At the Frontier of Multi-Messenger Astrophysics

Dear Colleagues,

Except photons which are the first messengers that hold the holy grail of observational astronomy and astrophysics, three other important physical phenomena/messengers (i.e. weakly and strongly interacting particles—such as neutrinos and nuclei—and oscillations of the fabric of space–time manifesting as gravitational waves) come together to offer a new synergistic and extraordinary tool of studying and understanding the high-energy universe.

The so-called multimessenger astrophysics makes use of four astrophysical types of messengers: electromagnetic radiation (i.e., radio waves, infrared, to visible light, ultraviolet emission, to X-rays and rays), cosmic rays, neutrinos, and gravitational waves. All these four originate from distant and mysterious astrophysical sources, each of them telling us a different exciting story about obscure galactic and extragalactic worlds, like the active galactic nuclei (black holes) and their relativistic plasma jets, neutron-stars, supernovae and gamma-ray bursts.

Multi-messenger astrophysics is a relatively new field in astrophysics. It started around 30 years ago when we were able to observe, for the first time, messengers (i.e., neutrinos) other than photons coming from the famous SN1987A. Today, various modern observatories, air-borne probes, and telescopes around the globe monitor the whole sky and collectively operate to complement each other as they continuously analyze tons of observational data (cosmic rays, neutrinos, gamma-rays, gravitational ways).

We invite you to share your expertise in this Special Issue dedicated to the exciting field of multi-messenger astrophysics, and we welcome you to contribute original articles or reviews about observational data analyses, perspectives and interpretations, theoretical models, or descriptions about new technological visions concerning designs of new experimental and observational facilities, all of which could help to bring our interpretation of a high-energy universe into a whole new level of understanding.

Dr. Athina Meli
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Galaxies is an international peer-reviewed open access quarterly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The publishing fee of the paper submitted in the first half of 2021 will be waived. Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

• particles
• cosmic rays
• cosmic neutrinos
• gamma-rays
• gravitational waves
• multi-messengers
• neutrino telescopes
• cosmic-ray observatories