{"artifact_id":"L1-504","layer":"L1","title":"Quantitative Photoacoustic Tomography (qPAT)","domain":"Medical Imaging","sub_domain":"Quantitative multi-spectral chromophore recovery (multi-physics joint inverse)","physics_fingerprint":{"L_DAG":8.5,"title":"Quantitative Photoacoustic Tomography (qPAT)","domain":"Medical Imaging","carrier":"photon_to_acoustic","primitives":["L.optical_source","L.optical_diffusion","L.beer_lambert","L.thermoelastic_grueneisen","L.acoustic_wave_propagation","L.transducer_detection","int.temporal","int.spectral"],"sub_domain":"Quantitative multi-spectral chromophore recovery (multi-physics joint inverse)","noise_model":"gaussian","problem_class":"nonlinear_inverse","solution_space":"3D_spectral_chromophore_quantitative","difficulty_delta":5,"integration_axis":"spectral_temporal_spatial","sensing_mechanism":"thermoelastic_with_optical_diffusion"},"observable_profile":{"metric":"PSNR_dB","regime":"Existence of recovered 3D multi-spectral absorption coefficient mu_a(r, lambda) is guaranteed within the declared Omega bounds. Uniqueness holds under multi-illumination or multi-wavelength acquisition (Bal-Uhlmann 2010; Bal-Ren 2011); single-illumination single-wavelength qPAT is non-unique due to the multiplicative H = mu_a * Phi coupling and is excluded from the spec range. Stability is moderately conditioned (kappa_eff ~ 40 after model-based reconstruction) — acoustic bandwidth dominates spatial resolution; mu_s_prime_uncertainty dominates absorption-coefficient bias; gruneisen_uncertainty contributes a scaling factor. Joint Hadamard well-posedness for the coupled optical-thermoelastic-acoustic forward is established by Cox-Arridge-Beard (2009), Bal-Uhlmann (2010), Bal-Ren (2011), Tarvainen et al. (2013), and Cox-Tarvainen-Arridge (2014). See joint_well_posedness_references.","secondary":"RMSE_per_chromophore"},"size_tiers":{"center_spec":{"omega":{"H":256,"W":256,"Z":64,"SNR_dB":22,"N_wavelengths":5,"voxel_size_mm":0.2,"lambda_range_nm":[700,900],"speed_of_sound_mps":1500.0,"gruneisen_uncertainty":0.0,"mu_s_prime_uncertainty":0.0,"transducer_bandwidth_MHz":5.0,"transducer_position_error":0.0,"background_absorption_drift":0.0,"light_fluence_inhomogeneity":0.0,"acoustic_speed_heterogeneity":0.0},"input_format":"multi_wavelength_time_resolved_pressure","problem_class":"qpat","forward_operator":"qpat_joint_forward","epsilon_fn_center":"26.0"},"omega_bounds":{"H":[128,512],"W":[128,512],"Z":[32,256],"SNR_dB":[5.0,40.0],"N_wavelengths":[2,16],"voxel_size_mm":[0.05,1.0],"lambda_range_nm":[600,1100],"speed_of_sound_mps":[1400.0,1600.0],"gruneisen_uncertainty":[0.0,0.3],"mu_s_prime_uncertainty":[0.0,0.3],"transducer_bandwidth_MHz":[1.0,30.0],"transducer_position_error":[0.0,0.2],"background_absorption_drift":[0.0,0.2],"light_fluence_inhomogeneity":[0.0,0.4],"acoustic_speed_heterogeneity":[0.0,0.1]},"epsilon_bounds":{"psnr_db":[8.0,45.0]},"allowed_problem_classes":["qpat","qpat_multi_wavelength","qpat_multi_illumination","qpat_chromophore_unmixing"],"allowed_omega_dimensions":["H","W","Z","N_wavelengths","lambda_range_nm","voxel_size_mm","speed_of_sound_mps","transducer_bandwidth_MHz","SNR_dB","mu_s_prime_uncertainty","gruneisen_uncertainty","acoustic_speed_heterogeneity","transducer_position_error","light_fluence_inhomogeneity","background_absorption_drift"],"allowed_forward_operators":["qpat_joint_forward","qpat_two_step_forward","qpat_multi_illumination_forward","qpat_diffusion_approx_forward","qpat_radiative_transfer_forward"]},"hardness_fn":{"type":"epsilon_fn","delta":5,"kappa":300,"metric":"PSNR_dB"},"initiator_dataset":[{"name":"primary","weight":1.0,"ipfs_cid":null,"license_hash":null}],"status":"testnet","staked_pwm":0.0,"chain_hash":"0xc92428e1d5e53fde3daba7c22ca0b6878713dd81dc0efe3ece43825b2119c710","chain_tx_hash":"0x766d26c2ec52e79e19fa7f1da0fa4773c85019d2cc461669a8dacd7962f2adfb","chain_block":41553373}