Residual gas sub-budgets and updates

Adds residual gas damping and additional molecular species to the residual gas calculations. The gas scattering and gas damping are now tracked separately for each species in an excess gas sub-budget. The damping calculation is done in the infinite volume limit by default but adds corrections for squeezed film damping if specified in the yaml file. The aLIGO excess gas sub-budget is shown below as an example.

The new yaml file fields are explained in this comment. The yaml files in this merge request are simpler and none of the interferometers include squeezed film damping.

For aLIGO, Aplus, and Voyager, H2, N2, and H2O are considered. The numbers for aLIGO are taken from the link in this comment. The numbers for Aplus and Voyager are copied from aLIGO and should be checked. The Cosmic Explorer interferometers additionally consider CO2 and Ar.

Closes #63 (closed).

gwinc/ifo/noises.py

@@ -903,6 +903,7 @@ class ExcessGasDampingN2(nb.Noise):
         species = self.ifo.Infrastructure.ResidualGas.N2
         return _calc_residual_gas_damping(self.freq, self.ifo, species, sustf)
 
+
 class ExcessGasDampingH2O(nb.Noise):
     """Excess gas damping for H2O
 
@@ -950,26 +951,31 @@ class ExcessGasDampingAr(nb.Noise):
         species = self.ifo.Infrastructure.ResidualGas.Ar
         return _calc_residual_gas_damping(self.freq, self.ifo, species, sustf)
 
+
 def _calc_residual_gas_damping(f, ifo, species, sustf):
     """Redundant calculation of res gas damping for each species
 
     Can get rid of if budgets are calculated at runtime
     """
     squeezed_film = ifo.Infrastructure.ResidualGas.get('SqueezedFilm', None)
-    if squeezed_film:
-        if 'ETM' in squeezed_film and 'ITM' in squeezed_film:
-            n_ETM = noise.residualgas.residual_gas_damping(
-                f, ifo, species, sustf, squeezed_film.ETM)
 
-            n_ITM = noise.residualgas.residual_gas_damping(
-                f, ifo, species, sustf, squeezed_film.ITM)
+    # Calculate squeezed film for ETM and ITM seperately if either is given
+    # explicitly. If only one is given, it is not computed for the other one.
+    if squeezed_film:
+        if ('ETM' in squeezed_film) or ('ITM' in squeezed_film):
+            n = np.zeros_like(f)
+            if 'ETM' in squeezed_film:
+                n_ETM = noise.residualgas.residual_gas_damping(
+                    f, ifo, species, sustf, squeezed_film.ETM)
+                n += 2 * n_ETM
 
-            n = 2 * (n_ETM + n_ITM)
+            if 'ITM' in squeezed_film:
+                n_ITM = noise.residualgas.residual_gas_damping(
+                    f, ifo, species, sustf, squeezed_film.ITM)
 
-        else:
-            n = 4 * noise.residualgas.residual_gas_damping(
-                f, ifo, species, sustf, squeezed_film)
+                n += 2 * n_ITM
 
+    # Otherwise the same calculation is used for both.
     else:
         n = 4 * noise.residualgas.residual_gas_damping(
             f, ifo, species, sustf, squeezed_film)