XYZ spectroscopy at electron-hadron facilities. III. Semi-inclusive processes with vector exchange

Inclusive production processes will be important for the first observations of <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mi>X</a:mi><a:mi>Y</a:mi><a:mi>Z</a:mi></a:math> states at new generation electron-hadron colliders, as they generally benefit from larger cross sections than their exclusive counterparts. We make predictions of semi-inclusive photoproduction of the <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:msub><c:mi>χ</c:mi><c:mrow><c:mi>c</c:mi><c:mn>1</c:mn></c:mrow></c:msub><c:mo stretchy="false">(</c:mo><c:mn>1</c:mn><c:mi>P</c:mi><c:mo stretchy="false">)</c:mo></c:math> and <g:math xmlns:g="http://www.w3.org/1998/Math/MathML" display="inline"><g:mi>X</g:mi><g:mo stretchy="false">(</g:mo><g:mn>3872</g:mn><g:mo stretchy="false">)</g:mo></g:math>, whose peripheral production is assumed to be dominated by vector exchanges. We validate the applicability of vector meson dominance in the axial-vector charmonium sector and calculate production rates at center-of-mass energies relevant for future experimental facilities. We find the semi-inclusive cross sections near the threshold to be enhanced by a factor of <k:math xmlns:k="http://www.w3.org/1998/Math/MathML" display="inline"><k:mo>∼</k:mo><k:mn>2</k:mn><k:mi>–</k:mi><k:mn>3</k:mn></k:math> compared to the exclusive reaction and well-suited for a first observation in photoproduction. Published by the American Physical Society 2024