TY - JOUR
T1 - Gravitino production from heavy moduli decay and cosmological moduli problem revived
AU - Nakamura, Shuntaro
AU - Yamaguchi, Masahiro
N1 - Funding Information:
The authors would like to thank T. Asaka, T. Moroi, Y. Shimizu, and A. Yotsuyanagi for useful discussions. The work was partially supported by the grants-in-aid from the Ministry of Education, Science, Sports, and Culture of Japan, Nos. 16081202 and 17340062.
PY - 2006/7/20
Y1 - 2006/7/20
N2 - The cosmological moduli problem for relatively heavy moduli fields is reinvestigated. For this purpose we examine the decay of a modulus field at a quantitative level. The modulus dominantly decays into gauge bosons and gauginos, provided that the couplings among them are not suppressed in the gauge kinetic function. Remarkably the modulus decay into a gravitino pair is unsuppressed generically, with a typical branching ratio of order 0.01. Such a large gravitino yield after the modulus decay causes cosmological difficulties. The constraint from the big-bang nucleosynthesis pushes up the gravitino mass above 105 GeV. Furthermore to avoid the over-abundance of the stable neutralino lightest superparticles (LSPs), the gravitino must weigh more than about 106 GeV for the wino-like LSP, and even more for other neutralino LSPs. This poses a stringent constraint on model building of low-energy supersymmetry.
AB - The cosmological moduli problem for relatively heavy moduli fields is reinvestigated. For this purpose we examine the decay of a modulus field at a quantitative level. The modulus dominantly decays into gauge bosons and gauginos, provided that the couplings among them are not suppressed in the gauge kinetic function. Remarkably the modulus decay into a gravitino pair is unsuppressed generically, with a typical branching ratio of order 0.01. Such a large gravitino yield after the modulus decay causes cosmological difficulties. The constraint from the big-bang nucleosynthesis pushes up the gravitino mass above 105 GeV. Furthermore to avoid the over-abundance of the stable neutralino lightest superparticles (LSPs), the gravitino must weigh more than about 106 GeV for the wino-like LSP, and even more for other neutralino LSPs. This poses a stringent constraint on model building of low-energy supersymmetry.
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U2 - 10.1016/j.physletb.2006.05.078
DO - 10.1016/j.physletb.2006.05.078
M3 - Article
AN - SCOPUS:33745497197
SN - 0370-2693
VL - 638
SP - 389
EP - 395
JO - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
JF - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
IS - 5-6
ER -