Аннотация
Pressure profiles are sensitive probes of the thermodynamic conditions and
the internal structure of galaxy clusters. The intra-cluster gas resides in
hydrostatic equilibrium within the Dark Matter gravitational potential.
However, this equilibrium may be perturbed, e.g. as a consequence of thermal
energy losses, feedback and non-thermal pressure supports. Accurate measures of
the gas pressure over the cosmic times are crucial to constrain the cluster
evolution as well as the contribution of astrophysical processes. In this work
we presented a novel algorithm to derive the pressure profiles of galaxy
clusters from the Sunyaev-Zeldovich (SZ) signal measured on a combination of
Planck and South Pole Telescope (SPT) observations. The synergy of the two
instruments made it possible to track the profiles on a wide range of spatial
scales. We exploited the sensitivity to the larger scales of the Planck
High-Frequency Instrument to observe the faint peripheries, and the higher
spatial resolution of SPT to solve the innermost regions. We developed a
two-step pipeline to take advantage of the specifications of each instrument.
We first performed a component separation on the two data-sets separately to
remove the background (CMB) and foreground (galactic emission) contaminants.
Then we jointly fitted a parametric pressure profile model on a combination of
Planck and SPT data. We validated our technique on a sample of 6 CHEX-MATE
clusters detected by SPT. We compare the results of the SZ analysis with
profiles derived from X-ray observations with XMM-Newton. We find an excellent
agreement between these two independent probes of the gas pressure structure.
Пользователи данного ресурса
Пожалуйста,
войдите в систему, чтобы принять участие в дискуссии (добавить собственные рецензию, или комментарий)