ph/0310258. 

[317] R. Allahverdi, K. Enqvist, A. Mazumdar, and A. Perez-Lorenzana, Nucl. Phys. B618 , 277 (2001), hep-ph/0108225. 

[318] K. Benakli and S. Davidson, Phys. Rev. D60 , 025004 (1999), hep-ph/9810280. 

[319] C. Amsler et al. (Particle Data Group), Phys. Lett. B667 , 1 (2008). 

[320] R. H. Cyburt, J. R. Ellis, B. D. Fields, and K. A. Olive, Phys. Rev. D67 , 103521 (2003), astro-ph/0211258. 

[321] A. D. Sakharov, Pisma Zh. Eksp. Teor. Fiz. 5 , 32 (1967). 

[322] V. A. Kuzmin, V. A. Rubakov, and M. E. Shaposhnikov, Phys. Lett. B155 , 36 (1985). 

[323] V. A. Rubakov and M. E. Shaposhnikov, Usp. Fiz. Nauk 166 , 493 (1996), hep-ph/9603208. 

[324] I. Affleck and M. Dine, Nucl. Phys. B249 , 361 (1985). 

[325] M. Dine, L. Randall, and S. D. Thomas, Nucl. Phys. B458 , 291 (1996), hep-ph/9507453. 

[326] M. Dine, L. Randall, and S. D. Thomas, Phys. Rev. Lett. 75 , 398 (1995), hep-ph/9503303. 

[327] M. Fukugita and T. Yanagida, Phys. Lett. B174 , 45 (1986). 

[328] M. A. Luty, Phys. Rev. D45 , 455 (1992). 

[329] M. Flanz, E. A. Paschos, and U. Sarkar, Phys. Lett. B345 , 248 (1995), hep-ph/9411366. 

[330] L. Covi, E. Roulet, and F. Vissani, Phys. Lett. B384 , 169 (1996), hep-ph/9605319. 

[331] W. Buchmuller, R. D. Peccei, and T. Yanagida, Ann. Rev. Nucl. Part. Sci. 55 , 311 (2005), hep-ph/0502169. 

[332] S. Y. Khlebnikov and M. E. Shaposhnikov, Nucl. Phys. B308 , 885 (1988). 

[333] G. F. Giudice, A. Notari, M. Raidal, A. Riotto, and A. Strumia, Nucl. Phys. B685 , 89 (2004), hep-ph/0310123. 

[334] A. Pilaftsis, Phys. Rev. D56 , 5431 (1997), hep-ph/9707235. 

[335] A. Pilaftsis and T. E. J. Underwood, Nucl. Phys. B692 , 303 (2004), hep-ph/0309342. 

[336] G. Lazarides and Q. Shafi, Phys. Lett. B258 , 305 (1991). 

[337] T. Asaka, K. Hamaguchi, M. Kawasaki, and T. Yanagida, Phys. Rev. D61 , 083512 (2000), hep-ph/9907559. 

[338] G. F. Giudice, M. Peloso, A. Riotto, and I. Tkachev, JHEP 08 , 014 (1999), hep-ph/9905242. 

[339] R. Allahverdi and A. Mazumdar, Phys. Rev. D67 , 023509 (2003), hep-ph/0208268. 

[340] R. Allahverdi, B. Dutta, and A. Mazumdar, Phys. Rev. D67 , 123515 (2003), hep-ph/0301184. 

[341] G. Jungman, M. Kamionkowski, and K. Griest, Phys. Rept. 267 , 195 (1996), hep- 

