Quantum noise sub-budgets

1. Adds quantum noise sub-budgets. This addresses 1/3 of #51 (closed). Quantum noise can now be broken up into

• AS port vacuum
• Arm loss
• SEC loss
• Filter cavity loss
• Injection loss
• Readout loss
• Quantum quadrature phase noise

2. Changes the quadrature phase noise calculation as described in the comments below. This should close #20 (closed).
3. Removes support for negative RMS phase fluctuations.
4. Removes call to shotrad4 in some cases since this function no longer exists.

The sub-budgets are only implemented for the Cosmic Explorer interferometers since these are the only ones that have any other sub-budgets. Adding sub-budgets to the other interferometers is easy. The CE2 quantum budget is shown below as an example.

gwinc/ifo/noises.py

@@ -166,6 +166,12 @@ def precomp_suspension(f, ifo):
     return pc
 
 
+
+def precomp_quantum(f, ifo):
+    noise_dict = noise.quantum.shotrad(f, ifo)
+    ifo.gwinc.quantum = noise_dict
+
+
 ##################################################
 
 ############################################################
@@ -236,11 +242,14 @@ class QuantumVacuumAS(nb.Noise):
         color='xkcd:emerald green'
     )
 
+    precomp = [
+        precomp_mirror,
+        precomp_power,
+        precomp_quantum
+    ]
+
     def calc(self):
-        precomp_mirror(self.freq, self.ifo)
-        precomp_gwinc(self.freq, self.ifo)
-        noise_dict = noise.quantum.shotrad(self.freq, self.ifo)
-        return noise_dict['asvac']
+        return self.ifo.gwinc.quantum['asvac']
 
 
 class QuantumVacuumArm(nb.Noise):
@@ -252,11 +261,14 @@ class QuantumVacuumArm(nb.Noise):
         color='xkcd:orange brown'
     )
 
+    precomp = [
+        precomp_mirror,
+        precomp_power,
+        precomp_quantum
+    ]
+
     def calc(self):
-        precomp_mirror(self.freq, self.ifo)
-        precomp_gwinc(self.freq, self.ifo)
-        noise_dict = noise.quantum.shotrad(self.freq, self.ifo)
-        return noise_dict['arm']
+        return self.ifo.gwinc.quantum['arm']
 
 
 class QuantumVacuumSRC(nb.Noise):
@@ -268,11 +280,15 @@ class QuantumVacuumSRC(nb.Noise):
         color='xkcd:cerulean'
     )
 
+    precomp = [
+        precomp_mirror,
+        precomp_power,
+        precomp_quantum
+    ]
+
     def calc(self):
-        precomp_mirror(self.freq, self.ifo)
-        precomp_gwinc(self.freq, self.ifo)
         noise_dict = noise.quantum.shotrad(self.freq, self.ifo)
-        return noise_dict['src']
+        return self.ifo.gwinc.quantum['src']
 
 
 class QuantumVacuumFilterCavity(nb.Noise):
@@ -284,11 +300,15 @@ class QuantumVacuumFilterCavity(nb.Noise):
         color='xkcd:goldenrod'
     )
 
+    precomp = [
+        precomp_mirror,
+        precomp_power,
+        precomp_quantum
+    ]
+
     def calc(self):
-        precomp_mirror(self.freq, self.ifo)
-        precomp_gwinc(self.freq, self.ifo)
-        noise_dict = noise.quantum.shotrad(self.freq, self.ifo)
-        # FC0 are the noises from the filter cavity losses and F0_unsqzd_back
+        noise_dict = self.ifo.gwinc.quantum
+        # FC0 are the noises from the filter cavity losses and FC0_unsqzd_back
         # are noises from the unsqueezed vacuum injected at the back mirror
         # Right now there are at most one filter cavity in all the models;
         # if there were two, there would also be FC1 and FC1_unsqzd_back, etc.
@@ -305,11 +325,14 @@ class QuantumVacuumInjection(nb.Noise):
         color='xkcd:fuchsia'
     )
 
+    precomp = [
+        precomp_mirror,
+        precomp_power,
+        precomp_quantum
+    ]
+
     def calc(self):
-        precomp_mirror(self.freq, self.ifo)
-        precomp_gwinc(self.freq, self.ifo)
-        noise_dict = noise.quantum.shotrad(self.freq, self.ifo)
-        return noise_dict['injection']
+        return self.ifo.gwinc.quantum['injection']
 
 
 class QuantumVacuumReadout(nb.Noise):
@@ -321,11 +344,14 @@ class QuantumVacuumReadout(nb.Noise):
         color='xkcd:mahogany'
     )
 
+    precomp = [
+        precomp_mirror,
+        precomp_power,
+        precomp_quantum
+    ]
+
     def calc(self):
-        precomp_mirror(self.freq, self.ifo)
-        precomp_gwinc(self.freq, self.ifo)
-        noise_dict = noise.quantum.shotrad(self.freq, self.ifo)
-        return noise_dict['pd']
+        return self.ifo.gwinc.quantum['pd']
 
 
 class StandardQuantumLimit(nb.Noise):