TY - JOUR

T1 - Halo formation from Yukawa forces in the very early Universe

AU - Domènech, Guillem

AU - Inman, Derek

AU - Kusenko, Alexander

AU - Sasaki, Misao

N1 - Funding Information: We thank Elisa G. M. Ferreira, Marcos Flores, Lauren Pearce, Javier Rubio, Volodymyr Takhistov, Edoardo Vitagliano, Christof Wetterich and Graham White for valuable discussions. G. D. is supported by the DFG under the Emmy-Noether program Grant No. DO 2574/1-1, Project No. 496592360. This work was supported by the World Premier International Research Center Initiative (WPI), MEXT, Japan and by Japan Society for the Promotion of Science (JSPS) KAKENHI Grant No. JP20H05853. A. K. was also supported by the U.S. Department of Energy (DOE) Grant No. DE-SC0009937. This work made use of n um p y , s ci p y , m atplotlib and NASA’s Astrophysics Data System Bibliographic Services.

PY - 2023/11/29

Y1 - 2023/11/29

N2 - If long-range attractive forces exist and are stronger than gravity then cosmic halo formation can begin in the radiation-dominated era. We study a simple realization of this effect in a system where dark matter fermions have Yukawa interactions mediated by scalar particles, analogous to the Higgs boson in the standard model. We develop a self-consistent description of the system including exact background dynamics of the scalar field, and precise modeling of the fermion density fluctuations. For the latter, we provide accurate approximations for the linear growth as well as quantitative modeling of the nonlinear evolution using N-body simulations. We find that halo formation occurs exponentially fast and on scales substantially larger than simple estimates predict. The final fate of these halos remains uncertain, but could be annihilation, dark stars, primordial black holes, or even the existence of galaxy-sized halos at matter-radiation equality. More generally, our results demonstrate the importance of mapping scalar-mediated interactions onto structure formation outcomes and constraints for beyond the standard model theories.

AB - If long-range attractive forces exist and are stronger than gravity then cosmic halo formation can begin in the radiation-dominated era. We study a simple realization of this effect in a system where dark matter fermions have Yukawa interactions mediated by scalar particles, analogous to the Higgs boson in the standard model. We develop a self-consistent description of the system including exact background dynamics of the scalar field, and precise modeling of the fermion density fluctuations. For the latter, we provide accurate approximations for the linear growth as well as quantitative modeling of the nonlinear evolution using N-body simulations. We find that halo formation occurs exponentially fast and on scales substantially larger than simple estimates predict. The final fate of these halos remains uncertain, but could be annihilation, dark stars, primordial black holes, or even the existence of galaxy-sized halos at matter-radiation equality. More generally, our results demonstrate the importance of mapping scalar-mediated interactions onto structure formation outcomes and constraints for beyond the standard model theories.

UR - http://www.scopus.com/inward/record.url?scp=85179955039&partnerID=8YFLogxK

U2 - 10.48550/arXiv.2304.13053

DO - 10.48550/arXiv.2304.13053

M3 - Article

AN - SCOPUS:85179955039

VL - 108

JO - Physical Review D

JF - Physical Review D

SN - 2470-0010

IS - 10

M1 - 103543

ER -