{"doi":"10.3233/xst-221126","title":"Correlation between X-ray tube current exposure time and X-ray photon number in GATE","abstract":"BACKGROUND: X-ray image quality relies heavily on the emitted X-ray photon number which depends on X-ray tube current and exposure time. To accurately estimate the absorbed dose in an imaging protocol, it is better to simulate the X-ray imaging with a Monte Carlo platform such as GATE (Geant4 Application for Tomographic Emission). Although input of GATE is the X-ray photon number of the simulated X-ray tube, it lacks a good way to setup the photon number for a desired X-ray tube current setting. OBJECTIVE: To provide a method to correlate the experimental X-ray tube current exposure time and the X-ray photon number in GATE. METHODS: The accumulated radiation dose of a micro-computed tomography (CT) X-ray tube was recorded at different current exposure times with a general-purpose ion chamber. GATE was used to model the experimental microCT imaging system and calculate the total absorbed dose (cGy) in the sensitive volume of the ion chamber with different X-ray photon numbers. Linear regression models are used to establish a correlation between the estimated X-ray photon number and the X-ray tube settings. At first, one model establishes the relationship between the experimentally measured dose and the X-ray tube setting. Then, another model establishes a relationship between the simulated dose and the X-ray number in GATE. At last, by correlating these two models, a regression model to estimate the X-ray output number from an experimental X-ray tube setting (mAs) is obtained. RESULTS: For a typical micro-CT scan, the X-ray tube is operated at 50 kVp and 0.5 mA for a 500 ms exposure time per projection (0.25 mAs). For these X-ray imaging parameters, the X-ray number per projection is estimated to be 3.613×106 with 1.0 mm Al filter. CONCLUSION: The findings of this work provide an approach to correlate the experimental X-ray tube current exposure time to the X-ray photon number in the GATE simulation of the X-ray tube to more accurately determine radiation dose for an imaging protocol.","journal":"Journal of X-Ray Science and Technology","year":2022,"id":289070,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":5,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9456,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2022-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":816139,"name":"Yile Fang","orcid":"0000-0003-0171-8818","position":1,"is_corresponding":false},{"id":415254,"name":"Changqing Li","orcid":"0000-0003-4237-1494","position":2,"is_corresponding":false},{"id":802414,"name":"Ignacio O. Romero","orcid":null,"position":0,"is_corresponding":true}],"reference_count":29,"raw_metadata":null,"created_at":"2026-07-19T00:30:18.766838Z","pmid":"35466921","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}