Abstract.
Although studied for many years the nature of the light scalar mesons remains controversial. Here we shall present a method, applicable for s-wave states located close to a threshold, that allows one to quantify the molecular part of a given state. When applied to the f 0(980) a dominance of the molecular component is found. In the second part, we show that requirements of field-theoretic consistency and chiral symmetry, when applied to the scattering of light pseudo-scalars, naturally lead to the appearance of dynamical poles in the scalar sector. A program is proposed on how to further investigate experimentally the mixing between these dynamical states and possible genuine quark states.
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References
I. Caprini, G. Colangelo, H. Leutwyler, Phys. Rev. Lett. 96, 132001 (2006) [arXiv:hep-ph/0512364]
D. Morgan, Phys. Lett. B 51, 71 (1974)
E. Van Beveren, T.A. Rijken, K. Metzger, C. Dullemond, G. Rupp, J.E. Ribeiro, Z. Phys. C 30, 615 (1986).
N.A. Tornqvist, M. Roos, Phys. Rev. Lett. 76, 1575 (1996) [arXiv:hep-ph/9511210].
R. Jaffe, Phys. Rev. D 15, 267 (1977)
D. Black, A.H. Fariborz, F. Sannino, J. Schechter, Phys. Rev. D 59, 074026 (1999) [arXiv:hep-ph/9808415].
J. Weinstein, N. Isgur, Phys. Rev. Lett. 48, 659 (1982)
J.A. Oller, E. Oset, J.R. Pelaez, Phys. Rev. Lett. 80, 3452 (1998) [arXiv:hep-ph/9803242].
S. Weinberg, Phys. Rev. 130, 776 (1963)
V. Baru, Phys. Lett. B 586, 53 (2004).
M.R. Pennington, Phys. Rev. Lett. 97, 011601 (2006).
J.L. Rosner, arXiv:hep-ph/0608102.
B. Kerbikov, Phys. Lett. B 596, 200 (2004) [arXiv:hep-ph/0402022].
S. Flatté, Phys. Lett. B 63, 224 (1976).
V. Baru, J. Haidenbauer, C. Hanhart, A. Kudryavtsev, U.G. Meißner, Eur. Phys. J. A 23, 523 (2005) [arXiv:nucl-th/0410099].
BES Collaboration (M. Ablikim), Phys. Lett. B 607, 243 (2005) [arXiv:hep-ex/0411001].
J.R. Pelaez, Phys. Rev. D 55, 4193 (1997) [arXiv:hep-ph/9609427].
S. Weinberg, Phys. Rev. Lett. 17, 616 (1966).
G. Colangelo, J. Gasser, H. Leutwyler, Nucl. Phys. B 603, 125 (2001) [arXiv:hep-ph/0103088].
N.A. Tornqvist, Z. Phys. C 68, 647 (1995) [arXiv:hep-ph/9504372].
E. van Beveren, D.V. Bugg, F. Kleefeld, G. Rupp, arXiv:hep-ph/0606022
N.N. Achasov, G.N. Shestakov, Phys. At. Nucl. 56, 1270 (1993) [Yad. Fiz. 56N9, 206 (1993)].
U.G. Meißner, Comments Nucl. Part. Phys. 20, 119 (1991).
A. Dobado, J.R. Pelaez, Phys. Rev. D 47, 4883 (1993) [arXiv:hep-ph/9301276].
J.R. Pelaez, Mod. Phys. Lett. A 19, 2879 (2004) [arXiv:hep-ph/0411107].
J.R. Pelaez, Phys. Rev. Lett. 92, 102001 (2004) [arXiv:hep-ph/0309292].
D. Lohse, J.W. Durso, K. Holinde, J. Speth, Nucl. Phys. A 516, 513 (1990)
Y. Kalashnikova, A. Kudryavtsev, A.V. Nefediev, J. Haidenbauer, C. Hanhart, Phys. Rev. C 73, 045203 (2006) [arXiv:nucl-th/0512028].
N.N. Achasov, A.V. Kiselev, Phys. Rev. D 73, 054029 (2006) [arXiv:hep-ph/0512047].
R.R. Akhmetshin, Phys. Lett. B 462, 480 (1999).
A. Aloisio, Phys. Lett. B 536, 209 (2002)
E. Marko, S. Hirenzaki, E. Oset, H. Toki, Phys. Lett. B 470, 20 (1999)
V.E. Markushin, Eur. Phys. J. A 8, 389 (2000).
J.A. Oller, Phys. Lett. B 426, 7 (1998)
F.E. Close, N. Isgur, S. Kumano, Nucl. Phys. B 389, 513 (1993).
N.N. Achasov, V.V. Gubin, V.I. Shevchenko, Phys. Rev. D 56, 203 (1997).
Y.S. Kalashnikova, A.E. Kudryavtsev, A.V. Nefediev, C. Hanhart, J. Haidenbauer, Eur. Phys. J. A 24, 437 (2005) [arXiv:hep-ph/0412340].
N.N. Achasov, A.V. Kiselev, arXiv:hep-ph/0606268.
Yu.S. Kalashnikova, A.E. Kudryavtsev, A.V. Nefediev, J. Haidenbauer, C. Hanhart, arXiv:hep-ph/0608191.
G. Isidori, L. Maiani, M. Nicolaci, S. Pacetti, JHEP 0605, 049 (2006) [arXiv:hep-ph/0603241]
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Hanhart, C. Towards an understanding of the light scalar mesons. Eur. Phys. J. A 31, 543–548 (2007). https://doi.org/10.1140/epja/i2006-10193-6
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DOI: https://doi.org/10.1140/epja/i2006-10193-6