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Cosmologie@APC (https://apc.u-paris.fr/APC_CS/fr/cosmologie)

Nous voyons ici, du film «Voyage Cosmique» :

Le début homogène de l’univers
L'expansion de l’univers
La recombinaison
Les âges obscurs
la formation des structures dans l'univers

Le groupe de cosmologie de l’APC étudie le début de cette séquence de film à l'aide du fond diffus cosmologique (CMB), et la fin de cette séquence à l'aide de relevés optiques et infrarouges (et aussi le CMB).

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Cosmologie@APC (https://apc.u-paris.fr/APC_CS/en/cosmology)

CMB: L’Univers Primitif

Polarbear /�Simons Array /�Simons Observatory /�CMB Stage 4�
QUBIC�
LiteBIRD

Grand-Champ�Optique/IR�L’Univers “récent”

Rubin / LSST ●

Euclid ●

… plus le CMB à petites échelles ●

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Membres Permanents

Eric Aubourg (Chercheur, HDR)
James Bartlett (PR, HDR)
Alexandre Boucaud (IR-Chercheur; IT)
Martin Bucher (DR, HDR)
Gabriel Chardin (Émerite)
Michel Crézé (Associé)
Josquin Errard (CR)
Ken Ganga (DR, HDR)
Yannick Giraud-Héraud (Émerite)*
Jean-Christophe Hamilton (DR, HDR)
Jean Kaplan (Émerite)

Maxim Khlopov (Benevole)
Sotiris Loucatos (Chercheur)
Simona Mei (PR, HDR)
Guillaume Patanchon (MCF, HDR)
Michel Piat (PR, HDR)
Cyrille Rosset (CR)
Cécile Roucelle (MCF)
Aurore Savoy-Navarro (Émerite)
George Smoot (Émerite)
Radek Stompor (IRL Berkeley)
Steve Torchinsky (IR-Chercheur)

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Jeunes Chercheurs

Doctorants

Anton Afanasiev (Mei)
Biswajit Biswas (Aubourg / Roucelle)
Phạm Việt Dūng (Piat)
Kirill Grishin (Mei)
Baptiste Jost (Stompor / Errard)
Raphael Kou (Bartlett)
Magdy Morshed (Stompor / Errard)
Mathias Regnier (Hamilton)
Arianna Rizzieri (Stompor / Errard)
Wang Wang (Patanchon)
Justine Zeghal (Aubourg / Boucaud)
Zheng Zhang (Bucher)

Post-doctorants

Axel Guinot (Rubin / LSST)
Jie Hu (SPIAKID)
Clément Leloup (LiteBIRD)

Ingénieurs de Recherches

Simon Biquard (CMB)
Rémi Fahed (Euclid)
Jennifer Pollack (Euclid)

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Euclid: probing a deep mystery

Why is the expansion of the Universe accelerating?

Dark energy? Different gravity? Einstein’s biggest mistake/joke?

Euclid’s goal is to answer this question by observing the galaxies and mass in the cosmic web:

Gravitational lensing
Galaxy distribution
Emergence of galaxy clusters

ESA M-class mission�Launch 2024 (? delay due to Soyuz -> Ariane 6)

Telescope: 1.2 m-diameter primary mirror
Two instruments

VIS: Visible imager
NISP: Near-IR imager and slitless spectrograph

6 year mission to map extragalactic sky
Orbit: Earth-Sun Lagrange Point 2 (L2)

Consortium: ~1500 members, >200 laboratories world-wide (Europe, US, Canada, Japan)

https://www.euclid-ec.org/

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Euclid at APC

Team Afanasiev (PhD), Aubourg, Bartlett, Boizard, Boucaud, Cavet, Fahed, Ganga, Kou (PhD), Le Jeune, Mei, Pollack, Ricci (new hire CRCN), Rosset, Roucelle, Souchal, Zappino, IN2P3 Postdoc (9/2022)

Science

Cross-correlations with CMB

Tracing galaxies, gas, and mass in the cosmic web

Galaxy clusters

Dark energy, neutrino mass scale
Proto-clusters, origin of massive structures
Interactions galaxies, gas, and mass

Galaxy evolution

Drivers shaping galaxies

Gravitational lensing

Cosmic shear: dark energy, neutrino mass
Deblending galaxy images

Science Ground Segment (SGS)

Rubin synergy

Rubin data processing in SGS
Rubin simulations in SGS
Euclid-Rubin Derived Data Products

Science-ready products

Cluster galaxy luminosity and mass functions
Cluster selection function

French Science Data Center

CODEEN infrastructure

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LiteBIRD

thermal architecture -- thermal architecture responsibility has been transferred from LESIA to APC in 2021;
instrumental and astrophysical systematic effects, modeling and correction -- APC plays a central role in the modeling, simulations and derivation of calibration requirements. The team is also expert in the modeling, characterization and removal of galactic foregrounds, which are the main limitation to the detection of primordial gravitational waves;
data analysis and cosmological interpretation -- APC is also performing the cosmological analysis on the systematic-corrected and foreground-cleaned CMB maps;
theory --- although not official LiteBIRD members, several APC researchers are studying the performance of LiteBIRD in constraining inflationary or other exotic early Universe scenarios.

Past and present APC members: M. Bucher, J. Errard, K. Ganga, L. Grandsire, J.-Ch. Hamilton, M. Le Jeune, C. Leloup, G. Patanchon, M. Piat, D. Prêle, R. Stompor, J.-P. Thermeau, F. Voisin and W. Wang.

Several APC members are also active members of the Interim Governance Board, co-leading the international systematic Joint Study Group as well as the performance team.

APC participates in many aspects of the mission preparation, such as the foreground subtraction problem, the instrumental effect evaluation and the instrument development:

Japanese mission with strong European involvement.�In particular, CNES is PI of 2 of the 3 instruments.

https://litebird.isas.jaxa.jp/static/eng/

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Activités et faits marquants du projet QUBIC

Envoi de QUBIC TD en Argentine (financement IN2P3):

Départ de Paris Mai 2021; Arrivée à Salta Juillet 2021

Première mise en froid à Salta mi-Août 2021

Plusieurs mises en froid depuis pour :

Régler quelques détails
Former les équipes locales aux opérations avec l’instrument (en visio avec Paris, en particulier avec S. Torchinsky, Deputy Operations Manager)

TD nominal, prêt pour l’installation sur le site�-> Calibrations, Formations équipes
Travaux sur le site: Fondations terminées, restent:

Shelter; Dôme; Electricité

Finalisation attendue fin mai 2022

Installation sur le site prévue pour Juin 2022 ou Octobre 2022 (fct de météo)
Publications: 8 articles acceptés dans JCAP “Special Issue on QUBIC” [LINK]
Financement: situation difficile

10k€ IN2P3 pour 2022,
ERC-Adv-JCH -> “A” en 2020 et 2021 mais sous la barre, resoumise pour 2022 (deadline 28/04)
ANR 2021 -> non sélectionnée à l’issue de la phase 2, resoumise en Mars 2022

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Rubin/LSST

Members of APC mainly involved in the Dark Energy Science Collaboration :

Weak lensing analyses
Cluster studies

A new member will be joining the lab this year (Marina Ricci)

The Vera Rubin Observatory is taking shape see a few picts…

Commissioning�starting 2023

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APC involved on the Filter Control System

F. Virieux - A. Boucaud - E. Aubourg

https://www.lsst.org/

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POLARBEAR/Simons Array | Observatory / CMBS4

CMB-S4 (2031-)

CMB-S4 is the ultimate ground-based CMB observatory, with the deployment of more than half a million detectors
APC is involved in the design optimization, scientific forecast, and management of CMB-S4
Possible hardware contributions, for the warm readout in particular, are being investigated.

APC expertise lies in data analysis: from raw detector data used to get the maps of the sky in each SO frequency to the estimation of cosmological parameters such as the tensor-to-scalar ratio.
Central management roles in the collaboration
Participation to the drone calibration (Labex Emergence)

POLARBEAR (2012-2018)

Simons Array (2020-)

ACT

CLASS

Simons Observatory (2023-)

APC expertise lies in the design optimization and forecast, data analysis and scientific exploitation of the PB/SA data sets

data compression (map-making)
foreground cleaning (e.g. fgbuster)
power spectrum estimation (e.g. Xpure)
cosmological interpretation from SA observations.

9 current members: J. Errard, J. Bartlett, K. Ganga, B. Jost, J.-B. Melin, M. Morshed, A. Rizzieri, S. Biquard, R. Stompor*

6 past: G. Fabbian, J. Peloton, D. Poletti, D. Beck, C. Vergès,� H. El Bouhargani

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May, 2022

Latest news: deployment of SO Small Aperture Telescopes

https://simonsobservatory.org/

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Cosmo VIA

HIRAX

Dirac/Milne Cosmo.

Created in 2006 as an

ASPERA pilot project,�since 2009 it has been�incorporated in the APC �structure. Since 2018

there have been more than 250,000 visits to the site from 153 countries (according to Google Analytics). VIA transmissions of talks at 38 APC Colloquia; Online seminars of APC Theory group; 101 VIA online lectures; Remote presentations from 42 speakers at 15 Conferences; Online XXII, XXIII and XXIV Bled Workshops” What comes beyond the Standard models?” (2019, 2020) Satellite Workshop “A.D.Sakharov’s legacy in Cosmo-particle physics” dedicated to the 100^th Anniversary of A.D. Sakharov (2021) on VIA platform. Open Online Course “Cosmoparticle physics” by M.Khlopov, D.Semikoz, M.Bucher, Fully distant Open Online Exams.

VIA support for webinar, online meetings, sessions and conferences, in particular annual Bled Workshops “What comes beyond the Standard models?”, weekly MRPhI seminars and SFEDU laboratory meetings. Planned books: M.Khlopov, Cosmo-particle physics, 2 Edition, World Scientific, 2023; Indirect effects of dark matter physics, Book review, World Scientific, Ed. M.Khlopov, 2023

HIRAX, a 1024-dish radio telescope array being deployed in the Karoo Desert in South Africa next to the SKA site, will carry out intensity mapping in the 400-800 MHz band, allowing BAOs to be mapped in the redshift range z=0.8-2.5 over a large swath of the Southern sky, allowing Dark Energy to be further constrained. HIRAX will also detect numerous FRBs and new pulsars. Bucher and Zhang are investigating the impact of Faraday-rotated galactic synchrotron emission on intensity mapping science extraction for HIRAX and other experiments. Bucher and Zhang are also in the process of joining the REACH experiment, which will check the claims of Edges to have found an unexpectedly large and unexplained 21cm global signal. These efforts on precursor experiments will help prepare for participation in SKA, in which France has recently become a partner.

Matter-antimatter cosmology, without Dark Matter or Dark Energy

@APC: G. Chardin, in collaboration with G. Manfredi (IPCMS Strasbourg) and P. Ocvirk (CDS, Observatoire de Strasbourg), J-L. Rouet (Univ. Orléans), B. Miller (Univ. Texas), Y. Dubois (IAP Paris)

Recent publications:

G. Manfredi, J-L. Rouet, B. Miller, and G. Chardin (2020): “Structure formation in a Dirac-Milne universe: comparison with the standard cosmological model”, Phys. Rev. D102 (2020) 103518.
G. Chardin, Y. Dubois, G. Manfredi, B. Miller & C. Stahl (2021): “MOND-like behavior in the Dirac–Milne universe”, A&A 652 (2021) A91.

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Calendrier

2019

2020

2021

2022

2023

2024

2025

2026

2027

2028

2029

2030

Euclid

Rubin/LSST

Simons Array

Mi-2024?

1e Données ?

Début d’Obs.

QUBIC

Simons Observatory

CMB Stage 4

LiteBIRD

Lancement