  The rate of low energy (< 150 MeV) cosmic ray muons was measured at ground
level as a function of several atmospheric parameters. Stopped muons were
detected in a plastic scintillator block and correlations were determined using
a linear regression model. A strong anti-correlation between fractional changes
in the ground-level pressure and stopping muon rate of -3.0 +- 0.5 was found,
and also a -4.1 +- 0.5 anti-correlation with the fractional change in
atmospheric height at 10 kPa pressure. A weak positive correlation with the 10
kPa temperature was also found, but it was shown not to be statistically
significant in our data set. The same analysis was applied to the total rate of
all charged cosmic ray particles detected with the same apparatus, and good
agreement with previous work was seen. The pressure and height correlation
parameters for stopping muons are larger than for the total rate of all charged
particles by factors of about 1.6 and 3.7, respectively.
