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Hardware Definition NI-Maintenance Setup
Get PDFThe NISP maintenance setup is located at INAF-OAS Bologna premises at room 606 at the 4th floor of the INAF building (Istituto Nazionale di Astrofisica - Osservatorio di Astrofisica e Scienza dello Spazio Bologna, Via Piero Gobetti, 93/3, 40129 Bologna BO).
This setup, described in this document, is aimed to the software maintenance of the NISP warm electronics - ICU and DPU instruments of the NISP system of the EUCLID mission, i.e. ICU and DPU Application Software (ASW)
Thermonuclear explosions on neutron stars reveal the speed of their jets
Get PDFRelativistic jets are observed from accreting and cataclysmic transients throughout the Universe, and have a profound impact on their surroundings1,2. Despite their importance, their launch mechanism is not known. For accreting neutron stars, the speed of their compact jets can reveal whether the jets are powered by magnetic fields anchored in the accretion flow3 or in the star itself4,5, but so far no such measurements exist. These objects can show bright explosions on their surface due to unstable thermonuclear burning of recently accreted material, called type-I X-ray bursts6, during which the mass-accretion rate increases7–9. Here, we report on bright flares in the jet emission for a few minutes after each X-ray burst, attributed to the increased accretion rate. With these flares, we measure the speed of a neutron star compact jet to be v=0.38−0.08+0.11c, much slower than those from black holes at similar luminosities. This discovery provides a powerful new tool in which we can determine the role that individual system properties have on the jet speed, revealing the dominant jet launching mechanism
The SARAO MeerKAT 1.3 GHz Galactic Plane Survey
Get PDFWe present the SARAO MeerKAT Galactic Plane Survey (SMGPS), a 1.3 GHz continuum survey of almost half of the Galactic Plane (251◦ ≤l ≤ 358◦ and 2◦ ≤l ≤ 61◦ at |b| ≤ 1◦.5). SMGPS is the largest, most sensitive, and highest angular resolution 1 GHz survey of the plane yet carried out, with an angular resolution of 8 arcsec and a broad-band root-mean-square sensitivity of ∼10–20 μJy beam−1. Here, we describe the first publicly available data release from SMGPS which comprises data cubes of frequency-resolved images over 908–1656 MHz, power-law fits to the images, and broad-band zeroth moment integrated intensity images. A thorough assessment of the data quality and guidance for future usage of the data products are given. Finally, we discuss the tremendous potential of SMGPS by showcasing highlights of the Galactic and extragalactic science that it permits. These highlights include the discovery of a new population of non-thermal radio filaments; identification of new candidate supernova remnants, pulsar wind nebulae and planetary nebulae; improved radio/mid-infrared classification of rare luminous blue variables and discovery of associated extended radio nebulae; new radio stars identified by Bayesian cross-matching techniques; the realization that many of the largest radio-quiet Wide-field Infrared Survey Explorer (WISE) H II region candidates are not true H II regions; and a large sample of previously undiscovered background H I galaxies in the Zone of Avoidance
PDRs4All: III. JWST's NIR spectroscopic view of the Orion Bar
Get PDFContext. JWST has taken the sharpest and most sensitive infrared (IR) spectral imaging observations ever of the Orion Bar photodis-sociation region (PDR), which is part of the nearest massive star-forming region the Orion Nebula, and often considered to be the 'prototypical' strongly illuminated PDR. Aims. We investigate the impact of radiative feedback from massive stars on their natal cloud and focus on the transition from the H II region to the atomic PDR – crossing the ionisation front (IF) –, and the subsequent transition to the molecular PDR – crossing the dissociation front (DF). Given the prevalence of PDRs in the interstellar medium and their dominant contribution to IR radiation, understanding the response of the PDR gas to far-ultraviolet (FUV) photons and the associated physical and chemical processes is fundamental to our understanding of star and planet formation and for the interpretation of any unresolved PDR as seen by JWST. Methods. We used high-resolution near-IR integral field spectroscopic data from NIRSpec on JWST to observe the Orion Bar PDR as part of the PDRs4All JWST Early Release Science programme. We constructed a 3″ × 25″' spatio-spectral mosaic covering 0.97– 5.27 μm at a spectral resolution R of ~2700 and an angular resolution of 0.075″–0.173″. To study the properties of key regions captured in this mosaic, we extracted five template spectra in apertures centred on the three H2 dissociation fronts, the atomic PDR, and the H II region. This wealth of detailed spatial-spectral information was analysed in terms of variations in the physical conditions-incident UV field, density, and temperature – of the PDR gas. Results. The NIRSpec data reveal a forest of lines including, but not limited to, He I, H I , and C I recombination lines; ionic lines (e.g. Fe III and Fe II); O I and N I fluorescence lines; aromatic infrared bands (AIBs, including aromatic CH, aliphatic CH, and their CD counterparts); pure rotational and ro-vibrational lines from H2; and ro-vibrational lines from HD, CO, and CH+, with most of them having been detected for the first time towards a PDR. Their spatial distribution resolves the H and He ionisation structure in the Huygens region, gives insight into the geometry of the Bar, and confirms the large-scale stratification of PDRs. In addition, we observed numerous smaller-scale structures whose typical size decreases with distance from θ1 Ori C and IR lines from C I , if solely arising from radiative recombination and cascade, reveal very high gas temperatures (a few 1000 K) consistent with the hot irradiated surface of small-scale dense clumps inside the PDR. The morphology of the Bar, in particular that of the H2 lines, reveals multiple prominent filaments that exhibit different characteristics. This leaves the impression of a 'terraced' transition from the predominantly atomic surface region to the CO-rich molecular zone deeper in. We attribute the different characteristics of the H2 filaments to their varying depth into the PDR and, in some cases, not reaching the C+/C/CO transition. These observations thus reveal what local conditions are required to drive the physical and chemical processes needed to explain the different characteristics of the DFs and the photochemical evolution of the AIB carriers. Conclusions. This study showcases the discovery space created by JWST to further our understanding of the impact radiation from young stars has on their natal molecular cloud and proto-planetary disk, which touches on star and planet formation as well as galaxy evolution...
Managing the mass production for the LAD instrument onboard eXTP
Get PDFThe Enhanced X-ray Timing and Polarimetry (eXTP) mission is a flagship astronomy mission led by the Chinese Academy of Sciences (CAS) and scheduled for launch in 2029. The Large Area Detector (LAD) is one of the instruments on board eXTP and is dedicated to studying the timing of X-ray sources with unprecedented sensitivity. The development of the eXTP LAD involves a significant mass production of elements to be deployed in a significant number of countries (Italy, Austria, Germany, Poland, China, Czech Republic, France). This feature makes the Manufacturing, Assembly, Integration and Test (MAIT), Verification and Calibration the most challenging and critical tasks of the project. An optimized Flight Model (FM) implementation plan has been drawn up, aiming at a production rate of 2 Modules per week. This plan is based on the interleaving of a series of parallel elementary activities in order to make the most efficient use of time and resources and to ensure that the schedule is met
Engineering a whole sky one meter class telescope: MezzoCielo as a patrol of transients
Get PDFMezzoCielo is a project of a monocentric optical system with a spherical glass envelope built up by meniscus arranged onto a Platonic or Fullerene-like structure filled with industrial liquid characterized by high transparency and low refractive index. Optical design of the cameras, implying the choice between large multiplexing and moderate individual field of view vs. a limited amount of cameras aiming to correct a much larger individual field of view is discussed, along with the current status of the engineering aspects of its design. A case study for such a telescope as a patrol of GW telescope in order to allow almost real-time pinpointing of the associated multimessengers potential sources is given, showing its capability to explore a unique science
The two roles of the SPH Kernel and dissipation on accretion disc modelling in semi-detached Low-Mass Close Binaries
Get PDFThis study addresses two aspects of the SPH technique. The first aspect regards the 3D (2D) numerical integration. The second aspect deals with the necessary damping for handling inviscid flow discontinuities. Accretion discs in Low-Mass Close Binaries (LMCBs) are a context pushing the limit of SPH codes since turbulence, shocks, and shear flows coexist. Thus, an LMCB with high mass-transfer from the inner Lagrangian point is considered. This choice is made for an in-depth understanding of the numerical and physical aspects related to pressure forces computed through SPH Kernel spatial gradients in high-speed collisional flows. In this regard, gas compressibility also plays a role. Firstly, we pay attention to the algebraic term 4πr2 coming from the cubic differential d3r and affecting any 3D SPH integration. This is made through a comparison of physically inviscid SPH structures referring to the same LMCB and mass-transfer conditions. Then, a reformulation of the non-viscous damping is also considered by adopting a Lagrangian-free physical formulation. Inviscid accretion discs should develop a steady toroidal structure because radial transport mechanisms should be excluded by missing any radial shear flow damping. Therefore, thinner discs, also including a steady toroidal ring, identify that SPH inviscid modelling free of any incorrect pressure gradient excess among thick disc structures. This task is simplified since initial conditions deliberately favour thick discs. The physically viscous hydrodynamics of the disc is also addressed by adopting a Prandtl-like turbulent kinematic viscosity coefficient in the Navier–Stokes equations, distinguishing the roles of the bulk and shear viscosities
Report EduINAF anno 2022/2023
Get PDFNel 2022/2023 (Settembre 2022-Agosto 2023), a conclusione dell’emergenza COVID, le attività scolastiche e
le manifestazioni divulgative sono tornate a pieno regime in presenza in tutta Italia. Il 2022/2023 è stato
anche il quarto anno di attività della testata online registrata EduINAF, il magazine di Didattica e Divulgazione
dell’Istituto Nazionale di Astrofisica.
In questo periodo, EduINAF ha visto i propri lettori continuare ad aumentare e alcune delle iniziative nate
negli anni passati diventare strutturali. Oltre a pubblicare risorse didattiche e contenuti informativi sul mondo
della Didattica e Divulgazione della scienza, la redazione ha continuato a organizzare o a collaborare
all’organizzazione di numerose iniziative a sostegno della scuola e della società, come le dirette osservative
della Serie “Il Cielo in Salotto”, i concorsi per le scuole e altre campagne di engagement.
In questo Report si presentano le attività EduINAF organizzate nell’anno, analizzando i risultati ottenuti in
termini di audience, di comportamento e di gradimento del pubblico, con l’obiettivo di tracciare delle linee
guida per la programmazione del prossimo anno scolastico
Assemblaggio e test di laboratorio del Compact Triband Receiver di Medicina
Get PDFDescrizione delle attività di assemblaggio e test del Compact TriBand Receiver per l'antenna parabolica "Gavril Grueff Radio Telescope" della Stazione Radioastronomica di Medicina dell'INAF-IR
Il supporto ai finanziamenti di FROG Fund Raising Office Group - INAF OaPD: report sui cinque anni di attività (2019-2023)
Get PDFIl gruppo FROG (Fund Raising Office Group), e quindi il Servizio Finanziamenti alla ricerca di INAFOaPD è stato costituito nel 2019 presso l’INAF – Osservatorio di Padova con lo scopo di “reperire fondi” ovvero fornire informazioni, assistenza e supporto al personale della struttura, nella ricerca e nella partecipazione a programmi/bandi di finanziamento negli ambiti disciplinari scientifici e tecnologici afferenti all’Istituto, ma anche nei settori afferenti alla terza missione quali la formazione, disseminazione e valorizzazione dei risultati della ricerca e il patrimonio culturale.
L’obiettivo è quello di essere complementare e non un duplicato rispetto alle attività dell’unità scientifica centrale INAF USC VII - Bandi competitivi, favorendo la conoscenza della programmazione Europea e i relativi strumenti di finanziamento legati al settore della ricerca e
innovazione, ma focalizzandosi sui programmi finanziati dai Fondi Europei di Sviluppo Regionale (FESR), e ricercando finanziamenti proposti da Fondazioni Bancarie. Ma non solo: con riferimento a tematiche afferenti alla terza missione, guarda ai programmi rivolti all’educazione e formazione e in particolare per una formazione non formale e informale, come il programma Erasmus+ nei suoi diversi settori (istruzione scolastica, istruzione superiore, istruzione e formazione professionale ed educazione degli adulti), e infine i programmi legati alla cultura e al patrimonio culturale quale il programma Creative Europe. Il report vuole fornire una panoramica di quanto realizzato nei cinque anni della sua costituzione, comunque influenzati dalla pandemia, analizzando i risultati ottenuti e le criticità evidenziate, pur sostenendo la necessità di una maggiore conoscenza delle politiche europee e degli strumenti di finanziamento messi a disposizione per le diverse attività