European Physical Journal C: Particles and Fields (Dec 2022)
Measurements of the ionization efficiency of protons in methane
- L. Balogh,
- C. Beaufort,
- A. Brossard,
- J.-F. Caron,
- M. Chapellier,
- J.-M. Coquillat,
- E. C. Corcoran,
- S. Crawford,
- A. Dastgheibi-Fard,
- Y. Deng,
- K. Dering,
- D. Durnford,
- C. Garrah,
- G. Gerbier,
- I. Giomataris,
- G. Giroux,
- P. Gorel,
- M. Gros,
- P. Gros,
- O. Guillaudin,
- E. W. Hoppe,
- I. Katsioulas,
- F. Kelly,
- P. Knights,
- S. Langrock,
- P. Lautridou,
- I. Manthos,
- R. D. Martin,
- J. Matthews,
- J.-P. Mols,
- J.-F. Muraz,
- T. Neep,
- K. Nikolopoulos,
- P. O’Brien,
- M.-C. Piro,
- D. Santos,
- G. Savvidis,
- I. Savvidis,
- F. A. Vazquez de Sola Fernandez,
- M. Vidal,
- R. Ward,
- M. Zampaolo,
- NEWS-G Collaboration
Affiliations
- L. Balogh
- Department of Mechanical and Materials Engineering, Queen’s University
- C. Beaufort
- LPSC, Université Grenoble-Alpes, CNRS/IN2P3
- A. Brossard
- Department of Physics, Engineering Physics and Astronomy, Queen’s University
- J.-F. Caron
- Department of Mechanical and Materials Engineering, Queen’s University
- M. Chapellier
- Department of Physics, Engineering Physics and Astronomy, Queen’s University
- J.-M. Coquillat
- Department of Physics, Engineering Physics and Astronomy, Queen’s University
- E. C. Corcoran
- Chemistry and Chemical Engineering Department, Royal Military College of Canada
- S. Crawford
- Department of Physics, Engineering Physics and Astronomy, Queen’s University
- A. Dastgheibi-Fard
- LPSC, Université Grenoble-Alpes, CNRS/IN2P3
- Y. Deng
- Department of Physics, University of Alberta
- K. Dering
- Department of Physics, Engineering Physics and Astronomy, Queen’s University
- D. Durnford
- Department of Physics, University of Alberta
- C. Garrah
- Department of Physics, University of Alberta
- G. Gerbier
- Department of Physics, Engineering Physics and Astronomy, Queen’s University
- I. Giomataris
- IRFU, CEA, Université Paris-Saclay
- G. Giroux
- Department of Physics, Engineering Physics and Astronomy, Queen’s University
- P. Gorel
- SNOLAB
- M. Gros
- IRFU, CEA, Université Paris-Saclay
- P. Gros
- Department of Physics, Engineering Physics and Astronomy, Queen’s University
- O. Guillaudin
- LPSC, Université Grenoble-Alpes, CNRS/IN2P3
- E. W. Hoppe
- Pacific Northwest National Laboratory
- I. Katsioulas
- School of Physics and Astronomy, University of Birmingham
- F. Kelly
- Chemistry and Chemical Engineering Department, Royal Military College of Canada
- P. Knights
- School of Physics and Astronomy, University of Birmingham
- S. Langrock
- SNOLAB
- P. Lautridou
- SUBATECH, IMT-Atlantique/CNRS-IN2P3/Nantes University
- I. Manthos
- School of Physics and Astronomy, University of Birmingham
- R. D. Martin
- Department of Physics, Engineering Physics and Astronomy, Queen’s University
- J. Matthews
- School of Physics and Astronomy, University of Birmingham
- J.-P. Mols
- IRFU, CEA, Université Paris-Saclay
- J.-F. Muraz
- LPSC, Université Grenoble-Alpes, CNRS/IN2P3
- T. Neep
- School of Physics and Astronomy, University of Birmingham
- K. Nikolopoulos
- School of Physics and Astronomy, University of Birmingham
- P. O’Brien
- Department of Physics, University of Alberta
- M.-C. Piro
- Department of Physics, University of Alberta
- D. Santos
- LPSC, Université Grenoble-Alpes, CNRS/IN2P3
- G. Savvidis
- Department of Physics, Engineering Physics and Astronomy, Queen’s University
- I. Savvidis
- Aristotle University of Thessaloniki
- F. A. Vazquez de Sola Fernandez
- SUBATECH, IMT-Atlantique/CNRS-IN2P3/Nantes University
- M. Vidal
- Department of Physics, Engineering Physics and Astronomy, Queen’s University
- R. Ward
- School of Physics and Astronomy, University of Birmingham
- M. Zampaolo
- LPSC, Université Grenoble-Alpes, CNRS/IN2P3
- NEWS-G Collaboration
- DOI
- https://doi.org/10.1140/epjc/s10052-022-11063-9
- Journal volume & issue
-
Vol. 82,
no. 12
pp. 1 – 10
Abstract
Abstract The amount of energy released by a nuclear recoil ionizing the atoms of the active volume of detection appears “quenched” compared to an electron of the same kinetic energy. This different behavior in ionization between electrons and nuclei is described by the Ionization Quenching Factor (IQF) and it plays a crucial role in direct dark matter searches. For low kinetic energies (below $$50~\textrm{keV}$$ 50 keV ), IQF measurements deviate significantly from common models used for theoretical predictions and simulations. We report measurements of the IQF for proton, an appropriate target for searches of Dark Matter candidates with a mass of approximately $$1~\textrm{GeV}$$ 1 GeV , with kinetic energies in between $$2~\textrm{keV}$$ 2 keV and $$13~\textrm{keV}$$ 13 keV in $$100~\textrm{mbar}$$ 100 mbar of methane. We used the Comimac facility in order to produce the motion of nuclei and electrons of controlled kinetic energy in the active volume, and a NEWS-G SPC to measure the deposited energy. The Comimac electrons are used as a reference to calibrate the detector with 7 energy points. A detailed study of systematic effects led to the final results well fitted by $$\textrm{IQF}~(E_K)= E_K^\alpha ~/~(\beta + E_K^\alpha )$$ IQF ( E K ) = E K α / ( β + E K α ) with $$\alpha = 0.70\pm 0.08$$ α = 0.70 ± 0.08 and $$\beta = 1.32\pm 0.17$$ β = 1.32 ± 0.17 . In agreement with some previous works in other gas mixtures, we measured less ionization energy than predicted from SRIM simulations, the difference reaching $$33\%$$ 33 % at $$2~\textrm{keV}$$ 2 keV .
