We propose a new measurement of the ratio of positronproton to electronproton elastic scattering at DESY. The purpose is to determine the contributions beyond singlephoton exchange, which are essential for the Quantum Electrodynamic (QED) description of the most fundamental process in hadronic physics. By utilizing a 20 cm long liquid hydrogen target in conjunction with the extracted beam from the DESY synchrotron, we can achieve an average luminosity of
The fluoropolymer CYTOP was investigated in order to evaluate its suitability as a coating material for ultracold neutron (UCN) storage vessels. Using neutron reflectometry on CYTOPcoated silicon wafers, its neutron optical potential was measured to be 115.2(2) neV. UCN storage measurements were carried out in a 3.8 l CYTOPcoated aluminum bottle, in which the storage time constant was found to increase from 311(9) s at room temperature to 564(7) s slightly above 10 K. By combining experimental storage data with simulations of the UCN source, the neutron loss factor of CYTOP is estimated to decrease from 1.1(1)
 Award ID(s):
 2111046
 NSFPAR ID:
 10369957
 Publisher / Repository:
 Springer Science + Business Media
 Date Published:
 Journal Name:
 The European Physical Journal A
 Volume:
 58
 Issue:
 7
 ISSN:
 1434601X
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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