254 citations · 1.8k across the 51 of their papers we have counts for
3 papers · 1 filter
Non-thermally trapped inflation by tachyonic dark photon production
Naoya Kitajima, Shota Nakagawa, Fuminobu Takahashi
We show that a dark Higgs field charged under U(1) gauge symmetry is trapped at the origin for a long time, if dark photons are produced by an axion condensate via tachyo…
New scenario of QCD axion clump formation I: Linear analysis
Naoya Kitajima, Kazuhiro Kogai, Yuko Urakawa
The QCD axion acquires the potential through the non-perturbative effect of the QCD matters around the QCD phase transition. During this period, the direct interaction between the…
Primordial black holes in peak theory with a non-Gaussian tail
Naoya Kitajima, Yuichiro Tada, Shuichiro Yokoyama +1
In this paper, we update the peak theory for the estimation of the primordial black hole (PBH) abundance, particularly by implementing the critical behavior in the estimation of th…