For further information, please contact: [email protected]
1
For further information, please contact: [email protected] Purpose of Calibration: - provide performance verification of the GBM detectors. - provide benchmark data to compare with calculated detector response data. - provide accurate, well-characterized data for subsequent scientific analysis. The GBM-NaI(Tl) Detectors (12 x): The GBM-BGO Detectors (2 x): The calibration of the GLAST Burst Monitor NaI- and BGO-detectors by Andreas von Kienlin 1 , Julia Wagner 1 , Helmut Steinle 1 , Narayana Bhat 2 , Michael S. Briggs 2 , Roland Diehl 1 , Gerald J. Fishman 3 , Jochen Greiner 1 , R. Marc Kippen 4 , Chryssa Kouveliotou 5 , Giselher G. Lichti 1 , Charles A. Meegan 3 , William S. Paciesas 2 , Robert D. Preece 2 , Robert B. Wilson 2 GLAST Burst Monitor 0 5000 10000 15000 20000 25000 30000 -0.1 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 T ra nsm ission P hoton E ne rg y [e V ] B e:200 m 20 M ilT e tra tex S ilicon e P ad:700 m N aI:S um X-ray Transmission of the NaI Entrance Window: The installation of an 0.7 mm thick silicon pad between the Beryllium entrance window and the crystal was necessary so that the brittle NaI crystal is able to survive the environmental conditions during launch. This additional silicon layer caused unfortunately a degradation of the transmissivity at low energies (at 10 keV ~ 30%). [1] Max-Planck-Institut für extraterrestrische Physik (MPE); [2] University of Alabama (UAH); [3] NASA/Marshall Space-Flight Center (MSFC), [4] Los Alamos National Laboratory (LANL), [5] USRA z y 118 138 158 187.5 40° 45° HV x y 133.5 154 The Calibration Setup: - allowes the acquisition of spectra at different angles of incidence. - high accuracy due to laser adjustment. List of Calibration Sources: Calibration Results: The figures below summarize the main measurements performed with the flight detectors. All detectors of the same type showed nearly the same performance and all fulfilled the specified requirements. 0 500 1000 1500 2000 2500 3000 3500 0 200 400 600 800 1000 0 500 1000 1500 2000 2500 3000 3500 -16 -12 -8 -4 0 4 G B M -N aIdetector E n e rg y [ke V ] C hannelN um ber C hannel-E nergy R e lation (p arab ola) R esidual[keV ] C hannelN um ber 0 100 200 300 400 500 600 700 800 900 -1 0 -5 0 5 10 15 20 25 30 35 Linearity of the C hannel-E nergy R elation - deviation from parabolic relation G BM -N aIdetector E n e rg y [% ] E nergy [keV ] 0 100 200 300 400 500 600 0 1000 2000 3000 4000 5000 0 100 200 300 400 500 600 -5 0 5 10 15 C hannel E nergy [keV ] C hannel-E nergy R elation (line) G B M -B G O d etecto r R e sid uals [keV ] C hannel 0 1000 2000 3000 4000 5000 -3 -2 -1 0 1 L in earity of the C hannel-E nergy R elation - deviation from linear relation G B M -N aIdetector E n e rg y [% ] E nergy [keV ] 0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 0 5 10 15 20 25 30 35 40 45 R e lative E nergy R esolu tion (F W HM) A rrow s:R equirem ents G B M -B G O d etecto r FW H M [ E /E in % ] E nergy [keV ] 0 100 200 300 400 500 600 700 800 900 1000 5 10 15 20 25 30 35 40 45 50 R ea ltive E ne rg y R eso lu tio n (F W HM) A rrow s: R e quirem e nts G B M -N aIdetector FW H M [ E /E in % ] E nergy [keV ] 10 100 1000 1 10 100 1000 G B M -N aIdetector E ffe ctive A re a [cm 2 ] E n ergy [ke V ] -10 0 -5 0 0 50 100 150 200 250 300 0 1x10 5 2x10 5 3x10 5 4x10 5 5x10 5 6x10 5 R elative R esponse as a F unction of the O ff-A xis A ngle G B M -N aIdetector Location of P M T + FE E 3 2 .8 9 ke V Integ ra ted C ounts ofP hotopeak S ource A n gle [d e g] 661.66 keV -2 00 -1 50 -100 -50 0 50 100 150 200 3x10 5 4x10 5 5x10 5 6x10 5 7x10 5 L o catio n of P M T A G B M -B G O d etecto r 1836.06 keV In te g ra ted C o u n ts o f P hotopeak S ource A n gle [d e g] 898.04 keV R elative R esponse as a F unction of the O ff-A xis A ngle L o ca tio n of P M T B 0 200 400 600 800 0 10000 20000 30000 40000 50000 60000 G B M -B G O d etecto r 22 N a:511 keV C ounts/C hannel C hannels 22 N a:1274.54 keV 0 1000 2000 3000 4000 0 2000 4000 6000 8000 10000 12000 G B M -NaIdetector 137 C s:32.89 keV C ounts/C hannel C hannels 137 C s:661.66 keV C hannel:2749 FW H M :10.1 % 0 200 400 600 800 0 500 1000 1500 2000 G B M -B G O d etecto r C ounts/C hannel C hannels A m /B e:4.430 M eV FW H M : Irrad iatio n w ith 241 Am / 9 B e source: The 9 Be( ,n) 12 C reaction produces th e firstexcited state of 12 C 12 C * - > (4.43 M eV ) + 12 C (ground state) NaI Low Energy Calibration: Performed at the BESSY synchrotron in Berlin with 4 FM-NaIs: Determination of absolute efficiency at low energies (8- 60 keV) and test of response around Iodine K-Edge Detector Magnetic Susceptibility: The effect of magnetic fields on the shielded NaI-EQM module was tested from - 2 G to + 2 G in 0.5 G steps at the IABG’s MFSA facility. Result: The GBM response will not be affected by the magnetic torquers of the GLAST S/C Introduction: The next large NASA mission in the field of gamma-ray astronomy, GLAST, is scheduled for launch in September 2007. Aside from the main instrument LAT, a gamma-ray telescope for the energy range between ~20 MeV and ~300 GeV, a secondary instrument, the GLAST burst monitor (GBM), is foreseen. Its task is to increase the detection rate of gamma-ray bursts for the LAT and to extend the energy range of the main instrument to lower energies (from ~10 keV to ~30 MeV). The GBM consists of 12 thin NaI- plates, which allow the determination of the angle of incidence of the gamma radiation. These crystals are sensitive in the energy range between ~10 keV and ~1 MeV. Two additional BGO detectors, which are able to detect gamma-rays in the energy range between ~150 keV and ~30 MeV, are responsible for the overlap in energy measurement with the LAT main instrument and the NaI detectors. All flight detectors were already delivered to NASA. This poster gives an overview of the calibration measurements performed by MPE at the detector level before delivery. Typical Spectra: Background-subtracted NaI- and BGO-spectra, recorded at an angle where the detector effective area is maximal (0º). 0 50 100 150 200 250 300 0 5000 10000 15000 20000 G B M -N aIdetector Iodine E scape P eaks: 40 - 28.6 keV = 11.4 keV (IK 1 ) 40 - 32.3 keV = 7.2 keV (IK ) C ounts/C hannel C hannels B essy:40 keV 0 200 400 600 800 0 20000 40000 60000 G B M -B G O d etecto r C ounts/C hannel C hannels 137 C s:661.66 keV 0 1000 2000 3000 4000 0 2000 4000 6000 8000 10000 12000 G B M -N aIdetector 57 C o:14.41 keV (9.2 % ) C ounts/C hannel C hannels 57 C o:122.06 keV (85.6% ) + 136.47 keV (10.7% ) 0 1000 2000 3000 4000 0 2000 4000 6000 G B M -N aIdetector Tl-L 11.1 keV Tl-Sum K 72.11 keV C ounts/C hannel C hannels 203 H g:279.2 keV
description
GLAST Burst Monitor. The calibration of the GLAST Burst Monitor NaI- and BGO-detectors. - PowerPoint PPT Presentation
Transcript of For further information, please contact: [email protected]
For further information, please contact: [email protected]
Purpose of Calibration:- provide performance verification of the GBM detectors. - provide benchmark data to compare with calculated detector response data. - provide accurate, well-characterized data for subsequent scientific analysis.
The GBM-NaI(Tl) Detectors (12 x): The GBM-BGO Detectors (2 x):
The calibration of the GLAST Burst Monitor NaI- and BGO-detectors
by Andreas von Kienlin1, Julia Wagner1, Helmut Steinle1, Narayana Bhat2, Michael S. Briggs2, Roland Diehl1, Gerald J. Fishman3, Jochen Greiner1, R. Marc Kippen4, Chryssa Kouveliotou5, Giselher G. Lichti1, Charles A. Meegan3, William S. Paciesas2, Robert D. Preece2, Robert B. Wilson2
GLAST Burst Monitor
0 5000 10000 15000 20000 25000 30000-0.1
0.0
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1.0
1.1
Tran
smis
sion
Photon Energy [eV]
Be: 200 m 20 Mil Tetratex Silicone Pad: 700 m NaI: Sum
X-ray Transmission of the NaI Entrance Window:The installation of an 0.7 mm thick silicon pad between the Beryllium entrance window and the crystal was necessary so that the brittle NaI crystal is able to survive the environmental conditions during launch. This additional silicon layer caused unfortunately a degradation of the transmissivity at low energies (at 10 keV ~ 30%).
[1] Max-Planck-Institut für extraterrestrische Physik (MPE); [2] University of Alabama (UAH); [3] NASA/Marshall Space-Flight Center (MSFC), [4] Los Alamos National Laboratory (LANL), [5] USRA
z
y
118138
158187.5
40°
45°
HV x
y
133.5154
The Calibration Setup:- allowes the acquisition of spectra at different angles of incidence. - high accuracy due to laser adjustment.
List of Calibration Sources: Calibration Results:The figures below summarize the main measurements performed with the flight detectors. All detectors of the same type showed nearly the same performance and all fulfilled the specified requirements.
0 500 1000 1500 2000 2500 3000 3500
0
200
400
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800
1000
0 500 1000 1500 2000 2500 3000 3500-16-12-8-404
GBM-NaI detector
Ene
rgy
[keV
]
Channel Number
Channel-Energy Relation (parabola) R
esid
ual [
keV
]
Channel Number
0 100 200 300 400 500 600 700 800 900-10
-5
0
5
10
15
20
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35
Linearity of the Channel-Energy Relation - deviation from parabolic relation
GBM-NaI detector
E
nerg
y [%
]
Energy [keV]
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1000
2000
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5000
0 100 200 300 400 500 600-505
1015
Channel
Ene
rgy
[keV
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Channel-Energy Relation (line)
GBM-BGO detector
Res
idua
ls [k
eV]
Channel
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Linearity of the Channel-Energy Relation - deviation from linear relation
GBM-NaI detector
E
nerg
y [%
]
Energy [keV]
0 500 1000 1500 2000 2500 3000 3500 4000 4500 50000
5
10
15
20
25
30
35
40
45
Relative Energy Resolution (FWHM) Arrows: Requirements
GBM-BGO detector
FWH
M [
E/E
in %
]
Energy [keV]0 100 200 300 400 500 600 700 800 900 1000
5
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Realtive Energy Resolution (FWHM) Arrows: Requirements
GBM-NaI detector
FWH
M [
E/E
in %
]
Energy [keV]
10 100 10001
10
100
1000GBM-NaI detector
Effe
ctiv
e A
rea
[cm
2 ]
Energy [keV]
-100 -50 0 50 100 150 200 250 3000
1x105
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3x105
4x105
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6x105
Relative Response as a Function of the Off-Axis Angle
GBM-NaI detector
Location ofPMT + FEE
32.89 keV
Inte
grat
ed C
ount
s of
Pho
tope
ak
Source Angle [deg]
661.66 keV
-200 -150 -100 -50 0 50 100 150 200
3x105
4x105
5x105
6x105
7x105
Location ofPMT A
GBM-BGO detector
1836.06 keV
Inte
grat
ed C
ount
s of
Pho
tope
ak
Source Angle [deg]
898.04 keV
Relative Response as a Function of the Off-Axis Angle
Location ofPMT B
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GBM-BGO detector 22Na: 511 keV
Cou
nts/
Cha
nnel
Channels
22Na: 1274.54 keV
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12000
GBM-NaI detector 137Cs: 32.89 keV
Cou
nts/
Cha
nnel
Channels
137Cs: 661.66 keVChannel: 2749FWHM: 10.1 %
0 200 400 600 8000
500
1000
1500
2000GBM-BGO detector
Cou
nts/
Cha
nnel
Channels
Am/ Be: 4.430 MeVFWHM:
Irradiation with 241Am/ 9Be source: The 9Be(,n)12C reaction produces the first excited state of 12C12C* -> (4.43 MeV) + 12C (ground state)
NaI Low Energy Calibration:Performed at the BESSY synchrotron in Berlin with 4 FM-NaIs: Determination of absolute efficiency at low energies (8- 60 keV) and test of response around Iodine K-Edge
Detector Magnetic Susceptibility:The effect of magnetic fields on the shielded NaI-EQM module was tested from -2 G to + 2 G in 0.5 G steps at the IABG’s MFSA facility. Result: The GBM response will not be affected by the magnetic torquers of the GLAST S/C
Introduction:The next large NASA mission in the field of gamma-ray astronomy, GLAST, is scheduled for launch in September 2007. Aside from the main instrument LAT, a gamma-ray telescope for the energy range between ~20 MeV and ~300 GeV, a secondary instrument, the GLAST burst monitor (GBM), is foreseen. Its task is to increase the detection rate of gamma-ray bursts for the LAT and to extend the energy range of the main instrument to lower energies (from ~10 keV to ~30 MeV). The GBM consists of 12 thin NaI-plates, which allow the determination of the angle of incidence of the gamma radiation. These crystals are sensitive in the energy range between ~10 keV and ~1 MeV. Two additional BGO detectors, which are able to detect gamma-rays in the energy range between ~150 keV and ~30 MeV, are responsible for the overlap in energy measurement with the LAT main instrument and the NaI detectors. All flight detectors were already delivered to NASA. This poster gives an overview of the calibration measurements performed by MPE at the detector level before delivery.
Typical Spectra:Background-subtracted NaI- and BGO-spectra, recorded at an angle where the detector effective area is maximal (0º).
0 50 100 150 200 250 3000
5000
10000
15000
20000GBM-NaI detector
Iodine Escape Peaks:40 - 28.6 keV= 11.4 keV (I K1)
40 - 32.3 keV= 7.2 keV (I K)
Cou
nts/
Cha
nnel
Channels
Bessy: 40 keV
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GBM-BGO detector
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nts/
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nnel
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137Cs: 661.66 keV
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12000GBM-NaI detector
57Co: 14.41 keV (9.2 %)
Cou
nts/
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nnel
Channels
57Co: 122.06 keV (85.6%) + 136.47 keV (10.7%)
0 1000 2000 3000 40000
2000
4000
6000
GBM-NaI detector
Tl-L 11.1 keV
Tl-SumK 72.11 keV
Cou
nts/
Cha
nnel
Channels
203Hg: 279.2 keV
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