diff --git a/libra_toolbox/neutron_detection/diamond/process_data.py b/libra_toolbox/neutron_detection/diamond/process_data.py
index 806b986..d619568 100644
--- a/libra_toolbox/neutron_detection/diamond/process_data.py
+++ b/libra_toolbox/neutron_detection/diamond/process_data.py
@@ -32,20 +32,26 @@ def get_time_energy_values(
     return time_values, energy_values
 
 
-def main(directory: str, bin_time: int, energy_peak_min: float, energy_peak_max: float):
+def main(
+    directory: str,
+    bin_time: int,
+    energy_peak_min: float,
+    energy_peak_max: float,
+    **kwargs,
+):
     """
 
     Args:
-        directory (str): The directory containing the CSV files.
+        directory (str): The directory containing the CSV files. The csv files should contain times in ps.
         bin_time (int): The time interval to bin the data (s).
         energy_peak_min (float): The minimum energy channel for the (n,alpha) peak.
         energy_peak_max (float): The maximum energy channel for the (n,alpha) peak.
+        kwargs: Additional keyword arguments for get_time_energy_values.
 
     Returns:
         dict: A dictionary containing the time and energy values, as well as the count rates.
     """
-    time_values, energy_values = get_time_energy_values(directory)
-
+    time_values, energy_values = get_time_energy_values(directory, **kwargs)
     # Create a histogram to represent the combined energy spectrum
 
     # sort time and energy values
diff --git a/test/neutron_detection/test_diamond.py b/test/neutron_detection/test_diamond.py
new file mode 100644
index 0000000..5d2cea5
--- /dev/null
+++ b/test/neutron_detection/test_diamond.py
@@ -0,0 +1,139 @@
+from libra_toolbox.neutron_detection.diamond.process_data import *
+import pytest
+
+
+def test_get_avg_neutron_rate():
+
+    time_values = np.arange(1, 10)
+    print(time_values)
+    t_min = 2.5
+    t_max = 9.0
+
+    avg_neutron_rate = get_avg_neutron_rate(time_values, t_min, t_max)
+
+    expected_number_of_counts = 6  # there are 6 counts between 2.5 and 9.0
+
+    expected_avg_neutron_rate = {
+        "counts": expected_number_of_counts,
+        "err": np.sqrt(expected_number_of_counts),
+        "count rate": expected_number_of_counts / (t_max - t_min),
+        "count rate err": np.sqrt(expected_number_of_counts) / (t_max - t_min),
+    }
+
+    assert avg_neutron_rate == expected_avg_neutron_rate
+
+
+@pytest.mark.parametrize("delimiter", [",", ";", "\t"])
+@pytest.mark.parametrize("extention", ["csv", "CSV"])
+def test_get_time_energy_values(tmpdir, delimiter, extention):
+
+    # make data
+    time_values_out = np.random.rand(10)
+    energy_values_out = np.random.rand(10)
+    extra_column = np.random.rand(10)
+
+    # dump 2 columns to the same csv file
+    filename = tmpdir.join(f"test.{extention}")
+    np.savetxt(
+        filename,
+        np.column_stack((time_values_out, energy_values_out, extra_column)),
+        delimiter=delimiter,
+    )
+
+    # read the data back
+    time_values_in, energy_values_in = get_time_energy_values(
+        tmpdir, time_column=0, energy_column=1, delimiter=delimiter
+    )
+
+    assert np.allclose(time_values_in, time_values_out)
+    assert np.allclose(energy_values_in, energy_values_out)
+
+
+def test_main(tmpdir):
+    total_time_s = 100  # s
+    total_time_ps = total_time_s * 1e12  # s to ps
+
+    # peak 1
+    nb_counts_peak1 = int(2e4)
+    size_peak1 = nb_counts_peak1
+    time_values_out_peak1 = np.random.rand(size_peak1) * total_time_ps
+    mean_energy_peak1 = 4e6
+    std_energy_peak1 = 0.1e6
+    energy_values_peak1 = np.random.normal(
+        mean_energy_peak1, std_energy_peak1, size_peak1
+    )
+
+    # make data
+    nb_counts_peak2 = int(7e4)
+    size_peak2 = nb_counts_peak2
+    time_values_out_peak2 = np.random.rand(size_peak2) * total_time_ps
+    mean_energy_peak2 = 14e6
+    std_energy_peak2 = 1e6
+
+    energy_values_peak2 = np.random.normal(
+        mean_energy_peak2, std_energy_peak2, size_peak2
+    )
+
+    # import matplotlib.pyplot as plt
+
+    # plt.hist(energy_values_peak1)
+    # plt.hist(energy_values_peak2)
+    # plt.show()
+
+    filename1 = tmpdir.join(f"peak1.csv")
+    np.savetxt(
+        filename1,
+        np.column_stack((time_values_out_peak1, energy_values_peak1)),
+        delimiter=",",
+    )
+    filename2 = tmpdir.join(f"peak2.csv")
+    np.savetxt(
+        filename2,
+        np.column_stack((time_values_out_peak2, energy_values_peak2)),
+        delimiter=",",
+    )
+
+    # run
+    bin_time = 20  # s
+    res1 = main(
+        tmpdir,
+        bin_time=bin_time,
+        energy_peak_min=mean_energy_peak1 - std_energy_peak1 * 2,
+        energy_peak_max=mean_energy_peak1 + std_energy_peak1 * 2,
+        delimiter=",",
+        time_column=0,
+        energy_column=1,
+    )
+
+    res2 = main(
+        tmpdir,
+        bin_time=bin_time,
+        energy_peak_min=mean_energy_peak2 - std_energy_peak2 * 2,
+        energy_peak_max=mean_energy_peak2 + std_energy_peak2 * 2,
+        delimiter=",",
+        time_column=0,
+        energy_column=1,
+    )
+
+    # test
+    expected_count_rate_total = (nb_counts_peak1 + nb_counts_peak2) / total_time_s
+    expected_count_rate_peak1 = nb_counts_peak1 / total_time_s
+    expected_count_rate_peak2 = nb_counts_peak2 / total_time_s
+
+    assert "all_count_rates" in res1
+    assert "all_count_rate_bins" in res1
+    assert "time_values" in res1
+    assert "energy_values" in res1
+    assert "peak_count_rates" in res1
+    assert "peak_count_rate_bins" in res1
+    assert "peak_time_values" in res1
+
+    # check that the count rates are as expected
+    assert np.allclose(res1["all_count_rates"], expected_count_rate_total, rtol=0.1)
+    assert np.allclose(res1["peak_count_rates"], expected_count_rate_peak1, rtol=0.1)
+
+    assert np.allclose(res2["all_count_rates"], expected_count_rate_total, rtol=0.1)
+    assert np.allclose(res2["peak_count_rates"], expected_count_rate_peak2, rtol=0.1)
+
+    assert len(res1["all_count_rate_bins"]) == total_time_s / bin_time
+    assert len(res2["all_count_rate_bins"]) == total_time_s / bin_time