摘要In the standard model, the weak gauge bosons and fermions obtain mass after spontaneous electro-weak symmetry breaking, which is realized by one fundamental scalar field, namely the Higgs field. We study the simplest scalar cold dark matter model in which the scalar cold dark matter also obtains mass by interaction with the weak-doublet Higgs field, in the same way as those of weak gauge bosons and fermions. Our study shows that the correct cold dark matter relic abundance within 3σ uncertainty (0.093 <Ωdm h2 < 0.129) and experimentally allowed Higgs boson mass (114.4≤ mh ≤ 208GeV) constrain the scalar dark matter mass within 48≤e mS ≤78GeV. This result is in excellent agreement with the result of de Boer et al. (50～100GeV). Such a kind of dark matter annihilation can account for the observed gamma rays excess (10σ) at EGRET for nergies above 1GeV in comparison with the expectations from conventional Galactic models. We also investigate other phenomenological consequences of this model. For example, the Higgs boson decays dominantly into scalar cold dark matter if its mass lies within 48～64GeV.
Abstract：In the standard model, the weak gauge bosons and fermions obtain mass after spontaneous electro-weak symmetry breaking, which is realized by one fundamental scalar field, namely the Higgs field. We study the simplest scalar cold dark matter model in which the scalar cold dark matter also obtains mass by interaction with the weak-doublet Higgs field, in the same way as those of weak gauge bosons and fermions. Our study shows that the correct cold dark matter relic abundance within 3σ uncertainty (0.093 <Ωdm h2 < 0.129) and experimentally allowed Higgs boson mass (114.4≤ mh ≤ 208GeV) constrain the scalar dark matter mass within 48≤e mS ≤78GeV. This result is in excellent agreement with the result of de Boer et al. (50～100GeV). Such a kind of dark matter annihilation can account for the observed gamma rays excess (10σ) at EGRET for nergies above 1GeV in comparison with the expectations from conventional Galactic models. We also investigate other phenomenological consequences of this model. For example, the Higgs boson decays dominantly into scalar cold dark matter if its mass lies within 48～64GeV.
[1] Juste A 2005 arXiv:hep-ex/0511025. [2] Barate R et al 2003 Phys. Lett. B 565 61 [3] Eidelman S et al 2004 Phys. Lett. B 592 1 [4] Veltman M J G and Yndurain F J 1989 Nucl. Phys. B 325 1 Silveira V and Zee A 1985 Phys. Lett. B 161 136 McDonald J 1994 Phys. Rev. D 50 3637 Davoudiasl H, Kitano R, Li T and Murayama H 2005 Phys.Lett. B 609 117 [5] Burgess C P, Pospelov M and ter Veldhuis T 2001 Nucl. Phys. B 619 709 [6] de Boer W, Sander C, Gladyshev A V and Kazakov D I 2005 arXiv:astro-ph/0508617 [7] Coleman S R and Weinberg E 1973 Phys. Rev. D 7 1888 [8] Kolb E W and Turner M S 1990 The Early Universe (NewYork: Addison-Wesley) [9] de Boer W, Sander C, Zhukov V, Gladyshev A V and Kazakov D I2005 arXiv:hep-ph/0511154. [10] Djouadi A 2005 arXiv:hep-ph/0503172 and references therein. [11] Zhu S H 2006 Eur. Phys. J. C 47 833 andreferences therein. [12] Bergstrom L, Edsjo J, Gustafsson M and Salati P 2006 JCAP 0605 006 Cesarini A, Fucito F, Lionetto A, Morselli A and Ullio P 2004 Astropart. Phys. 21 267 Bergstrom L, Ullio P and Buckley J H 1998 Astropart. Phys. 9 137 Bottino A, Donato F, Fornengo N and Scopel S 2004 Phys.Rev. D 70 015005
2007, Vol. 24 
