Autoren:	Backe, Hartmut Lauth, Werner Drexler, Peter Heil, Philipp Klag, Pascal Ledroit, Ben Stieler, Frederic
Titel:	Design study for a 500 MeV positron beam at the Mainz Microtron MAMI
Online-Publikationsdatum:	19-Dez-2022
Erscheinungsdatum:	2022
Sprache des Dokuments:	Englisch
Zusammenfassung/Abstract:	A design study has been performed for a positron beam with an energy of 500 MeV to be realized at the applied physics area of the Mainz Microtron MAMI. Positrons will be created after pair conversion of bremsstrahlung, produced by the 855 MeV electron beam at MAMI in a tungsten converter target. From the two conceivable geometries (1) pair conversion in the bremsstrahlung converter target itself, and (2) bremsstrahlung pair conversion in a separated lead foil, the former was considered in detail. Positrons will be energy selected within an outside open electron beam-line bending magnet, and bent back by an additional sector magnet. Magnetic focusing elements in between are designed to prepare in a well shielded positron target chamber about 6 m away from the target a beam with horizontal and vertical emittances of ϵv = 0.055 π mm mrad (1 σ), and ϵh=0.12π mm mrad (1 σ), respectively, for a 10 μm thick amorphous tungsten target and negligible momentum spread. At an accepted positron band width of 1 MeV, spots are expected vertically with an angular spread of 0.064 mrad and a size of 5.0 mm (FWHM), and horizontally with an angular spread of 0.64 mrad and a size of 7.7 mm (FWHM). The positron yield amounts to 13.1 per second, 1 MeV positron energy band width, and 1 nA electron beam current.
DDC-Sachgruppe:	530 Physik 530 Physics
Veröffentlichende Institution:	Johannes Gutenberg-Universität Mainz
Organisationseinheit:	FB 08 Physik, Mathematik u. Informatik
Veröffentlichungsort:	Mainz
ROR:	https://ror.org/023b0x485
DOI:	http://doi.org/10.25358/openscience-8361
Version:	Published version
Publikationstyp:	Zeitschriftenaufsatz
Nutzungsrechte:	CC BY
Informationen zu den Nutzungsrechten:	https://creativecommons.org/licenses/by/4.0/
Zeitschrift:	The European physical journal : D 76
Seitenzahl oder Artikelnummer:	150
Verlag:	Springer
Verlagsort:	Berlin u.a.
Erscheinungsdatum:	2022
ISSN:	1434-6079
DOI der Originalveröffentlichung:	10.1140/epjd/s10053-022-00465-9
Enthalten in den Sammlungen:	DFG-491381577-H