TY - JOUR
T1 - Dissecting the thermal Sunyaev-Zeldovich-gravitational lensing cross-correlation with hydrodynamical simulations
AU - Hojjati, Alireza
AU - McCarthy, Ian G.
AU - Harnois-Deraps, Joachim
AU - Ma, Yin-Zhe
AU - Van Waerbeke, Ludovic
AU - Hinshaw, Gary
AU - Le Brun, Amandine M. C.
PY - 2015/10/21
Y1 - 2015/10/21
N2 - We use the cosmo-OWLS suite of cosmological hydrodynamical simulations,
which includes different galactic feedback models, to predict the
cross-correlation signal between weak gravitational lensing and the
thermal Sunyaev-Zeldovich (tSZ) y-parameter. The predictions are
compared to the recent detection reported by van Waerbeke and
collaborators. The simulations reproduce the weak lensing-tSZ
cross-correlation, ξyκ(θ), well. The
uncertainty arising from different possible feedback models appears to
be important on small scales only (0θ lesssim 1 arcmin), while
the amplitude of the correlation on all scales is sensitive to
cosmological parameters that control the growth rate of structure (such
as σ8, Ωm and Ωb).
This study confirms our previous claim (in Ma et al.) that a significant
proportion of the signal originates from the diffuse gas component in
low-mass (Mhalo lesssim 1014 Msolar)
clusters as well as from the region beyond the virial radius. We
estimate that approximately 20% of the detected signal comes from
low-mass clusters, which corresponds to about 30% of the baryon density
of the Universe. The simulations also suggest that more than half of the
baryons in the Universe are in the form of diffuse gas outside halos
(gtrsim 5 times the virial radius) which is not hot or dense enough to
produce a significant tSZ signal or be observed by X-ray experiments.
Finally, we show that future high-resolution tSZ-lensing
cross-correlation observations will serve as a powerful tool for
discriminating between different galactic feedback models.
AB - We use the cosmo-OWLS suite of cosmological hydrodynamical simulations,
which includes different galactic feedback models, to predict the
cross-correlation signal between weak gravitational lensing and the
thermal Sunyaev-Zeldovich (tSZ) y-parameter. The predictions are
compared to the recent detection reported by van Waerbeke and
collaborators. The simulations reproduce the weak lensing-tSZ
cross-correlation, ξyκ(θ), well. The
uncertainty arising from different possible feedback models appears to
be important on small scales only (0θ lesssim 1 arcmin), while
the amplitude of the correlation on all scales is sensitive to
cosmological parameters that control the growth rate of structure (such
as σ8, Ωm and Ωb).
This study confirms our previous claim (in Ma et al.) that a significant
proportion of the signal originates from the diffuse gas component in
low-mass (Mhalo lesssim 1014 Msolar)
clusters as well as from the region beyond the virial radius. We
estimate that approximately 20% of the detected signal comes from
low-mass clusters, which corresponds to about 30% of the baryon density
of the Universe. The simulations also suggest that more than half of the
baryons in the Universe are in the form of diffuse gas outside halos
(gtrsim 5 times the virial radius) which is not hot or dense enough to
produce a significant tSZ signal or be observed by X-ray experiments.
Finally, we show that future high-resolution tSZ-lensing
cross-correlation observations will serve as a powerful tool for
discriminating between different galactic feedback models.
U2 - 10.1088/1475-7516/2015/10/047
DO - 10.1088/1475-7516/2015/10/047
M3 - Article
SN - 1475-7516
VL - 10
SP - 47
JO - Journal of Cosmology and Astroparticle Physics (JCAP)
JF - Journal of Cosmology and Astroparticle Physics (JCAP)
IS - 10
ER -