TY - JOUR
T1 - Design, manufacturing and performance of a pair of superconducting solenoids for a neutron spin-echo spectrometer at the SNS
AU - Walter, Wolfgang
AU - Boffo, Cristian
AU - Borlein, Markus
AU - Kozielewski, Tadeusz
AU - Monkenbusch, Michael
AU - Ohl, Michael
AU - Paul, Amitesh
AU - Schrauth, Bernhard
AU - Sikler, Guenther
AU - Tiemann, Christoph
PY - 2009/6
Y1 - 2009/6
N2 - A Neutron spin-echo (NSE) spectrometer of the next generation is under construction at the Spallation Neutron Source (SNS) in Oak Ridge, USA. A NSE spectrometer measures small velocity changes of the neutrons encoded by the neutrons spin clock at a sample while the Neutron spin precesses in large magnetic fields following Bloch's equation. This instrument will be the best of its class both with respect to resolution and dynamic range. In order to reach this ambitious goal, a large magnetic precision field integral before and after the sample is required which directly scales linearly with the resolution of the instrument. Therefore superconducting technology will be used to allow for a higher magnetic field integral. Here, we present the design, manufacturing and test performance of the solenoids which are the result of a collaboration between Jiilich Research Center (FZJ) and Babcock Noell GmbH (BNG). The solenoids generate an integrated magnetic flux density of 1.8 T*m and use active shielding to reduce the fringe field. The operation temperature of about 4 K is reached by means of pulse-tube coolers in order to minimize vibrations. A special feature of this magnet system is the very accurate measurement of the cold mass-position after cool-down and during operation. The accuracy of this measurement system is in the order of micrometers. This information is required for the adjustment of so called Fresnel coils outside the cryostat. Using these correction elements, a field integral homogeneity better than 10-6 T m for different Neutron paths through one of the solenoids can be achieved.
AB - A Neutron spin-echo (NSE) spectrometer of the next generation is under construction at the Spallation Neutron Source (SNS) in Oak Ridge, USA. A NSE spectrometer measures small velocity changes of the neutrons encoded by the neutrons spin clock at a sample while the Neutron spin precesses in large magnetic fields following Bloch's equation. This instrument will be the best of its class both with respect to resolution and dynamic range. In order to reach this ambitious goal, a large magnetic precision field integral before and after the sample is required which directly scales linearly with the resolution of the instrument. Therefore superconducting technology will be used to allow for a higher magnetic field integral. Here, we present the design, manufacturing and test performance of the solenoids which are the result of a collaboration between Jiilich Research Center (FZJ) and Babcock Noell GmbH (BNG). The solenoids generate an integrated magnetic flux density of 1.8 T*m and use active shielding to reduce the fringe field. The operation temperature of about 4 K is reached by means of pulse-tube coolers in order to minimize vibrations. A special feature of this magnet system is the very accurate measurement of the cold mass-position after cool-down and during operation. The accuracy of this measurement system is in the order of micrometers. This information is required for the adjustment of so called Fresnel coils outside the cryostat. Using these correction elements, a field integral homogeneity better than 10-6 T m for different Neutron paths through one of the solenoids can be achieved.
KW - Hysteresis
KW - Magnetization
KW - Superconducting device fabrication
KW - Superconducting magnets
KW - Superconducting solenoid
UR - http://www.scopus.com/inward/record.url?scp=68649088519&partnerID=8YFLogxK
U2 - 10.1109/TASC.2009.2018782
DO - 10.1109/TASC.2009.2018782
M3 - 文章
AN - SCOPUS:68649088519
VL - 19
SP - 1320
EP - 1323
JO - IEEE Transactions on Applied Superconductivity
JF - IEEE Transactions on Applied Superconductivity
SN - 1051-8223
IS - 3
M1 - 5109561
ER -