Joint HEP/Theory Seminar: Introducing The Light Dark Matter Experiment (LDMX)

May 11, -
Speaker(s): Craig Group, University of Virginia
The constituents of dark matter are still unknown, and the viable
possibilities span a very large mass range. Specific scenarios for the
origin of dark matter sharpen the focus on a narrower range of masses:
the natural scenario where dark matter originates from thermal contact
with familiar matter in the early Universe requires the DM mass to lie
within about an MeV to 100 TeV. Considerable experimental attention
has been given to exploring Weakly Interacting Massive Particles in
the upper end of this range (few GeV - ~TeV), while the region ~MeV to
~GeV is largely unexplored. Most of the stable constituents of known
matter have masses in this lower range and a thermal origin for dark
matter works in a simple and predictive manner in this mass range as
well. It is therefore a priority to explore. If there is an
interaction between light DM and ordinary matter, as there must be in
the case of a thermal origin, then there necessarily is a production
mechanism in accelerator-based experiments. The most sensitive way,
(if the interaction is not electron-phobic) to search for this
production is to use a primary electron beam to produce DM in
fixed-target collisions. The Light Dark Matter eXperiment (LDMX) is a
planned electron-beam fixed-target missing-momentum experiment that
has unique sensitivity to light DM in the sub-GeV range. I will give
an overview of the status of this proposed experiment.
Sponsor

Physics

Contact

Kate Scholberg