In this, second edition of the MACROS workshop, we plan to have about 40 participants, interested in the many unsolved mysteries surrounding cosmic rays. The previous workshop MACROS 2013 which focused on UHECRs and associated multi-messenger signals was very successful, and led to fruitful collaborations. Since then, many exciting results (e.g., updates of IceCube neutrino data, Telescope Array hotspot) have come out. It is now timely to have intensive discussions to move forward.

Among other things, in MACROS 2016 we will be discussing the following points:

1. Current challenges and problems in transient sources and associated cosmic-ray accelerators

2. Do we already have clues to the origins of cosmic rays around the knee and second knee?

3. Building an international network on high energy cosmic-ray research, to discuss future multi-messenger experiments (IceCube-Gen2, KM3Net, GRAND, CTA, ISS-CREAM, TA4, etc.)

Because the young scientists in this field today will certainly be the key actors of the next twenty years, our aim is to organise a workshop that is dedicated to discussions among active researchers in the field, especially led by emerging junior researchers.

The organising committee:
Kumiko Kotera
Jean-Phillipe Lenain
Kohta Murase (LOC chair)
Foteini Oikonomou
John Pretz
Ian Shoemaker

The MACROS workshop is supported by the Penn State Institute of Gravitation and the Cosmos.