A measurement of the millimetre emission and the Sunyaev–Zel'dovich effect associated with low-frequency radio sources
We present a statistical analysis of the millimetre-wavelength properties of 1.4 GHz-selected sources and a detection of the Sunyaev–Zel'dovich (SZ) effect associated with the haloes that host them. We stack data at 148, 218 and 277 GHz from the Atacama Cosmology Telescope at the positions of a large sample of radio AGN selected at 1.4 GHz. The thermal SZ effect associated with the haloes that host the AGN is detected at the 5σ level through its spectral signature, representing a statistical detection of the SZ effect in some of the lowest mass haloes (average M_(200) ≈ 10^(13) M⊙ h^(−1)_(70) studied to date. The relation between the SZ effect and mass (based on weak lensing measurements of radio galaxies) is consistent with that measured by Planck for local bright galaxies. In the context of galaxy evolution models, this study confirms that galaxies with radio AGN also typically support hot gaseous haloes. Adding Herschel observations allows us to show that the SZ signal is not significantly contaminated by dust emission. Finally, we analyse the contribution of radio sources to the angular power spectrum of the cosmic microwave background.
Additional Information© 2014 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. Accepted 2014 August 4. Received 2014 August 4; in original form 2013 October 30. First published online September 29, 2014. This work was supported by the US National Science Foundation through awards AST-0408698 and AST-0965625 for the ACT project, as well as awards PHY-0855887 and PHY-1214379. Funding was also provided by Princeton University, the University of Pennsylvania, and a Canada Foundation for Innovation (CFI) award to UBC. ACT operates in the Parque Astronómico Atacama in northern Chile under the auspices of the Comisión Nacional de Investigación Científica y Tecnológica de Chile (CONICYT). Computations were performed on the GPC supercomputer at the SciNet HPC Consortium. SciNet is funded by the CFI under the auspices of Compute Canada, the Government of Ontario, the Ontario Research Fund – Research Excellence; and the University of Toronto. MBG and TAM acknowledge support from Johns Hopkins University. RD, PA, FR and GM received funding from the Chilean grants FONDECYT 11100147 and BASAL (CATA). This research made use of ASTROPY, a community-developed core PYTHON package for Astronomy (Astropy Collaboration 2013).
Published - MNRAS-2014-Gralla-460-78.pdf
Submitted - 1310.8281v2.pdf