Precision study of the eta3He system using the dp--> 3Heeta reaction.
The differential and total cross sections for the dp--> 3Heeta reaction have been measured in a high precision high statistics COSY-ANKE experiment near threshold using a continuous beam energy ramp up to an excess energy Q of 11.3 MeV with essentially 100% acceptance. The kinematics allowed the mean value of Q to be determined to about 9 keV. Evidence is found for the effects of higher partial waves for Q >or= 4 MeV. The very rapid rise of the total cross section to its maximum value within 0.5 MeV of threshold implies a very large eta3He scattering length and hence the presence of a quasibound state extremely close to threshold.
Mersmann
T
T
Institut für Kernphysik, Universität Münster, 48149 Münster, Germany.
Khoukaz
A
A
Büscher
M
M
Chiladze
D
D
Dymov
S
S
Hartmann
M
M
Hejny
V
V
Kacharava
A
A
Keshelashvili
I
I
Kulessa
P
P
Maeda
Y
Y
Mielke
M
M
Mikirtychiants
S
S
Ohm
H
H
Papenbrock
M
M
Prasuhn
D
D
Rathmann
F
F
Rausmann
T
T
Schleichert
R
R
Serdyuk
V
V
Stein
H-J
HJ
Ströher
H
H
Täschner
A
A
Valdau
Yu
Y
Wilkin
C
C
Wrońska
A
A