117 citations · 1k across the 40 of their papers we have counts for
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Anisotropic separate universe : Long-wavelength perturbations and conserved quantities
Daiki Saito, Atsushi Naruko
We investigate the long-wavelength evolution of linear perturbations in a homogeneous and anisotropic background with a scalar field coupled to a vector field. Using the spatial gr…
Primordial black holes from a curvaton: the role of bimodal distributions
Tomotaka Kuroda, Atsushi Naruko, Vincent Vennin +1
We investigate the formation of primordial black holes in curvaton models of inflation, where the curvature perturbation is not only generated by the inflaton but also by a light s…
Unified approach to secondary effects on the CMB B-mode polarization
Toshiya Namikawa, Atsushi Naruko, Ryo Saito +2
We develop a systematic and unified approach to estimate all possible secondary (i.e. non-primordial) nonlinear effects to the cosmic microwave background (CMB) polarization, named…
Probing small-scale non-Gaussianity from anisotropies in acoustic reheating
Atsushi Naruko, Atsuhisa Ota, Masahide Yamaguchi
We give new constraints on small-scale non-Gaussianity of primordial curvature perturbations by the use of anisotropies in acoustic reheating. Mixing of local thermal or local kine…
Anisotropic inflation reexamined: upper bound on broken rotational invariance during inflation
Atsushi Naruko, Eiichiro Komatsu, Masahide Yamaguchi
The presence of a light vector field coupled to a scalar field during inflation makes a distinct prediction: the observed correlation functions of the cosmic microwave background (…
Geodesic "curve"-of-sight formulae for the cosmic microwave background: a unified treatment of redshift, time delay, and lensing
Ryo Saito, Atsushi Naruko, Takashi Hiramatsu +1
In this paper, we introduce a new approach to a treatment of the gravitational effects (redshift, time delay and lensing) on the observed cosmic microwave background (CMB) anisotro…