Background Studies for the pn-CCD Detector of CAST

Journal Article · Wed Mar 28 00:00:00 EDT 2007 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.2722082· OSTI ID:21055020

Rodriguez, A; Beltran, B; Cebrian, S; Gomez, H; Irastorza, I G; Luzon, G; Morales, J; Ruz, J; Villar, J A ^[1]; Hartmann, R ^[2]; Kotthaus, R ^[2]; Klose, C ^[3]; Kuster, M ^[4]; Strueder, L ^[2]

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1. Laboratorio de Fisica Nuclear y de Altas Energias, Universidad de Zaragoza, 50009 Zaragoza (Spain)
2. MPI Halbleiterlabor Otto-Hahn-Ring 6, 81739 Munich (Germany)
3. Technische Universitaet Darmstadt, IKP, Schlossgartenstrasse 9, 64289 Darmstadt (Germany)
4. Max-Planck-Institut fuer extraterrestrische Physik, Giessenbachstrasse, D-85748 Garching (Germany)

The CERN Axion Solar Telescope (CAST) experiment searches for axions from the Sun converted into photons with energies up to around 10 keV via the inverse Primakoff effect in the high magnetic field of a superconducting Large Hadron Collider (LHC) prototype magnet. A backside illuminated pn-CCD detector in conjunction with an X-ray mirror optics is one of the three detectors used in CAST to register the expected photon signal. Since this signal is very rare a detailed study of the detector background has been undertaken with the aim to understand and further reduce the background level of the detector. The analysis is based on measured data taken during the data taking period of 2003 and 2004 of CAST and on Monte Carlo simulations of background with different origin. The background study performed for this detector show that the level of background (8.00{+-}0.07)x10-5 counts cm-2 s-1 keV-1 between 1 and 7 keV is dominated by the external gamma background due to natural activities at the experimental site, while radioactive impurities in the detector itself and cosmic neutrons contribute with a smaller fraction.

• OSTI ID: 21055020
• Journal Information: AIP Conference Proceedings, Vol. 897, Issue 1; Conference: LRT 2006: Topical workshop on low radioactivity techniques, Aussois (France), 1-4 Oct 2006; Other Information: DOI: 10.1063/1.2722082; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
AXIONS
CERN
CERN LHC
CHARGE-COUPLED DEVICES
COMPUTERIZED SIMULATION
COSMIC NEUTRONS
KEV RANGE
MAGNETIC FIELDS
MONTE CARLO METHOD
NATURAL RADIOACTIVITY
PARTICLE IDENTIFICATION
PHOTONS
PRIMAKOFF EFFECT
SUN
SUPERCONDUCTING MAGNETS
TELESCOPE COUNTERS
X RADIATION