Skip to main content Accessibility help

We use cookies to distinguish you from other users and to provide you with a better experience on our websites. Close this message to accept cookies or find out how to manage your cookie settings.

Close cookie message
×
Hostname: page-component-cd9895bd7-fscjk Total loading time: 0 Render date: 2024-12-27T09:48:14.387Z Has data issue: false hasContentIssue false

6 - NMR Polarization Measurement

Published online by Cambridge University Press:  03 February 2020

Tapio O. Niinikoski
Get access

Summary

The principles of the continuous-wave (CW) NMR techniques is reviewed, as applied to the measurement of the nuclear polarization in polarized targets. The circuit theory of the series-tuned Q-meter is then described in detail in view of calculating precisely the CW NMR absorption signal and its integral, the signal-to-noise ratio, the probe coupling and sampling, and the signal saturation. Optimization of the series-tuned Q-meter circuit is discussed on the basis of the circuit theory. Improved Q-meter circuits will be reviewed, including the capacitively coupled Q-meter, the crossed-coil NMR circuit, and the introduction of quadrature mixer that enables the measurement of the real and imaginary parts of the RF signal simultaneously. Calibration and measurement of very small NMR signals then follows. We also treat the signal-to-noise issues, the electromagnetic interferences, and the NMR circuit drift issues.

Keywords

Transverse susceptibilityabsorption lineLiverpool series Q-metercircuit theorysignal-to-noise ratiosaturationoptimization of Q-meterTE calibrationsuperradiance.
Type
Chapter
Information
The Physics of Polarized Targets , pp. 245 - 282
Publisher: Cambridge University Press
Print publication year: 2020

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Petricek, V., Odehnal, M., Analyse du Q-metre utilise pour des mesures de polarisation nucleaire elevée, Nucl. Instr. and Meth. 52 (1967) 197–201.CrossRefGoogle Scholar
Petricek, V., A linearized Q-meter circuit for measurement of high proton polarization in a target, Nucl. Instr. and Meth. 58 (1968) 111–116.Google Scholar
Udo, F., Some new features in a nuclear magnetic resonance detection system for measuring polarization of highly polarized substances, in: Shapiro, G. (ed.) Proc. 2nd Int. Conf. on Polarized Targets, LBL, University of California, Berkeley, 1971, 397–401.Google Scholar
Boyes, E., Court, G. R., Craven, B. J., Gamet, R., Hayman, P. J., An on-line computer polarization measuring system using R. F. phase lock techniques, in: Shapiro, G. (ed.) Proc. 2nd Int. Conf. on Polarized Targets, LBL, University of California, Berkeley, 1971, 407–410.Google Scholar
Gifford, D., A Q-meter with RF phase sensitive detector, in: Court, G. R., et al. (eds.) Proc. 2nd Workshop on Polarized Target Materials, SRC, Rutherford Laboratory, Chilton, Didcot, 1980, 85–90.Google Scholar
Court, G. R., Gifford, D. W., Harrison, P., Heyes, W. G., Houlden, M. A., A high precision Q-meter for the measurement of proton polarization in polarized targets, Nucl. Instr. and Methods A324 (1993) 433–440.Google Scholar
Niinikoski, T. O., Mathematical treatment of the series Q-meter, in: Court, G. R., et al. (eds.) Proc. of the 2nd Workshop on Polarized Target Materials, SRC, Rutherford Laboratory, Chilton, Didcot, Oxon, UK, 1980, 80–85.Google Scholar
Niinikoski, T. O., Topics in NMR polarization measurement, in: Dutz, H., Meyer, W. (Eds.) Proc. 7th Int. Workshop on Polarized Target Materials and Techniques, Elsevier, Amsterdam, 1995, 62–73.Google Scholar
Niinikoski, T. O., Rijllart, A., An MC68000 microprocessor CAMAC system for NMR measurement of polarization, Nucl. Instrum. Methods 199 (1982) 485–489.Google Scholar
Spin Muon Collaboration (SMC), Adeva, B., Ahmad, S., et al., Measurement of the deuteron polarization in a large target, Nucl. Instr. and Meth. in Phys. Res. A349 (1994) 334–344.Google Scholar
Abragam, A., Goldman, M., Nuclear Magnetism: Order and Disorder, Clarendon Press, Oxford, 1982.Google Scholar
Dhawan, S. K., Understanding effect of teflon room temperature phase transition on cax cable delay in order to improve the measurement of TE signals of deuterated polarized targets, IEEE Trans. Nucl. Sci. 39 (1992) 1331–1335.Google Scholar
Kisselev, Y. F., Dulya, C. M., Niinikoski, T. O., Measurement of complex RF susceptibility using a series Q-meter, Nucl. Instr. and Meth. in Phys. Res. A354 (1994) 249–261.Google Scholar
Preston-Thomas, H., The international temperature scale of 1990 (ITS-90), Metrologia 27 (1990) 3–10.CrossRefGoogle Scholar
Engert, J., Fellmuth, B., Jousten, K., A new 3He vapour-pressure based temperature scale from 0.65 K to 3.2 K consistent with the PLTS-2000, Metrologia 44 (2007) 40–53.Google Scholar
Niinikoski, T. O., Polarized targets at CERN, in: Marshak, M. L. (ed.) Int. Symp. on High Energy Physics with Polarized Beams and Targets, American Institute of Physics, Argonne, 1976, 458–484.Google Scholar
Crabb, D., Dhawan, S., Hayashi, N., Rijllart, A., Noise and stability improvements in the DMR system for SMC, in: Hasegawa, T., et al. (eds.) Proc. 10th Int. Symp. on High-Energy Spin Physics, Universal Academy Press, Inc., Tokyo, 1993, 375–379.Google Scholar
Spin Muon Collaboration (SMC), Adeva, B., Arik, E., et al., Large enhancement of deuteron polarization with frequency modulated microwaves, Nucl. Instrum. and Methods A372 (1996) 339–343.Google Scholar

Save book to Kindle

To save this book to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about saving to your Kindle.

Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

Find out more about the Kindle Personal Document Service.

Available formats
×

Save book to Dropbox

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Dropbox.

Available formats
×

Save book to Google Drive

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.

Available formats
×