Prospects for detecting axionlike particles at the Coherent CAPTAIN-Mills experiment
Abstract
We show results from the Coherent CAPTAIN Mills (CCM) 2019 engineering run which begin to constrain regions of parameter space for axion-like particles (ALPs) produced in electromagnetic particle showers in an 800 MeV proton beam dump, and further investigate the sensitivity of ongoing data-taking campaigns for the CCM200 upgraded detector. Based on beam-on background estimates from the engineering run, we make realistic extrapolations for background reduction based on expected shielding improvements, reduced beam width, and analysis-based techniques for background rejection. We obtain reach projections for two classes of signatures; ALPs coupled primarily to photons can be produced in the tungsten target via the Primakoff process, and then produce a gamma-ray signal in the Liquid Argon (LAr) CCM detector either via inverse Primakoff scattering or decay to a photon pair. ALPs with significant electron couplings have several additional production mechanisms (Compton scattering, annihilation, ALP-bremsstrahlung) and detection modes (inverse Compton scattering, external pair conversion, and decay to ). In some regions, the constraint is marginally better than both astrophysical and terrestrial constraints. With the beginning of a three year run, CCM will be more sensitive to this parameter space by up to an order of magnitude for both ALP-photon and ALP-electron couplings. The CCM experiment will also have sensitivity to well-motivated parameter space of QCD axion models. It is only a recent realization that accelerator-based large volume liquid argon detectors designed for low energy coherent neutrino and dark matter scattering searches are also ideal for probing ALPs in the unexplored MeV mass scale.
Keywords
Cite
@article{arxiv.2112.09979,
title = {Prospects for detecting axionlike particles at the Coherent CAPTAIN-Mills experiment},
author = {A. A. Aguilar-Arevalo and D. S. M. Alves and S. Biedron and J. Boissevain and M. Borrego and L. Bugel and M. Chavez-Estrada and J. M. Conrad and R. L. Cooper and A. Diaz and J. R. Distel and J. C. D'Olivo and E. Dunton and B. Dutta and D. Fields and J. R. Gochanour and M. Gold and E. Guardincerri and E. C. Huang and N. Kamp and D. Kim and K. Knickerbocker and W. C. Louis and J. T. M. Lyles and R. Mahapatra and S. Maludze and J. Mirabal and N. Mishra and D. Newmark and P. deNiverville and V. Pandey and D. Poulson and H. Ray and E. Renner and T. J. Schaub and A. Schneider and M. H. Shaevitz and D. Smith and W. Sondheim and A. M. Szelc and C. Taylor and A. Thompson and W. H. Thompson and M. Tripathi and R. T. Thornton and R. Van Berg and R. G. Van de Water and S. Verma},
journal= {arXiv preprint arXiv:2112.09979},
year = {2023}
}
Comments
Accepted for publication in Physical Review D, in production