Search results for "snr"

The outer shock of SN1006

2008

Hydrodynamic modeling of ejecta shrapnels in the Vela SNR

2008

Modeling SNR shock waves expanding through the magnetized inhomogeneous interstellar medium

2009

We review our recent results on the MHD modeling of supernova shock waves propagating through the magnetized and inhomogeneous ISM. We explore the role of different physical processes simultaneously at work, namely magnetic-field-oriented thermal conduction, radiative cooling and MHD effects, in determining: 1) the mass and energy exchanges between different phases of the ISM and 2) the morphology of supernova remnants as observed in different bands. Our projects required an advanced 3D MHD code for parallel computers, FLASH, and high-performance computing. We discuss the results derived from the analysis of the local interaction of strong shocks with inhomogeneities of the ISM, and those d…

Signal to Noise Ratio of Silicon Photomultipliers: a study in the Continuous Wave Regime

2014

We report on Signal to Noise Ratio measurements carried out, in the continuous wave regime, at different bias voltages, frequencies and temperatures, on a novel class of silicon photomultipliers fabricated in planar technology on silicon p-type substrate. Signal to Noise Ratio has been measured as the ratio of the photogenerated current, filtered and averaged by a lock-in amplifier, and the Root Mean Square deviation of the same current. The measured noise takes into account the shot noise, resulting from the photocurrent and the dark current. We have also performed a comparison between our SiPMs and a photomultiplier tube in terms of Signal to Noise Ratio, as a function of the temperature …

Indications of a Si-rich bilateral jet of ejecta in the Vela SNR observed with XMM-Newton

2017

Context. The Vela supernova remnant displays several ejecta, which are fragment-like features protruding beyond the front of its primary blast shock wave. They appear to be "shrapnel", bowshock-shaped relics of the supernova explosion. One of these pieces of shrapnel (A), located in the northeastern edge of the remnant, is peculiar because its X-ray spectrum exhibits a high Si abundance, in contrast to the other observed ejecta fragments, which show enhanced O, Ne, and Mg abundances. Aims. In this Letter we present the analysis of another ejecta fragment located opposite to shrapnel A with respect to the center of the shell, in the southwestern boundary of the remnant, named shrapnel G. We …

Shock-cloud interaction in the Vela SNR: the XMM-Newton view

2004

B-MINE, the balloon-borne microcalorimeter nuclear line explorer

2001

B-MINE is a concept for a balloon mission designed to probe the deepest regions of a supernova explosion by detecting Ti-44 emission at 68 keV with spatial and spectral resolutions that are sufficient to determine the extent and velocity distribution of the Ti-44 emitting region. The payload introduces the concept of focusing optics and microcalorimeter spectroscopy to nuclear line emission astrophysics. B-MINE has a thin, plastic foil telescope multilayered to maximize the reflectivity in a 20 keV band centered at 68 keV and a microcalorimeter array optimized for the same energy band. This combination provides a reduced background, an energy resolution of 50 eV and a 3sigma sensitivity in …

GAPDH, ntosak and cdc48, a conserved chaperone-like aaa-atpase, as nitric oxide targets in response to (a)biotic stresses

2013

ABA-independent SnRK2 kinases are involved in plant response to salinity

2013

Un poster a été présenté lors de cet événement SPE IPM CT non renseigné car non soutenu par INRA; International audience; Sucrose non-fermenting 1-Related Protein Kinases type 2 family (known as SnRK2) are important group of kina- ses present in all tested plant species. It is known that all SnRK2 (excluding SnRK2.9) are activated in response to salinity and hyperosmolarity in Arabidopsis thaliana protoplasts after short time of treatment. In plants, they are in- volved in the early responses to drought and salinity. Recently published data indicate that SnRK2.4 plays important role in the maintenance of root system architecture during salt stress and in response to cadmium treatment. It wa…

Trans-cranial Magnetic Resonance-guided Focused UltraSound (tcMRgFUS) system integrated with a 1.5T: an SNR study on DQA phantoms

2018

Background: In recent years transcranial Magnetic Resonance-guided Focused Ultrasound Surgery (tcMRgFUS) treatments have been performed only using 3T units. Since following some internal analysis, planning images obtained using a 1.5T MRI’s body RF coil (as usually done with 3T systems) showed generally reasonable quality in terms of anatomy visualization and SNR but thermal images noise was above acceptable standard for treatments, a dedicated 2-channels head coil was developed (InSightec Ltd.) to ensure an adequate signal-to-noise ratio (SNR). Hence, we present the imaging protocol and the technological methods successfully used with the world-first installation of a certified tcMRgFUS sy…