Simulation and measurement of the suppression of radon induced background in the KATRIN experiment - INSPIRE

DataBETA

Simulation and measurement of the suppression of radon induced background in the KATRIN experiment

J. Wolf
(
- KIT, Karlsruhe, EKP
)
,
F. Harms
(
- KIT, Karlsruhe, IKP
)

Jan 3, 2018

Part of Proceedings, 6th Topical Workshop on Low Radioactivity Techniques (LRT 2017) : Seoul, Korea, May 24-26, 2017

Published in:

AIP Conf.Proc. 1921 (2018) 1, 060001

Contribution to:

- LRT 2017

Published: Jan 3, 2018

DOI:

10.1063/1.5018997

reference search3 citations

Citations per year

Abstract: (AIP)

Short-lived radon isotopes, such as 219Rn or 220Rn, are a serious source of background for the measurement of the neu-trino mass with the KATRIN experiment. Most of the radon emanates from the main vacuum pumps of the KATRIN Main Spec-trometer, which consist of 2000 m of Non-Evaporable Getter (NEG) strips. This paper describes a method to suppress the radon rate with liquid-nitrogen-cooled baffles in front of the NEG-pumps in the ultra-high vacuum chamber and compares simulations with measured data. The effectiveness of the method depends both on the half-life of the radon isotopes, and on the temperature of the cryogenic baffles, which affects their sojourn time on the cold surface. The measurements with the Main Spectrometer showed that the radon suppression with cold baffles works sufficiently well, so that the remaining background is no longer dominated by radon decays.

radon: decay
radon: nuclide
background: induced
KATRIN
background: suppression
vacuum system
spectrometer
background: radioactivity
numerical calculations

References(18)

Figures(0)

[1]

KATRIN design report 2004

KATRIN

Collaboration

•

J. Angrik

et al.

[2]

Background due to stored electrons following nuclear decays in the KATRIN spectrometers and its impact on the neutrino mass sensitivity

S. Mertens
(
- KIT, Karlsruhe
)
,
G. Drexlin
(
- KIT, Karlsruhe
)
,
F.M. Fränkle
(
- KIT, Karlsruhe and
- North Carolina U.
)
,
D. Furse
(
- MIT
)
,
F. Glück
(
- KIT, Karlsruhe and
- Budapest, RMKI
)

et al.

- Astropart.Phys. 41 (2013) 52-62
•
e-Print:
- 1204.6213
•
DOI:
- 10.1016/j.astropartphys.2012.10.005

[3]

A METHOD FOR MEASURING THE ANTI-ELECTRON-NEUTRINO REST MASS

V.M. Lobashev
(
- Moscow, INR
)
,
P.E. Spivak
(
- Kurchatov Inst., Moscow
)

- Nucl.Instrum.Meth.A 240 (1985) 305-310,
- Nucl. Instrum. Methods A240 ( 1985) 305-310
•
DOI:
- 10.1016/0168-9002(85)90640-0

[4]

A solenoid retarding spectrometer with high resolution and transmission for keV electrons

et al.

- Nucl.Instrum.Meth.B 63 (1992) 3, 345-358
•
DOI:
- 10.1016/0168-583X(92)95119-C

[5]

Validation of a model for Radon-induced background processes in electrostatic spectrometers

N. Wandkowsky
(
- KIT, Karlsruhe
)
,
G. Drexlin
(
- KIT, Karlsruhe
)
,
F.M. Fränkle
(
- KIT, Karlsruhe and
- North Carolina U.
)
,
F. Glück
(
- KIT, Karlsruhe and
- Budapest, RMKI
)
,
S. Groh
(
- KIT, Karlsruhe
)

et al.

- J.Phys.G 40 (2013) 085102
•
e-Print:
- 1304.1379
•
DOI:
- 10.1088/0954-3899/40/8/085102

[6]

Characterization and Minimization of Background Processes in the KATRIN Main Spectrometer, PhD-thesis, KIT

F. Harms

[7]

Commissioning of the vacuum system of the KATRIN Main Spectrometer

KATRIN

Collaboration

•

M. Arenz
(
- Bonn U., HISKP
)

et al.

- JINST 11 (2016) 04, P04011
•
e-Print:
- 1603.01014
•
DOI:
- 10.1088/1748-0221/11/04/P04011

[8]

KATRIN NEG pumping concept investigation

X. Luo
(
- Karlsruhe, Forschungszentrum and
- Karlsruhe U., EKP
)
,
L. Bornschein
(
- Karlsruhe, Forschungszentrum and
- Karlsruhe U., EKP
)
,
C. Day
(
- Karlsruhe, Forschungszentrum and
- Karlsruhe U., EKP
)
,
J. Wolf
(
- Karlsruhe, Forschungszentrum and
- Karlsruhe U., EKP
)

- Vacuum 81 (2007) 777-781
•
DOI:
- 10.1016/j.vacuum.2005.11.053

[9]

Radon induced background processes in the KATRIN pre-spectrometer

F.M. Frankle
(
- KIT, Karlsruhe and
- North Carolina U. and
- TUNL, Durham
)
,
L. Bornschein
(
- KIT, Karlsruhe and
- North Carolina U. and
- TUNL, Durham
)
,
G. Drexlin
(
- KIT, Karlsruhe and
- North Carolina U. and
- TUNL, Durham
)
,
F. Gluck
(
- KIT, Karlsruhe and
- North Carolina U. and
- TUNL, Durham
)
,
S. Gorhardt
(
- KIT, Karlsruhe and
- North Carolina U. and
- TUNL, Durham
)

et al.

- Astropart.Phys. 35 (2011) 128-134
•
e-Print:
- 1103.6238
•
DOI:
- 10.1016/j.astropartphys.2011.06.009

[10]

Background Reduction Methods and Vacuum Technology at the KATRIN Spectrometers, PhD-thesis, KIT

S. Görhardt

[11]

Handbook of Vacuum Technology

K. Jousten editor

[12]

R. Eichler
,
M. Schädel

- J.Phys.Chem.B 106 (2002) 5413-5420
•
DOI:
- 10.1021/jp015553q

[13]

A. Junod

- J.Phys.Condens.Matter 1 (1989) 8021-8034

[14]

J. Phys. Chem. A

B. Eichler
,
H.P. Zimmermann
,
H.W. Gäggeler

•
DOI:
- 10.1021/jp9932158

[15]

R. Kersevan
,
J.-L. Pons

- J.Vac.Sci.Tech.A 27 (2009) 1017
•
DOI:
- 10.1116/1.3153280

[16]

MOLFLOW+, molecular flow TPMC simulation code

[17]

Molflow+ User Guide

M. Ady
,
R. Kersevan

[18]

Calculations and TPMC simulations of the reduction of radioactive decays of a noble gas by cryo-panels

et al.

- Vacuum 138 (2017) 165-172
•
DOI:
- 10.1016/j.vacuum.2016.12.013