In this scenario, voluminous parahydrogen
moderators (two cylinders of 16 cm diameter, 13 cm high) are situated on each side of the target and thus close to the spallation neutron density hotspot.
New fundamental equations of state for parahydrogen
, orthohydrogen and normal hydrogen were developed to replace the previous standards (Younglove 1962).
This equation for parahydrogen
, adapted for use for normal hydrogen, was once considered adequate for density calculations in the region of interest.
Bass, Indiana University 9:20-9:35 Parity-violating neutron spin rotation in a liquid parahydrogen
The input spectrum provided for the bottom, downstream, parahydrogen
moderator is directly along flight-path number 14 and is shown in Fig.
Low energy neutrons depolarize rapidly in orthohydrogen, while those below 15 meV retain their polarization in a parahydrogen
target; hence, it is important to ensure that the liquid hydrogen target is prepared and maintained with the very low equilibrium ortho-hydrogen concentration of 0.1 %.
We describe here an experiment to measure the neutron spin-rotation in a parahydrogen
target (n-p system) using pulsed cold-neutrons from the fundamental symmetries beam line at the Spallation Neutron Source under construction at the Oak Ridge National Laboratory.
Bowman et al., Measurement of the parity-violating gamma asymmetry [A.sub.[gamma]] in the capture of polarized cold neutrons by parahydrogen
, [[right arrow].n] + p [right arrow] d + [gamma], Tech.