diff --git a/modelsusceptcontrasts.py b/modelsusceptcontrasts.py
index 78d7f0c..cddeea5 100644
--- a/modelsusceptcontrasts.py
+++ b/modelsusceptcontrasts.py
@@ -34,7 +34,8 @@ def plot_chi2(ax, s, data_file, rate):
     alpha = data['alpha']
     freqs = data['freqs']
     pss = data['pss']
-    chi2 = np.abs(data['prss'])*0.5/np.sqrt(pss.reshape(1, -1)*pss.reshape(-1, 1))
+    prss = data['prss']
+    chi2 = np.abs(prss)*0.5/(pss.reshape(1, -1)*pss.reshape(-1, 1))
     ax.set_visible(True)
     ax.set_aspect('equal')
     i0 = np.argmin(freqs < -fcutoff)
diff --git a/modelsusceptlown.py b/modelsusceptlown.py
index 9fdb121..a3289f7 100644
--- a/modelsusceptlown.py
+++ b/modelsusceptlown.py
@@ -31,7 +31,8 @@ def plot_chi2(ax, s, data_file, rate):
     alpha = data['alpha']
     freqs = data['freqs']
     pss = data['pss']
-    chi2 = np.abs(data['prss'])*0.5/np.sqrt(pss.reshape(1, -1)*pss.reshape(-1, 1))
+    prss = data['prss']
+    chi2 = np.abs(prss)*0.5/(pss.reshape(1, -1)*pss.reshape(-1, 1))
     ax.set_visible(True)
     ax.set_aspect('equal')
     i0 = np.argmin(freqs < -fcutoff)
diff --git a/modelsusceptovern.py b/modelsusceptovern.py
index aeaae02..d79c916 100644
--- a/modelsusceptovern.py
+++ b/modelsusceptovern.py
@@ -26,8 +26,8 @@ def plot_chi2(ax, s, data_file):
     alpha = data['alpha']
     freqs = data['freqs']
     pss = data['pss']
-    dt_fix = 1 # 0.0005
-    prss = np.abs(data['prss'])/dt_fix*0.5/np.sqrt(pss.reshape(1, -1)*pss.reshape(-1, 1))
+    prss = data['prss']
+    chi2 = np.abs(prss)/0.5/(pss.reshape(1, -1)*pss.reshape(-1, 1))
     ax.set_visible(True)
     ax.set_aspect('equal')
     i0 = np.argmin(freqs < -300)
@@ -36,8 +36,8 @@ def plot_chi2(ax, s, data_file):
     if i1 == 0:
         i1 = len(freqs)
     freqs = freqs[i0:i1]
-    prss = prss[i0:i1, i0:i1]
-    vmax = np.quantile(prss, 0.996)
+    chi2 = chi2[i0:i1, i0:i1]
+    vmax = np.quantile(chi2, 0.996)
     ten = 10**np.floor(np.log10(vmax))
     for fac, delta in zip([1, 2, 3, 4, 6, 8, 10],
                           [0.5, 1, 1, 2, 3, 4, 5]):
@@ -45,7 +45,7 @@ def plot_chi2(ax, s, data_file):
             vmax = fac*ten
             ten *= delta
             break
-    pc = ax.pcolormesh(freqs, freqs, prss, vmin=0, vmax=vmax,
+    pc = ax.pcolormesh(freqs, freqs, chi2, vmin=0, vmax=vmax,
                        rasterized=True)
     ax.set_title(f'$N=10^{np.log10(n):.0f}$', fontsize='medium')
     ax.set_xlim(0, 300)
@@ -77,8 +77,8 @@ def plot_overn(ax, s, files, nmax=1e6, title=False):
         alpha = data['alpha']
         freqs = data['freqs']
         pss = data['pss']
-        dt_fix = 1 # 0.0005
-        chi2 = np.abs(data['prss'])/dt_fix*0.5/np.sqrt(pss.reshape(1, -1)*pss.reshape(-1, 1))
+        prss = data['prss']
+        chi2 = np.abs(prss)/0.5/(pss.reshape(1, -1)*pss.reshape(-1, 1))
         ns.append(n)
         i0 = np.argmin(freqs < 0)
         i1 = np.argmax(freqs > 300)
diff --git a/noisesplit.py b/noisesplit.py
index 2ba4604..2801eab 100644
--- a/noisesplit.py
+++ b/noisesplit.py
@@ -83,8 +83,8 @@ def plot_overn(ax, s, files, nmax=1e6):
         alpha = data['alpha']
         freqs = data['freqs']
         pss = data['pss']
-        dt_fix = 1 # 0.0005
-        chi2 = np.abs(data['prss'])/dt_fix*0.5/np.sqrt(pss.reshape(1, -1)*pss.reshape(-1, 1))
+        prss = data['prss']
+        chi2 = np.abs(prss)/0.5/(pss.reshape(1, -1)*pss.reshape(-1, 1))
         ns.append(n)
         i0 = np.argmin(freqs < 0)
         i1 = np.argmax(freqs > fcutoff)
@@ -131,7 +131,8 @@ def plot_chi2_contrast(ax1, ax2, s, files, nums, nsmall, nlarge, rate):
         alpha = data['alpha']
         freqs = data['freqs']
         pss = data['pss']
-        chi2 = np.abs(data['prss'])*0.5/np.sqrt(pss.reshape(1, -1)*pss.reshape(-1, 1))
+        prss = data['prss']
+        chi2 = np.abs(prss)*0.5/(pss.reshape(1, -1)*pss.reshape(-1, 1))
         cax = plot_chi2(ax, s, freqs, chi2, n, rate)
         cax.set_ylabel('')
         print(f'Modeled  cell {"-".join(files[i].name.split("-")[2:-2])} at {100*alpha:4.1f}% contrast: noise_frac={1:3.1f}, nsegs={n}')
@@ -147,7 +148,8 @@ def plot_chi2_split(ax1, ax2, s, files, nums, nsmall, nlarge, rate):
         noise_frac = data['noise_frac']
         freqs = data['freqs']
         pss = data['pss']
-        chi2 = np.abs(data['prss'])*0.5/np.sqrt(pss.reshape(1, -1)*pss.reshape(-1, 1))
+        prss = data['prss']
+        chi2 = np.abs(prss)*0.5/(pss.reshape(1, -1)*pss.reshape(-1, 1))
         cax = plot_chi2(ax, s, freqs, chi2, n, rate)
         cax.set_ylabel('')
         print(f'Modeled  cell {"-".join(files[i].name.split("-")[2:-1])} at {100*alpha:4.1f}% contrast: noise_frac={noise_frac:3.1f}, nsegs={n}')
@@ -169,7 +171,8 @@ def plot_chi2_data(ax, s, cell_name, run):
     alpha = data['alpha']
     freqs = data['freqs']
     pss = data['pss']
-    chi2 = np.abs(data['prss'])*0.5/np.sqrt(pss.reshape(1, -1)*pss.reshape(-1, 1))
+    prss = data['prss']
+    chi2 = np.abs(prss)*0.5/(pss.reshape(1, -1)*pss.reshape(-1, 1))
     print(f'Measured cell {"-".join(data_file.name.split("-")[:-2])} at {100*alpha:4.1f}% contrast: r={ratebase:3.0f}Hz, CV={cvbase:4.2f}, dt={1000*deltat:4.2f}ms, nfft={nfft}, win={1000*deltat*nfft:6.1f}ms, nsegs={n}')
     print()
     plot_chi2(ax, s, freqs, chi2, n, ratebase)
diff --git a/punitexamplecell.py b/punitexamplecell.py
index ea2ab8f..e8045fc 100644
--- a/punitexamplecell.py
+++ b/punitexamplecell.py
@@ -76,7 +76,7 @@ def load_spectra(path, cell_name, run=None):
     prss = data['prss']
     nsegs = int(data['n'])
     gain = np.abs(prs)/pss
-    chi2 = np.abs(prss)*0.5/np.sqrt(pss.reshape(1, -1)*pss.reshape(-1, 1))
+    chi2 = np.abs(prss)*0.5/(pss.reshape(1, -1)*pss.reshape(-1, 1))
     return fcutoff, contrast, freqs, gain, chi2