<html xmlns="http://www.w3.org/1999/xhtml"> <head> <title></title> </head> <body> <div name="messageBodySection"> <div dir="auto">Dear friends of Pythia, We are very glad to announce the completion of <a style="font-family:-apple-system, BlinkMacSystemFont, Segoe UI, Roboto, Helvetica Neue, Arial, Noto Sans, sans-serif, Apple Color Emoji, Segoe UI Emoji, Segoe UI Symbol, Noto Color Emoji;font-size: 1.1rem" href="https:///literature/2056998" target="_blank">A comprehensive guide to the physics and usage of PYTHIA 8.3</a><span style="color:rgba(0, 0, 0, 0.8);font-family:-apple-system, BlinkMacSystemFont, Segoe UI, Roboto, Helvetica Neue, Arial, Noto Sans, sans-serif, Apple Color Emoji, Segoe UI Emoji, Segoe UI Symbol, Noto Color Emoji"> which was put on arXiv last week (e-Print: <a style="font-family:-apple-system, BlinkMacSystemFont, Segoe UI, Roboto, Helvetica Neue, Arial, Noto Sans, sans-serif, Apple Color Emoji, Segoe UI Emoji, Segoe UI Symbol, Noto Color Emoji" href="https:////arxiv.org/abs/2203.11601" target="_blank">2203.11601</a><span style="color:#0050b3;font-family:-apple-system, BlinkMacSystemFont, Segoe UI, Roboto, Helvetica Neue, Arial, Noto Sans, sans-serif, Apple Color Emoji, Segoe UI Emoji, Segoe UI Symbol, Noto Color Emoji">). This guide offers the first self-contained dedicated coverage of all aspects of Pythia 8 in depth. Spanning 315 pages, the contents are split into three parts: Introduction, Physics, and Usage, and there is a helpful detailed table of contents at the front and an index and acronym list at the back. Previous descriptions of Pythia 8 were limited to summaries and introductions, and still often referred to the old Pythia 6.4 manual for details. However, with the physics and capabilities of Pythia 8 increasingly surpassing those of Pythia 6, the correspondence with the 6.4 manual was becoming less reliable, and in any case the algorithmic context there was the very differently structured Pythia 6 library. The new comprehensive guide to Pythia 8.3 has been rewritten from the ground up to stand on its own without referring to the 6.4 manual except casually where appropriate. This guide is therefore intended to fully replace the 6.4 manual as the main review-style reference for the physics and usage of Pythia 8. As usual, even a document this size cannot hope to capture all derivations and physical arguments in detail. Pythia relies on a large body of original work - contributed to by authors, students, external contributors, and the community at large, including experimental studies - which we have made an effort to point to throughout the guide with references that you can turn to for further details. When using the program to produce your own results, we ask that you also make an effort to respect these works - and their authors - by citing not just the Pythia manual but also those original works that could be deemed to have direct bearing on your study. This was a collaborative project which involved all of the members of the Pythia Collaboration. But especially Christian Bierlich deserves thanks for coordinating and pulling the effort together as editor-in-chief during the approximately two years it took to complete. Sincerely, The Pythia Collaboration <a href="https://pythia.org" target="_blank">https://pythia.org</a></div> </div> </body> </html>