Activation properties of Schottky CdTe diodes irradiated by 150 MeV protons

Murakami, Masanori; Kobayashi, Y.; Kokubun, M.; Takahashi, Isao; Okada, Y.; Kawaharada, Madoka; Nakazawa, K.; Watanabe, Shin; Sato, G.; Kouda, M.; Mitani, Takefumi; Takahashi, Tadayuki; Suzuki, Mitsuaki; Tashiro, M.; Kawasoe, S.; Nomachi, M.; Makishima, Kazuo

doi:10.1109/tns.2003.815120

Cited by 18 publications

(8 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although we already have a simulation framework that will be applicable to various types of future missions, the hadron physics model and its relevant databases should be verified by measurement (e.g., ground-based tests at proton-beam facilities). It is extremely useful to conduct a series of highprecision measurements at different time-scales (to cover a broad lifetime range) after a proton beam irradiation of materials used in instruments [29] for calibrating the model and databases. The input radiation to the simulation should also depend more extensively on the measurement.…”

Section: Discussionmentioning

confidence: 99%

Modeling of proton-induced radioactivation background in hard X-ray telescopes: Geant4-based simulation and its demonstration by Hitomi’s measurement in a low Earth orbit

Odaka

Asai

Hagino

et al. 2018

Nuclear Instruments and Methods in Physics Research Section A:

View full text Add to dashboard Cite

Hard X-ray astronomical observatories in orbit suffer from a significant amount of background due to radioactivation induced by cosmic-ray protons and/or geomagnetically trapped protons. Within the framework of a full Monte Carlo simulation, we present modeling of in-orbit instrumental background which is dominated by radioactivation. To reduce the computation time required by straightforward simulations of delayed emissions from activated isotopes, we insert a semi-analytical calculation that converts production probabilities of radioactive isotopes by interaction of the primary protons into decay rates at measurement time of all secondary isotopes. Therefore, our simulation method is separated into three steps: (1) simulation of isotope production, (2) semi-analytical conversion to decay rates, and (3) simulation of decays of the isotopes at measurement time. This method is verified by a simple setup that has a CdTe semiconductor detector, and shows a 100-fold improvement in efficiency over the straightforward simulation. To demonstrate its experimental performance, the simulation framework was tested against data measured with a CdTe sensor in the Hard Preprint submitted to Nuclear Instruments and Methods in Physics Research Section A X-ray Imager onboard the Hitomi X-ray Astronomy Satellite, which was put into a low Earth orbit with an altitude of 570 km and an inclination of 31 • , and thus experienced a large amount of irradiation from geomagnetically trapped protons during its passages through the South Atlantic Anomaly. The simulation is able to treat full histories of the proton irradiation and multiple measurement windows. The simulation results agree very well with the measured data, showing that the measured background is well described by the combination of proton-induced radioactivation of the CdTe detector itself and thick Bi 4 Ge 3 O 12 scintillator shields, leakage of cosmic X-ray background and albedo gamma-ray radiation, and emissions from naturally contaminated isotopes in the detector system.

show abstract

Section: Discussionmentioning

confidence: 99%

Modeling of proton-induced radioactivation background in hard X-ray telescopes: Geant4-based simulation and its demonstration by Hitomi’s measurement in a low Earth orbit

Odaka

Asai

Hagino

et al. 2018

Nuclear Instruments and Methods in Physics Research Section A:

View full text Add to dashboard Cite

show abstract

“…17 The spectrum of the activation background (blue dashed curve) is estimated from experimental results on the radioactivities induced by mono-energetic protons. 18 The flux is scaled by a rejection factor expected from constraints by the Compton kinematics. The signal fluxes corresponding to 1/100 and 1/1000 of the Crab brightness are overlaid in black and orange dotted straight lines, respectively.…”

Section: Expected Scientific Performancementioning

confidence: 99%

Soft gamma-ray detector for the ASTRO-H Mission

Tajima

Blandford

Enoto

et al. 2010

Space Telescopes and Instrumentation 2010: Ultraviolet to Gamma Ray

View full text Add to dashboard Cite

ASTRO-H is the next generation JAXA X-ray satellite, intended to carry instruments with broad energy coverage and exquisite energy resolution. The Soft Gamma-ray Detector (SGD) is one of ASTRO-H instruments and will feature wide energy band (40-600 keV) at a background level 10 times better than the current instruments on orbit. SGD is complimentary to ASTRO-H's Hard X-ray Imager covering the energy range of 5-80 keV. The SGD achieves low background by combining a Compton camera scheme with a narrow field-of-view active shield where Compton kinematics is utilized to reject backgrounds. The Compton camera in the SGD is realized as a hybrid semiconductor detector system which consists of silicon and CdTe (cadmium telluride) sensors. Good energy resolution is afforded by semiconductor sensors, and it results in good background rejection capability due to better constraints on Compton kinematics. Utilization of Compton kinematics also makes the SGD sensitive to the gamma-ray polarization, opening up a new window to study properties of gamma-ray emission processes. The ASTRO-H mission is approved by ISAS/JAXA to proceed to a detailed design phase with an expected launch in 2014. In this paper, we present science drivers and concept of the SGD instrument followed by detailed description of the instrument and expected performance.

show abstract

“…3 shows the expected spectra of the internal backgrounds for 0.5 mm thick CdTe and 5 mm thick GSO after activation assuming the low earth orbit similar to the Astro-E2 sattellite. These spectra are estimated from experimental results on the radioactivities induced by monoenergetic protons [17], [20] It clearly illustrates that the continuum background is reduced by more than an order of magnitude.…”

Section: Background Suppressionmentioning

confidence: 99%

Design and performance of the soft gamma-ray detector for the NeXT mission

Tajima

Kamae

Madejski

et al. 2005

IEEE Trans. Nucl. Sci.

Self Cite

View full text Add to dashboard Cite

The Soft Gamma-ray Detector (SGD) on board the NeXT (Japanese future high energy astrophysics mission) is a Compton telescope with narrow field of view (FOV), which utilizes Compton kinematics to enhance its background rejection capabilities. It is realized as a hybrid semiconductor gamma-ray detector which consists of silicon and CdTe (cadmium telluride) detectors. It can detect photons in a wide energy band (0.05-1 MeV) at a background level of 5 × 10 −7 counts/s/cm 2 /keV; the silicon layers are required to improve the performance at a lower energy band (<0.3 MeV). Excellent energy resolution is the key feature of the SGD, allowing it to achieve both high angular resolution and good background rejection capability. An additional capability of the SGD, its ability to measure gamma-ray polarization, opens up a new window to study properties of astronomical objects. We will present the development of key technologies to realize the SGD: high quality CdTe, low noise front-end ASIC and bump bonding technology. Energy resolutions of 1.7 keV (FWHM) for CdTe pixel detectors and 1.1 keV for Si strip detectors have been measured. We also present the validation of Monte Carlo simulation used to evaluate the performance of the SGD.

show abstract

Activation properties of Schottky CdTe diodes irradiated by 150 MeV protons

Cited by 18 publications

References 13 publications

Modeling of proton-induced radioactivation background in hard X-ray telescopes: Geant4-based simulation and its demonstration by Hitomi’s measurement in a low Earth orbit

Modeling of proton-induced radioactivation background in hard X-ray telescopes: Geant4-based simulation and its demonstration by Hitomi’s measurement in a low Earth orbit

Soft gamma-ray detector for the ASTRO-H Mission

Design and performance of the soft gamma-ray detector for the NeXT mission

Contact Info

Product

Resources

About