Miniature sensors with external dimensions of 10 mm x 10 mm were produced together with full-size sensors for the innermost ring (R0) of the end-cap part in the upgraded ATLAS inner tracker (ITk). ...AC- and DC-coupled n-type strips with three different pitches (wide, default and narrow) were processed on high-resistivity p-type FZ silicon substrates by Hamamatsu Photonics. The miniature sensors were irradiated with 70-MeV protons at CYRIC, Tohoku University (Japan) and reactor neutrons at the Jožef Stefan Institute (Slovenia) to three different 1-MeV neutron equivalent fluences: 0.5, 1 and 2 x 1015neqcm−2. The upper fluence range exceeds the highest anticipated in the innermost part of the ATLAS ITk-Strips over the HL-LHC lifetime (∼1.25 × 1015neqcm2). The charge collection in the test sensors was evaluated systematically using a 90Sr β-source and an Alibava analogue readout system at reverse-bias voltages up to 1000 V.
•The charge collection in the test sensors was evaluated systematically.•The collected charge increases with the applied voltage.•At higher voltages the effect of multiplication can be seen.•The multiplication becomes higher at long annealing times.
The ATLAS detector is now installed at the CERN LHC and a precise evaluation of the radiation environment within and around the detector is required to understand the performance of the various ...detector systems, and to predict their useful lifetime. Furthermore, validation of earlier Monte Carlo predictions about the radiation field in ATLAS is necessary. In particular, it is important to perform these measurements in the early phases of the LHC operation. Many other radiation measuring devices lack sensitivity to low doses, and usually do not provide information on the composition of the radiation during this low intensity period. A network of 15 ATLAS-MPX devices has been installed at various positions in the ATLAS detector. These devices are capable of providing quantitative real-time information on the fluxes and flux distributions of the main radiation types in the experiment, including slow and fast neutrons. The technical description of the ATLAS-MPX detector network as well as the principles of the data analysis is presented.
Optimising the strip geometry for very fine pitch silicon strip sensors Dragicevic, M.; Bergauer, T.; Dolezal, Z. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
05/2010, Letnik:
617, Številka:
1
Journal Article
Recenzirano
Future collider experiments will require tracking detectors with more precise silicon sensors for improved track reconstruction precision and possibly with the ability to provide input to the first ...level trigger. One way to enhance the tracking performance is the minimization of the readout pitch. We investigated the performance of such fine pitch strip sensors using multigeometry testsensors with a fixed readout pitch of
50
μ
m
and a varying number of intermediate strips and different strip widths. Results from a testbeam with
120
GeV
/
c
pions are presented, suggesting the best geometry for optimal spatial resolution. Furthermore we studied the possibility to derive the incidence angle of a particle from the cluster width, which could be used as a tracking trigger on transverse momentum.
The paper is based on the data of the 2009 DEPFET beam test at CERN SPS. The beam test used beams of pions and electrons with energies between 40 and 120
GeV, and the sensors tested were prototypes ...with thickness of
450
μ
m
and pixel pitch between 20 and
32
μ
m
. Intrinsic resolutions of the detectors are calculated by disentangling the contributions of measurement errors and multiple scattering in tracking residuals. Properties of the intrinsic resolution estimates and factors that influence them are discussed. For the DEPFET detectors in the beam test, the calculation yields intrinsic resolutions of
≈
1
μ
m
, with a typical accuracy of
0.1
μ
m
. Bias scan, angle scan, and energy scan are used as example studies to show that the intrinsic resolutions are a useful tool in studies of detector properties. With sufficiently precise telescopes, detailed resolution maps can be constructed and used to study and optimize detector performance.
A new data acquisition program for personal computers with the Windows operating system has been built at Charles University van de Graaff laboratory. It allows fast data acquisition from VME, CAMAC, ...and other PC interface cards using an interrupt or polling mode via several types of crate controllers. The program also facilitates basic on-line analysis and visualization of acquired data in graphs and histograms. The program is written as a combination of MSVC6.0++ and ROOT macros and offers easy customization to individual user requirements via external configuration files, without need of recompilation. A driver interface supports PCI bus devices (W-IE-NE-R PCI-CC32) or older ISA bus devices with internal drivers. In this paper, a description of the program concepts and features is given. The program was extensively tested with several combinations of hardware and software, and results of the tests are shown.
The high luminosity upgrade of the Large Hadron Collider, foreseen for 2027, requires the replacement of the ATLAS Inner Detector with a new all-silicon Inner Tracker (ITk). The expected total ...integrated luminosity of 4000 fb−1 means that the strip part of the ITk detector will be exposed to a large radiation fluence of up to Φeq = 1.6 × 1015 1 MeV neq/cm and an ionizing dose of 0.66 MGy, including a safety factor of 1.5. Radiation-hard n+-in-p micro-strip sensors for use in the ITk have been developed by the ATLAS ITk Strip Sensor collaboration and produced by Hamamatsu Photonics K.K. In this paper, the results obtained from the electrical characterization of the latest barrel ATLAS17LS sensor prototype, before and after irradiation, are shown.
Surface properties of the long-strip barrel, full-sized and miniature sensors have been studied before and after proton, neutron and gamma irradiation up to the maximal fluences and radiation doses specified for the ITk Strip tracker. Sensors have been irradiated by protons at CYRIC, Tohoku University (Japan), the Proton Irradiation Facility at CERN, Karlsruhe Inst. Tech. (Germany) and at the University of Birmingham (UK), by neutrons from the Ljubljana TRIGA reactor (Slovenia) and by gamma rays from the 60Co source in UJP Praha (Czech Republic).
It has been verified that the surface radiation damage does not influence the sensor functionality. The breakdown voltage is well above the maximum operational voltage. All the tested surface parameters, such as the inter-strip resistance and capacitance, coupling capacitance and bias resistance satisfy the ATLAS ITk specifications for strip sensors.
A frozen-spin- polarized deuteron target cooled by the
3He/
4He dilution refrigerator is described. Fully deuterated 1,2-propanediol was used as a target material. Deuteron vector polarization about ...40% was obtained for the target in the shape of a cylinder of 2-cm diameter and 6-cm length. The target is intended for a study of 3N interactions at the polarized neutron beam generated by the Van de Graaff accelerator at the Charles University in Prague.
SiLC R&D: Design, present status and perspectives Lozano, M.; Orava, R.; van Remortel, N. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
09/2007, Letnik:
579, Številka:
2
Journal Article
Recenzirano
Odprti dostop
This paper briefly describes the main R&D objectives that are undertaken within the international R&D collaboration SiLC aiming to build the next generation of silicon tracking devices especially in ...the case of the ILC. Firstly, motivation to use silicon detectors in the tracker is explained. Then basic aspects of the design and solutions proposed are described (sensors, front-end electronics, mechanics, alignment). First results from the lab and beam test of the front-end chips and module prototypes built are shown.
The ATLAS experiment will replace the existing Inner Detector by an all-silicon detector named the Inner Tracker (ITk) for the High Luminosity LHC upgrades. In the outer region of the ITk is the ...strip detector, which consists of a four layer barrel and six discs to each side of the barrel, with silicon-strip modules as basic units. Each module is composed of a sensor and one or more flex circuits that hold the read-out electronics. In the experiment, the modules are mounted on support structures with integrated power and cooling. The modules are designed with geometries that accommodate the central (barrel) and forward (end-cap) regions, with rectangular sensors in the barrels and wedge shaped sensors in the end-caps. The strips lengths and pitch sizes vary according to the occupancy of the region.
In this contribution, we present the construction and results of the electrical tests of the first full-size module of the innermost forward region, named Ring 0 in the ATLAS ITk strip detector nomenclature. This module uses a sensor with stereo annulus geometry, having four segments of strips of different lengths and pitch. The two innermost strips segments are read out through eight chips, for a total of 2048 strips, while the two outermost segments are read out through nine chips, for a total of 2304 strips. We introduce the assembly procedure that lead to the construction of the module as well as the testing during the intermediate steps.