting the light beams from the optical paths of the two stereo channels; then, on the telescope focal plane, there is the entrance slit of an imaging spectrograph, which selects and disperses the light from the two stereo channels on a bidimensional detector. With this optical design, the two stereo channels share the large majority of the optical elements: this allowed to realize a very compact instrument, which needs much less resources than an equivalent system composed by a stereo camera and a spectrometer. To check HYPSOS actual performance, we realized an instrument prototype to be operated in a laboratory environment. The laboratory setup is representative of a possible flight configuration: the light diffused by a surface target is collimated on the HYPSOS channel entrance apertures, and the target is moved with respect to the instrument to reproduce the in- flight pushbroom acquisition mode. Here we describe HYPSOS and the ground support equipment used to characterize the instrument, and show the preliminary results of the instrument alignment activities

The HYPSOS optomechanical bench design

In the last years, almost all the planetary missions have included a stereo camera and a spectrograph on-board. These two instruments respectively provide stereo images and spectral information, essential data to characterize a planet's surface. HYPSOS (HYPerspectral Stereo Observing System) is a novel instrument that will be able to merge the function of the two instruments. In fact, it will produce stereo hypercubes and represent 3D data with a fourth dimension: the spectral information

Piezosurgery Versus Conventional Osteotomy in Orthognathic Surgery

The aim of the study was to compare in a randomized controlled clinical trial the use of the piezoelectric osteotomy as an alternative to the conventional approach in terms of surgery time, intraoperative blood loss, cut quality, nerve injury, and costs. One hundred ten patients who had orthognathic surgery procedures with bimaxillary osteotomy were divided into 2 groups: group A was treated with a piezosurgery device, and group B, with a reciprocating saw and bur. The piezosurgical bone osteotomy permitted individualized cut designs. The surgical time in group A was reduced, with a mean for the mandibular osteotomy (1 side) between 3 minutes 31 seconds and 5 minutes 2 seconds, whereas in group B, the surgical time was between 7 minutes 23 seconds and 10 minutes 22 seconds. The surgical time in group A for the Le Fort I osteotomy was between 5 minutes 17 seconds and 7 minutes 55 seconds in group A and between 8 minutes 38 seconds and 15 minutes 11 seconds in group B. All patients in group A had a low blood loss (G300 mL) versus patients of group B who had a medium to high blood loss (medium loss: 400 mL, high loss: 9500 mL). Inferior alveolar nerve sensation was retained in 98.2% of group A versus 92.7% in group B at 6 months postoperative testing. Piezoelectric osteotomy reduced surgical time, blood loss, and inferior alveolar nerve injury in bimaxillary osteotomy. Absence of macrovibrations makes the instrument more manageable and easy to use and allows greater intraoperative control with higher safety in cutting in difficult anatomical regions

Aeronautics lidar revisited - Towards lidar-based gust and turbulence measurement for aircraft load alleviation control

We give an overview of the authors' and their institutions' latest R&D activities regarding Direct-Detection Doppler-Wind-Lidar (DD-DWL) for the usage as remote flow sensor on civil aircraft. The purpose of such a lidar, when flying through Clear Air Turbulence (CAT) at cruise altitudes, is delivering sufficient turbulent wind information for feeding a chain of gust reconstruction, control and command modules. Hence, aerodynamic effects on the aircraft structure shall be mitigated. The long-standing record of the ONERA and DLR lidar groups in aeronautics' application lidar allowed us recently to team up in the European Clean Aviation Joint Undertaking (CAJU) co-financed project UP Wing with the agenda of maturing the critical technologies (like laser, Doppler spectrometric receiver, etc.) and validating these at component and system level with extensive ground and also airborne tests. Here, we present the main bricks of this technology suite, an overview of some prior and actual achievements and some perspective