[Zurück]

F. Gunsing, G. Badurek, E. Jericha, H. Leeb, H. Oberhummer, -. nTOF Collaboration:
"Status and outlook of the neutron time-of-flight facility n_TOF at CERN";
Nuclear Instruments & Methods in Physics Research Section B, 261 (2007), S. 925 - 929.

The neutron time-of-flight facility n_TOF at CERN, fully operational since 2002, combines a high instantaneous neutron flux with
high energy resolution. The wide energy range and the high neutron flux per time-of-flight burst result in a much enhanced signal to
background ratio for neutron capture of radioactive isotopes and makes this facility well suited for the measurement of high quality
neutron-induced reaction cross-sections.
Neutrons are created by spallation reactions induced by a pulsed 20 GeV/c proton beam impinging on a lead target. A 5 cm water slab
surrounding the lead target serves as a coolant and at the same time as a moderator of the spallation neutron spectrum, providing a wide
energy spectrum from 0.1 eV to about 250 MeV.
By the end of 2005, a first phase of data taking has been successfully terminated. Fission and capture experiments have been performed
on a variety of isotopes of interest for nuclear astrophysics, advanced nuclear technologies and for basic nuclear physics.
The instrumentation developed for this facility consists of parallel plate avalanche counter and fission ionization chamber detectors
for the fission experiments and of low mass C6D6 detectors and a 4 pi BaF2 total absorption calorimeter for capture experiments. A new
data acquisition system, based on sampling of the detector signals, has been developed to cope with the high count rates and to minimize
the effective dead time to only a few tens of nanosecond.
A second phase of data taking is planned to start in 2007, after an upgrade of the spallation target. On the longer term, the construction
of a flight path at 20 m resulting in an increased neutron flux of about a factor of 100 opens new possibilities.