Improved measurement of the head-tail effect in nuclear recoils

D. Dujmic; S. Ahlen; P. Fisher; S. Henderson; A. Kaboth; G. Kohse; R. Lanza; M. Lewandowska; J. Monroe; A. Roccaro; G. Sciolla; N. Skvorodnev; H. Tomita; R. Vanderspek; H. Wellenstein; R. Yamamoto

doi:10.1088/1742-6596/120/4/042030

arXiv · 0801.2687

Improved measurement of the head-tail effect in nuclear recoils

D. Dujmic·S. Ahlen·P. Fisher·S. Henderson·A. Kaboth·G. Kohse·R. Lanza·M. Lewandowska·J. Monroe·A. Roccaro·G. Sciolla·N. Skvorodnev·H. Tomita·R. Vanderspek·H. Wellenstein·R. Yamamoto

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Abstract

We present new results with a prototype detector that is being developed by the DMTPC collaboration for the measurement of the direction tag (head-tail) of dark matter wind. We use neutrons from a Cf-252 source to create low-momentum nuclear recoils in elastic scattering with the residual gas nuclei. The recoil track is imaged in low-pressure time-projection chamber with optical readout. We measure the ionization rate along the recoil trajectory, which allows us to determine the direction tag of the incoming neutrons.

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D. Dujmic, S. Ahlen, P. Fisher, S. Henderson, A. Kaboth, G. Kohse, R. Lanza, M. Lewandowska, J. Monroe, A. Roccaro, G. Sciolla, N. Skvorodnev, H. Tomita, R. Vanderspek, H. Wellenstein, R. Yamamoto. 2008-01-17. Improved measurement of the head-tail effect in nuclear recoils. https://doi.org/10.1088/1742-6596/120/4/042030

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