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Dear All,<br />
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PYTHIA 8.306 has been released today, and can be downloaded from</div>
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<li>http://pythia.org</li>
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<div dir="auto">Note that this is the first release to the new Pythia.org webpage. <br />
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This is an "unscheduled" bug fix update, prompted by a showstopper bug in Powheg matching code, but a few other minor fixes are included also. A brief summary is included below and in the Update History part of the HTML manual.<br />
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Wishing you an enjoyable experience with PYTHIA 8.306.<br />
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Sincerely yours,<br />
The Pythia 8 Collaboration<br />
(Christian Bierlich, Nishita Desai, Leif Gellersen, Ilkka Helenius, Philip Ilten, Leif Lönnblad, Stephen Mrenna, Stefan Prestel, Christian Preuss, Torbjörn Sjöstrand, Peter Skands, Marius Utheim, Rob Verheyen)<br />
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CONTACT: if you need to contact any of the authors, please use the new authors@pythia.org address, as it allows us to coordinate replies. You may also include the individual addresses of authors that are relevant for a specific issue. Never contact several persons independently on the same topic, thereby potentially leading to double work. Abuse will have consequences.<br />
<br />
When responding to emails from us at authors@pythia.org, reply directly to the email, which has a unique return address of the form incoming+<hash>@incoming.gitlab.com, and _not_ authors@pythia.org. Please consider allowing your correspondence to be made publicly available to other users via our issue tracker, by replying at any point with your express permission, e.g. "this correspondence can be made public".<br />
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<span style="color:var(--textColor);background-color:var(--backgroundColor)">Summary list of changes for 8.306.</span></div>
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<li>Fixed incorrect scale being set when applying the POWHEG veto (e.g., main31.cc). Note that the number of emissions is correct in 8.303, but is incorrect in 8.304 and 8.305. Thanks to Mikhail Kirsanov.</li>
<li>Fixed repeated initialization causing an ever expanding physics pointer list in the main Pythia class.</li>
<li>Fixed issue for HepMC output from Vincia, which would previously issue warnings about inconsistent mother/daughter relationships, caused by Vincia's antenna-style bookkeeping by which emitted partons have two mothers instead of one. Minor modifications to Vincia's QCD shower to ensure that the first mother is the one that changed colour and hence would be identified with the "radiator" in a collinear context. Analogous modifications for QED so the most collinear parent is the first mother. </li>
<li>Removed assert statements from Angantyr.</li>
<li>Shortened Pythia constructor header.</li>
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