Preface

Abstract

HEP 2021 - 38th Conference on Recent Developments in High Energy Physics and Cosmology was successfully held online between the 16th to the 19th of June 2021, in Thessaloniki, Greece. The conference was jointly organized and sponsored by the Hellenic Society for the Study of High Energy Physics, the Aristotle University of Thessaloniki and the Research Committee of the Aristotle University.In the context of the conference scholars and experts in the fields of Astroparticle and High Energy Physics, involved both in experimental and theoretical research, were invited from various universities and institutions. The conference focused on the most recent advancements in topics such as ‘Highlights from the LHC experimental results’, ‘Astroparticle Physics’, ‘Cosmology’, ‘String Theory’, ‘Dark Matter’ and others. The main goal was to present the related research work of the Greek scientific community, to promote the cooperation of experts and scholars in the field, to share the research achievements both on a national and international level. All accepted speakers were eligible to contribute to the Conference Proceedings on a voluntary basis.This collection of Proceedings compiles oral and paper presentations submitted by the authors and scrutinized by the Editorial Committee. Because of restrictions on travel and indoor activities related to COVID-19, we were forced to hold the conference online only. Attendees were notified well in advance that the on-site conference was changed to an online conference, where the timeline and order of the talks were defined. The online conference was held on the video conferencing software Zoom Meeting. The video-conference was held on the original set dates. Due to the large variety of topics and the relatively large number of attendees, the conference was separated into main and parallel sessions (Webinar Room and Parallel Session Rooms respectively). The complete conference program, the slides of the presentations and the recordings of all oral presentations are available online.The opening ceremony was held in the main Webinar Room, where the president of the Hellenic Society for the Study of High Energy Physics, Professor Katerina Zachariadou delivered the welcoming speech. Each plenary speaker gave an oral presentation of 35 minutes accompanied by her/his slides’ material, along with 5 minutes extra time, allocated for questions and discussion. A dedicated convener chaired each plenary session.The organizing and editorial committees of the HEP2021 hope you will enjoy the reading of this volume of the JPCS. Additionally, we want to thank all authors and participants for providing their valuable contributions for these proceedings, as well as the reviewers for their constructive recommendations and feedback aiding to improve the presented articles.List of Organizing and Program Committee, Editorial Board and Invited Speakers are available in this pdf.