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Past, Present and Future of the n_TOF Facility at CERN
E. Chiaveri,S. Andriamonje,M. Calviani,V. Vlachoudis,M. Brugger,P. Cennini,F. Cerutti,M. Chin,A. Ferrari,Y. Kadi,E. Lebbos,R. Losito,C. Guerrero,V. Becares,D. Cano-Ott,M. Fernandez-Ordonez,E. Gonzalez 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.23
The n_TOF spallation neutron facility is operating at CERN since 2001. Neutrons are produced with a very wide energy range, from thermal up to 1 GeV and with a very high instantaneous flux (10^5n/cm^2/pulse at 200 m from target) thanks to the high intensity (7 × 10^(12) protons/pulse) and low repetition rate of the Proton Synchrotron (PS) which is delivering protons to a lead spallation target. The experimental area is located at 200 m from the target, resulting in a very good energy resolution and beam quality thanks to the adoption of an optimal collimation system. At the end of 2008 the n_TOF facility has resumed operation after a halt of 3 years due to technical issues. This contribution will outline the main physics results obtained by the facility since its inception in 1999, and show the importance of the measured nuclear data in the field of Nuclear Astrophysics and Nuclear Technology. Then it will present the future perspectives of the facility, aiming mainly in the direction of measuring highly radioactive samples, for which the facility has unique capabilities, with a lower background.
Characterization of the New n_TOF Neutron Beam: Fluence, Profile and Resolution
C. Guerrero,V. Becares,D. Cano-Ott,M. Fernandez-Ordonez,E. Gonzalez-Romero,F. Martin-Fuertes,T. Martinez,E. Mendoza,G. Pina,J. Quinones,V. Vlachoudis,M. Calviani,S. Andriamonje,M. Brugger,F. Cerutti,E 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.23
After a halt of four years, the n_TOF spallation neutron facility at CERN has resumed operation in November 2008 with a new spallation target characterized by an improved safety and engineering design, resulting in a more robust overall performance and efficient cooling. The first measurement during the 2009 run has aimed at the full characterization of the neutron beam. Several detectors, such as calibrated fission chambers, the n\textunderscore TOF Silicon Monitor, a MicroMegas detector with ^(10)B and ^(235)U samples, as well as liquid and solid scintillators have been used in order to characterize the properties of the neutron fluence. The spatial profile of the beam has been studied with a specially designed "X-Y" MicroMegas which provided a 2D image of the beam as a function of neutron energy. Both properties have been compared with simulations performed with the FLUKA code. The characterization of the resolution function is based on results from simulations which have been verified by the study of narrow capture resonances of ^(56)Fe, which were measured as part of a new campaign of (n, γ) measurements on Fe and Ni isotopes.
The Role of Fe and Ni for S-Process Nucleosynthesis and Innovative Nuclear Technologies
G. Giubrone,J. L. Tain,C. Lederer,A. Pavlik,A. Wallner,S. Andriamonje,M. Brugger,M. Calviani,F. Cerutti,E. Chiaveri,A. Ferrari,Y. Kadi,E. Lebbos,V. Vlachoudis,J. Andrzejewski,J. Marganiec,J. Perkowski 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.23
The accurate measurement of neutron capture cross sections of all Fe and Ni isotopes is important for disentangling the contribution of the s-process and the r-process to the stellar nucleosynthesis of elements in the mass range 60 < A < 120. At the same time, Fe and Ni are important components of structural materials and improved neutron cross section data is relevant in the design of new nuclear systems. With the aim of obtaining improved capture data on all stable iron and nickel isotopes, a program of measurements has been launched at the CERN Neutron Time of Flight Facility n_TOF.