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<p>Dear all, </p>
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<p>our next EO meeting will take place this Thursday <b>Feb 21</b> at <b>13:00</b> in the KTH meeting room on the 5th floor. </p>
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<p><span style="font-size: 12pt;"><b>Filip Samuelsson</b> will present the following talk</span><br>
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Title: The problematic connection between gamma-ray bursts (GRBs) and ultra-high energy cosmic rays (UHECR)</div>
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Abstract: The acceleration site for UHECR is still an open question despite extended research. We consider the prompt phase of GRBs as a possible origin for these high energy particles. Under the likely assumption that electrons are also accelerated at the
UHECR acceleration site, synchrotron emission from these co-accelerated electrons is inevitable. We characterize this synchrotron emission and compare it to observed GRB spectra and find that for standard parameters, the synchrotron flux from these electrons
would be much too luminous. This result challenges both high- and low-luminosity GRBs as accelerators of UHECR.</div>
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<p style="font-size:16px; font-family:Calibri,Helvetica,sans-serif">---------------------------------</p>
<p style="font-size:16px; font-family:Calibri,Helvetica,sans-serif">André da Silva Schneider<br>
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<p style="font-size:16px; font-family:Calibri,Helvetica,sans-serif"><span style="font-size:10pt; font-family:Calibri,Helvetica,sans-serif,serif,EmojiFont">Department of Astronomy</span><br>
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<p style="font-size:16px; font-family:Calibri,Helvetica,sans-serif"><span style="font-family:Calibri,Helvetica,sans-serif,serif,EmojiFont"><span style="font-size:10pt">Stockholm University</span></span></p>
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