银河系消光

• u,g,r,i,z 波段的银河系消光

The Galactic extinction in the u band A_u based on the maps of Schlegel et al. (1998, ApJ, 500, 525). For an R_V = 3.1 absorbing medium, the extinctions in the SDSS bands can be expressed as A_x = C_x E(B-V), where x is the filter (ugriz).

values of C_x are 5.155, 3.793, 2.751, 2.086, and 1.479 for ugriz, respectively

A_g, A_r, A_i, and A_z are 0.736, 0.534, 0.405, and 0.287 times A_u.

• IDL中的计算程序

idlutils中的dust_sdssfilter

aval = dust_sdssfilter(dust_getval(l, b, map='IX', /interp), source='Galaxy')