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Title: Background Studies for the pn-CCD Detector of CAST

Abstract

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.

Authors:
; ; ; ; ; ; ; ;  [1];  [2];  [3];  [2];  [4];  [5];  [3];  [3];  [2];  [3]
  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. (Germany)
  4. Technische Universitaet Darmstadt, IKP, Schlossgartenstrasse 9, 64289 Darmstadt (Germany)
  5. Max-Planck-Institut fuer extraterrestrische Physik, Giessenbachstrasse, D-85748 Garching (Germany)
Publication Date:
OSTI Identifier:
21055020
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 897; Journal 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)
Country of Publication:
United States
Language:
English
Subject:
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

Citation Formats

Rodriguez, A., Beltran, B., Cebrian, S., Gomez, H., Irastorza, I. G., Luzon, G., Morales, J., Ruz, J., Villar, J. A., Hartmann, R., PNSensor GmbH, Roemerstrasse 28, D-80803 Muenchen,, Kotthaus, R., Klose, C., Kuster, M., Technische Universitaet Darmstadt, IKP, Schlossgartenstrasse 9, 64289 Darmstadt, Gesellschaft fuer Schwerionenforschung, GSI-Darmstadt, Plasmaphysik, Planckstr, 1, 64291 Darmstadt, Strueder, L., and Max-Planck-Institut fuer extraterrestrische Physik, Giessenbachstrasse, D-85748 Garching. Background Studies for the pn-CCD Detector of CAST. United States: N. p., 2007. Web. doi:10.1063/1.2722082.
Rodriguez, A., Beltran, B., Cebrian, S., Gomez, H., Irastorza, I. G., Luzon, G., Morales, J., Ruz, J., Villar, J. A., Hartmann, R., PNSensor GmbH, Roemerstrasse 28, D-80803 Muenchen,, Kotthaus, R., Klose, C., Kuster, M., Technische Universitaet Darmstadt, IKP, Schlossgartenstrasse 9, 64289 Darmstadt, Gesellschaft fuer Schwerionenforschung, GSI-Darmstadt, Plasmaphysik, Planckstr, 1, 64291 Darmstadt, Strueder, L., & Max-Planck-Institut fuer extraterrestrische Physik, Giessenbachstrasse, D-85748 Garching. Background Studies for the pn-CCD Detector of CAST. United States. doi:10.1063/1.2722082.
Rodriguez, A., Beltran, B., Cebrian, S., Gomez, H., Irastorza, I. G., Luzon, G., Morales, J., Ruz, J., Villar, J. A., Hartmann, R., PNSensor GmbH, Roemerstrasse 28, D-80803 Muenchen,, Kotthaus, R., Klose, C., Kuster, M., Technische Universitaet Darmstadt, IKP, Schlossgartenstrasse 9, 64289 Darmstadt, Gesellschaft fuer Schwerionenforschung, GSI-Darmstadt, Plasmaphysik, Planckstr, 1, 64291 Darmstadt, Strueder, L., and Max-Planck-Institut fuer extraterrestrische Physik, Giessenbachstrasse, D-85748 Garching. Wed . "Background Studies for the pn-CCD Detector of CAST". United States. doi:10.1063/1.2722082.
@article{osti_21055020,
title = {Background Studies for the pn-CCD Detector of CAST},
author = {Rodriguez, A. and Beltran, B. and Cebrian, S. and Gomez, H. and Irastorza, I. G. and Luzon, G. and Morales, J. and Ruz, J. and Villar, J. A. and Hartmann, R. and PNSensor GmbH, Roemerstrasse 28, D-80803 Muenchen, and Kotthaus, R. and Klose, C. and Kuster, M. and Technische Universitaet Darmstadt, IKP, Schlossgartenstrasse 9, 64289 Darmstadt and Gesellschaft fuer Schwerionenforschung, GSI-Darmstadt, Plasmaphysik, Planckstr, 1, 64291 Darmstadt and Strueder, L. and Max-Planck-Institut fuer extraterrestrische Physik, Giessenbachstrasse, D-85748 Garching},
abstractNote = {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.},
doi = {10.1063/1.2722082},
journal = {AIP Conference Proceedings},
number = 1,
volume = 897,
place = {United States},
year = {Wed Mar 28 00:00:00 EDT 2007},
month = {Wed Mar 28 00:00:00 EDT 2007}
}
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