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Pion scattering poles and chiral symmetry restoration

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2007-10
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Fernández Fraile, Daniel
Herruzo, E. T.
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Amer Physical Soc
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Using unitarized chiral perturbation theory methods, we perform a detailed analysis of the π π scattering poles f_0(600) and ρ(770) behavior when medium effects such as temperature or density drive the system towards chiral symmetry restoration. In the analysis of real poles below threshold, we show that it is crucial to extend properly the unitarized amplitudes so that they match the perturbative Adler zeros. Our results do not show threshold enhancement effects at finite temperature in the f_0(600) channel, which remains as a pole of broad nature. We also implement T=0 finite-density effects related to chiral symmetry restoration, by varying the pole position with the pion decay constant. Although this approach takes into account only a limited class of contributions, we reproduce the expected finite-density restoration behavior, which drives the poles towards the real axis, producing threshold enhancement and π π bound states. We compare our results with several model approaches and discuss the experimental consequences, both in relativistic heavy ion collisions and in π -> π π and γ -> π π reactions in nuclei.
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© 2007 The American Physical Society. We are grateful to J. R. Peláez, G. Ríos and R. García Martín for very useful comments and discussions. We also acknowledge financial support from the Spanish research projects FPA2004-02602, FPA2005-02327, PR27/05- 13955-BSCH, UCM-CAM 910309 and from the F. P. I. programme (BES-2005-6726).
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[1] W. M. Yao et al. (Particle Data Group), J. Phys. G 33, 1 (2006). [2] T. Hatsuda and T. Kunihiro, Phys. Rev. Lett. 55, 158 (1985). [3] S. Chiku and T. Hatsuda, Phys. Rev. D 57, R6 (1998). [4] T. Hatsuda, T. Kunihiro, and H. Shimizu, Phys. Rev. Lett. 82, 2840 (1999). [5] D. Jido, T. Hatsuda, and T. Kunihiro, Phys. Rev. D 63, 011901(R) (2000). [6] K. Yokokawa, T. Hatsuda, A. Hayashigaki, and T. Kunihiro, Phys. Rev. C 66, 022201(R) (2002). [7] D. Davesne, Y. J. Zhang, and G. Chanfray, Phys. Rev. C 62, 024604 (2000). [8] A. Patkos, Z. Szep, and P. Szepfalusy, Phys. Rev. D 66, 116004 (2002). [9] P. Schuck, W. Norenberg, and G. Chanfray, Z. Phys. A330, 119 (1988). [10] A. Patkos, Z. Szep, and P. Szepfalusy, Phys. Rev. D 68, 047701 (2003). [11] Y. Hidaka, O. Morimatsu, T. Nishikawa, and M. Ohtani, Phys. Rev. D 68, 111901(R) (2003). [12] Y. Hidaka, O. Morimatsu, T. Nishikawa, and M. Ohtani, Phys. Rev. D 70, 076001 (2004). [13] L. Roca, E. Oset, and M. J. Vicente Vacas, Phys. Lett. B 541, 77 (2002). [14] H. C. Chiang, E. Oset, and M. J. Vicente-Vacas, Nucl. Phys. A644, 77 (1998); D. Cabrera, E. Oset, and M. J. Vicente Vacas, Phys. Rev. C 72, 025207 (2005). [15] F. Bonutti et al. (CHAOS collaboration), Nucl. Phys. A 677, 213 (2000). [16] A. Starostin et al. (Crystal Ball Collaboration), Phys. Rev. Lett. 85, 5539 (2000). [17] J. G. Messchendorp et al., Phys. Rev. Lett. 89, 222302 (2002). [18] J. Gasser and H. Leutwyler, Phys. Lett. B 184, 83 (1987). [19] P. Gerber and H. Leutwyler, Nucl. Phys. B321, 387 (1989). [20] A. Dobado and J. R. Pela´ez, Phys. Rev. D 59, 034004 (1998); J. R. Peláez, Phys. Rev. D 66, 096007 (2002). [21] T. N. Truong, Phys. Rev. Lett. 61, 2526 (1988); 67, 2260 (1991); A. Dobado, M. J. Herrero, and T. N. Truong, Phys. Lett. B 235, 134 (1990). [22] A. Dobado and J. R. Peláez, Phys. Rev. D 47, 4883 (1993); 56, 3057 (1997). [23] J. A. Oller, E. Oset, and J. R. Peláez, Phys. Rev. Lett. 80, 3452 (1998). [24] A. Gómez Nicola and J. R. Peláez, Phys. Rev. D 65, 054009 (2002). [25] A. Gómez Nicola, F. J. Llanes-Estrada, and J. R. Pela´ez, Phys. Lett. B 550, 55 (2002). [26] A. Dobado, A. Gómez Nicola, F. J. Llanes-Estrada, and J. R. Peláez, Phys. Rev. C 66, 055201 (2002). [27] J. Gasser and H. Leutwyler, Ann. Phys. (N.Y.) 158, 142 (1984). [28] S. Weinberg, Phys. Rev. Lett. 17, 616 (1966). [29] H. A. Weldon, Phys. Rev. D 28, 2007 (1983); Ann. Phys. (N.Y.) 214, 152 (1992). [30] N. Kaiser, Phys. Rev. C 59, 2945 (1999). [31] C. Amsler and N. A. Tornqvist, Phys. Rep. 389, 61 (2004). [32] H. A. Weldon, Ann. Phys. (N.Y.) 228, 43 (1993). [33] D. V. Bugg, Phys. Lett. B 572, 1 (2003). [34] A. Gómez Nicola, J. R. Peláez, and G. Rios (unpublished). [35] R. Delbourgo and M. D. Scadron, Mod. Phys. Lett. A 10, 251 (1995). [36] J. R. Peláez, Phys. Rev. Lett. 92, 102001 (2004); Mod. Phys. Lett. A 19, 2879 (2004). [37] R. L. Jaffe, arXiv:hep-ph/0701038. [38] M. Gell-Mann, R. J. Oakes, and B. Renner, Phys. Rev. 175, 2195 (1968). [39] D. Toublan, Phys. Rev. D 56, 5629 (1997). [40] A. Schenk, Phys. Rev. D 47, 5138 (1993). [41] R. D. Pisarski, Phys. Rev. D 52, R3773 (1995); V. Koch and C. Song, Phys. Rev. C 54, 1903 (1996); C. Song and V. Koch, Phys. Rev. C 54, 3218 (1996); R. Rapp and J. Wambach, Eur. Phys. J. A 6, 415 (1999); Adv. Nucl. Phys. 25, 1 (2002); H.-J. Schulze and D. Blaschke, Phys. Lett. B 386, 429 (1996); Phys. Part. Nucl. Lett. 1, 70 (2004); H. van Hees and R. Rapp, Phys. Rev. Lett. 97, 102301 (2006). [42] A. Gómez Nicola, F. J. LLanes-Estrada, and J. R. Peláez, Phys. Lett. B 606, 351 (2005). [43] G. Agakichiev et al. (CERES Collaboration), Eur. Phys. J. C 41, 475 (2005). [44] R. Arnaldi et al. (NA60 Collaboration), Phys. Rev. Lett. 96, 162302 (2006). [45] J. Adams et al. (STAR Collaboration), Phys. Rev. Lett. 92, 092301 (2004). [46] G. E. Brown and M. Rho, Phys. Rev. Lett. 66, 2720 (1991). [47] M. Harada and C. Sasaki, Phys. Rev. D 74, 114006 (2006). [48] G. E. Brown and M. Rho, Phys. Rep. 363, 85 (2002). [49] H. van Hees and R. Rapp, arXiv:hep-ph/0604269. [50] G. E. Brown and M. Rho, arXiv:nucl-th/0509001; arXiv:nucl-th/0509002. [51] V. Thorsson and A. Wirzba, Nucl. Phys. A589, 633 (1995); U. G. Meissner, J. A. Oller, and A. Wirzba, Ann. Phys. (N.Y.) 297, 27 (2002). [52] R. D. Pisarski and M. Tytgat, Phys. Rev. D 54, R2989 (1996). [53] J. Gasser, H. Leutwyler, and M. E. Sainio, Phys. Lett. B 253, 252 (1991). [54] C. García-Recio, J. Nieves, and E. Oset, Phys. Lett. B 541, 64 (2002). [55] M. J. Vicente Vacas and E. Oset, arXiv:nucl- th/0204055. [56] G. E. Brown and M. Rho, Phys. Rep. 396, 1 (2004).
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