Bumpy inflation from explosive particle production

@misc{lozanov2026bumpy,
  title = {{Bumpy inflation from explosive particle production}},
  author = {Kaloian D. Lozanov and Xavier Pritchard and Misao Sasaki},
  howpublished = {arXiv},
  year = {2026},
  month = sep,
  doi = {10.48550/arxiv.2608.26920},
  eprint = {2608.26920},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2608.26920},
  note = {CC BY 4.0},
}

TY  - UNPB
TI  - Bumpy inflation from explosive particle production
AU  - Kaloian D. Lozanov
AU  - Xavier Pritchard
AU  - Misao Sasaki
PY  - 2026
DA  - 2026/09/11
PB  - arXiv
DO  - 10.48550/arxiv.2608.26920
UR  - https://arxiv.org/abs/2608.26920
AB  - We present a first-principles derivation of an effective inflaton potential with a bumpy feature. We consider the coupling of a spectator field χto the inflaton ϕsuch that χis massive enough for almost all values of ϕ, but becomes massless when the inflaton crossed the value ϕ_\star. This gives rise to a burst of χ-particle production at ϕ=ϕ_\star. By taking the backreaction of the particle production, we obtain a bumpy feature in the effective potential. We discover that for certain choices of the interaction constants and field scale relevant for particle production, the backreaction-induced bumpy effective potential can lead to a sizable enhancement in the curvature perturbation. In particular, the enhancement can be large enough to generate observationally relevant amounts of primordial black holes and stochastic gravitational wave backgrounds.
ER  -