Scintillation efficiency measurement of Na recoils in NaI(Tl) below the DAMA/LIBRA energy threshold

Jingke Xu, Emily Shields, Frank Calaprice, Shawn Westerdale, Francis Froborg, Burkhant Suerfu, Thomas Alexander, Ani Aprahamian, Henning O. Back, Clark Casarella, Xiao Fang, Yogesh K. Gupta, Aldo Ianni, Edward Lamere, W. Hugh Lippincott, Qian Liu, Stephanie Lyons, Kevin Siegl, Mallory Smith, Wanpeng Tan, and Bryant Vande Kolk

Phys. Rev. C 92, 015807 – Published 30 July 2015

Abstract

The dark matter interpretation of the DAMA modulation signal depends on the NaI(Tl) scintillation efficiency of nuclear recoils. Previous measurements for Na recoils have large discrepancies, especially in the DAMA/LIBRA modulation energy region. We report a quenching effect measurement of Na recoils in NaI(Tl) from 3 to $52 {keV}_{nr}$ , covering the whole DAMA/LIBRA energy region for dark matter-Na scattering interpretations. By using a low-energy, pulsed neutron beam, a double time-of-flight technique, and pulse-shape discrimination methods, we obtained the most accurate measurement of this kind for NaI(Tl) to date. The results differ significantly from the DAMA reported values at low energies but fall between the other previous measurements. We present the implications of the new quenching results for the dark matter interpretation of the DAMA modulation signal.

3 More

Received 25 March 2015
Revised 2 June 2015

DOI:https://doi.org/10.1103/PhysRevC.92.015807

Authors & Affiliations

Jingke Xu^1,*, Emily Shields¹, Frank Calaprice¹, Shawn Westerdale¹, Francis Froborg¹, Burkhant Suerfu¹, Thomas Alexander^2,3, Ani Aprahamian⁴, Henning O. Back¹, Clark Casarella⁴, Xiao Fang⁴, Yogesh K. Gupta^4,†, Aldo Ianni⁵, Edward Lamere⁴, W. Hugh Lippincott³, Qian Liu⁴, Stephanie Lyons⁴, Kevin Siegl⁴, Mallory Smith⁴, Wanpeng Tan⁴, and Bryant Vande Kolk⁴

¹Department of Physics, Princeton University, Princeton, New Jersey 08544, USA
²Amherst Center for Fundamental Interactions and Physics Department, Amherst, Massachusetts 01003, USA
³Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA
⁴Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556, USA
⁵INFN Laboratori Nazionali del Gran Sasso, SS 17 bis Km 18_910, 067010 Assergi, Italy

^*Corresponding author: jingkexu@princeton.edu
^†Permanent address: Nuclear Physics Division, BARC, Mumbai 400085, India.

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand

Issue

Vol. 92, Iss. 1 — July 2015

Reuse & Permissions

Access Options

Article Available via CHORUS

Download Accepted Manuscript

Author publication services for translation and copyediting assistance advertisement

Physical Review C

covering nuclear physics