Fix: CsI(Tl) non-linear response correction + detector calibration overhaul
Root cause of Am-241 misidentification: the Radiacode 103's CsI(Tl) crystal shifts low-energy peaks upward (59.5 keV → 71.6 keV for Am-241) due to non-proportional scintillation response. The model was trained on theoretical peak positions and couldn't match the shifted real peaks. Changes: - Add inverse CsI(Tl) non-linear correction to inference pipeline (radiacode_monitor.py, web/config.py, test_detection.py) E_apparent = E_true * (1 + 0.37 * exp(-E_true/100)) Corrects channel mapping so peaks appear at theoretical energies - Fix energy calibration: DetectorConfig now uses E = 0.33 + 2.97*ch with 1023 channels, matching the real detector (was energy_min=20, skip_first_channel=True, different channel width) - Add K-escape peaks for CsI(Tl) iodine X-ray escape (E - 28.5 keV) - Add asymmetric peak shapes for low-energy tails (< 200 keV) - Add log1p normalization in dataset and inference (replaces max-norm) - Add background-subtracted training mode (subtract_background flag) - Add low-signal augmentation (0.01-5 Bq activities, 30-300s durations) - Update docker-compose.yml: batch_size=32, duration=30-300s, CSI_NONLINEAR_ALPHA/BETA env vars for detect and web - Web dashboard: apply CsI correction to displayed spectra - Various UI fixes (Chart.js width, zoom/pan, isotope lines) Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
This commit is contained in:
Jacquin Antoine
@ -3,99 +3,77 @@ Detector Configuration Module
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Contains configuration parameters for Radiacode gamma spectrometers
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and other detector settings.
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Energy calibration matches the real Radiacode 103:
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E(keV) = 0.33 + 2.97 * channel_index
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Uses 1023 channels (channel 1023 is overflow, excluded).
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"""
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from dataclasses import dataclass, field
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from typing import Dict, Optional
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from dataclasses import dataclass
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from typing import Dict
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import numpy as np
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@dataclass
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class DetectorConfig:
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"""Configuration for a gamma spectrometer detector."""
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name: str
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# Energy range in keV
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energy_min_kev: float = 20.0
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energy_max_kev: float = 3000.0
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# Number of channels
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num_channels: int = 1024
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# Some devices/software workflows treat channel 0 as unreliable/noisy.
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# This project models "usable" channels by skipping the first raw channel.
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skip_first_channel: bool = True
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name: str
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# Energy calibration: E = calibration_offset + calibration_slope * channel
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# Must match the real detector calibration used in inference.
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calibration_offset_kev: float = 0.33
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calibration_slope_kev: float = 2.97
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# Number of usable channels (1023 for Radiacode, channel 1023 is overflow)
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num_channels: int = 1023
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# FWHM at 662 keV (Cs-137 reference) as fraction
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fwhm_at_662: float = 0.084 # 8.4%
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fwhm_uncertainty: float = 0.003 # ±0.3%
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# Detector crystal type
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crystal_type: str = "CsI(Tl)"
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# Sensitivity: counts per second at 1 μSv/h for Cs-137
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sensitivity_cps_per_usvh: float = 30.0
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# Detector volume in cm³
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detector_volume_cm3: float = 1.0
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def get_channel_width_kev(self) -> float:
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"""Get the width of each channel in keV."""
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return (self.energy_max_kev - self.energy_min_kev) / self.num_channels
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def get_energy_bins(self) -> np.ndarray:
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"""Get array of energy bin centers (keV) for the modeled usable channels."""
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channel_width = self.get_channel_width_kev()
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# Raw device channels are assumed to be 0..num_channels-1 with centers:
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# E_center(k) = E_min + (k + 0.5) * channel_width
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# If we skip the first raw channel (k=0), we model usable channels k=1..num_channels-1.
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start_raw_channel = 1 if self.skip_first_channel else 0
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raw_channels = np.arange(start_raw_channel, self.num_channels, dtype=np.float64)
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return self.energy_min_kev + (raw_channels + 0.5) * channel_width
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def get_energy_bins(self) -> np.ndarray:
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"""Get array of energy bin centers (keV) matching the real detector calibration."""
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channels = np.arange(self.num_channels, dtype=np.float64)
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return self.calibration_offset_kev + self.calibration_slope_kev * channels
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def get_fwhm_at_energy(self, energy_kev: float) -> float:
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"""
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Calculate FWHM at a given energy.
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For scintillators, FWHM scales approximately as sqrt(E).
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FWHM(E) = FWHM_662 * sqrt(662/E) * E / 662 = FWHM_662 * sqrt(E/662)
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FWHM(E) = FWHM_662 * sqrt(E/662)
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"""
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return self.fwhm_at_662 * np.sqrt(662.0 / energy_kev) * energy_kev
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return self.fwhm_at_662 * np.sqrt(energy_kev / 662.0) * 662.0
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def get_sigma_at_energy(self, energy_kev: float) -> float:
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"""
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Get Gaussian sigma at a given energy.
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sigma = FWHM / (2 * sqrt(2 * ln(2))) ≈ FWHM / 2.355
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"""
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"""Get Gaussian sigma at a given energy."""
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fwhm = self.get_fwhm_at_energy(energy_kev)
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return fwhm / 2.355
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def energy_to_channel(self, energy_kev: float) -> int:
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"""Convert energy in keV to modeled usable channel index."""
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channel_width = self.get_channel_width_kev()
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raw_channel = int((energy_kev - self.energy_min_kev) / channel_width)
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if self.skip_first_channel:
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channel = raw_channel - 1
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max_channel = self.num_channels - 2
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else:
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channel = raw_channel
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max_channel = self.num_channels - 1
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return max(0, min(max_channel, channel))
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"""Convert energy in keV to channel index."""
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channel = int((energy_kev - self.calibration_offset_kev) / self.calibration_slope_kev)
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return max(0, min(self.num_channels - 1, channel))
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def channel_to_energy(self, channel: int) -> float:
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"""Convert modeled usable channel index to energy bin center (keV)."""
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channel_width = self.get_channel_width_kev()
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raw_channel = channel + (1 if self.skip_first_channel else 0)
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raw_channel = max(0, min(self.num_channels - 1, int(raw_channel)))
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return self.energy_min_kev + (raw_channel + 0.5) * channel_width
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"""Convert channel index to energy in keV."""
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return self.calibration_offset_kev + self.calibration_slope_kev * channel
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# Pre-defined configurations for Radiacode devices
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RADIACODE_CONFIGS: Dict[str, DetectorConfig] = {
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"radiacode_101": DetectorConfig(
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name="Radiacode 101",
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fwhm_at_662=0.095, # 9.5% (original model, similar to 102)
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fwhm_at_662=0.095, # 9.5%
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fwhm_uncertainty=0.004,
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crystal_type="CsI(Tl)",
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sensitivity_cps_per_usvh=30.0,
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@ -119,8 +97,7 @@ RADIACODE_CONFIGS: Dict[str, DetectorConfig] = {
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),
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"radiacode_103g": DetectorConfig(
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name="Radiacode 103G",
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energy_min_kev=25.0, # Tech spec lists 0.025…3 MeV
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fwhm_at_662=0.074, # 7.4% (GAGG crystal - better resolution)
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fwhm_at_662=0.074, # 7.4% (GAGG crystal)
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fwhm_uncertainty=0.003,
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crystal_type="GAGG(Ce)",
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sensitivity_cps_per_usvh=40.0,
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@ -131,12 +108,12 @@ RADIACODE_CONFIGS: Dict[str, DetectorConfig] = {
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fwhm_at_662=0.084, # 8.4%
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fwhm_uncertainty=0.003,
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crystal_type="CsI(Tl)",
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sensitivity_cps_per_usvh=77.0, # Higher sensitivity
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detector_volume_cm3=2.5, # Larger crystal
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sensitivity_cps_per_usvh=77.0,
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detector_volume_cm3=2.5,
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),
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}
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def get_default_config() -> DetectorConfig:
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"""Get the default detector configuration (Radiacode 103)."""
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return RADIACODE_CONFIGS["radiacode_103"]
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return RADIACODE_CONFIGS["radiacode_103"]
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