GCOS - The Global Cosmic Ray Observatory

GCOS - The Global Cosmic Ray Observatory

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The Global Cosmic Ray Observatory - GCOS is an intended next-generation observatory to measure the properties of the highest-energy particles in the Universe with unprecedented precision after the year 2030.

At present, the largest detector for cosmic rays is the Pierre Auger observatory in Malargüe, Argentina, covering an area of 3000 km2. To increase its sensitivity to the type of particle, at present, additional components are being installed at the observatory. In the northern hemisphere the Telescope Array , located in Utah, USA, is covering an area of 700 km2, presently undergoing an extension to cover about 2800 km2. Objective of these installations is to measure the properties of ultra high-energy cosmic rays with unprecedented precision in the next decade (until about 2030). Key properties include the arrival direction (on the sky), the energy, and the particle type.

The flux of particles provided by Nature at the highest energies is small and to address the physics questions, a new facility is needed after 2030 with an acceptance at least an order of magnitude larger than the existing observatories.

Brainstorming Workshop May 17th-24th, 2021

To get the project initiated we aim to organize a brainstorming meeting/workshop. The workshop will be an online meeting held by zoom. Objective of the workshop will be to collect ideas about the physics case of GCOS and to brainstorm potential designs and detector concepts of the future observatory.

Organizers: Rafael Alves Batista, Antonella Castellina, Raloh Engel, Toshihiro Fujii, Jörg R. Hörandel (chair), Charles Jui, Lu Lu, Ioana Maris, Shoichi Ogio, Takashi Sako, Fred Sarazin.

More information on the workshop is available on the Workshop INDICO page.

The results of the brainstorming meeting should be written up in a white paper for GCOS. This white paper will be important to feed GCOS into the ongoing Snowmass process but also to feed the GCOS concept to other national and international (APPEC, ESFRI, ...) roadmap processes.

If you are interested in the GCOS project and you want to contribute to it or follow our progress, please sign up to our email list.

For more information, please contact Jörg R. Hörandel