Proof-of-principle <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msup><mml:mi>e</mml:mi><mml:mo>+</mml:mo></mml:msup></mml:math> source for future colliders

The PSI Positron Production (<a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:msup><a:mrow><a:mi mathvariant="normal">P</a:mi></a:mrow><a:mrow><a:mn>3</a:mn></a:mrow></a:msup></a:mrow></a:math> or P-cubed) experiment is a <d:math xmlns:d="http://www.w3.org/1998/Math/MathML" display="inline"><d:msup><d:mi>e</d:mi><d:mo>+</d:mo></d:msup></d:math> source and capture system with the potential to increase by an order of magnitude the state-of-the-art <f:math xmlns:f="http://www.w3.org/1998/Math/MathML" display="inline"><f:msup><f:mi>e</f:mi><f:mo>+</f:mo></f:msup></f:math> yield normalized to the drive linac energy, a highly desirable goal for future colliders. The experiment is framed in the FCC-ee injector study and will be hosted at SwissFEL, located at the Paul Scherrer Institute in Switzerland. This paper presents the <h:math xmlns:h="http://www.w3.org/1998/Math/MathML" display="inline"><h:mrow><h:msup><h:mrow><h:mi mathvariant="normal">P</h:mi></h:mrow><h:mrow><h:mn>3</h:mn></h:mrow></h:msup></h:mrow></h:math> project at an advanced stage, with an emphasis on a capture system featuring a novel <k:math xmlns:k="http://www.w3.org/1998/Math/MathML" display="inline"><k:msup><k:mi>e</k:mi><k:mo>+</k:mo></k:msup></k:math> matching device based on high-temperature superconducting solenoids, followed by two large aperture rf cavities surrounded by normal-conducting solenoids. The diagnostics design is also introduced, including monitors of charge, energy spectrum, and bunch-by-bunch longitudinal profile simultaneously for secondary <m:math xmlns:m="http://www.w3.org/1998/Math/MathML" display="inline"><m:msup><m:mi>e</m:mi><m:mo>+</m:mo></m:msup></m:math> and <o:math xmlns:o="http://www.w3.org/1998/Math/MathML" display="inline"><o:msup><o:mi>e</o:mi><o:mo>−</o:mo></o:msup></o:math>. The last chapter of the text overviews the currently ongoing installation at SwissFEL, including the beam transfer line, rf network, radiation protection, and other relevant activities toward the operation with <q:math xmlns:q="http://www.w3.org/1998/Math/MathML" display="inline"><q:msup><q:mi>e</q:mi><q:mo>+</q:mo></q:msup></q:math> in the coming years. Published by the American Physical Society 2024