[ { "question_id": "initial", "original_label": "initial", "question": "Transmission to nadir at 550 km versus overhead cloud optical depth; cloud-top/above-top source; Rayleigh versus particles.", "notebooks": [ "01", "02" ], "remaining_gaps": [ "Event-specific cloud geometry, overhead gas/aerosol/ozone columns, source angular emission and absolute photon output.", "Validated ice phase/absorption properties and actual aperture/field/time acceptance." ], "source_ids": [ "CT003", "CT029", "CT041", "CT045", "CT048", "R4-CLOUDSCAT" ] }, { "question_id": "A1", "original_label": "1", "question": "Which radiative-transfer calculation/tool should be used, and alternatives to CloudScat?", "notebooks": [ "02" ], "remaining_gaps": [ "A matched independent transient benchmark using the same real-ice properties and detector estimator.", "A validated event-specific source/cloud model." ], "source_ids": [ "CT004", "CT020", "CT021", "CT022", "CT034", "CT053", "R4-CLOUDSCAT" ] }, { "question_id": "A2", "original_label": "2", "question": "Multiple scattering and temporal profile; robustness of 30-80 us versus>200 us rise-time discrimination.", "notebooks": [ "02", "03", "04" ], "remaining_gaps": [ "Consistent rise definitions and independently labeled source depths/classes.", "Intrinsic pulse families, realistic cloud phases/geometry and calibrated receiver response/noise.", "Injection-recovery over actual leading-edge counts, background, sample phase and count losses." ], "source_ids": [ "CT044", "DO-ELEC-MMIA-ARCH", "DO-ELEC-SAMPLING-MT002", "DO-RAD-ANISIMOVA2017", "airfly-quenching-physics", "bai2023-bath-waveform", "li2021-shallow-fast", "li2022-multipulse" ] }, { "question_id": "B4", "original_label": "4", "question": "Absolute nightside 337 nm radiance: quiet airglow, moon, zodiacal light and integrated starlight.", "notebooks": [ "01" ], "remaining_gaps": [ "A total 337 nm scene distribution with measured components and geometry at high latitudes.", "Actual filter/field response, cloud directional reflection and gas transmission." ], "source_ids": [ "BG017", "BG027", "BG028", "BG035", "BG048", "BG049", "BG059" ] }, { "question_id": "B5", "original_label": "5", "question": "Auroral 337 nm 4 nm-band brightness and shot-noise floor during moderate/disturbed conditions.", "notebooks": [ "01", "03" ], "remaining_gaps": [ "A calibrated 4 nm 337 nm radiance/time distribution for the actual high-latitude field and scene.", "Precipitation spectra, arc filling, cloud transfer and actual detector end-of-life noise." ], "source_ids": [ "BG006", "BG019", "BG021", "BG023", "BG062", "BG063", "BG064" ] }, { "question_id": "B6", "original_label": "6", "question": "Lunar phase/elevation at which cloud background dominates detector noise.", "notebooks": [ "01" ], "remaining_gaps": [ "Validated 337 nm lunar irradiance versus phase/libration and cloud illumination geometry.", "Chosen receiver noise/temperature, spectral-angular response and cloud reflection." ], "source_ids": [ "BG012", "BG013", "BG015", "BG016", "BG025", "BG038", "BG039", "BG040" ] }, { "question_id": "C7", "original_label": "7", "question": "Detector choice at 337 nm, large area and 10-50 kHz; claimed photodiode/TIA floor.", "notebooks": [ "01", "03" ], "remaining_gaps": [ "Selected sensor/package 337 nm PDE or responsivity, actual sensitive area/capacitance and bias/temperature-dependent dark PSD or correlated-count distribution", "Complete readout noise, impulse response, power and permitted readout mode; for CMOS, measured full accepted-area cadence and summed read noise, not minimum exposure alone" ], "source_ids": [ "DO-DET-GSENSE400", "DO-DET-S13360-AREA", "DO-DET-S8664-LARGE", "DO-DET-SISMUV2025", "DO-ELEC-ADI2015", "DO-ELEC-TIA-BAILEY2026", "DO-WIDEGAP-SG01D" ] }, { "question_id": "C8", "original_label": "8", "question": "NEP and aperture photons per event for candidate detectors.", "notebooks": [ "01", "03" ], "remaining_gaps": [ "Actual receiver spectral noise/count statistics, gain/excess noise and target-band throughput at beginning/end of life", "Injection-recovery versus aperture photon fluence under relevant backgrounds, integration windows, pulse shapes and false-trigger rules" ], "source_ids": [ "DO-DET-S13360-AREA", "DO-ELEC-ADC-ENBW2019", "DO-ELEC-APD-NOISE", "DO-ELEC-FEMTO-DLPCA", "DO-METHOD-NEP2025", "EU-lcsur" ] }, { "question_id": "C9", "original_label": "9", "question": "DC coupling and preservation of a>3 ms pulse.", "notebooks": [ "01" ], "remaining_gaps": [ "Full-chain optical impulse/step and>3 ms pulse response across faint/background/overload conditions", "Droop, pedestal, saturation, recovery, discrimination/dead time and pulse-phase bias with actual ADC integration/filtering" ], "source_ids": [ "DO-ELEC-CALIOP-TRANSIENT2026", "DO-ELEC-ET-DC", "DO-ELEC-MMIA-ARCH", "DO-RAD-ANISIMOVA2017", "EU-etbase" ] }, { "question_id": "C10", "original_label": "10", "question": "2-3 year 550 km polar/SAA radiation effects on dark current and gain.", "notebooks": [], "remaining_gaps": [ "Selected device/lot pre/post proton, TID and SEE tests at intended temperatures, including PDE/gain, noise PSD/DCR, correlated noise and annealing limits", "Prompt particle/window/coating/electronic pulse shapes and false-event/veto response of the assembled head" ], "source_ids": [ "DO-PARTICLE-ICECUBE2011", "DO-PARTICLE-TUS2021", "DO-RAD-ANISIMOVA2017", "DO-RAD-DSOUZA2021", "DO-RAD-GRB2025", "DO-RAD-GRID2022", "DO-RAD-SPOOQY2025", "DO-RAD-ULTRASATTID2023" ] }, { "question_id": "C11", "original_label": "11", "question": "European suppliers for flight or near-flight detectors.", "notebooks": [], "remaining_gaps": [ "Part/lot-specific spectral calibration at 337/777 and accepted qualification/acceptance results for the actual detector, base, HV and readout build" ], "source_ids": [ "EU-et9111", "EU-et9113", "EU-etbase", "EU-etprecautions", "EU-excelfactory", "EU-fsapd", "EU-fsesa", "EU-lcfactory", "EU-lcsur", "EU-photekds", "EU-uvit" ] }, { "question_id": "D12", "original_label": "12", "question": "Maximise nonimaging photometer etendue within roughly 1U.", "notebooks": [ "01" ], "remaining_gaps": [ "Assembled field/pupil/wavelength response, vignetting, detector illumination uniformity, throughput and baffle/stray-light rejection" ], "source_ids": [ "DO-DET-GLIMS2011", "DO-ELEC-MMIA-ARCH", "DO-OPT-ETENDUE1985" ] }, { "question_id": "D13", "original_label": "13", "question": "Maintain narrowband filter response over 60-90 degree full field.", "notebooks": [ "01" ], "remaining_gaps": [ "Filter transmission map versus wavelength, actual ray angle/cone, polarization, temperature and vacuum for the selected coating", "Full-field assembled spectral response including pupil weighting and tolerances" ], "source_ids": [ "DO-ELEC-MMIA-ARCH", "DO-OPT-ALLUXA-THERMAL2014", "DO-OPT-LIS2000" ] }, { "question_id": "D14", "original_label": "14", "question": "Is 4 nm FWHM optimal for the N2(0, 0)band and background?", "notebooks": [ "01" ], "remaining_gaps": [ "Representative source-band spectra or validated physical spectral model constrained by source conditions", "Scene/background spectra and actual assembled filter/detector response with stable wavelength registration" ], "source_ids": [ "BG035", "BG048", "BG054", "BG055", "BG056", "BG057", "DO-OPT-ALLUXA337" ] }, { "question_id": "D15", "original_label": "15", "question": "Required optical density and rejection wavelength range.", "notebooks": [ "01" ], "remaining_gaps": [ "Dynamic-range-qualified leak/blocking scan through detector cutoff, including pinholes, angle/polarization/thermal changes and induced fluorescence", "Scene spectra sufficient to bound out-of-band photoelectrons and stray light under permitted night/Moon/twilight conditions" ], "source_ids": [ "BG035", "BG038", "DO-OPT-ALLUXA337", "DO-OPT-SOPAPILLA2026", "DO-PARTICLE-TUS2021", "juice2026-majis-spectra" ] }, { "question_id": "E16", "original_label": "16", "question": "777.4 nm null-channel detector and comparable photon thresholds.", "notebooks": [ "01", "03" ], "remaining_gaps": [ "Both full-chain photon-scale spectral/field response, background/noise, live time and impulse response, including dead time, saturation and recovery", "Red-channel upper-limit coverage and joint false-negative/false-classification performance using calibrated injections and representative source controls" ], "source_ids": [ "DO-DATA-LEAL2026", "DO-DET-H16722-RED", "DO-DET-S8664-LARGE", "DO-ELEC-MMIA-ARCH", "DO-PARTICLE-TUS2021", "DO-RAD-ANISIMOVA2017", "chuang2022-catalogue-actual-joint-flags" ] }, { "question_id": "E17", "original_label": "17", "question": "Cross-calibration of different detector technologies for a trustworthy ratio.", "notebooks": [ "01", "03" ], "remaining_gaps": [ "Traceable common-source calibration across each channel spectrum, field, pulse fluence and operating temperature with overlapping attenuation ranges", "Relative delay/IRF and systematic covariance, plus repeated stability checks and independent reference monitoring" ], "source_ids": [ "DO-CAL-CALSPEC2026", "DO-CAL-NPL-ANALOG2026", "DO-ELEC-MMIA-ARCH", "DO-ELEC-SOPAPILLA2026", "DO-OPT-NIST-WAVELENGTH" ] }, { "question_id": "F18", "original_label": "18", "question": "On-orbit gain drift, absolute radiometric stability and peak brightness versus current.", "notebooks": [], "remaining_gaps": [ "Independent optical reference/monitor stability and full-path throughput/PDE drift at science wavelengths, with separate multiplication-gain and offset diagnostics", "If using stars, actual attitude/path/field response and differential-background covariance; if inferring current, independent current/radio-optical/source-condition calibration" ], "source_ids": [ "DO-CAL-CALSPEC2026", "DO-CAL-ISUAL2012", "DO-CAL-JENKINS2026", "DO-CAL-OMI2022", "DO-CAL-OMPS2023", "DO-CAL-SALDANHA2017", "airfly-quenching-physics", "guo2025-independent-streamer-field", "pervez2024-current-inverse" ] }, { "question_id": "F19", "original_label": "19", "question": "Ground calibration/characterisation and facilities.", "notebooks": [], "remaining_gaps": [ "Configuration-specific traceable spectral/angular/pulsed receiver calibration with stated uncertainty", "Noise/linearity/trigger/timing/bright-light recovery, environmental qualification and contamination/radiation tests for selected build" ], "source_ids": [ "DO-CAL-ESA-OOEL", "DO-CAL-NIST2007", "DO-CAL-NPL-ANALOG2026", "DO-CAL-PTB340-2024", "DO-CAL-SALDANHA2017", "DO-OPT-NIST-WAVELENGTH" ] }, { "question_id": "F20", "original_label": "20", "question": "Laboratory 337 nm source with 30 us rise and>3 ms duration.", "notebooks": [ "01", "02" ], "remaining_gaps": [ "Optical waveform measured by a sufficiently fast reference at actual drive/temperature: 30 us rise, >3 ms duration, stability and recovery", "Spectrum/filter capture and calibrated attenuation from faint through overload, with stray-light control" ], "source_ids": [ "DO-CAL-AUGER2009", "DO-CAL-ICECUBE337-2010", "DO-CAL-LEDD1B", "DO-CAL-M340L5" ] }, { "question_id": "G21", "original_label": "21", "question": "Can 2-4 kg/5-10 W deliver a useful event rate at 550 km?", "notebooks": [ "03", "04" ], "remaining_gaps": [ "Faint source/dual-band population with calibrated completeness and non-detections.", "Packaged optical/electronic/thermal/power design, field response, backgrounds and end-of-life injection-recovery.", "Actual orbit/time/exposure, health/safing, telemetry and false-classification controls." ], "source_ids": [ "DO-ELEC-MMIA-ARCH", "ahmad2014-2015-uppsala-opposing-evidence", "bai2023-bath-waveform", "bath2023-context-waveform", "bitzer2026-group-matching", "night-selection-layer-shadow", "soler2022-peak-bins" ] }, { "question_id": "G22", "original_label": "22", "question": "What assumptions or physics are missing?", "notebooks": [ "00", "01", "02", "03", "04" ], "remaining_gaps": [ "Selected receiver calibration and end-of-life response.", "Realistic source/cloud/noise classes and independent physical labels.", "Unbiased joint population/exposure and validated operational false-event control." ], "source_ids": [ "DO-CAL-SALDANHA2017", "DO-ELEC-MMIA-ARCH", "DO-PARTICLE-ICECUBE2011", "DO-PARTICLE-TUS2021", "R4-CLOUDSCAT", "bai2023-bath-waveform", "chuang2022-catalogue-actual-joint-flags", "pervez2024-current-inverse" ] } ]