Photoproduction of doubly charmed tetraquark Tcc via photon-gluon fusion at ILC and CLIC

The photoproduction of doubly charmed tetraquark <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:msub><a:mi>T</a:mi><a:mrow><a:mi>c</a:mi><a:mi>c</a:mi></a:mrow></a:msub></a:math> is predicted through the resolved channel <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:mi>γ</c:mi><c:mo>+</c:mo><c:mi>g</c:mi><c:mo stretchy="false">→</c:mo><c:mo stretchy="false">⟨</c:mo><c:mi>c</c:mi><c:mi>c</c:mi><c:mo stretchy="false">⟩</c:mo><c:mo stretchy="false">[</c:mo><c:mi>n</c:mi><c:mo stretchy="false">]</c:mo><c:mo>+</c:mo><c:mover accent="true"><c:mi>c</c:mi><c:mo stretchy="false">¯</c:mo></c:mover><c:mo>+</c:mo><c:mover accent="true"><c:mi>c</c:mi><c:mo stretchy="false">¯</c:mo></c:mover><c:mo stretchy="false">→</c:mo><c:msub><c:mi>T</c:mi><c:mrow><c:mi>c</c:mi><c:mi>c</c:mi></c:mrow></c:msub><c:mo>+</c:mo><c:mover accent="true"><c:mi>c</c:mi><c:mo stretchy="false">¯</c:mo></c:mover><c:mo>+</c:mo><c:mover accent="true"><c:mi>c</c:mi><c:mo stretchy="false">¯</c:mo></c:mover></c:math> at ILC and CLIC. At <s:math xmlns:s="http://www.w3.org/1998/Math/MathML" display="inline"><s:msup><s:mi>e</s:mi><s:mo>+</s:mo></s:msup><s:msup><s:mi>e</s:mi><s:mo>−</s:mo></s:msup></s:math> colliders, the initial photons <u:math xmlns:u="http://www.w3.org/1998/Math/MathML" display="inline"><u:mi>γ</u:mi></u:math> can be produced from two primary sources, well-delineated within the Weizäcker Williams approximation (WWA) and the laser backscattering (LBS). And the initial gluon can be emitted from the photon. The spin and color quantum number [<w:math xmlns:w="http://www.w3.org/1998/Math/MathML" display="inline"><w:mi>n</w:mi></w:math>] of the intermediate diquark configuration can be <y:math xmlns:y="http://www.w3.org/1998/Math/MathML" display="inline"><y:mrow><y:mo stretchy="false">⟨</y:mo><y:mi>c</y:mi><y:mi>c</y:mi><y:mo stretchy="false">⟩</y:mo><y:mo stretchy="false">[</y:mo><y:msub><y:mrow><y:mmultiscripts><y:mrow><y:mi>S</y:mi></y:mrow><y:mprescripts/><y:none/><y:mrow><y:mn>3</y:mn></y:mrow></y:mmultiscripts></y:mrow><y:mrow><y:mn>1</y:mn></y:mrow></y:msub><y:msub><y:mrow><y:mo stretchy="false">]</y:mo></y:mrow><y:mrow><y:mover accent="true"><y:mrow><y:mn>3</y:mn></y:mrow><y:mrow><y:mo stretchy="false">¯</y:mo></y:mrow></y:mover></y:mrow></y:msub></y:mrow></y:math>. Then its nonperturbative hadronization to <gb:math xmlns:gb="http://www.w3.org/1998/Math/MathML" display="inline"><gb:msub><gb:mi>T</gb:mi><gb:mrow><gb:mi>c</gb:mi><gb:mi>c</gb:mi></gb:mrow></gb:msub></gb:math> was discussed in the phenomenological potential models. Finally, the differential distributions and theoretical uncertainty of the doubly charmed tetraquark <ib:math xmlns:ib="http://www.w3.org/1998/Math/MathML" display="inline"><ib:msub><ib:mi>T</ib:mi><ib:mrow><ib:mi>c</ib:mi><ib:mi>c</ib:mi></ib:mrow></ib:msub></ib:math> were analyzed. As the collision energy increases, the contribution of the resolved photon channel will become increasingly significant, and it may even dominate the production of <kb:math xmlns:kb="http://www.w3.org/1998/Math/MathML" display="inline"><kb:msub><kb:mi>T</kb:mi><kb:mrow><kb:mi>c</kb:mi><kb:mi>c</kb:mi></kb:mrow></kb:msub></kb:math> with the laser backscattering spectrum. The conclusion is that it is promising to observe <mb:math xmlns:mb="http://www.w3.org/1998/Math/MathML" display="inline"><mb:msub><mb:mi>T</mb:mi><mb:mrow><mb:mi>c</mb:mi><mb:mi>c</mb:mi></mb:mrow></mb:msub></mb:math> via the resolved channel of photoproduction both at the ILC and CLIC, and the results have a strong dependence on the mass of constituent charm quark <ob:math xmlns:ob="http://www.w3.org/1998/Math/MathML" display="inline"><ob:msub><ob:mi>m</ob:mi><ob:mi>c</ob:mi></ob:msub></ob:math> and the potential model.