J.H. Koivuniemi
Helsinki University of Technology
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Publication
Featured researches published by J.H. Koivuniemi.
POLARIZED ION SOURCES, TARGETS AND POLARIMETRY ‐ PSTP2007: 12th International Workshop | 2008
N. Doshita; J. Ball; Günter Baum; F. Gautheron; S. Goertz; T. Hasegawa; J. Heckmann; Ch Hess; N. Horikawa; S. Ishimoto; T. Iwata; Yu. Kisselev; J.H. Koivuniemi; K. Kondo; A. Magnon; C. Marchand; T. Matsuda; W. Meyer; T. Michigami; E. Radtke; G. Reicherz
The COMPASS experiment has been taking data since 2002. Its polarized target was upgraded during the 2005 CERN SPS shutdown. With the high acceptance magnet we obtained +56.0% and −53.0% deuteron polarization in 6LiD. In 2007 ammonia is used as a proton target which has a relaxation time of ∼4000u2009h at 0.6 T.
Czechoslovak Journal of Physics | 2005
N. Doshita; J. Ball; Günter Baum; M. Finger; F. Gautheron; S. Goertz; T. Hasegawa; N Horikawa; S. Ishimoto; Tadahisa Iwata; Yu. Kisselev; J.H. Koivuniemi; K. Kondo; T. Matsuda; W. Meyer; S. Neliba; G. Reicherz
The spin structure of the nucleons is investigated by studying spin dependent process of deep inelastic scattering of a polarized muon beam and a polarized nucleon target in the COMPASS experiment since 2001. In order to achieve high luminosities it is necessary to use a large solid polarized target. The target consists of two independent and oppositely longitudinal polarized cells. The cells are filled with irradiated6LiD granulated material. One of the characteristics of the polarized target is the spin reversal by magnetic field rotation in order to cancel the systematic error. The polarized target apparatus consists of a large refrigerator providing a low temperature of below 100 mK and a high cooling power with 200–300 mK, a superconducting magnet producing 2.5 T with good field homogeneity, two high power of a few watts microwave systems producing 70 GHz for Dynamic Nuclear Polarization (DNP) and 10 NMR signals detection system for the polarization measurement.
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment | 2004
K. Kondo; J. Ball; Günter Baum; P. Berglund; N. Doshita; F. Gautheron; S. Goertz; T. Hasegawa; N Horikawa; S. Ishimoto; Tadahisa Iwata; Yu. Kisselev; J.H. Koivuniemi; Jm LeGoff; A. Magnon; T. Matsuda; W. Meyer; G. Reicherz
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment | 2004
N. Doshita; J. Ball; Günter Baum; P. Berglund; F. Gautheron; S. Goertz; K Gustafsson; T. Hasegawa; N Horikawa; S. Ishimoto; Tadahisa Iwata; Yu. Kisselev; J.H. Koivuniemi; K. Kondo; T. Matsuda; W. Meyer; G. Reicherz; N. Takabayashi
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment | 2004
F. Gautheron; J. Ball; Günter Baum; P. Berglund; N. Doshita; S. Goertz; K Gustafsson; N Horikawa; Yu. Kisselev; J.H. Koivuniemi; K. Kondo; W. Meyer; G. Reicherz
Proceedings of the 16th International Spin Physics Symposium and Workshop on Polarized Electron Sources and Polarimeters | 2005
F. Gautheron; Günter Baum; Yu. Kisselev; N. Doshita; S. Goertz; J.H. Koivuniemi; K. Kondo; W. Meyer; G. Reicherz; J. Ball; A. Magnon; C. Marchand
