URANOS - The Ultra Rapid Adaptable Neutron-Only Simulation for Environmental Research

M. Köhli ¹, M. Schrön ², S. Zacharias ², P. Dietrich ², and U. Schmidt ¹

The Monte-Carlo code URANOS was specifically tailored to address the open questions of cosmic-ray neutron sensing for environmental applications (Köhli et al. 2015). The model's designated purpose is the precise description of neutron interactions in nuclear physics, where it is used as a tool to study the response of detectors for time-of-flight based interferometric methods (see Köhli et al. 2016). Recently, the response functions of cosmic-ray neutron detectors have been analysed with URANOS (Köhli et al. 2018). The model is able to predict the response of cosmic-ray neutrons to user-defined and spatially variable conditions in the soil, atmosphere, and biosphere (Schrön et al. 2018a, 2018b). URANOS is very efficient, as it only accounts for the most relevant neutron interaction processes, namely elastic collisions, inelastic collisions, absorption, and evaporation. The main model features are:

• tracking of particle histories from creation to detection (ray-tracing),
• detector representation as layers or cylinders,
• automatic model and material setup based on color codes in 2D bitmap images

Using ENDF/B-VII and JENDL-HE, the model refers to the same physics database as other particle transport codes, like MCNP or Geant4. Nevertheless, this software should be considered as research in progress.

Stay up to date! We'd like to encourage you to subscribe to the mailing list of URANOS users. This way we can inform you about important updates and new features of the software. You can also share your experience or ask questions to the user community by mailing to:
uranos-users@ufz.de

If you use URANOS in a scientific publication, please forward a copy to us. This will help to support the development of URANOS in the future. 

• Francke et al., 2022, "Assessing the feasibility of a directional cosmic-ray neutron sensing sensor for estimating soil moisture", Geosci. Instrum. Methods Data Syst., 11(1), 75-92, doi:10.5194/gi-11-75-2022
• Rasche et al., 2021, "Towards disentangling heterogeneous soil moisture patterns in cosmic-ray neutron sensor footprints", Hydrology and Earth System Sciences, 25, 6547-6566, doi:10.5194/hess-25-6547-2021
• Köhli et al., 2021, "Potential von Impulse-Neutron-Neutron-Logging zur Kampfmitteldetektion", Altlasten Spektrum, 6, 193-198,
• Köhli et al., 2021, "Soil Moisture and Air Humidity dependence of the above-ground cosmic-ray neutron intensity", Frontiers in Water, 2, 1-15, doi:10.3389/frwa.2020.544847
• Badiee et al., 2021, "Using Additional Moderator to Control the Footprint of a COSMOS Rover for Soil Moisture Measurement", Water Resources Research, 57, e2020WR028478, doi:10.1029/2020WR028478
• Weimar et al., 2020, "Large-scale boron-lined neutron detection systems as a 3He alternative for Cosmic Ray Neutron Sensing", Frontiers in Water, 2, 1-16, doi:10.3389/frwa.2020.00016
• Schattan et al. 2019, "Sensing area‐average snow water equivalent with cosmic‐ray neutrons: the influence of fractional snow cover", Water Resources Research, doi:10.1029/2019WR025647
• Dazhi Li et al., 2019, "Can drip irrigation be scheduled with Cosmic-ray Neutron Sensing?", Vadose Zone Journal, doi:10.2136/vzj2019.05.0053
• Schrön et al., 2018 "Cosmic-Ray Neutron Rover Surveys of Field Soil Moisture and the Influence of Roads", Water Resources Research, doi:10.1029/2017WR021719
• Köhli et al., 2018 "Response Functions for Detectors in Cosmic Ray Neutron Sensing", Nucl Instrum Meth A, doi:10.1016/j.nima.2018.06.052
• Schrön et al., 2018 "Intercomparison of Cosmic-Ray Neutron Sensors and Water Balance Monitoring in an Urban Environment", Geosci. Instrum. Method. Data Syst., 7, 83-99, doi:10.5194/gi-7-83-2018
• Schrön et al., 2017 "Improving Calibration and Validation of Cosmic-Ray Neutron Sensors in the Light of Spatial Sensitivity", Hydrol. Earth Syst. Sci., 21, 5009-5030, doi:10.5194/hess-21-5009-2017
• Köhli et al., 2016, "Efficiency and spatial resolution of the CASCADE thermal neutron detector", Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 828, 242–249, doi:10.1016/j.nima.2016.05.014
• Schrön et al.,  2015, “Monitoring Environmental Water with Ground Albedo Neutrons and Correction for Incoming Cosmic Rays with Neutron Monitor Data”. In: 34th International Cosmic-Ray Conference (ICRC 2015). Proceedings of Science.
• Köhli, Schrön, et al., 2015, "Footprint characteristics revised for field-scale soil moisture monitoring with cosmic-ray neutrons", Water Resources Research, 51, 5772–5790, doi:10.1002/2015WR017169