All Outputs (146)

MicroMaps: Ontology-driven Semantic Geospatial Data Fusion Approach for IoT Integration and Decision Making in Smart Cities (2025)
Presentation / Conference Contribution
Rayis, A., Ortolani, M., David, R.-M., Hirschi, R., & Misirli, G. (2025, August). MicroMaps: Ontology-driven Semantic Geospatial Data Fusion Approach for IoT Integration and Decision Making in Smart Cities. Presented at 2025 the 9th International Conference on Cloud, Big Data and Communication Systems (ICCBDCS 2025), Manchester

Smart cities generate large amounts of Internet of
Things data from diverse sources, often presented in varying
formats and with inconsistent quality, complicating effective data
management and interoperability. Despite recent advancements
relate... Read More about MicroMaps: Ontology-driven Semantic Geospatial Data Fusion Approach for IoT Integration and Decision Making in Smart Cities.

The impact of wind mass loss on nucleosynthesis and yields of very massive stars at low metallicity (2025)
Preprint / Working Paper
Higgins, E. R., Vink, J. S., Hirschi, R., Laird, A. M., & Sabhahit, G. (2025). The impact of wind mass loss on nucleosynthesis and yields of very massive stars at low metallicity

The chemical feedback from stellar winds in low metallicity (Z) environments is key for understanding the evolution of globular clusters and the early Universe. With disproportionate mass lost from the most massive stars (M > 100Msun), and an excess... Read More about The impact of wind mass loss on nucleosynthesis and yields of very massive stars at low metallicity.

Evolving massive stars to core collapse with GENEC: Extension of equation of state, opacities and effective nuclear network (2025)
Journal Article
Griffiths, A., Aloy, M.-Á., Hirschi, R., Reichert, M., Obergaulinger, M., Whitehead, E. E., Martinet, S., Sciarini, L., Ekström, S., & Meynet, G. (2025). Evolving massive stars to core collapse with GENEC: Extension of equation of state, opacities and effective nuclear network. Astronomy & Astrophysics, 693, Article A93. https://doi.org/10.1051/0004-6361/202451816

Context. Stars with initial mass above roughly 8 M⊙ will evolve to form a core made of iron group elements, at which point no further exothermic nuclear reactions between charged nuclei may prevent the core collapse. Electron capture, neutrino losses... Read More about Evolving massive stars to core collapse with GENEC: Extension of equation of state, opacities and effective nuclear network.

Stellar Evolution and Convection in 3D Hydrodynamic Simulations of a Complete Burning Phase (2024)
Journal Article
Rizzuti, F., Hirschi, R., Varma, V., Arnett, W. D., Georgy, C., Meakin, C., Mocák, M., Murphy, A. S., & Rauscher, T. (2024). Stellar Evolution and Convection in 3D Hydrodynamic Simulations of a Complete Burning Phase. Galaxies, 12(6), 87. https://doi.org/10.3390/galaxies12060087

Our understanding of stellar evolution and nucleosynthesis is limited by the uncertainties coming from the complex multi-dimensional processes in stellar interiors, such as convection and nuclear burning. Three-dimensional stellar models can improve... Read More about Stellar Evolution and Convection in 3D Hydrodynamic Simulations of a Complete Burning Phase.

Grids of stellar models with rotation: VIII. Models from 1.7 to 500 M⊙ at metallicity Z = 10−5 (2024)
Journal Article
Sibony, Y., Shepherd, K. G., Yusof, N., Hirschi, R., Chambers, C., Tsiatsiou, S., Nandal, D., Sciarini, L., Moyano, F. D., Bétrisey, J., Buldgen, G., Georgy, C., Ekström, S., Eggenberger, P., & Meynet, G. (2024). Grids of stellar models with rotation: VIII. Models from 1.7 to 500 M⊙ at metallicity Z = 10−5. Astronomy & Astrophysics, 690, Article A91. https://doi.org/10.1051/0004-6361/202450180

Context. Grids of stellar evolution models with rotation using the Geneva stellar evolution code (GENEC) have been published for a wide range of metallicities.

Aims. We introduce the last remaining grid of GENEC models, with a metallicity of Z = 1... Read More about Grids of stellar models with rotation: VIII. Models from 1.7 to 500 M⊙ at metallicity Z = 10−5.

Entrainment in 3D hydrodynamics simulations of neon burning (2024)
Presentation / Conference Contribution
Rizzuti, F., Hirschi, R., Georgy, C., Arnett, W., Meakin, C., & Murphy, A. S. (2022, August). Entrainment in 3D hydrodynamics simulations of neon burning. Presented at 31st General Assembly of the International Astronomical Union (IAU), Republic of Korea

New Wolf-Rayet wind yields and nucleosynthesis of Helium stars (2024)
Journal Article
Higgins, E. R., Vink, J. S., Hirschi, R., Laird, A. M., & Sander, A. A. C. (2024). New Wolf-Rayet wind yields and nucleosynthesis of Helium stars. Monthly Notices of the Royal Astronomical Society, 533(1), 1095-1110. https://doi.org/10.1093/mnras/stae1853

Strong metallicity-dependent winds dominate the evolution of core He-burning, classical Wolf–Rayet (cWR) stars, which eject both H and He-fusion products such as $^{14}$N, $^{12}$C, $^{16}$O, $^{19}$F, $^{22}$Ne, and $^{23}$Na during their evolution.... Read More about New Wolf-Rayet wind yields and nucleosynthesis of Helium stars.

Rapidly rotating Population III stellar models as a source of primary nitrogen (2024)
Journal Article
Tsiatsiou, S., Sibony, Y., Nandal, D., Sciarini, L., Hirai, Y., Ekström, S., Farrell, E., Murphy, L., Choplin, A., Hirschi, R., Chiappini, C., Liu, B., Bromm, V., Groh, J., & Meynet, G. (2024). Rapidly rotating Population III stellar models as a source of primary nitrogen. Astronomy and Astrophysics, 687, 1-17. https://doi.org/10.1051/0004-6361/202449156

Context. The first stars might have been fast rotators. This would have important consequences for their radiative, mechanical, and chemical feedback.

Aims. We discuss the impact of fast initial rotation on the evolution of massive Population III... Read More about Rapidly rotating Population III stellar models as a source of primary nitrogen.

Shell mergers in the late stages of massive star evolution: new insight from 3D hydrodynamic simulations (2024)
Journal Article
Rizzuti, F., Hirschi, R., Varma, V., Arnett, W. D., Georgy, C., Meakin, C., Mocák, M., Murphy, A. S., & Rauscher, T. (2024). Shell mergers in the late stages of massive star evolution: new insight from 3D hydrodynamic simulations. Monthly Notices of the Royal Astronomical Society, 533(1), 687-704. https://doi.org/10.1093/mnras/stae1778

One-dimensional (1D) stellar evolution models are widely used across various astrophysical fields, however they are still dominated by important uncertainties that deeply affect their predictive power. Among those, the merging of independent convecti... Read More about Shell mergers in the late stages of massive star evolution: new insight from 3D hydrodynamic simulations.

321D modelling of massive stars towards core collapse (2024)
Presentation / Conference Contribution
Raphael, H. (2024, July). 321D modelling of massive stars towards core collapse. Presented at EAS2024/, European Astronomical Society Annual Meeting, Padova, Italy

Massive stars and core-collapse supernovae play a key role in the Universe through their radiative, kinetic and chemical feedback. Given their importance, developing theoretical models of massive stars and their final collapse is critical. Massive st... Read More about 321D modelling of massive stars towards core collapse.

Electron-capture supernovae - Thermonuclear explosion or gravitational collapse? - The fate of sAGB stars on a knife's edge (2024)
Presentation / Conference Contribution
Holas, A., Röpke, F., Jones, S., Hirschi, R., & Keegans, J. (2024, June). Electron-capture supernovae - Thermonuclear explosion or gravitational collapse? - The fate of sAGB stars on a knife's edge. Poster presented at Supernova Remnants III: An Odyssey in Space after Stellar Death, Chania, Crete, Greece

It has long been postulated that the onset of electron captures in degenerate high-density ONe cores of super-AGB stars would trigger a supernova, resulting in a collapse into a neutron star (NS). New models of these so-called electron-capture supern... Read More about Electron-capture supernovae - Thermonuclear explosion or gravitational collapse? - The fate of sAGB stars on a knife's edge.

3D simulations of a neon burning convective shell in a massive star (2024)
Journal Article
Georgy, C., Rizzuti, F., Hirschi, R., Varma, V., Arnett, W. D., Meakin, C., Mocak, M., Murphy, A. S., & Rauscher, T. (2024). 3D simulations of a neon burning convective shell in a massive star. Monthly Notices of the Royal Astronomical Society, 531(4), 4293–4310. https://doi.org/10.1093/mnras/stae1381

The treatment of convection remains a major weakness in the modelling of stellar evolution with one-dimensional (1D) codes. The ever increasing computing power makes now possible to simulate in 3D part of a star for a fraction of its life, allowing u... Read More about 3D simulations of a neon burning convective shell in a massive star.

3D simulations of convective shell Neon-burning in a massive star (2024)
Preprint / Working Paper
Georgy, C., Rizzuti, F., Hirschi, R., Varma, V., D. Arnett, W., Meakin, C., Mocak, M., StJ. Murphy, A., & Rauscher, T. 3D simulations of convective shell Neon-burning in a massive star

The treatment of convection remains a major weakness in the modelling of stellar evolution with one-dimensional (1D) codes. The ever increasing computing power makes now possible to simulate in 3D part of a star for a fraction of its life, allowing u... Read More about 3D simulations of convective shell Neon-burning in a massive star.

Experimental Determination of α Widths of ^{21}Ne Levels in the Region of Astrophysical Interest: New ^{17}O+α Reaction Rates and Impact on the Weak s Process. (2024)
Journal Article
Hammache, F., Adsley, P., Lamia, L., Harrouz, D. S., de Séréville, N., Bastin, B., Choplin, A., Faestermann, T., Fougères, C., Hertenberger, R., Hirschi, R., La Cognata, M., Meyer, A., Palmerini, S., Pizzone, R. G., de Oliveira Santos, F., Romano, S., Tumino, A., & Wirth, H.-F. (2024). Experimental Determination of α Widths of ^{21}Ne Levels in the Region of Astrophysical Interest: New ^{17}O+α Reaction Rates and Impact on the Weak s Process. Physical Review Letters, 132(18), Article 182701. https://doi.org/10.1103/PhysRevLett.132.182701

The efficiency of the weak s process in low-metallicity rotating massive stars depends strongly on the rates of the competing ^{17}O(α,n)^{20}Ne and ^{17}O(α,γ)^{21}Ne reactions that determine the potency of the ^{16}O neutron poison. Their reaction... Read More about Experimental Determination of α Widths of ^{21}Ne Levels in the Region of Astrophysical Interest: New ^{17}O+α Reaction Rates and Impact on the Weak s Process..

Very massive star models: I. Impact of rotation and metallicity and comparisons with observations (2023)
Journal Article
Martinet, S., Meynet, G., Ekström, S., Georgy, C., & Hirschi, R. (2023). Very massive star models: I. Impact of rotation and metallicity and comparisons with observations. Astronomy & Astrophysics, 679, Article A137. https://doi.org/10.1051/0004-6361/202347514

Context. In addition to being spectacular objects, very massive stars (VMSs) are suspected to have a tremendous impact on their environment and on cosmic evolution in general. The nucleosynthesis both during their advanced stages and their final expl... Read More about Very massive star models: I. Impact of rotation and metallicity and comparisons with observations.

The Nuclear Reaction Network WinNet (2023)
Journal Article
Reichert, M., Winteler, C., Korobkin, O., Arcones, A., Bliss, J., Eichler, M., Frischknecht, U., Fröhlich, C., Hirschi, R., Jacobi, M., Kuske, J., Martínez-Pinedo, G., Martin, D., Mocelj, D., Rauscher, T., & Thielemann, F.-K. (2023). The Nuclear Reaction Network WinNet. The Astrophysical Journal Supplement, 268(2), Article 66. https://doi.org/10.3847/1538-4365/acf033

We present the state-of-the-art single-zone nuclear reaction network WinNet, which is capable of calculating the nucleosynthetic yields of a large variety of astrophysical environments and conditions. This ranges from the calculation of the primordia... Read More about The Nuclear Reaction Network WinNet.

Slow Neutron-Capture Process in Evolved Stars (2023)
Book Chapter
Hirschi, R. (2023). Slow Neutron-Capture Process in Evolved Stars. In Handbook of Nuclear Physics (3537-3571). Springer. https://doi.org/10.1007/978-981-19-6345-2_118

The slow neutron-capture process (s process) contributes to the production of roughly half of the elements heavier than iron. The main component of the s process takes place in the late phases (AGB phase) of low-mass stars and is the topic of most re... Read More about Slow Neutron-Capture Process in Evolved Stars.

Stellar wind yields of very massive stars (2023)
Journal Article
Higgins, E. R., Vink, J. S., Hirschi, R., Laird, A. M., & Sabhahit, G. N. (in press). Stellar wind yields of very massive stars. Monthly Notices of the Royal Astronomical Society, 526(1), 534–547. https://doi.org/10.1093/mnras/stad2537

The most massive stars provide an essential source of recycled material for young clusters and galaxies. While very massive stars (VMS, M>100 $\rm {\rm M}_{\odot }$) are relatively rare compared to O stars, they lose disproportionately large a... Read More about Stellar wind yields of very massive stars.

3D stellar evolution: hydrodynamic simulations of a complete burning phase in a massive star (2023)
Journal Article
Rizzuti, F., Hirschi, R., Arnett, W. D., Georgy, C., Meakin, C., Murphy, A. S., Rauscher, T., & Varma, V. (2023). 3D stellar evolution: hydrodynamic simulations of a complete burning phase in a massive star. Monthly Notices of the Royal Astronomical Society, 523(2), 2317-2328. https://doi.org/10.1093/mnras/stad1572

Our knowledge of stellar evolution is driven by one-dimensional (1D) simulations. 1D models, however, are severely limited by uncertainties on the exact behaviour of many multidimensional phenomena occurring inside stars, affecting their structure an... Read More about 3D stellar evolution: hydrodynamic simulations of a complete burning phase in a massive star.

Turbulence and nuclear reactions in 3D hydrodynamics simulations of massive stars (2023)
Journal Article
Rizzuti, F., Hirschi, R., Georgy, C., Arnett, D., Meakin, C., & Murphy, A. (2023). Turbulence and nuclear reactions in 3D hydrodynamics simulations of massive stars. EPJ Web of Conferences, 279, 05001. https://doi.org/10.1051/epjconf/202327905001

Our knowledge of massive star evolution and nucleosynthesis is limited by uncertainties related to multi-dimensional processes taking place in stellar interiors. Recently, theoretical works have started to improve 1D stellar evolution codes through t... Read More about Turbulence and nuclear reactions in 3D hydrodynamics simulations of massive stars.