Surface purity control during XMASS detector refurbishment

The XMASS project aims at detecting dark matter, pp and 7Be solar neutrinos, and neutrino less double beta decay using large volume of pure liquid xenon. The first physics target of the XMASS project is to detect dark matter with 835 kg liquid xenon. After the commissioning runs, XMASS detector was refurbished to minimize the background contribution mainly from PMT sealing material and we restarted data taking in November 2013. We report how we control surface purity, especially how we prevent radon daughter accumulation on the detector coppersurface, during XMASS detector refurbishment. The result and future plan of XMASS are also reported.

Liquid surfaces
Dark matter
Liquid noble gases
Copper
Double beta decay
xenon: liquid
copper: surface
dark matter: detector
photomultiplier
background

References(4)

Figures(0)

[1]

Low-energy solar neutrino detection by using liquid xenon

XENON

Collaboration

•

Y. Suzuki
(
- Kamioka Observ.
)

for the collaboration.

e-Print:
- hep-ph/0008296
•
DOI:
- 10.1142/9789812778000_0009

[2]

XMASS detector

K. Abe
(
- Kamioka Observ. and
- Tokyo U., IPMU and
- Tokyo U., ICRR
)
,
K. Hieda
(
- Kamioka Observ. and
- Tokyo U., ICRR
)
,
K. Hiraide
(
- Kamioka Observ. and
- Tokyo U., ICRR and
- Tokyo U., IPMU
)
,
S. Hirano
(
- Kamioka Observ. and
- Tokyo U., ICRR
)
,
Y. Kishimoto
(
- Kamioka Observ. and
- Tokyo U., ICRR and
- Tokyo U., IPMU
)

et al.

- Nucl.Instrum.Meth.A 716 (2013) 78-85
•
e-Print:
- 1301.2815
•
DOI:
- 10.1016/j.nima.2013.03.059

[3]

Y. Takeuchi

- Nucl.Instrum.Meth.A 42 (1999) 334
•
DOI:
- 10.1016/S0168-9002(98)01204-2