L3CCD results in pure photon counting mode

Theoretically, L3CCDs are perfect photon counting devices promising high quantum efficiency ($\sim$90%) and sub-electron readout noise ($\sigma$<0.1 e-). We discuss how a back-thinned 512x512 frame-transfer L3CCD (CCD97) camera operating in pure photon counting mode would behave based on experimental data. The chip is operated at high electromultiplication gain, high analogic gain and high frame rate. Its performance is compared with a modern photon counting camera (GaAs photocathode, QE $\sim$28%) to see if L3CCD technology, in its current state, could supersede photocathode-based devices.Comment: 9 pages, 9 figures, to appear in SPIE conference proceedings vol 5499, "Optical & IR Detectors for Astronomy" Glasgow UK, 21-24 June 200

Spiral inflow feeding the nuclear starburst in M83, observed in H-alpha emission with the GHAFAS Fabry-Perot interferometer

We present observations of the nearby barred starburst galaxy, M83 (NGC5236), with the new Fabry-Perot interferometer GHAFAS mounted on the 4.2 meter William Herschel Telescope on La Palma. The unprecedented high resolution observations, of 16 pc/FWHM, of the H-alpha-emitting gas cover the central two kpc of the galaxy. The velocity field displays the dominant disk rotation with signatures of gas inflow from kpc scales down to the nuclear regions. At the inner Inner Lindblad Resonance radius of the main bar and centerd at the dynamical center of the main galaxy disk, a nuclear $5.5 (\pm 0.9) \times 10^8 M_\odot$ rapidly rotating disk with scale length of $60 \pm 20$ pc has formed. The nuclear starburst is found in the vicinity as well as inside this nuclear disk, and our observations confirm that gas spirals in from the outer parts to feed the nuclear starburst, giving rise to several star formation events at different epochs, within the central 100 pc radius of M83.Comment: Accepted for publication in ApJ Letters. High-resolution version can be found at http://www.astro.su.se/~kambiz/DOC/paper-M83.pd

The Brazilian Tunable Filter Imager for the SOAR telescope

This paper presents a new Tunable Filter Instrument for the SOAR telescope. The Brazilian Tunable Filter Imager (BTFI) is a versatile, new technology, tunable optical imager to be used in seeing-limited mode and at higher spatial fidelity using the SAM Ground-Layer Adaptive Optics facility at the SOAR telescope. The instrument opens important new science capabilities for the SOAR community, from studies of the centers of nearby galaxies and the insterstellar medium to statistical cosmological investigations. The BTFI takes advantage of three new technologies. The imaging Bragg Tunable Filter concept utilizes Volume Phase Holographic Gratings in a double-pass configuration, as a tunable filter, while a new Fabry-Perot (FP) concept involves technologies which allow a single FP etalon to act over a large range of interference orders and spectral resolutions. Both technologies will be in the same instrument. Spectral resolutions spanning the range between 25 and 30,000 can be achieved through the use of iBTF at low resolution and scanning FPs beyond R ~2,000. The third new technologies in BTFI is the use of EMCCDs for rapid and cyclically wavelength scanning thus mitigating the damaging effect of atmospheric variability through data acquisition. An additional important feature of the instrument is that it has two optical channels which allow for the simultaneous recording of the narrow-band, filtered image with the remaining (complementary) broad-band light. This avoids the uncertainties inherent in tunable filter imaging using a single detector. The system was designed to supply tunable filter imaging with a field-of-view of 3 arcmin on a side, sampled at 0.12" for direct Nasmyth seeing-limited area spectroscopy and for SAM's visitor instrument port for GLAO-fed area spectroscopy. The instrument has seen first light, as a SOAR visitor instrument. It is now in comissioning phase.Comment: accepted in PAS

FIREBall-2: advancing TRL while doing proof-of-concept astrophysics on a suborbital platform

Here we discuss advances in UV technology over the last decade, with an emphasis on photon counting, low noise, high efficiency detectors in sub-orbital programs. We focus on the use of innovative UV detectors in a NASA astrophysics balloon telescope, FIREBall-2, which successfully flew in the Fall of 2018. The FIREBall-2 telescope is designed to make observations of distant galaxies to understand more about how they evolve by looking for diffuse hydrogen in the galactic halo. The payload utilizes a 1.0-meter class telescope with an ultraviolet multi-object spectrograph and is a joint collaboration between Caltech, JPL, LAM, CNES, Columbia, the University of Arizona, and NASA. The improved detector technology that was tested on FIREBall-2 can be applied to any UV mission. We discuss the results of the flight and detector performance. We will also discuss the utility of sub-orbital platforms (both balloon payloads and rockets) for testing new technologies and proof-of-concept scientific ideasComment: Submitted to the Proceedings of SPIE, Defense + Commercial Sensing (SI19

FIREBall-2: The Faint Intergalactic Medium Redshifted Emission Balloon Telescope

The Faint Intergalactic Medium Redshifted Emission Balloon (FIREBall) is a mission designed to observe faint emission from the circumgalactic medium of moderate redshift (z~0.7) galaxies for the first time. FIREBall observes a component of galaxies that plays a key role in how galaxies form and evolve, likely contains a significant amount of baryons, and has only recently been observed at higher redshifts in the visible. Here we report on the 2018 flight of the FIREBall-2 Balloon telescope, which occurred on September 22nd, 2018 from Fort Sumner, New Mexico. The flight was the culmination of a complete redesign of the spectrograph from the original FIREBall fiber-fed IFU to a wide-field multi-object spectrograph. The flight was terminated early due to a hole in the balloon, and our original science objectives were not achieved. The overall sensitivity of the instrument and telescope was 90,000 LU, due primarily to increased noise from stray light. We discuss the design of the FIREBall-2 spectrograph, modifications from the original FIREBall payload, and provide an overview of the performance of all systems. We were able to successfully flight test a new pointing control system, a UV-optimized, delta-doped and coated EMCCD, and an aspheric grating. The FIREBall-2 team is rebuilding the payload for another flight attempt in the Fall of 2021, delayed from 2020 due to COVID-19.Comment: 23 Pages, 14 Figures, Accepted for Publication in Ap

Vieillissement - Perspectives sociologiques

International audienc

Le Moyen Âge en Occident

15e éd.International audienc

Des Barbares à la Renaissance

5e édition augmentéeInternational audienc

L'organisation du travail en élevage : Enseigner la méthode bilan travail

La méthode Bilan Travail vise à produire des connaissances sur l'organisation du travail et les temps de travaux en exploitation d'élevage. En situation pédagogique auprès d'élèves de l'enseignement technique, la méthode permet à un groupe de travailler en démarche de projet dans un cadre pluridisciplinaire avec des alternances nécessaires entre apports théoriques, travaux dirigés ou pratiques, et travail personnel. Elle place les apprenants en situation réelle dans le cadre de l'exploitation agricole et mobilise leurs qualités d'observation, d'écoute, de réflexion et d'analyse. Cette méthode est utilisée par des enseignants et formateurs de l'enseignement agricole technique qui l'intègrent dans des modules de formations allant du niveau V au niveau III

&quot;What are you interested in?&quot;-A survey on 601 nursing homes residents activities interests

ABSTRACT Lack of engagement in activities is a common feature of nursing homes residents. As apathy is the most frequent behavioural disturbance, understanding residents&apos; interests is a milestone for tailored challenging interventions targeting engagement enhancement. Objective: To depict the activities interests of nursing homes residents. Method: An electronic version of the Test of Interest &quot;TILT&quot; which regroups 40 images of activities has been developed and adapted for the Ipad. Residents were asked to answer by yes or no to the question &quot;are you interested by this activity&quot;, for each activity found interesting, the patient had then to categorize it in either Work/ occupation-Personal-Leisure-Family. Population: A total of 601 residents from 19 nursing homes have completed the survey from March to May 2011. The surveyed nursing homes from the South East of France were comparable of nursing homes figures in France. Results: We interviewed 601 individuals (female, n = 484) aged 85.9 years, out of those, 56% had stayed more than one year in an institution. Nearly half of the population (45.3%) was from 80 -89 year of age, followed by 36.1% from 90 -99. The educational background was principally from primary school (36%) and high school (30.8%). Most of the residents were classified has having dementia (35.3%). From the 40 activities presented to each participant, &quot;enjoying a good meal&quot; has been found to be the most interesting activity by 83% of the population followed by &quot;dressing up&quot;, 75.9% and &quot;watching TV&quot;, 75.5%. Female participants reported more interest in place of worship, family pictures and being with grand children then males (p &lt; 0.01). We found that the presence of &quot;dementia&quot; diagnosis&quot; triggered the lack of interest compared to none demented or none cognitively impaired residents (p &lt; 0.01). It was found that participants aged 55 -69 were more the most interested to do video games (p &lt; 0.05), though this may be interpreted as a positive step toward functional and cognitive rehabilitation program using virtual reality as a mean for intervention