TY - JOUR
T1 - Gravitational wave trispectrum in the axion-SU(2) model
AU - Fujita, Tomohiro
AU - Murai, Kai
AU - Obata, Ippei
AU - Shiraishi, Maresuke
N1 - Funding Information:
We would like to thank Eiichiro Komatsu for useful comments. This work was supported by the JSPS KAKENHI Grants No. JP18K13537, JP20H05854 (T. F.) JP20J20248 (K. M.), JP19K14718 (M. S.) and JP20H05859 (M. S. and I. O.). K. M. is also supported by World Premier International Research Center Initiative (WPI Initiative), MEXT, Japan and the Program of Excellence in Photon Science. I. O acknowledges the support from JSPS Overseas Research Fellowship. M. S. acknowledges the Center for Computational Astrophysics, National Astronomical Observatory of Japan, for providing the computing resources of Cray XC50.
Publisher Copyright:
© 2022 IOP Publishing Ltd and Sissa Medialab
PY - 2022/1
Y1 - 2022/1
N2 - We study the trispectrum of the gravitational waves (GWs) generated through the dynamics of an axionic spectator field and SU(2) gauge fields during inflation. In non-Abelian gauge theory, the gauge fields have four-point self-interactions, which induce the tree-level GW trispectrum. We formulate this type of the GW trispectrum including the non-dynamical contributions and evaluate it in the equilateral limit as a unique signal of this model. We find that the ratio of the GW trispectrum to the cube of the scalar power spectrum can be as large as O(106) in the viable parameter space, which could be captured in the CMB observations.
AB - We study the trispectrum of the gravitational waves (GWs) generated through the dynamics of an axionic spectator field and SU(2) gauge fields during inflation. In non-Abelian gauge theory, the gauge fields have four-point self-interactions, which induce the tree-level GW trispectrum. We formulate this type of the GW trispectrum including the non-dynamical contributions and evaluate it in the equilateral limit as a unique signal of this model. We find that the ratio of the GW trispectrum to the cube of the scalar power spectrum can be as large as O(106) in the viable parameter space, which could be captured in the CMB observations.
KW - Gravitational waves / theory
KW - Inflation
KW - Physics of the early universe
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U2 - 10.1088/1475-7516/2022/01/007
DO - 10.1088/1475-7516/2022/01/007
M3 - Article
AN - SCOPUS:85123695292
SN - 1475-7516
VL - 2022
JO - Journal of Cosmology and Astroparticle Physics
JF - Journal of Cosmology and Astroparticle Physics
IS - 1
M1 - 007
ER -