[colloquium] Crowd-sourcing galaxy clusters confirmation with non-professional telescopes

by Christophe Ringeval (CP3)

Thursday 15 Nov 2018, 14:00 → 15:00 Europe/Brussels

CYLC01 (Marc de Hemptinne (chemin du Cyclotron, 2, Louvain-la-Neuve))

The new all sky and multi-wavelength astrophysical and cosmological surveys are, and will be, providing an unprecedented amount of information on a plethora of cosmic objects. Many of them are foregrounds for the original science goals and cannot received the same attention as the mission main objectives.
 
Within the Planck satellite maps of our universe, a space telescope dedicated to the observation of the Cosmic Microwave Background, a few thousand of so far undetected galaxy clusters are letting very peculiar imprints through the so-called Sunyaev Zel'dovich effect. These cluster candidates have never been observed with optical telescopes and confirmation of their true nature requires a significant amount of professional telescope time.

In this talk, I will present a proof-of-concept of crowd-sourcing galaxy clusters optical confirmation with amateur astronomers. Using a non-professional telescope of 62cm provided by the Astroqueyras association in Saint-Véran (France), we have been able to confirm one of the Planck cluster candidate and to extract various of its properties, such as distance, redshift and mass.

Although the exposure time required to image one cluster candidate is an order of magnitude larger than with a professional telescope, there are orders of magnitude more amateur astronomers than professionals thereby rendering the concept useful to many other surveys. They are the South Pole Telescope, the Atacama Cosmology Telescope, future X-ray spatial missions such as eRosita, and all of the searches for gravitational wave optical counterparts.

irmp_colloquium_18.pdf