Abstract
Recent developments in the theory of heavy quarks have increased the prospects for the study of non-perturbative QCD in the weak decays of heavy mesons and baryons and for the reliable determination of some of the parameters of the Standard Model. It has been made possible due to the discovery of a spin-flavour symmetry for heavy quarks which arises in QCD when quark mass is taken to infinity. Certain properties in hadrons containing a heavy quark then become independent of its mass and spin. These ideas have tremendous impact on the phenemenology of heavy hadrons. In particular, these symmetries give rise to restrictive relations among weak decay amplitudes and reduce the number of independent form factors. By relating various matrix elements and fixing normalization of some matrix elements, the heavy quark symmetry has enhanced our predictive ability, allowing in some cases to bypass the difficulties of understanding hadronic structure.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
R.L. Kingley et al., Phys. Rev.D11 (1975) 1919; A. Ali, J. G. Korner and G. Kramers, Z. Phys.C11 (1981) 21; D. Zeppenfeld, Z. Phys.C8 (1981) 77; M. J. Savage and M. B. Wise, Phys. Rev.D39 (1989) 3346; M. J. Savage and M. B. Wise, Nucl. Phys.B326 (1989) 15; M. J. Savage and M. B. Wise, Phys. Rev.D42 (1990) 1527; Rajesh Arora, Gurpreet Kaur Sidana and M. P. Khanna, Phys. Rev.D45 (1992) 4121. There are many other papers on the subject. For a review on charmed baryons see J. G. Körner and H. Siebert, Annual Rev. Nucl. Part. Sc. (1992) to be published.
N. Isgur and M. B. wise, Phys. Lett.B232 (1989) 113;B237 (1990) 527; There are now several lecture notes which discuss in detail the ideas, calculational methods and results of the new (so called Isgur-Wise) symmetry. They are: J. D. Bjorken, SLAC-Report 378 in Proc. 18th SLAC Summer Institute of Particle Physics (1990) ed. by J. F. Hawthorne. H. Georgi, Lectures at TASI, HUTP-91-Aoel (1991). B. Grinstein, HUTP-91-A040, SSCL-Preprint 17 (1991). T. Mannel, Heavy Quark Effective Theory, IKDA 92/6, Jan. 92. Inst. Kernphysik, Tech. Hochschule, Darmstadt. M. B. Wise, CALT-68-1721 Lectures at Lake Louise Winter Institute (1991).
M. Voloshin and M Shifman, Sov. J. Nucl. Phys.45 (1987) 292;47 (1988) 511; E. Eichten and B. Hill, Phys. Lett.B234 (1990) 511; H. Politzer and M. B. Wise, Phys. Lett.B206 (1988) 681;B208 (1988) 504; H. Georgi, Phys. Lett.B240 (1990) 447.
N. Isgur and M. B. Wise, Nucl. Phys.B348 (1991) 276.
H. Georgi, Nucl. Phys.B348 (1991) 293.
B. Grinstein, Nucl. Phys.B339 (1990) 253; A. Falk, H. Georgi, B Grinstein and M. B. wise, Nucl. Phys.B343 (1990) 1; A. Falk and B. Grinstein, Phys. Lett.B247 (1990) 406.
J. Bjorken, SLAC preprint SLAB-PUB 5278 (1990); A. Acker, S. Pakvasa, S. F. Tuan and S. P. Rosen, Phys. Rev.D43 (1991) 3083.
F. Hussain, J. G. Körner, M. Kramer and G. Thompson, Z. Phys.C51 (1991) 321; J. G. Körner and G. Thompson, Phys. Lett.B264 (1991) 185.
M. E. Luke, Phys. LettB252 (1990) 447; A. F. Falk, B. Grinstein and M. E. Luke, Nucl. Phys.B357 (1991) 185.
T. Mannel, W. Roberts and Z. Ryzak, Nucl. Phys.B355 (1991) 38.
T. Mannel, W. Roberts and Z. Ryzak, Phys. Lett.B248 (1990) 392;B254 (1991) 274;B255 (1991) 593;B259 (1991) 359;B259 (1991) 485.
H. Georgi, B. Grinstein and M. B. Wise, Phys. Lett.B252 (1990) 456; A. F. Falk, B. Grinstein and M. E. Luke, Nucl. Phys.B357 (1991) 185.
M. Neubert, Phys. Lett.B264 (1991) 455.
M. Wirbel, B. Stech and M. Bauer, Z. Phys.C29 (1985) 637; M. Bauer, B. Stech and M. Wirbel, Z. Phys.C3 (1987) 103; W. A. Bardeen, A. J. Buras and J. M. Gerard, Phys. Lett.B180 (1987) 133; Nucl. Phys.B293 (1987) 787.
P. Avery et al. Phys. Rev.D43 (1991) 3599.
The ARGUS Collaboration, DESY 91-091, August 1991.
M. Dugan and B. Grinstein, Phys. Lett.B255 (1990) 583.
S. Pakvasa, S. F. Tuan and S. P. Rosen, Phys. RevD42 (1990) 3746.
Gurpreet Kaur and M. P. Khanna, Phys. Rev.D43 (1991) 182.
M. A. Shifman, in Lepton and Photon Interaction, proceedings of the International Symposium on Lepton and Photon Interactions at High Energies, Hamburg, Germany, 1987, ed. R. Ruckl and W. Bartel.
Gurpreet Kaur and M. P. Khanna, Phys. Rev.D45 (1992) R3024.
Particle Data Group, J. J. Hernandez et al., Phys. Lett.B239 (1991) 1.
M. Neubert, Phys. Rev.D45 (1992) 2451; Phys. Rev.D46 (1992) 1076; E. Bagan, P. Ball, V. M. Braun and H. G. Dosh, Phys. Lett.B278 (1992) 457; A. V. Radyushkin, Phys. Lett.B271 (1991) 2189; M. Neubert, V. Rieckert, B. Stech, and Q. P. Xu inHeavy Flavours, ed. by A. J. Buras and M. Linder, Advanced series on Directions in High Energy physics (world scientific, Singapore, 1992); A. F. Falk and M. Neubert, Second Order Power Corrections in the Heavy Quark Effective Theory, SLAC-PUB-5897, 1992; SLAC-PUB-5898, 1992.
T. Mannel, W. Roberts and Z. Ryzak, Phys. Rev.D45 (1992) 875.
M. Neubert, Z. Ligeti and Y. Nir, SLAC-PUB-5915, 1992; B. Blok and M. Shifman, Santa Barbara Preprint NSF-IT-P-92-100, 1992; For introduction to 1/MQ corrections see the appendix.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Khanna, M.P. Flavour-spin symmetry and weak decays of heavy hadrons. Pramana - J. Phys. 41 (Suppl 1), 217–233 (1993). https://doi.org/10.1007/BF02908085
Issue Date:
DOI: https://doi.org/10.1007/BF02908085