Electroweak-Interacting Spin-1 Dark Matter and Its Phenomenology

This book offers construction of a renormalizable effective theory of electroweak-interacting spin-1 dark matter (DM). The effective theory realizes minimal but essential features of DM predicted in extra-dimension models, and enables to systematically treat non-perturbative corrections such as the Sommerfeld effects. Deriving an annihilation cross section including the Sommerfeld effects based on the effective theory, the author discusses the future sensitivity of observations to gamma-ray from the Galactic Center. As a result, the author explains the monochromatic gamma-ray signatures originate from two photons (γγ) or photon and Z boson (γZ) produced in the process of DM annihilations, and concludes a possible scenario that unstable neutral spin-1 particles (Z’) appear and results in a spectral peak in addition to the one caused by γγ and γZ channels in gamma-ray observations. If those two spectral peaks are observed, the masses of spin-1 DM and Z’ would be reconstructed.

Motoko Fujiwara is a postdoc researcher at the Technical University of Munich. She received her Bachelor of Science from Keio University in 2014, her Master of Science from Nagoya University in 2017, and her Ph.D. of Science from Nagoya University in 2022 completing the work on electroweak-interacting dark matter. She worked as a postdoc researcher at the University of Tokyo and moved to the current position. Impressed by the fact that microscopic theories of elementary particles dominates macroscopic-scale systems such as the Universe, she focuses on particle physics and particle phenomenology.

Besides scientific research, she is also engaging in science communications. Motivated to promote reality of science and scientists, she organized a voluntary group of students who are interested in science communication and outreach activities, and released online articles to introduce mysteries in the Universe such as dark matter and the matter-antimatter asymmetry. These outreach activities were awarded as Nagoya University President’s Award in March 2022.