Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userRadiation Damage and Long-Term Aging in Gas Detectors
74
0
0.0
(
0
)
Authors
Maxim Titov
Ask ChatGPT about the research
No Arabic abstract
Aging phenomena constitute one of the most complex and serious potential problems which could limit, or severely impair, the use of gaseous detectors in unprecedented harsh radiation environments. Long-term operation in high-intensity experiments of the LHC-era not only demands extraordinary radiation hardness of construction materials and gas mixtures but also very specific and appropriate assembly procedures and quality checks during detector construction and testing. Recent experimental data from hadron beams is discussed. It is shown that the initial stage of radiation tests, usually performed under isolated laboratory conditions, may not offer the full information needed to extrapolate to the long-term performance of real and full-size detectors at high energy physics facilities. Major factors, closely related to the capability of operating at large localized ionization densities, and which could lead to operation instabilities and subsequent aging phenomena in gaseous detectors, are summarized. Finally, an overview of aging experience with state-of-the-art gas detectors in experiments with low- and high-intensity radiation environments is given with a goal of providing a set of rules, along with some caveat, for the construction and operation of gaseous detectors in high luminosity experiments.
rate research
Read More
The motivation for investigating the use of GaAs as a material for detecting particles in experiments for High Energy Physics (HEP) arose from its perceived resistance to radiation damage. This is a vital requirement for detector materials that are to be used in experiments at future accelerators where the radiation environments would exclude all but the most radiation resistant of detector types.
Radiation damage effects represent one of the limits for technologies to be used in harsh radiation environments as space, radiotherapy treatment, high-energy phisics colliders. Different technologies have known tolerances to different radiation fields and should be taken into account to avoid unexpected failures which may lead to unrecoverable damages to scientific missions or patient health.
In this work we propose the application of a radiation damage model based on the introduction of deep level traps/recombination centers suitable for device level numerical simulation of radiation detectors at very high fluences (e.g. 1{div}2 10^16 1-MeV equivalent neutrons per square centimeter) combined with a surface damage model developed by using experimental parameters extracted from measurements from gamma irradiated p-type dedicated test structures.
Soon after launch, the Advanced CCD Imaging Spectrometer (ACIS), one of the focal plane instruments on the Chandra X-ray Observatory, suffered radiation damage from exposure to soft protons during passages through the Earths radiation belts. Current operations require ACIS to be protected during radiation belt passages to prevent this type of damage, but there remains a much slower and more gradual increase. We present the history of ACIS charge transfer inefficiency (CTI), and other measures of radiation damage, from January 2000 through June 2005. The rate of CTI increase is low, of order 1e-6 per year, with no indication of step-function increases due to specific solar events. Based on the time history and CCD location of the CTI increase, we speculate on the nature of the damaging particles.
The LHCb Vertex Locator (VELO) is a silicon strip detector designed to reconstruct charged particle trajectories and vertices produced at the LHCb interaction region. During the first two years of data collection, the 84 VELO sensors have been exposed to a range of fluences up to a maximum value of approximately $rm{45 times 10^{12},1,MeV}$ neutron equivalent ($rm{1,MeV,n_{eq}}$). At the operational sensor temperature of approximately $-7,^{circ}rm{C}$, the average rate of sensor current increase is $18,upmurm{A}$ per $rm{fb^{-1}}$, in excellent agreement with predictions. The silicon effective bandgap has been determined using current versus temperature scan data after irradiation, with an average value of $E_{g}=1.16pm0.03pm0.04,rm{eV}$ obtained. The first observation of n-on-n sensor type inversion at the LHC has been made, occurring at a fluence of around $15 times 10 ^{12}$ of $1,rm{MeV,n_{eq}}$. The only n-on-p sensors in use at the LHC have also been studied. With an initial fluence of approximately $rm{3 times 10^{12},1,MeV,n_{eq}}$, a decrease in the Effective Depletion Voltage (EDV) of around 25,V is observed, attributed to oxygen induced removal of boron interstitial sites. Following this initial decrease, the EDV increases at a comparable rate to the type inverted n-on-n type sensors, with rates of $(1.43pm 0.16) times 10 ^{-12},rm{V} / , 1 , rm{MeV,n_{eq}}$ and $(1.35pm 0.25) times 10 ^{-12},rm{V} / , 1 , rm{MeV,n_{eq}}$ measured for n-on-p and n-on-n type sensors, respectively. A reduction in the charge collection efficiency due to an unexpected effect involving the second metal layer readout lines is observed.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
