When computing the attenuation curve, the bump is now added so that its...

When computing the attenuation curve, the bump is now added so that its relative strength does not depend on δ.

CHANGELOG.md

@@ -16,6 +16,7 @@
 - To accommodate the analysis of the observations by blocks, all models are now included in the estimation of the physical properties and no cut in chi² is done anymore. (Médéric Boquien)
 - To accommodate the analysis of the observations by blocks, the `save_pdf` option has been eliminated. To plot PDF one needs to set `save_chi2` to True and then run `pcigale-plots pdf`. (Médéric Boquien)
 - In order to capture rapid evolutionary phases, we assume that in a given period of 1 Myr, 10 small episodes of star formation occurred every 0.1 Myr, rather than one episode every 1 Myr.
+- When computing the attenuation curve, the bump is now added so that its relative strength does not depend on δ. (Médéric Boquien, issue reported by Samir Salim)
 
 ### Fixed
 - Corrected a typo that prevented `restframe\_parameters` from being listed among the available modules. (Médéric Boquien)

pcigale/sed_modules/dustatt_calzleit.py

@@ -163,8 +163,6 @@ def a_vs_ebv(wavelength, bump_wave, bump_width, bump_ampl, power_slope):
     attenuation[mask] = 0
     # Power law
     attenuation *= power_law(wavelength, power_slope)
-    # UV bump
-    attenuation += uv_bump(wavelength, bump_wave, bump_width, bump_ampl)
 
     # As the powerlaw slope changes E(B-V), we correct this so that the curve
     # always has the same E(B-V) as the starburst curve. This ensures that the
@@ -176,6 +174,11 @@ def a_vs_ebv(wavelength, bump_wave, bump_width, bump_ampl, power_slope):
            uv_bump(wl_BV, bump_wave, bump_width, bump_ampl))
     attenuation *= (EBV_calz[1]-EBV_calz[0]) / (EBV[1]-EBV[0])
 
+    # UV bump. It is added after the renormalization as the bump strength
+    # should correspond to the requested E(B-V) and should therefore not be
+    # changed by the renormalization.
+    attenuation += uv_bump(wavelength, bump_wave, bump_width, bump_ampl)
+
     return attenuation