Measurements of cosmic-ray abundances on balloons are affected by interactions in the residual atmosphere above the balloon .
Corrections for such interactions are particularly important for observations of rare secondary particles such as boron , antiprotons and positrons .
These corrections can either be calculated if the relevant cross sections in the atmosphere are known , or may be empirically determined by extrapolation of the “ growth curves ” , i. e. the individual particle intensities as functions of atmospheric depth .
The growth-curve technique is particularly attractive for long-duration balloon flights where the periodic daily altitude variations permit rather precise determinations of the corresponding particle intensity variations .
We determine growth curves for nuclei from boron ( Z = 5 ) to iron ( Z = 26 ) , using data from the 2006 Arctic balloon flight of the TRACER detector for cosmic-ray nuclei , and we compare the growth curves with predictions from published cross section values .
In general , good agreement is observed .
We then study the boron/carbon abundance ratio and derive a simple and energy-independent correction term for this ratio .
We emphasize that the growth-curve technique can be developed further to provide highly accurate tests of published interaction cross section values .