Towards a novel concept of imaging spectrograph

L'obiettivo della presente tesi è di introdurre una nuova concezione di fotorivelatore astrofisico, in grado di analizzare immediatamente la composizione spettrale di immagini bidimensionali. Prima di tutto, la sua innovativa tecnologia, che si basa sull'effetto superconduttivo dell'induttanza cinetica, è confrontata con lo standard dei dispositivi semiconduttivi ad accoppiamento di carica. Essi contano sull'effetto fotoelettrico e possono solo percepire l'intensità della luce su un periodo d'esposizione, di per sé, senza elementi dispersivi o filtri monocromatici dinnanzi. In questo contesto, riporto il risultato della mia collaborazione con l'Università di Oxford, dov'è in via di sviluppo uno spettrografo a campo integrale chiamato KIDSpec, operativo nella banda elettromagnetica che va dall'ultravioletto al vicino infrarosso. Sarà il primo strumento di tal sorta ad essere costruito al di fuori degli Stati Uniti d'America. Il mio compito consisteva nell'assemblare uno spettrometro ottico destinato ad uno studio di fattibilità di questo apparato. Quindi, le carenze del sistema ottico sono discusse in breve, in vista della sua implementazione. A seguire, le indagini ottiche attraverso cui esaminai la prestazione dello spettrometro, quanto alle sue risposte in fatto di diffrazione, a varî angoli d'uscita e lunghezze d'onda in ingresso. In aggiunta, si fornisce un'eziologia dei motivi circolari causati dalla fibra ottica ivi impiegata. Infine, sono esaminate alcune possibili applicazioni astrofisiche del nuovo tipo di rivelatore: particolare attenzione è data all'emergente frontiera della caratterizzazione esoplanetaria diretta

Resolving Power of Visible to Near-Infrared Hybrid β\beta-Ta/NbTiN Kinetic Inductance Detectors

Kinetic Inductance Detectors (KIDs) are superconducting energy-resolving detectors, sensitive to single photons from the near-infrared to ultraviolet. We study a hybrid KID design consisting of a beta phase tantalum ($\beta$-Ta) inductor and a NbTiN interdigitated capacitor (IDC). The devices show an average intrinsic quality factor $Q_i$ of 4.3$\times10^5$ $\pm$ 1.3 $\times10^5$. To increase the power captured by the light sensitive inductor, we 3D-print an array of 150$\times$150 $\mu$m resin micro lenses on the backside of the sapphire substrate. The shape deviation between design and printed lenses is smaller than 1$\mu$m, and the alignment accuracy of this process is $\delta_x = +5.8 \pm 0.5$ $\mu$m and $\delta_y = +8.3 \pm 3.3$ $\mu$m. We measure a resolving power for 1545-402 nm that is limited to 4.9 by saturation in the KID's phase response. We can model the saturation in the phase response with the evolution of the number of quasiparticles generated by a photon event. An alternative coordinate system that has a linear response raises the resolving power to 5.9 at 402 nm. We verify the measured resolving power with a two-line measurement using a laser source and a monochromator. We discuss several improvements that can be made to the devices on a route towards KID arrays with high resolving powers.Comment: 11 pages, 9 Figues, Journal Pape

Pyxel 1.0: an open source Python framework for detector and end-to-end instrument simulation

Detector modeling is becoming more and more critical for the development of new instruments in scientific space missions and ground-based experiments. Modeling tools are often developed from scratch by each individual project and not necessarily shared for reuse by a wider community. To foster knowledge transfer, reusability, and reliability in the instrumentation community, we developed Pyxel, a framework for the simulation of scientific detectors and instruments. Pyxel is an open-source and collaborative project, based on Python, developed as an easy-to-use tool that can host and pipeline any kind of detector effect model. Recently, Pyxel has achieved a new milestone: the public release and launch of version 1.0, which simplified third-party contributions and improved ease of use even further. Since its launch, Pyxel has been experiencing a growing user community and is being used to simulate a variety of detectors. We give a tour of Pyxel’s version 1.0 changes and new features, including a new interface, parallel computing, and new detectors and models. We continue with an example of using Pyxel as a tool for model optimization and calibration. Finally, we describe an example of how Pyxel and its features can be used to develop a full-scale end-to-end instrument simulator

Pyxel: the collaborative detection simulation framework

Pyxel is a novel python tool for end-to-end detection chain simulation i.e. from detector optical effects to readout electronics effects. It is an easy-to-use framework to host and pipeline any detector effect model. It is suited for simulating both Charge-Coupled Devices, CMOS Image Sensors and Mercury Cadmium Telluride hybridized arrays. It is conceived as a collaborative tool to promote reusability, knowledge transfer, and reliability in the instrumentation community. We provide a demonstration of Pyxel's basic principles, describe newly added capabilities, and give examples of more advanced applications

Resolving Power of Visible-To-Near-Infrared Hybrid β-Ta/Nb-Ti- N Kinetic Inductance Detectors

Kinetic inductance detectors (KIDs) are superconducting energy-resolving detectors, sensitive to single photons from the near-infrared to ultraviolet. We study a hybrid KID design consisting of a β-phase tantalum (β-Ta) inductor and a Nb-Ti-N interdigitated capacitor. The devices show an average intrinsic quality factor Qi of 4.3×105±1.3×105. To increase the power captured by the light-sensitive inductor, we 3D print an array of 150×150μm resin microlenses on the backside of the sapphire substrate. The shape deviation between design and printed lenses is smaller than 1μm, and the alignment accuracy of this process is δx=+5.8±0.5μm and δy=+8.3±3.3μm. We measure a resolving power for 1545-402 nm that is limited to 4.9 by saturation in the KID's phase response. We can model the saturation in the phase response with the evolution of the number of quasiparticles generated by a photon event. An alternative coordinate system that has a linear response raises the resolving power to 5.9 at 402 nm. We verify the measured resolving power with a two-line measurement using a laser source and a monochromator. We discuss several improvements that can be made to the devices on a route towards KID arrays with high resolving powers. </p

Pyxel 1.0: an open source Python framework for detector and end-to-end instrument simulation

Detector modelling is becoming more and more critical for the successful development of new instruments in scientific space missions and ground-based experiments. Specific modelling tools are often developed from scratch by each individual project and not necessarily shared for reuse by a wider community. To foster knowledge transfer, reusability and reliability in the instrumentation community, ESA and ESO joined forces and developed Pyxel, a framework for the simulation of scientific detectors and instruments. Pyxel is an open-source and collaborative project, based on Python, developed as an easy-to-use tool that can host and pipeline any kind of detector effect model. Recently Pyxel has achieved a new milestone: the public release and launch of version 1.0 which simplified third-party contributions and improved ease of use even further. Since its launch, Pyxel has been experiencing a growing user community and is being used to simulate all kinds of detectors beyond the traditional Charged-Coupled Devices and CMOS devices, for example Microwave Kinetic Inductance Detectors (MKID) and Avalanche Photo Diode (APD) devices. We give a tour of Pyxel’s version 1.0 changes and new features including a new interface, parallel computing, and new detectors and models. We continue with an example of using Pyxel as a tool for model optimization and calibration. Finally, we describe an example of how Pyxel and its features can be used to develop a full-scale end-to-end instrument simulator

The MICADO first light imager for the ELT: preliminary design of the MICADO Calibration Assembly

The paper describes the preliminary design of the MICADO calibration assembly. MICADO, the Multi-AO Imaging CAmera for Deep Observations, is targeted to be one of the first light instruments of the Extremely Large Telescope (ELT) and it will embrace imaging, spectroscopic and astrometric capabilities including their calibration. The astrometric requirements are particularly ambitious aiming for 50 μas differential precision within and between single epochs. The MICADO Calibration Assembly (MCA) shall deliver flat-field, wavelength and astrometric calibration and it will support the instrument alignment to the Single-Conjugate Adaptive Optics wavefront sensor. After a complete overview of the MCA subsystems, their functionalities, design and status, we will concentrate on the ongoing prototype testing of the most challenging components. Particular emphasis is put on the development and test of the Warm Astrometric Mask (WAM) for the calibration of the optical distortions within MICADO and MAORY, the multiconjugate AO module

The ESO’s Extremely Large Telescope Working Groups

Since 2005 ESO has been working with its community and industry to develop an extremely large optical/infrared telescope. ESO’s Extremely Large Telescope, or ELT for short, is a revolutionary ground-based telescope that will have a 39-metre main mirror and will be the largest visible and infrared light telescope in the world. To address specific topics that are needed for the science operations and calibrations of the telescope, thirteen specific working groups were created to coordinate the effort between ESO, the instrument consortia, and the wider community. We describe here the goals of these working groups as well as their achievements so far

The Second International Asteroid Warning Network Timing Campaign: 2005 LW3

The Earth close approach of near-Earth asteroid 2005 LW3 on 2022 November 23 represented a good opportunity for a second observing campaign to test the timing accuracy of astrometric observation. With 82 participating stations, the International Asteroid Warning Network collected 1046 observations of 2005 LW3 around the time of the close approach. Compared to the previous timing campaign targeting 2019 XS, some individual observers were able to significantly improve the accuracy of their reported observation times. In particular, U.S. surveys achieved good timing performance. However, no broad, systematic improvement was achieved compared to the previous campaign, with an overall negative bias persisting among the different observers. The calibration of observing times and the mitigation of timing errors should be important future considerations for observers and orbit computers, respectively.Funder: Institute of Cosmos SciencesUniversity of Barcelona (CEX2019-000918-M); European Union (PID2021-122842OB-C21);Full text license: CC BY</p