collaborators

6 papers

hep-ph2026

Natural Phantom Crossing from Axion-WIMP Interactions

Cédric Delaunay, Seung J. Lee, Yuan Yin +1

We construct a technically natural model in which thermal dark matter (DM) interacts with axion dark energy (DE) and produces an apparent late-time crossing of the phantom divide.…

hep-ph2026

Natural Phantom Dark Energy from a --Axion

Cédric Delaunay, Admir Greljo

We present a technically natural microscopic realization of apparent phantom dark energy based on an axion coupled to copies of two-flavor dark QCD related by a

hep-ph2026

Rekindling s-Wave Dark Matter Annihilation Below 10GeV with Breit-Wigner Effects

Geneviève Bélanger, Sreemanti Chakraborti, Cédric Delaunay +1

Velocity-independent (s-wave) annihilation of thermal Dark Matter is ruled out by CMB data for masses below 10GeV, effectively ruling out the possibility of indirectly detecting it…

hep-ph2025

Natural Ultralight Dark Matter: The Quadratic Twin

Cédric Delaunay, Michael Geller, Zamir Heller-Algazi +2

Scalar ultralight dark matter (ULDM) is uniquely accessible to tabletop experiments such as clocks and interferometers, and its search has been the focus of a vast experimental eff…

hep-ph2025

Probing New Forces with Nuclear Clocks

Cédric Delaunay, Seung J. Lee, Roee Ozeri +3

Clocks based on nuclear isomer transitions promise exceptional stability and precision. The low transition energy of the thorium-229 isomer makes it an ideal candidate, as it has b…

hep-ph2025

Light scalar beyond the Higgs mixing limit

Cédric Delaunay, Teppei Kitahara, Yotam Soreq +1

We explore the possibility that the interactions of a light scalar singlet, which mixes with the Standard Model~(SM) Higgs, also receive other UV contributions of comparable size.…