# Publications

Here is a non-exhaustive list of publications that employ the pCI software package.

## 2024
- **pCI: a parallel configuration interaction software package for high-precision atomic structure calculations**, Charles Cheung, Mikhail G. Kozlov, Sergey G. Porsev, Marianna S. Safronova, Ilya I. Tupitsyn, Andrey I. Bondarev, *[arXiv:2410.06680 (2024)](https://arxiv.org/abs/2410.06680)*.
- **A neural network approach to running high-precision atomic computations**, Pavlo Bilous, Charles Cheung, and Marianna S. Safronova, *[arXiv:2408.00477 (2024)](https://arxiv.org/abs/2408.00477)*.
- **Pr<sup>10+</sup> as a candidate for a high-accuracy optical clock for tests of fundamental physics**, S.G. Porsev, C. Cheung, M.S. Safronova, H. Bekker, N.-H. Rehbehn, J. R. Crespo Lopez-Urrutia, S. M. Brewer, *[arXiv:2407.17610 (2024)](https://arxiv.org/abs/2407.17610)*.
- **Prospects of a thousand-ion Sn2+ Coulomb-crystal clock with sub-10-19 inaccuracy**, David R. Leibrandt, Sergey G. Porsev, Charles Cheung, and Marianna S. Safronova, *[Nature Communications 15, 5663 (2024)](https://www.nature.com/articles/s41467-024-49241-w)*. 
- **High-Precision Transition Energy Measurements of Neon-like Fe XVII Ions**, Chintan Shah, Moto Togawa, Marc Botz, Jonas Danisch, Joschka J. Goes, Sonja Bernitt, Marleen Maxton, Kai Köbnick, Jen Buck, Jörn Seltmann, Moritz Hoesch, Ming Feng Gu, F. Scott Porter, Thomas Pfeifer, Maurice A. Leutenegger, Charles Cheung, Marianna S. Safronova, José R. Crespo López-Urrutia, *[ApJ 969 52 (2024)](https://iopscience.iop.org/article/10.3847/1538-4357/ad454b)*. 
- **Lifetime-Limited Linewidth Measurements of the 3C and 3D Soft X-ray Transitions in Ni XIX**, Chintan Shah, Steffen Kühn, Sonja Bernitt, René Steinbrügge, Moto Togawa, Lukas Berger, Jens Buck, Moritz Hoesch, Jörn Seltmann, Mikhail G. Kozlov, Sergey G. Porsev, Ming Feng Gu, F. Scott Porter, Thomas Pfeifer, Maurice A. Leutenegger, Charles Cheung, Marianna S. Safronova, and José R. Crespo López-Urrutia, *[Phys. Rev. A 109, 063108 (2024)](https://journals.aps.org/pra/abstract/10.1103/PhysRevA.109.063108)*. 

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## 2023
- **State-Insensitive Trapping of Alkaline-Earth Atoms in a Nanofiber-Based Optical Dipole Trap**, K. Ton, G. Kestler, D. Filin, C. Cheung, P. Schneeweiss, T. Hoinkes, J. Volz, M. S. Safronova, A. Rauschenbeutel, J. T. Barreiro, *[PRX Quantum 4, 040308 (2023)](https://journals.aps.org/prxquantum/abstract/10.1103/PRXQuantum.4.040308)*.
- **Calculations of multipole transitions in Sn II for kilonova analysis**, Andrey I. Bondarev, James Gillanders, Charles Cheung, Marianna S. Safronova, and Stephan Fritzsche, *[Eur. Phys. J. D 77, 126 (2023)](https://link.springer.com/article/10.1140/epjd/s10053-023-00695-5)*. 
- **Optical Telecommunications-Band Clock based on Neutral Titanium Atoms**, Scott Eustice, Dmytro Filin, Jackson Schrott, Sergey Porsev, Charles Cheung, Diego Novoa, Dan M. Stamper-Kurn, Marianna S. Safronova, *[Phys. Rev. A 107, L051102 (2023)](https://journals.aps.org/pra/abstract/10.1103/PhysRevA.107.L051102)*.

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## 2022
- **Calculation of energies and hyperfine-structure constants of <sup>233</sup>U<sup>+</sup> and <sup>233</sup>U**, S. G. Porsev, C. Cheung, and M. S. Safronova, *[Phys. Rev. A 106, 042810 (2022)](https://journals.aps.org/pra/abstract/10.1103/PhysRevA.106.042810)*.
- **New Measurement Resolves Key Astrophysical Fe XVII Oscillator Strength Problem**, Steffen Kühn, Charles Cheung, Natalia S. Oreshkina, René Steinbrügge, Moto Togawa, Sonja Bernitt, Lukas Berger, Jens Buck, Moritz Hoesch, Jörn Seltmann, Florian Trinter, Christoph H. Keitel, Mikhail G. Kozlov, Sergey G. Porsev, Ming Feng Gu, F. Scott Porter, Thomas Pfeifer, Maurice A. Leutenegger, Zoltán Harman, Marianna S. Safronova, José R. Crespo López-Urrutia, and Chintan Shah, *[Phys. Rev. Lett. 129, 245001 (2022)](https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.245001)*. *[Physics Viewpoint: Getting a Clearer View of Iron Emission Lines](https://physics.aps.org/articles/v15/187)*.
- **Laser Spectroscopy of the y<sup>7</sup>P<sup>o</sup><sub>J</sub> states of Cr I**, E. B. Norrgard, D. S. Barker, S. P. Eckel, S. G. Porsev, C. Cheung, M. G. Kozlov, I. I. Tupitsyn, and M. S. Safronova, *[Phys. Rev. A 105, 032812 (2022)](https://journals.aps.org/pra/abstract/10.1103/PhysRevA.105.032812)*.

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## 2021
- **Low-lying energy levels of <sup>229</sup>Th<sup>35+</sup> and the electronic bridge process**, S. G. Porsev, C. Cheung and M. S. Safronova, *[Quantum Sci. Technol. 6, 034014 (2021)](https://iopscience.iop.org/article/10.1088/2058-9565/ac08f1)*.
- **Scalable Codes for Precision Calculations of Properties of Complex Atomic Systems**, C. Cheung, M. S. Safronova, S. G. Porsev, *[Symmetry 13 (4), 621 (2021)](https://www.mdpi.com/2073-8994/13/4/621)*.
- **Observation of an electric quadrupole transition in a negative ion: Experiment and Theory**, C. W. Walter, S. E. Spielman, R. Ponce, N. D. Gibson, J. N. Yukich, C. Cheung, and M. S. Safronova, *[Phys. Rev. Lett. 126, 083001 (2021)](https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.126.083001)*.
- **Predicting quasibound states of negative ions: La<sup>-</sup> as a test case**, M. S. Safronova, C. Cheung, M. G. Kozlov, S. E. Spielman, N. D. Gibson, and C. W. Walter, *[Phys. Rev. 103, 022819 (2021)](https://journals.aps.org/pra/abstract/10.1103/PhysRevA.103.022819)*.
  
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## 2020
- **High-resolution photo-excitation measurements exacerbate the long-standing Fe XVII emission problem**, Steffen Kühn et al., *[Phys. Rev. Lett. 124, 225001 (2020)](https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.124.225001)*. *[Physics Synopsis: Resolving Discrepancies in X-Ray Astronomy](https://physics.aps.org/articles/v13/s69)*.
- **Optical clocks based on the Cf<sup>15+</sup> and Cf<sup>17+</sup> ions**, S. G. Porsev, U. I. Safronova, M. S. Safronova, P. O. Schmidt, A. I. Bondarev, M. G. Kozlov, I. I. Tupitsyn, *[Phys. Rev. A 102, 012802 (2020)](https://journals.aps.org/pra/abstract/10.1103/PhysRevA.102.012802)*.
- **Accurate Prediction of Clock Transitions in a Highly Charged Ion with Complex Electronic Structure**, C. Cheung, M. S. Safronova, S. G. Porsev, M. G. Kozlov, I. I. Tupitsyn, and A. I. Bondarev, *[Phys. Rev. Lett. 124, 163001 (2020)](https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.124.163001)*.

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## 2015
- **CI-MBPT: A package of programs for relativistic atomic calculations based on a method combining configuration interaction and many-body perturbation theory**, M. G. Kozlov, S. G. Porsev, M. S. Safronova, and I. I. Tupitsyn, *[Comput. Phys. Commun. 195, 199 (2015)](http://www.sciencedirect.com/science/article/pii/S001046551500185X)*.