First underground results with NEWAGE-0.3a direction-sensitive dark matter detector

TL;DR

This paper reports the first underground results using the NEWAGE-0.3a detector, a gaseous micro-TPC, achieving improved limits on spin-dependent WIMP-proton interactions with a novel direction-sensitive approach.

Contribution

It presents the first underground dark matter search results with the NEWAGE-0.3a detector, demonstrating a new record in WIMP-proton cross section limits using a direction-sensitive method.

Findings

Achieved a WIMP-proton cross section limit of 5400 pb at 150 GeV/c2.

Identified ambient gamma-rays and internal radioactive contaminants as main backgrounds.

Provided the first underground directional dark matter search results with this detector.

Abstract

A direction-sensitive dark matter search experiment at Kamioka underground laboratory with the NEWAGE-0.3a detector was performed. The NEWAGE- 0.3a detector is a gaseous micro-time-projection chamber filled with CF4 gas at 152 Torr. The fiducial volume and target mass are 20*25*31 cm3 and 0.0115 kg, respectively. With an exposure of 0.524 kgdays, improved spin-dependent weakly interacting massive particle (WIMP)-proton cross section limits by a direction-sensitive method were achieved including a new record of 5400 pb for 150 GeV/c2 WIMPs. We studied the remaining background and found that ambient gamma-rays contributed about one-fifth of the remaining background and radioactive contaminants inside the gas chamber contributed the rest.