Tools WG session of GDR Cophy

Europe/Paris
Laboratoire d’Astrophysique de Marseille UMR7326 Pôle de l’Étoile Site de Château-Gombert 38, rue Frédéric Joliot-Curie 13388 Marseille CEDEX 13 FRANCE
Description

This working group (website here) is dedicated to raise awareness of new tools and methodology developed in the wider French community to do cosmology. The tools must be understood in a wide sense: it may be large software stack, online websites, or Mathematica© notebook.

This Working Group aims at sharing and helping the development of tools for which the needs are common to all the actors of the GDR.

It includes:

  • tools that are oriented toward the predictions of cosmological observables (including non-linearities) and their relative theoretical systematic uncertainties such as Boltzmann solvers, numerical simulations, approximate methods for the non-linear evolution, and forward modeling,
  • development of estimators for data analysis which are for example based on power spectra, and higher order statistics;
  • mathematical methods for inference such as the one based on MCMC, Machine Learning, and minimizer;
  • production of validation data, such as mock galaxy catalog, mock CMB maps;
  • tools for symbolic-based computation in the cosmological context.

This session is dedicated particularly to the use of Photometric redshift estimator (such as LePhare), Strong lensing image synthesis/analysis, and the use of Manticore (https://cosmictwin.org) data products for cross-correlation analysis.

Lectures will be provided by:

  • Olivier Ilbert and Marie Treyer  (Photometric redshift, Hands on Le Phare)
  • Raphael Gavazzi and Marceau Limousin (Strong lensing)
  • Guilhem Lavaux (Manticore https://cosmictwin.org, Field Level Inference / Cross-correlation with CMB/SNe distances) 

 

We can support the venue of several young researchers: please contact the organizing committee. Also coffee breaks/workshop dinner are included and registration is free (thanks to the support by the GDR Cophy).

The meeting will occur at the LAM:

Laboratoire d’Astrophysique de Marseille
UMR7326
Pôle de l’Étoile Site de Château-Gombert
38, rue Frédéric Joliot-Curie
13388 Marseille CEDEX 13 FRANCE

To reach it from the central train station: subway  line 1, stop at the terminus La Rose and then the bus B3 (2 stops).

The workshop will take place at LAM Amphitheater on ground floor.
 

Coffee breaks will be at LAM, lunches near LAM and dinner on Monday at Novotel Hotel (near Pharo)

Please note that the present timetable is preliminary and slots may be swapped depending on external constraints.

LOC:R.Gavazzi, M.Limousin, M.Treyer, O.Ilbert, N.Martinet, E.Jullo

Tools WG Organizing committee: G.Lavaux, S.Prunet, Y.Rasera

Participants
  • Aurélien Verdier
  • Cristian Carvajal
  • Guilhem Lavaux
  • Laurent MAGRI-STELLA
  • Marceau limousin
  • Marie TREYER
  • Olivier Ilbert
  • Rafael Claudino Arango Toro
  • Raphael Gavazzi
  • Raphael Shirley
  • roland Triay
  • Simon Prunet
  • Wassim Kabalan
  • Yann Rasera
  • +6
  • Monday, November 3
    • Strong Lensing
      • 1
        Scientific context & Strong Lensing formalism
        Speaker: Raphael Gavazzi
      • 2
        Strong lensing lecture
        Speaker: Marceau Limousin
    • 11:15 AM
      Coffee break
    • Strong Lensing
      • 3
        Hans-on Lenstool
        Speaker: Eric Jullo (Aix-Marseille Université / LAM)
      • 4
        Pixel-level source inversion with julia
        Speaker: Raphael Gavazzi
      • 5
        Lenstool
        Speaker: Marceau Limousin
    • Photometric redshift
      • 6
        Photometric redshift
        Speakers: Marie Treyer, Olivier Ilbert
    • 4:00 PM
      Coffee break
    • Photometric redshift
      • 7
        Photometric redshift
        Speakers: Marie Treyer, Olivier Ilbert
  • Tuesday, November 4
    • 10:00 AM
      Coffee
    • Manticore
      • 8
        Cosmology with the Manticore datasets
        Speaker: Guilhem Lavaux (IAP)
    • 9
      Zoom sur les périmètres de l'ATCG

      Lors de la dernière prospective, une discussion sur les périmètres des différentes actions thématiques a été entamée. En particulier, la question s'est posée de maintenir l'ATCG sur les périmètres de l'ancien PNCG (cosmologie et galaxies), ou bien de séparer Cosmologie et Galaxies (ATC et ATG). Cependant, le conseil du PNCG (et la communauté au sens large) n'ayant pas un avis unanime clair, une réflexion plus poussée sur cette possibilité a été remise à plus tard.

      Nous vous proposons un temps de discussion et d'échange sur cette question le mardi 4 novembre à 13h30 par zoom. En particulier, sera présentée une initiative de cosmologistes se proposant de recenser via un sondage les personnes qui souhaiteraient avoir une ATC séparée (et donc deux actions thématiques, ATC et ATG), autour du texte ci-dessous:
      https://docs.google.com/document/d/1AZYbdJIjaeDTVUr7fRPSmjc_ILoXErhTXCINLEKhk3U/edit?tab=t.0

      Pour des raisons d'organisation, si vous souhaitez présenter un court argumentaire (dans un sens ou dans l'autre), merci de l'indiquer à Samuel Boissier (samuel.boissier@lam.fr).

      Les informations de connexion :
      Heure: 4 nov. 2025 01:30 PM Paris
      Participer à la réunion Zoom
      https://univ-amu-fr.zoom.us/j/91086521780?pwd=14WnJg4NtKjT12V3Y8pIu2phquPZUi.1

      ID de réunion: 910 8652 1780
      Code secret: 376880

    • 2:30 PM
      Coffee break
    • Some contributions: Lensing, photometric surveys, simulations etc.
      • 10
        eMANTIS: an accurate emulator for the matter power spectrum and halo mass function in f(R) and wCDM cosmologies
        Speaker: Yann Rasera (LUTH/Université Paris Cité/Observatoire de Paris/IUF)
      • 11
        TBD