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arXiv · 2202.04091

The non-thermal secondary CMB anisotropies from a cosmic distribution of radio galaxy lobes

Sandeep Kumar Acharya·Subhabrata Majumdar·Biman B. Nath
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Abstract

Current and upcoming high angular resolution and multi-frequency experiments are well poised to explore the rich landscape of secondary CMB anisotropies. In this context, we compute for the first time, the power spectrum of CMB fluctuations from a cosmological distribution of evolving lobes of giant radio galaxies. We, also, explicitly take into account the non-thermal electron distribution, which has important implications for the inference of the CMB angular power spectrum. We calculate the mean global non-thermal y-distortion, \ynt. For observationally reasonable distribution of the jet luminosities in the range of $10^{45}-10^{47}$ ergs$^{-1}$, we find \ynt to be less than $10^{-5}$, and hence not violating the COBE limit as previously claimed. Using the unique spectral dependence of the non-thermal SZ, we show that a detection of \ynt can be within reach at the level of $\gtrsim 5σ$ from a future PIXIE-like experiment provided we understand the foregrounds precisely. The total non-thermal SZ power spectrum, $C^{NT}_\ell$, from the radio lobes peaks at $\ell \sim 3000$ with an amplitude $\sim 1\%$ of thermal SZ power spectrum from galaxy clusters. A a detection of the $C^{NT}_\ell$, with a PIXIE-like sensitivity experiment, can lead to $\sim 5σ$ constraint on the mass dependence of the jet luminosity with the constraint becoming, at least, ten times better for the proposed more ambitious CMB-HD survey. This will, further, lead to the tightest constrain on the central black hole mass -to- host halo mass scaling relations.

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Sandeep Kumar Acharya, Subhabrata Majumdar, Biman B. Nath. 2022-11-04. The non-thermal secondary CMB anisotropies from a cosmic distribution of radio galaxy lobes. https://doi.org/10.1093/mnras%2Fstac3166

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