Empirical formulae for mass attenuation and energy absorption coefficients from 1 keV to 20 MeVH. C. Manjunatha, L. Seenappa, K. N. Sridhar, N. Sowmya and Chikka HanumantharayappaEur. Phys. J. D, 71 9 (2017) 235DOI: https://doi.org/10.1140/epjd/e2017-70679-7