The guider and wavefront curvature sensor subsystem for the Large Synoptic Survey Telescope

The Large Synoptic Survey Telescope instrument include four guiding and wavefront sensing subsystems called corner raft subsystems, in addition to the main science array of 189 4K x 4K CCDs. These four subsystems are placed at the four corners of the instrumented field of view. Each wavefront/guiding subsystem comprises a pair of 4K x 4K guide sensors, capable of producing 9 frames/second, and a pair of offset 2K x 4K wavefront curvature sensors from which the images are read out at the cadence of the main camera system, providing 15 sec integrations. These four guider/wavefront corner rafts are mechanically and electrically isolated from the science sensor rafts and can be installed or removed independently from any other focal plane subsystem. We present the implementation of this LSST subsystem detailing both hardware and software development and status.Astronom

LSST: from Science Drivers to Reference Design and Anticipated Data Products

(Abridged) We describe here the most ambitious survey currently planned in the optical, the Large Synoptic Survey Telescope (LSST). A vast array of science will be enabled by a single wide-deep-fast sky survey, and LSST will have unique survey capability in the faint time domain. The LSST design is driven by four main science themes: probing dark energy and dark matter, taking an inventory of the Solar System, exploring the transient optical sky, and mapping the Milky Way. LSST will be a wide-field ground-based system sited at Cerro Pach\'{o}n in northern Chile. The telescope will have an 8.4 m (6.5 m effective) primary mirror, a 9.6 deg$^2$ field of view, and a 3.2 Gigapixel camera. The standard observing sequence will consist of pairs of 15-second exposures in a given field, with two such visits in each pointing in a given night. With these repeats, the LSST system is capable of imaging about 10,000 square degrees of sky in a single filter in three nights. The typical 5$\sigma$ point-source depth in a single visit in $r$ will be $\sim 24.5$ (AB). The project is in the construction phase and will begin regular survey operations by 2022. The survey area will be contained within 30,000 deg$^2$ with $\delta<+34.5^\circ$, and will be imaged multiple times in six bands, $ugrizy$, covering the wavelength range 320--1050 nm. About 90\% of the observing time will be devoted to a deep-wide-fast survey mode which will uniformly observe a 18,000 deg$^2$ region about 800 times (summed over all six bands) during the anticipated 10 years of operations, and yield a coadded map to $r\sim27.5$. The remaining 10\% of the observing time will be allocated to projects such as a Very Deep and Fast time domain survey. The goal is to make LSST data products, including a relational database of about 32 trillion observations of 40 billion objects, available to the public and scientists around the world.Comment: 57 pages, 32 color figures, version with high-resolution figures available from https://www.lsst.org/overvie

Les biotechnologies (la planche de salut de l'industrie pharmaceutique ?)

Dans les années 1980, la naissance de la biotechnologie a bouleversé l'industrie du médicament. L'industrie des biotechnologies (biotech) a apporté une rupture dans le modèle d'innovation et dans les technologies utilisées. Aujourd'hui, la reconfiguration qui s'opère dans l'industrie pharmaceutique est fortement influencée par ce bouleversement. Ce que certains appellent le virage biotech devient une nécessité croissante pour les laboratoires pharmaceutiques. Dans le but de comprendre ces nouveaux enjeux, nous réalisons une revue historique de l'émergence de l'industrie biotech et du développement de l'industrie pharmaceutique. Nous étudions ainsi ce qui distingue ces deux industries. Dans un deuxième temps, nous montrons comment l'industrie classique des Big Pharma intègre progressivement le modèle biotech poussée par le déclin de son modèle traditionnel. Cette analyse nous permet de décrypter les évolutions actuelles dans l'industrie du médicament et de définir les facteurs clés de succès du développement des traitements innovants de demain, qui tiennent à la fois au progrès scientifique dans les sciences de la vie et à des transformations dans l'organisation de la recherche et du développement des médicaments. Enfin sous cet éclairage et à titre d'exemple, nous analysons la stratégie du groupe Sanofi et le rachat récent de la société de biotechnologies GenzymeLYON1-BU Santé (693882101) / SudocSudocFranceF

High-speed nuclear quality pulse height analyzer for synchrotron-based applications

A high throughput Pulse Height Analyzer system for synchrotron-based applications requiring high resolution, high processing speed and low dead time has been developed. The system is comprised of a 120ns 12-bit nuclear quality Analog to Digital converter with a self-adaptive fast peak detector-stretcher and a custom-made fast histogramming memory module that records and processes the digitized data. The histogramming module is packaged in a VME or VXI compatible interface. Data is transferred through a fast optical link from the memory interface to a computer. A dedicated data acquisition program matches the hardware characteristics of the histogramming memory module. The data acquisition system allows for two data collection modes: ''standard'' data acquisition mode where the data is accumulated and read in synchronization with an external trigger and ''live'' data acquisition mode where the system operates as a standard Pulse Height Analyzer. The acquisition, standard or live, can be performed on several channels simultaneously. A two-channel prototype has been demonstrated at the Stanford Synchrotron Radiation Laboratory accelerator in conjunction with an X-ray Fluorescence Absorption Spectroscopy experiment. A detailed description of the entire system is given and experimental data is shown

High-speed nuclear quality pulse height analyzer for synchrotron-based applications

A high throughput Pulse Height Analyzer system for synchrotron-based applications requiring high resolution, high processing speed and low dead time has been developed. The system is comprised of a 120ns 12-bit nuclear quality Analog to Digital converter with a self-adaptive fast peak detector-stretcher and a custom-made fast histogramming memory module that records and processes the digitized data. The histogramming module is packaged in a VME or VXI compatible interface. Data is transferred through a fast optical link from the memory interface to a computer. A dedicated data acquisition program matches the hardware characteristics of the histogramming memory module. The data acquisition system allows for two data collection modes: ''standard'' data acquisition mode where the data is accumulated and read in synchronization with an external trigger and ''live'' data acquisition mode where the system operates as a standard Pulse Height Analyzer. The acquisition, standard or live, can be performed on several channels simultaneously. A two-channel prototype has been demonstrated at the Stanford Synchrotron Radiation Laboratory accelerator in conjunction with an X-ray Fluorescence Absorption Spectroscopy experiment. A detailed description of the entire system is given and experimental data is shown

The Space-based Telescopes for Actionable Refinement of Ephemeris (STARE) mission

Recent events, such as the February 2009 Iridium 33-Cosmos 2251 collision, have brought attention to the changing nature of the Low Earth Orbit (LEO) environment. The population of objects recorded by the US Space Catalog has doubled since 1992, resulting in an increased risk of on-orbit collisions. USSTRATCOM’s Space Surveillance Network (SSN) tracks resident space objects (RSO) and publicly releases a subset of these data to support conjunction (collision probability) analyses. However, these early warning systems did not prevent the Iridium – Cosmos collision. Conversely, there have been a number of high profile ISS false alarms where the crew has unnecessarily interrupted operations to take shelter. These examples highlight the need for better Space Situational Awareness (SSA) in LEO. The Space-based Telescopes for Actionable Refinement of Ephemeris (STARE) mission will improve SSA using a low-cost small satellite constellation. An operational STARE constellation of 18 nanosatellites will be able to assess greater than 99% of all conjunctions involving objects larger than 10 cm and has the capability to reduce the current collision false alarm rate by two orders of magnitude up to 24 hours ahead of closest approach, in effect reducing the number of actionable alerts to one per satellite lifetime. This is a significant improvement over today’s capability, which provides so many false alarms (estimated at one per month per satellite for a LEO sun-synchronous orbit) that alerts are regularly ignored due to the inability of the space assets to move frequently

Government-owned CubeSat Next Generation Bus Reference Architecture

The number of CubeSats and small satellites placed in orbit has been growing exponentially since 1999 as demonstrated by more than 40 CubeSats being launched in the last quarter of 2013 from the USA alone. While CubeSats were initially used for academic purpose and generally tailored towards technology demonstration, it has become more evident that small satellites can play a role in some operational contexts such as earth observation, space weather, or situational awareness, to name just a few. In the past, each institution involved in Small Satellites has often designed their own proprietary system with regards to communication, software, avionics, and command and control, with incremental improvements based on previous successes. While this may make sense in an academic environment, where it provides students with a wide range of learning opportunities, it distracts teams exploring scientific or operational missions from focusing primarily on the payload technology. Building upon previous work funded by the National Reconnaissance Office (NRO) and known as the Colony I and Colony II bus programs, the Lawrence Livermore National Laboratory (LLNL), in partnership with the Naval Postgraduate School (NPS) is developing a CubeSat bus reference architecture and a set of minimum specifications useful for government applications. The architecture has application to software, electrical, and mechanical interfaces and aims at providing a flexible platform that can be endorsed by industry, supporting interchangeability of components while retaining customization for payload integration. We intend to present the framework of the architecture and its first embodiment in a flat satellite prototype

Hydrogen for maritime application—quality of hydrogen generated onboard ship by electrolysis of purified seawater

Maritime transport is investigating several options to reduce its greenhouse gases and air pollutant emissions. An experimental ship, Energy Observer, is using excess renewable energy to generate onboard hydrogen by electrolysis of purified seawater. As a promising option for storing energy, it can provide on-demand energy to the ship through a hydrogen fuel cell (FC). As hydrogen FCs lifetime and performance are correlated to hydrogen quality, the hydrogen produced onboard needs to be monitored. This study assesses the probability of contaminants presence for this electrolyser, using purified seawater and supports the results with a hydrogen fuel quality analysis from the Energy Observer ship. It demonstrates that an electrolyser using onboard purified seawater can generate hydrogen of a quality compliant with ISO 14687:2019. Additional contaminants (i.e., ions, heavy metal) were also measured. The study highlights the potential contaminants to be monitored and future research on new contaminants from seawater to further develop hydrogen fuel for maritime applications

Hydrogen for maritime application—Quality of hydrogen generated onboard ship by electrolysis of purified seawater

International audienceMaritime transport is investigating several options to reduce its greenhouse gases and air pollutant emissions. An experimental ship, Energy Observer, is using excess renewable energy to generate onboard hydrogen by electrolysis of purified seawater. As a promising option for storing energy, it can provide on-demand energy to the ship through a hydrogen fuel cell (FC). As hydrogen FCs lifetime and performance are correlated to hydrogen quality, the hydrogen produced onboard needs to be monitored. This study assesses the probability of contaminants presence for this electrolyser, using purified seawater and supports the results with a hydrogen fuel quality analysis from the Energy Observer ship. It demonstrates that an electrolyser using onboard purified seawater can generate hydrogen of a quality compliant with ISO 14687:2019. Additional contaminants (i.e., ions, heavy metal) were also measured. The study highlights the potential contaminants to be monitored and future research on new contaminants from seawater to further develop hydrogen fuel for maritime applications

A 4 U Laser Heterodyne Radiometer for Methane (CH4) and Carbon Dioxide (CO2) Measurements from an Occultation-Viewing CubSat

We present a design for a 4 U (20 cm 20 cm 10 cm) occultation-viewing laser heterodyne radiometer (LHR) that measures methane (CH4), carbon dioxide (CO2) and water vapor(H2O) in the limb that is designed for deployment on a 6 U CubeSat. The LHR design collects sunlight that has undergone absorption by the trace gas and mixes it with a distributive feedback (DFB) laser centered at 1640 nm that scans across CO2, CH4, and H2O absorption features. Upper troposphere lower stratosphere measurements of these gases provide key inputs to stratospheric circulation models: measuring stratospheric circulation and its variability is essential for projecting how climate change will affect stratospheric ozone