The first COHERENT Germanium array detectors have been delivered! This is a 2 kg detector, the first of 8. We will be characterizing this detector and the others as they are delivered, and will then ship them to ORNL for installation in shielding and measurement of CEνNS.
Dr. Longland’s research group and their collaborators at the University of Edinburgh, UK, have recently had their paper on constraining the 25Al+p reaction rate in classical nova explosions. By studying the 25Mg(d,p)26Mg, excited states in the mirror nucleus were populated and neutron spectroscopic factors were extracted. We measured the spectroscopic factor of the key 0+ resonance and set a stringent upper limit on the 1+ resonance. The result of these findings is a dramatic decrease of the reaction rate below 200 MK.
The paper will be published soon in the European Journal of Physics A.
Drs. Albert Young & Kent Leung along with collaborators from the European Spallation Source (Lund, Sweden), Los Alamos National Lab, and Oak Ridge National Lab have published a paper describing their concept of how to produce a next-generation ultracold neutron source. Such a source can be used to dramatically improve ultracold neutron experiments or allow whole new type of experiments that address questions in nuclear and particle physics, cosmology, astrophysics and condensed matter physics.
The paper was featured as a Editor’s pick in the Journal of Applied Physics (https://aip.scitation.org/doi/10.1063/1.5109879). A Scilight article that was published along with it can be found here: https://aip.scitation.org/doi/10.1063/10.0000359
Our paper “A New Cryogenic Apparatus to Search for the Neutron Electric Dipole Moment” was recently published in the Journal of Instrumentation, Vol. 14, P11017, 2019. It can be found here: https://iopscience.iop.org/article/10.1088/1748-0221/14/11/P11017
The apparatus is designed to produce an ultra-high density of ultra-cold neutrons (UNCs), which will be used to constrain the neutron’s electric dipole moment. The design will provide an ultimate statistical uncertainty for the EDM of 2−3× 10−28 e-cm, with anticipated systematic uncertainties below this level.
In spring we completed cryogenic tests outside biological shield at the PULSTAR reactor and started preparations for tests with neutrons. First test in the biological shield is scheduled for themiddle of October. We will check our radiation shielding and probe neutron fluxes at different locations.
We also successfully cooled down our new Electric Dipole Moment (EDM) cryostat with the dilution refrigerator for the first time. Our next cooldown will be this month, and will be the first time with a test SQUID magnetometer installed.
This summer undergraduate Rami Alshoroogi was performing design work and assembling UCN source parts for the PULSTAR ultra-cold neutron source. New graduate students Cole Teander, Matt Morano and Clark Hickman joined our group and completed research projects related to the neutron EDM.
We are also happy to welcome our new postdoc, Tom Rau, who did his PhD at University of Illinois, Urbana-Champaign, IL.