Colloque national CMB-France #7

Session

Future missions

14 oct. 2025, 14:00

Institut Astrophysique de Paris

36. Towards the measurement of spectral distortions from space: from BISOU to FOSSIL

Nabila Aghanim

14/10/2025 14:00

Both standard and non-standard physics processes inevitably lead to distortions of the CMB black-body shape. They provide a unique opportunity to reveal a novel tracer of the early Universe, particle physics and structure formation. The presentation will cover some of the ongoing efforts in BISOU (Cnes Balloon project) and FOSSIL (ESA M8 proposal) to design and fly a future satellite aimed at...

22. The BISOU optical concept design

Morgane LOQUET LE GALL (IAS)

14/10/2025 14:20

The last and only measurement of the CMB spectrum was performed by COBE-FIRAS in 1991, showing that it is close to a perfect blackbody emission. However, deviations referred to as CMB spectral distortions are expected. Due to its limited sensitivity, FIRAS could only give upper limits, leading to new space missions being proposed to perform this measurement. The balloon-borne mission BISOU...

33. Optimisation and Forecasting Studies for CMB Spectral Distortion Experiments

Xavier COULON (IAS)

14/10/2025 14:40

In the 1990s, the COBE/FIRAS mission measured the Cosmic Microwave Background (CMB) spectrum and demonstrated that its spectral energy distribution is extremely close to a perfect blackbody. However, theory shows that tiny departures from a black body are expected at the level of $\Delta I/I \simeq 10^{-5}$, known as spectral distortions. The two main types of CMB spectral distortions are the...

29. LiteBIRD status

Ludovic Montier (IRAP)

14/10/2025 15:00

I will present the current status of the LiteBIRD JAXA mission, after it entered in reformation period since September 2024, and recently went through a key review at JAXA in September 2025.

15. Probing Inflation with PICO: Iterative internal lensing reconstruction and delensing pipeline on a full-sky mission with realistic noise and foregrounds

Julien Tang (LBNL/CPB)

14/10/2025 15:20

Unambiguously detecting the primordial gravitational waves signal requires precise subtraction of confounding foregrounds, which have much larger amplitude. One such foreground is B-modes generated by gravitational lensing of E-modes.

We validated an optimal map-based delensing pipeline on simulations, with different complexities of noise including white and 1/f noise, homogeneous and...

14. Impact of realistic noise and foregrounds on r forecasts for PICO

Elisa Russier

14/10/2025 15:40

The Probe of Inflation and Cosmic Origins (PICO) is a space mission submitted to the Astro2020 Decadal Review as an inflation probe. In a previous paper (Aurlien et al, 2023), the PICO team demonstrated performance based on simplifying assumptions, in particular, white homogeneous noise. We present updated r forecasts, based on end-to-end simulations, for a realistic noise including...

1. Status and future plans for the South Pole Observatory (SPO)

Clara Vergès (LBNL)

14/10/2025 16:30

The South Pole Observatory (SPO) brings together the BICEP and SPT collaborations with the goal of providing state-of-the-art constraints on inflationary gravitational waves. The BICEP program has a long history of setting constraints on the tensor-to-scalar ratio r, including the current leading constraint $\sigma(r) = 0.009$ (PRL, 2021). Future results will benefit from the increased...

37. KAIROS

Dr Josquin Errard (APC / CNRS)

14/10/2025 16:50

The proposal to build a high-frequency Small Aperture Telescope (SAT) as a new component of the Simons Observatory has gained increasing momentum over the recent years. This initiative, named KAIROS, is under evaluation for funding through the CNRS RI² program (“Recherche à risque et à impact”), with the backing of three CNRS institutes: IN2P3, INSU, and INP.

KAIROS aims to deploy a focal...