Delay interferometric single-shot measurement of a petawatt-class laser longitudinal chromatism corrector

International audienceIn this paper we present a self-referenced interferometric single-shot measurement technique that we use to evaluate the longitudinal chromatism compensation made by a diffractive lens corrector. A diffractive lens with a delay of 1 ps is qualified for a 60 mm beam aperture. This corrector was implemented on the Alisé Nd:glass power chain. We qualify the corrector and the Alisé power chain chromatism, demonstrating the potential of this measuring principle as well as the interest of diffractive lenses to correct longitudinal chromatism of petawatt-class lasers

Introduction à la physique du laser

École thématiqu

Resurrecting the alien director: Jean-Pierre Jeunet in Hollywood

This essay examines the critical reception of Jean-Pierre Jeunet's Alien Resurrection in the popular Anglo-American press, where the film was often discussed in terms that highlighted the director's status as an 'outsider'. The anxiety that the film elicits among critics, it is argued, is a function of the very abjection that is depicted graphically within the film: a fear of the unclassifiable and of the crossing of boundaries

Decorated vertices with 3-edged cells in 2D foams: exact solutions and properties

The energy, area and excess energy of a decorated vertex in a 2D foam are calculated. The general shape of the vertex and its decoration are described analytically by a reference pattern mapped by a parametric Moebius transformation. A single parameter of control allows to describe, in a common framework, different types of decorations, by liquid triangles or 3-sided bubbles, and other non-conventional cells. A solution is proposed to explain the stability threshold in the flower problem.Comment: 13 pages, 17 figure

Data and initial model set-up for the 2022 VPA stock assessment of the eastern Atlantic and Mediterranean bluefin tuna

This document presents the data and initial model set-up for the 2022 Stock Assessment for the Eastern Atlantic and Mediterranean bluefin tuna stock. During the 2017 Data Preparatory meetings, several changes in the data used for previous assessments have been presented, among which the revision of the Task 1 and Task 2 statistics and the selection of the indices of abundance. This led to completely revisiting the catch at age matrix and the model specifications for the 2017 assessment. For the present document, the data over the historical period (1968-2015) were nearly identical, whereas the data for the years 2016-2020 and abundance indices were updated. As agreed in previous meetings, the initial model specifications were kept identical to the 2017 assessment as no change has been agreed on since then

Final data, explorations, model set-up and diagnostics for the 2022 VPA stock assessment of the eastern and Mediterranean Atlantic bluefin tuna stock

This document presents the modeling work done for the 2022 stock assessment for the Eastern and Mediterranean Bluefin tuna stock, during informal modeling subgroup meetings in June 2022. This document presents various runs built upon the base case for the 2017 stock assessment. These runs aim at addressing issues identified in the 2020 update assessment and aspects discussed during the informal meetings held in june 2022, regarding the inclusion of updated catch at age data, improvement of model stability in relation to Fratio estimates, the selection of the age for the plus group, inclusion of the WMED_GBYP_AER index. Following several explorations, the present work contains two runs that displayed improved diagnostics compared to previous runs. These models have improved retrospective patterns and no problematic issue was found through jittering the random number generator, jittering the starting values for the terminal F estimate, bootstrapping or through jackknife analysis

Review of the catch and catch-at-age estimation for the E-BFT catch inflated estimates 1998-2007

During the 2022 Eastern Atlantic and Mediterranean Bluefin Tuna Data Preparatory Meeting, the Bluefin Species Group (BFTSG) agreed to revise the assumptions and update the catch-atsize/catch-at-age (CAS/CAA) intersessionally by replacing the "NEI (inflated)" partial catches component (1998-2007) with a new set of combined Mediterranean size samples. An ad-hoc small group was formed to carry out this task and proposed an alternative CAS/CAA for the 2022 E-BFT stock assessment, this document summarizes these analyses. This document provides the revised CAS (version 2b), and two CAA based on the von Bertalanffy and the Richards growth curves. The small group agreed that this revised CAS is a better estimate of the size distribution for the NEI-inflated catch and proposed to be adopted by the BFTSG, and aso recommended that this revision would be applied only to VPA (Virtual Population Analysis) and possibly ASAP (Age Structured Assessment Program)

Report of the 11th Liaison Meeting

The   11thLiaison   Meeting   between   the   Chairs   of   the   RCMs,   the   ICES   PGCCDBS,   PGMED  and  PGECON,  the  STECF  EWGs  on  the  DCF,  the  Regional  Database  Steering   Committees,  the  ICES  and  GFCM  representatives  and  the  European  Commission  was   held  at  the  DG  Maritime  Affairs  and  Fisheries,  Brussels  from  8th  to  9th  October  2014. The  11th  Liaison  meeting  was  held  in  Brussels  on  8th  and  9th  October  2014  to  address  the   following  terms  of  reference:     TOR  1.  Discussion  on  possible  follow-­‐‑up  to  the  main  outputs/recommendations  of:   • The  2014  RCMs  and  to  the   sp ecific  re commenda tions  a ddr e sse d  to  th e  Liaison   Meeting   • P G ECO N ,  PG CCDBS,  PG Med   –   ou tcome s  an d  r e commendation s  fr om  the ir   2014  meeting     • STECF  EWG  and  STEC F  Plen ary   -­‐‑   ou tcome s  a n d  r e commendation s  fr om  the ir   2014  meeting     • Data  end-­‐‑ users  (IC ES,  G F C M,  RC Ms)   TOR  2.  Compilation  of  recommendations  on  the  DCF   A  compilation  of  DCF  recommendations  will  be  established  by  the  COM  by  end  2014.   LM   needs   to   agree   on   which   recommendations   should   be   included   (i.e.   from   which   bodies)  &  covering  which  years.     TOR  3.  Regional  cooperation   • G r ants  for  str eng thene d  reg ion al  coop eration     • R e g ional  da ta b ases   o O ver view  of  use  of  the  Reg ional  Datab ases  for  R CMs  in  2014,  and  p rob lems   identified   o O ther  deve lop ments  (RDB  training s  in  2014,  RDB  Med&BS  develop ment)   o Chang es  for  the  fu tu re   –  an y  re commen da tions  from  th e  LM?   • R C M  data  calls   –  ove rview  of  h ow  MS  r esp onde d.   TOR  4.  Recommended  meetings/workshops   • P r ep a r e  a  list  of  r ecommen ded  me etin g s  for  2015  as  g u idance  for  MS   TOR  5.  Studies   • O ver view  of  p rocess   • LM  comme nts  and  p r ioritization  of  studies  p r op osed  b y  RC Ms,  PG ECO N ,  ICES,   GFCM   TOR  6.  AOB     1. The  DCF  website  has  been  revamped  by  the  JRC.  Any  comments  on  this?   2. Access  to  the  RCM  SharePoint   3. Derogations  –  List  of  derogations  by  Member  State  has  been  prepared  by  DG   MARE.  Have  any  RCMs  updated  this?     4. ICES  will  provide  an  update  on  their  plans  to  re-­‐‑evaluate  surveys.  Should  this   be  followed  by  STECF  work  on  surveys  to  be  included  in  future  EU  MAP?   5. Annual  reports  –  simplification:  presentation  of  process. 6. Data  transmission:   a. new   platform   for   information   exchanges   between   COM,   MS   and   end-­‐‑ users   b. new   tool   for   reporting   on   how   MS   complied   with   the   DG   MARE/JRC   data  calls     In   addition   to   the   above   Terms   of   Reference,   an   item   was   added   at   the   start   of   the   meeting,  regarding  the  implication  of  the  Landing  Obligation  on  data  collection  and   the  Discard  Plans.

Non-Gaussian Velocity Distribution Function in a Vibrating Granular Bed

The simulation of granular particles in a quasi two-dimensional container under the vertical vibration as an experimental accessible model for granular gases is performed. The velocity distribution function obeys an exponential-like function during the vibration and deviates from the exponential function in free-cooling states. It is confirmed that this exponential-like distribution function is produced by Coulomb's friction force. A Langevin equation with Coulomb's friction is proposed to describe the motion of such the system.Comment: 4 pages, 4 figures. to be published in Journal of Physical Society of Japan Vol.73 No.