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Dear all, </div>
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On Monday, March</span><span style="font-size: 14.67px; color: black;"> 31<sup>th</sup>, 2025 at
<b>9:00AM</b> </span><span style="font-size: 14.67px; color: rgb(0, 0, 0);">EDT</span><span style="font-size: 14.67px; color: black;">,
</span><span style="font-size: 11pt; color: black;">we will have a virtual seminar given by Archana Radhakrishnan of Tata Institute of Fundamental Research on the following Zoom link: </span></div>
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<span style="background-color: rgb(255, 255, 255);"><a href="https://jlab-org.zoomgov.com/j/1614062845?pwd=ZJ2oGOHp0vj9ipvRgYrKzY0epX8vpQ.1" target="_blank" id="LPlnkOWA69033389-f5e5-8149-2582-ea017de99cbe" class="OWAAutoLink" title="https://jlab-org.zoomgov.com/j/1614062845?pwd=ZJ2oGOHp0vj9ipvRgYrKzY0epX8vpQ.1" rel="noopener noreferrer" data-olk-copy-source="MessageBody" data-linkindex="0" data-auth="NotApplicable" style="margin: 0px; background-color: rgb(255, 255, 255); text-align: left;">https://jlab-org.zoomgov.com/j/1614062845?pwd=ZJ2oGOHp0vj9ipvRgYrKzY0epX8vpQ.1</a></span></div>
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<span style="background-color: rgb(255, 255, 255);">Although it’s not an in-person seminar, you can also join your colleagues for a remote streaming of the seminar in CEBAF Center F324-325.</span></div>
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Please see below for the title and abstract. </div>
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<b><u>Theory Seminar</u></b>:<b> </b>March 31<sup>th</sup>, <b>9pm</b> EDT (virtual) </div>
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<b><u>Speaker</u></b>: Archana Radhakrishnan (TIFR) </div>
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<span style="color: black;"><b><u>Title</u></b>:<b> </b></span><span style="color: rgb(32, 32, 32); background-color: rgb(255, 255, 255);">Exotic
<i>T<sub>bc</sub></i> Tetraquarks From Lattice QCD</span><span style="color: black;"> </span></div>
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<span style="font-family: Calibri, Helvetica, sans-serif; font-size: 11pt; color: black;"><b><u>Abstract</u></b>:
</span><span style="font-family: Calibri, Helvetica, sans-serif; font-size: 11pt; color: rgb(32, 32, 32); background-color: rgb(255, 255, 255); line-height: 1.284;">Research into doubly heavy tetraquarks has become highly relevant, especially with the recent
discovery of the doubly charmed tetraquark <i>T<sub>cc</sub></i>. In this talk, we present a lattice investigation of S-wave
<img data-file-id="6242679" width="34" height="15" style="width: 34px; height: 15px; max-width: 858px; margin: 0px;" src="https://mcusercontent.com/1de9c43e6d5e45ff0ecd664cd/images/68bd07e5-38e3-b8e2-a61d-73c26bc128e5.png"> scattering within the isoscalar axial-vector
and scalar channels. Both processes feature the flavor combination <img data-file-id="6242680" width="30" height="14" style="width: 30px; height: 14px; max-width: 858px; margin: 0px;" src="https://mcusercontent.com/1de9c43e6d5e45ff0ecd664cd/images/42a20a7a-4df7-f155-28b9-2b5bdbafab8f.png">,
which could potentially host tetraquarks. </span></p>
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</span></p>
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<span style="font-family: Calibri, Helvetica, sans-serif; font-size: 11pt; color: rgb(32, 32, 32); background-color: rgb(255, 255, 255); line-height: 1.284;">Our calculations were conducted on four different
<i>N<sub>f</sub></i> = 2+1 MILC gauge ensembles, each with varying lattice spacings and volumes. Utilizing the amplitude analysis method by Lüscher, we extracted the scattering amplitudes from the finite-volume spectra. We examine the light quark mass (<img data-file-id="6242681" width="30" height="14" style="width: 30px; height: 14px; max-width: 858px; margin: 0px;" src="https://mcusercontent.com/1de9c43e6d5e45ff0ecd664cd/images/62748273-defd-1612-f99f-98f8554d25bc.png">)
dependence of these amplitudes and extrapolate the amplitudes to the continuum. Our findings provide evidence for a bound state of the
<img data-file-id="6242680" width="30" height="14" style="width: 30px; height: 14px; max-width: 858px; margin: 0px;" src="https://mcusercontent.com/1de9c43e6d5e45ff0ecd664cd/images/42a20a7a-4df7-f155-28b9-2b5bdbafab8f.png"> tetraquark at the physical quark
mass (<img data-file-id="6242681" width="30" height="14" style="width: 30px; height: 14px; max-width: 858px; margin: 0px;" src="https://mcusercontent.com/1de9c43e6d5e45ff0ecd664cd/images/62748273-defd-1612-f99f-98f8554d25bc.png">) point within both the scalar
and the axial-vector channels.</span></p>
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See you on Monday. </div>
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Best regards, </div>
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<span style="background-color: white;">Joe, Zheng-Yang, Gloria and Adam</span></div>
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