https://doi.org/10.1140/epjc/s10052-022-10559-8
Regular Article - Theoretical Physics
Reheating constraints on modified single-field natural inflation models
1
Department of Physics, Chongqing Key Laboratory for Strongly Coupled Physics, Chongqing University, 401331, Chongqing, People’s Republic of China
2
Department of Physics, Norwegian University of Science and Technology, Høgskoleringen 5, 7491, Trondheim, Norway
3
School of Science, Chongqing University of Posts and Telecommunications, 400065, Chongqing, People’s Republic of China
Received:
24
April
2022
Accepted:
25
June
2022
Published online:
4
July
2022
In this paper, we discuss three modified single-field natural inflation models in detail, including Special generalized natural inflation model (SNI), extended natural inflation model (ENI) and natural inflation inspired model (NII). We derive the analytical expression of the tensor-to-scalar ratio r and the spectral index 
for those models. Then the reheating temperature 
and reheating duration 
are analytically derived. Moreover, considering the CMB constraints, the feasible space of the SNI model in 
plane is almost covered by that of the NII, which means the NII is more general than the SNI. In addition, there is no overlapping space between the ENI and the other two models in plane, which indicates that the ENI and the other two models exclude each other, and more accurate experiments can verify them. Furthermore, the reheating brings tighter constraints to the inflation models, but they still work for a different reheating universe. Considering the constraints of , r, 
and choosing near the electroweak energy scale, one can find that the decay constants of the three models have no overlapping area and the effective equations of state 
should be within 
for the three models.
© The Author(s) 2022
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
Funded by SCOAP3
