The COHERENT effort to measure coherent, elastic neutrino-nucleus scattering: status and enabling measurements
The COHERENT Collaboration seeks to make an unambiguous, first observation of the coherent, elastic neutrino-nucleus scattering (CEvNS) process using a suite of detector technologies and leveraging the intense, pulsed neutrino source afforded by the Spallation Neutron Source (SNS) of Oak Ridge National Laboratory. Still unobserved over 40 years after its prediction, measurements of CEvNS could ultimately be associated with a broad complement of physics, including nuclear structure, supernova models, and sterile-neutrino searches, as well as serving as a basic test of, and possibly a probe for evidence of physics beyond, the standard model. Owing to the experimental challenges that have precluded the detection of CEvNS thus far, COHERENT has undertaken several ancillary experimental campaigns. Like many direct searches for dark matter, observation of CEvNS relies on the detection of low-energy nuclear recoils; consequently, careful measurements of the low-energy quenching factors (QFs) for nuclear recoils in detector media are essential. Using a pulsed, quasi-monoenergetic neutron beam at Triangle Universities Nuclear Laboratory (TUNL), measurements of the QF in CsI[Na] and NaI[Tl], of particular interest to the dark-matter community, have been carried out. This talk will discuss the status of COHERENT and the enabling measurements necessary for its success, with a particular focus on, and preliminary results from, the QF measurement campaign at TUNL.