Jul 5 – 10, 2021
Europe/Rome timezone

Prospect for WHIM detection in the cosmic web by SRG/eROSITA

Jul 6, 2021, 10:30 AM
Talk in the parallel session The SRG Mission: First Results from eROSITA and ART-XC The SRG Mission: First Results from eROSITA and ART-XC


Hideki Tanimura (L'Institut d'Astrophysique Spatiale (IAS))Dr Nabila Aghanim (Institut d'Astrophysique spatiale)


Hydrodynamical simulations predict that the cosmic web contains the majority of the missing baryons in the form of plasma, called the warm-hot intergalactic medium (WHIM). However, its direct measurement through X-ray emission has been prevented for decades due to the weakness of the signal and to the complex morphology of cosmic filaments.

We identified more than 15,000 large-scale filaments, spanning 30-100 Mpc length, in the SDSS survey and statistically detected the X-ray emission from the WHIM at ~4 sigma confidence level using the ROSAT and Planck data. We expect a much more significant detection from SRG/eROSITA. We indeed predicted the detectability to the WHIM. The prediction shows that stacking ∼2000 filaments only would lead to a 5σ detection with an average gas temperature of the WIHM as low as ~0.3 keV.

Primary authors

Hideki Tanimura (L'Institut d'Astrophysique Spatiale (IAS)) Dr Nabila Aghanim (Institut d'Astrophysique spatiale)

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