Determination of the η(')-proton scattering length in free space.

Authors :: Czerwiński E
Moskal P
Silarski M
Bass SD
Grzonka D
Kamys B
Khoukaz A
Klaja J
Krzemień W
Oelert W
Ritman J
Sefzick T
Smyrski J
Täschner A
Wolke M
Zieliński M
Source :: Physical review letters [Phys Rev Lett] 2014 Aug 08; Vol. 113 (6), pp. 062004. Date of Electronic Publication: 2014 Aug 08.
Publication Year :: 2014
Abstract: Taking advantage of both the high mass resolution of the COSY-11 detector and the high energy resolution of the low-emittance proton beam of the cooler synchrotron COSY, we determine the excitation function for the pp→ppη(') reaction close to threshold. Combining these data with previous results, we extract the scattering length for the η(')-proton potential in free space to be Re(a(pη(')))=0±0.43 fm and Im(a(pη(')))=0.37(-0.16)(+0.40) fm.