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Radiation-tolerant polarized solid target

K. Tateishi1,2,*, Y. Saito1, D. Takahashi3, K. Sekiguchi1,3,4, K. Aradono5, K. Hirasawa5, Y. Maeda6, Y. Nagao5, H. Nishibata5 et al.

S. Otsuka2,7, H. Sakai1, H. Sugahara3, K. Suzuki3, T. Uesaka1,2,7, T. Wakasa5, and A. Watanabe1

  • *Contact author: kenichiro.tateishi@riken.jp
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Phys. Rev. Research 8, L022005 – Published 3 April, 2026

DOI: https://doi.org/10.1103/yj5b-yk6n

Abstract

Polarized targets evolved into indispensable tools in particle and nuclear physics. However, the polarized solid target is degraded by high-intensity beam irradiation, known as radiation damage due to target heating and radical generation. We demonstrated a radiation-tolerant polarized solid target operating at room temperature. An annealing allows the spontaneous repair of the damage by reducing unwanted radicals. Using a single crystal of p-terphenyl doped with 0.01 mol% pentacene-d14, dynamic nuclear polarization using photoexcited triplet electrons was applied to proton spins at room temperature and in 0.39 T. For the proof of concept, a deuteron beam with an energy of 135 MeV/u and intensities of 107–109 counts per second (cps) was irradiated. The proton polarization was determined to be 3.0%±0.2%(stat.)±0.1%(sys.) from a scattering asymmetry. The polarization was almost not attenuated up to 109 cps, but the target crystal was yellowed. The visible-light absorption spectroscopy suggested irreversible radiation damage due to missing protons by the knockout reaction. The room-temperature polarized solid target allows impractical experiments with the conventional target system, leading to a next-generation spin-dependent accelerator science.

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References (31)

  1. V. Andrieux, et al., The large COMPASS polarized solid ammonia target for Drell-Yan measurements with a pion beam, Nucl. Instrum. Methods Phys. Res., Sect. A 1025, 166069 (2022).
  2. T. Uesaka, et al., Analyzing power for proton elastic scattering from the neutron-rich He6 nucleus, Phys. Rev. C 82, 021602 (2010).
  3. A. Watanabe, et al., Spin correlation coefficient for proton-He3 elastic scattering at 100 MeV, Phys. Rev. C 106, 054002 (2022).
  4. J. Eills, et al., Spin hyperpolarization in modern magnetic resonance, Chem. Rev. 123, 1417 (2023).
  5. A. Abragam and M. Goldman, Nuclear Magnetism: Order and Disorder (Clarendon, Oxford/Oxford University Press, New York, 1982).
  6. D. G. Crabb and W. Meyer, Solid polarized targets for nuclear and particle physics experiments, Annu. Rev. Nucl. Part. Sci. 47, 67 (1997).
  7. A. Thomas, et al., Behaviour of polarized ammonia in an intense electron beam, Nucl. Instrum. Methods Phys. Res. Sect. A 356, 5 (1995).
  8. T. J. Liu, T. D. Averett, D. G. Crabb, D. B. Day, J. S. McCarthy, and O. A. Rondon, Depolarization of dynamically polarized solid targets due to beam heating effects, Nucl. Instrum. Methods Phys. Res. Sect. A 405, 1 (1998).
  9. W. Meyer, Ammonia as a polarized solid target material—A review, Nucl. Instrum. Methods Phys. Res. Sect. A 526, 12 (2004).
  10. S. Goertz, A. Berlin, M. Bornstein, H. Dutz, J. Herick, S. Reeve, G. Rieicherz, and S. Runkel, Polarized solid target material developments at Bonn and Bochum, PoS PSTP2015, 009 (2015).
  11. P. M. McKee, Observations of radiation damage and recovery in ammonia targets, Nucl. Instrum. Methods Phys. Res. Sect. A 526, 60 (2004).
  12. A. Capozzi, T. Cheng, G. Boero, C. Roussel, and A. Comment, Thermal annihilation of photo-induced radicals following dynamic nuclear polarization to produce transportable frozen hyperpolarized C13-substrates, Nat. Commun. 8, 15757 (2017).
  13. A. Henstra, T. S. Lin, J. Schmidt, and W. T. Wenckebach, High dynamic nuclear polarization at room temperature, Chem. Phys. Lett. 165, 6 (1990).
  14. K. Takeda, Triplet State Dynamic Nuclear Polarization (VDM, Saarbrucken, Germany, 2009).
  15. T. Hamachi and N. Yanai, Recent developments in materials and applications of triplet dynamic nuclear polarization, Prog. Nucl. Magn. Reson. Spectrosc. 142-143, 55 (2024).
  16. J. L. Ong, D. J. Sloop, and T. S. Lin, Deuteration effect on the spin dynamics of the photo-excited triplet state of pentacene in p-terphenyl crystals, Chem. Phys. Lett. 241, 540 (1995).
  17. Y. Quan, B. Brandt, J. Kohlbrecher, W. T. Wenckebach, and P. Hautle, A transportable neutron spin filter, Nucl. Instrum. Methods Phys. Res. Sect. A 921, 22 (2019).
  18. P. Hautle and W. T. Wenckebach, Creating high, portable proton polarization with photo-excited triplet DNP, J. Magn. Reson. Open 20, 100159 (2024).
  19. S. Takada, K. Tateishi, Y. Wakabayashi, Y. Ikeda, T. Yoshioka, Y. Otake, and T. Uesaka, Polarized proton spin filter for epithermal neutrons based on dynamic nuclear polarization using photo-excited triplet electron spins, Prog. Theor. Exp. Phys. 2020, 123G01 (2020).
  20. A. Watanabe, et al., Development of a polarized proton solid target for measuring the spin correlation coefficient of deuteron-proton scattering and analysis of radiation damage, Nucl. Instrum. Methods Phys. Res. Sect. A 1078, 170562 (2025).
  21. K. Tateishi, M. Negoro, S. Nishida, A. Kagawa, Y. Morita, and M. Kitagawa, Room temperature hyperpolarization of nuclear spins in bulk, Proc. Natl. Acad. Sci. USA 111, 7527 (2014).
  22. A. Henstra and W. T. Wenckebach, Dynamic nuclear via the integrated solid effect I: Theory, Mol. Phys. 112, 1761 (2014).
  23. K. Takeda, OPENCORE NMR: Open-source core modules for implementing an integrated FPGA-based NMR spectrometer, J. Magn. Reson. 192, 218 (2008).
  24. K. Ermisch, et al., Search for three-nucleon force effects in analyzing powers for p⃗d elastic scattering, Phys. Rev. Lett. 86, 5862 (2001).
  25. B. v. Przewoski, F. Rathmann, T. Rinckel, S. K. Saha, B. Schwartz, P. Thörngren-Engblom, A. Wellinghausen, T. J. Whitaker, and T. Wise, Analyzing powers and spin correlation coefficients for p+d elastic scattering at 135 and 200 MeV, Phys. Rev. C 74, 064003 (2006).
  26. Y. Saito, Developments toward the measurement of spin correlation coefficients for d−p elastic scattering, Ph.D. thesis, Tohoku University, 2025.
  27. K. Sekiguchi, et al., Resolving the discrepancy of 135 MeV pd elastic scattering cross sections and relativistic effects, Phys. Rev. Lett. 95, 162301 (2005).
  28. K. Tateishi, S. Otsuka, A. Yamaji, S. Kurosawa, and T. Uesaka, H1 polarization above 60% at room temperature by triplet dynamic nuclear polarization, Chem. Phys. Lett. 885, 142606 (2026).
  29. F. Cataldo, S. Iglesias-Groth, and A. Manchado, Electronic absorption spectroscopy of polycyclic aromatic hydrocarbons (PAHs) radical cations generated in oleum: A superacid medium, Spectrochim. Acta, Part A 77, 998 (2010).
  30. K. Hebeler, Three-nucleon forces: Implementation and applications to atomic nuclei and dense matter, Phys. Rep. 890, 1 (2021).
  31. J. Carlson, S. Gandolfi, F. Pederiva, S. C. Pieper, R. Schiavilla, K. E. Schmidt, and R. B. Wiringa, Quantum Monte Carlo methods for nuclear physics, Rev. Mod. Phys. 87, 1067 (2015).

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Phys. Rev. Research 8, L022005– Published 3 April, 2026
  • Received 7 August 2025
  • Accepted 20 February 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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