Neutron energy spectrum measurement of the Back-n white neutron source at CSNS


China Spallation Neutron Source (CSNS) has been built and commissioned successfully in 2018 which is implemented by impinging 1.6 GeV protons onto a tungsten target with 25 Hz repetition frequency. An associated white neutron beam line exploiting the back-streaming neutrons, named Back-n, with a flight path of 55 m in endstation 1 (#ES1) and 76 m in endstation 2 (#ES2) was built mainly for nuclear data measurements. The Back-n beam line started running since the beginning of 2018 and the neutron energy spectrum was measured at the very beginning since it is an essential information for feasibility study and analysis of any measurement. In this paper, the measurement of the neutron energy spectrum of Back-n #ES2 is reported. The first result of the neutron flux from 1 eV to 100 MeV measured by a fission chamber based on the 235U(n, f) reaction is presented. The total neutron flux normalized to the proton beam power of 100 kW is \( 7.03 \times 10^{6}\) neutrons/cm2/s. The results show a good agreement with that of the Monte Carlo simulation as well.

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  • 30 August 2019

    In the original article, there were some errors in the list of authors and affiliations. Their correct version is given in this erratum.


  1. 1

    S.X. Fang et al., J. Korean Phys. Soc. 48, 697 (2006)

    Google Scholar 

  2. 2

    J. Wei et al., Nucl. Instrum. Methods A 600, 10 (2009)

    ADS  Article  Google Scholar 

  3. 3

    H. Chen et al., Nat. Mater. 15, 689 (2016)

    ADS  Article  Google Scholar 

  4. 4

    F.W. Wang et al., Sci. Chin. Phys. Mech. Astron. 56, 2410 (2013)

    ADS  Article  Google Scholar 

  5. 5

    Q. An et al., J. Instrum. 12, 07022 (2017)

    Google Scholar 

  6. 6

    J.Y. Tang et al., Chin. Phys. C 34, 121 (2010)

    ADS  Article  Google Scholar 

  7. 7

    H.T. Jing et al., Nucl. Instrum. Methods A 621, 91 (2010)

    ADS  Article  Google Scholar 

  8. 8

    J.Y. Tang et al., At. Energy Sci. Technol. 47, 1089 (2013) (in Chinese)

    Google Scholar 

  9. 9

    H.T. Jing et al., Chin. Phys. C 37, 117002 (2013)

    ADS  Article  Google Scholar 

  10. 10

    Q. Wang et al., Rev. Sci. Instrum. 89, 013511 (2018)

    ADS  Article  Google Scholar 

  11. 11

    D.A. Brown et al., Nucl. Data Sheets 148, 1 (2018)

    ADS  Article  Google Scholar 

  12. 12

    P.H. White, Nucl. Instrum. Methods 79, 1 (1970)

    ADS  Article  Google Scholar 

  13. 13

    G.W. Carlson, Nucl. Instrum. Methods 119, 97 (1974)

    ADS  Article  Google Scholar 

  14. 14

    Fasso, Fluka: A multi-particle transport code, Technical Report CERN-2005-10, INFN/TC 05/11, SLAC-R-73 (2005)

  15. 15

    Y. Watanabe et al., J. Korean Phys. Soc. 59, 1040 (2011)

    ADS  Article  Google Scholar 

  16. 16

  17. 17

    A.D. Carlson et al., Nucl. Data Sheets 110, 3215 (2009)

    ADS  Article  Google Scholar 

  18. 18

    G. Lorusso et al., Nucl. Instrum. Methods A 532, 622 (2004)

    ADS  Article  Google Scholar 

  19. 19

    M. Sabate et al., Eur. Phys. J. A 53, 210 (2017)

    ADS  Article  Google Scholar 

  20. 20

    J. Lerendegu et al., Eur. Phys. J. A 52, 100 (2016)

    ADS  Article  Google Scholar 

  21. 21

    L.Y. Zhang, Study and physical design of white neutron beamlines at CSNS, PhD Thesis, University of Science and Technology of China, 2018 (in Chinese)

  22. 22

    K. Shibata et al., J. Nucl. Sci. Technol. 48, 1 (2011)

    Article  Google Scholar 

  23. 23

  24. 24

    Z.G. Ge et al., J. Korean Phys. Soc. 59, 1052 (2011)

    ADS  Article  Google Scholar 

Download references

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Correspondence to Jie Bao.

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Data Availability Statement

This manuscript has no associated data or the data will not be deposited. [Authors’ comment: All data generated during this study are contained in this published article.]

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Communicated by S. Bhattacharya

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Chen, Y., Luan, G., Bao, J. et al. Neutron energy spectrum measurement of the Back-n white neutron source at CSNS. Eur. Phys. J. A 55, 115 (2019).

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