diff --git a/packages/esssans/docs/user-guide/loki/loki-direct-beam.ipynb b/packages/esssans/docs/user-guide/loki/loki-direct-beam.ipynb
index 26c8b9f99..83e03afc1 100644
--- a/packages/esssans/docs/user-guide/loki/loki-direct-beam.ipynb
+++ b/packages/esssans/docs/user-guide/loki/loki-direct-beam.ipynb
@@ -247,7 +247,7 @@
    "source": [
     "from scipp.scipy.interpolate import interp1d\n",
     "\n",
-    "Iq_theory = sc.io.load_hdf5(loki.data.loki_tutorial_poly_gauss_I0())\n",
+    "Iq_theory = loki.data.loki_tutorial_poly_gauss_I0_data()\n",
     "f = interp1d(Iq_theory, 'Q')\n",
     "I0 = f(sc.midpoints(workflow.compute(QBins))).data[0]\n",
     "I0"
diff --git a/packages/esssans/src/ess/loki/data.py b/packages/esssans/src/ess/loki/data.py
index d92cff38a..c5c65c72c 100644
--- a/packages/esssans/src/ess/loki/data.py
+++ b/packages/esssans/src/ess/loki/data.py
@@ -2,6 +2,8 @@
 # Copyright (c) 2023 Scipp contributors (https://github.com/scipp)
 from pathlib import Path
 
+import numpy as np
+import scipp as sc
 from ess.sans.types import (
     BackgroundRun,
     DirectBeamFilename,
@@ -164,6 +166,31 @@ def loki_tutorial_poly_gauss_I0() -> Path:
     return Path(_registry.get_path('PolyGauss_I0-50_Rg-60.h5'))
 
 
+def loki_tutorial_poly_gauss_I0_data() -> sc.DataArray:
+    """Return the analytical I(Q) model for the tutorial Poly-Gauss sample.
+
+    The model is the SasView ``poly_gauss_coil`` model with an intensity at zero
+    Q of 50, a radius of gyration of 60 angstrom, a polydispersity of 1.02, and
+    a background of 0.2.
+    """
+    q = sc.geomspace(
+        dim='Q',
+        start=0.0005237261180003165,
+        stop=0.5,
+        num=150,
+        unit='1/angstrom',
+    )
+    radius_of_gyration = sc.scalar(60.0, unit='angstrom')
+    # Preserve the float32 parameter values used to compute the original reference.
+    polydispersity = float(np.float32(1.02))
+    background = float(np.float32(0.2))
+
+    u = polydispersity - 1.0
+    z = (q * radius_of_gyration) ** 2 / (1.0 + 2.0 * u)
+    form_factor = 2.0 * ((1.0 + u * z) ** (-1.0 / u) + z - 1.0) / ((1.0 + u) * z**2)
+    return sc.DataArray(50.0 * form_factor + background, coords={'Q': q})
+
+
 def loki_tutorial_direct_beam_all_pixels() -> DirectBeamFilename:
     """File containing direct beam function computed using the direct beam iterations
     notebook, summing all pixels."""
diff --git a/packages/esssans/tests/loki/directbeam_test.py b/packages/esssans/tests/loki/directbeam_test.py
index 15ce38a32..5f087efac 100644
--- a/packages/esssans/tests/loki/directbeam_test.py
+++ b/packages/esssans/tests/loki/directbeam_test.py
@@ -14,7 +14,7 @@
 
 
 def _get_I0(qbins: sc.Variable) -> sc.Variable:
-    Iq_theory = sc.io.load_hdf5(loki.data.loki_tutorial_poly_gauss_I0())
+    Iq_theory = loki.data.loki_tutorial_poly_gauss_I0_data()
     f = interp1d(Iq_theory, 'Q')
     return f(sc.midpoints(qbins)).data[0]