Bare mass effects on the reheating process after inflation

Journal Article · Fri May 24 00:00:00 EDT 2024 · Physical Review. D.

DOI:https://doi.org/10.1103/physrevd.109.103540· OSTI ID:2361176

Clery, Simon ^[1]; Garcia, Marcos A. G. ^[2]; Mambrini, Yann ^[1]; Olive, Keith A. ^[3]

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1. Université Paris-Saclay, Orsay (France)
2. Universidad Nacional Autónoma de México (Mexico)
3. University of Minnesota, Minneapolis, MN (United States)

We consider the effects of a bare mass term for the inflaton, when the inflationary potential takes the form V(Φ)=λΦ^k about its minimum with k ≥ 4. We concentrate on k =4, but discuss general cases as well. Further, we assume $λΦ$$$$^{2}_{end}$$ >> $$m$$$^{2}_{Φ}$$, where Φ_end is the inflaton field value when the inflationary expansion ends. We show that the presence of a mass term (which may be present due to radiative corrections or supersymmetry breaking) can significantly alter the reheating process, as the equation of state of the inflaton condensate changes from w_Φ = $$\frac{1}{3}$$ to w_Φ = 0 when λ⁢Φ² drops below $$m$$$^{2}_{Φ}$$. We show that, for a mass mΦ ≳ 3⁢λ^{$$\frac{1}{4}$$}T_RH, the mass term will dominate at reheating. The value of λ is relatively model independent as it is normalized by the cosmic microwave background perturbation spectrum. For T models of inflation, this leads to m_Φ ≳ T_RH/250. We compute the effects on the reheating temperature for cases where reheating is due to inflaton decay (to fermions, scalars, or vectors) or to inflaton scattering (to scalars or vectors). For scattering to scalars and in the absence of a decay, there is always a residual inflaton background that acts as cold dark matter. In this case, we derive a strong upper limit to the inflaton bare mass which for T models is m_Φ < 350 MeV⁢(T_RH/10¹⁰ GeV)^3/5. We also consider the effect of the bare mass term on the fragmentation of the inflaton condensate.

• Research Organization: University of Minnesota, Minneapolis, MN (United States)
• Sponsoring Organization: CONAHCYT “Ciencia de Frontera”; DGAPA-PAPIIT; Marie Sklodowska-Curie; USDOE
• Grant/Contract Number: SC0011842
• OSTI ID: 2361176
• Alternate ID(s): OSTI ID: 2479333
• Journal Information: Physical Review. D., Journal Name: Physical Review. D. Journal Issue: 10 Vol. 109; ISSN 2470-0010
• Publisher: American Physical Society (APS)
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
Cosmic microwave background
Cosmology
Inflation