Overview of the ATLAS Insertable B-Layer (IBL) Project Røhne, O.
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2013, Letnik:
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The upgrades for the ATLAS Pixel Detector will be staged in preparation for high luminosity LHC. The first upgrade for the Pixel Detector is the construction of a new pixel layer which will be ...installed during the first shutdown of the LHC machine, in 2013–2014. The new detector, called the Insertable B-Layer (IBL), will be installed between the existing Pixel Detector and a new, smaller radius beam-pipe at a radius of 3.3cm. The IBL has required the development of several new technologies to cope with increased radiation and pixel occupancy and also to improve the physics performance through reduction of the pixel size and a more stringent material budget. The IBL presents several changes to the design of the present ATLAS Pixel Detector: two different and promising silicon sensor technologies, planar n-in-n and 3D, will be used for the IBL. A new read-out chip FE-I4 has been designed in 130nm technology, the material budget is minimized by using new lightweight mechanical support materials and a CO2 based cooling system has been developed. An overview of the IBL project, of the module design and the qualification for these sensor technologies with particular emphasis on irradiation and beam tests will be presented.
The AEgIS experiment located at the Antiproton Decelerator at CERN aims to measure the gravitational fall of a cold antihydrogen pulsed beam. The precise observation of the antiatoms in the Earth ...gravitational field requires a controlled production and manipulation of antihydrogen. The neutral antimatter is obtained via a charge exchange reaction between a cold plasma of antiprotons from ELENA decelerator and a pulse of Rydberg positronium atoms. The current custom electronics designed to operate the 5 and 1 T Penning traps are going to be replaced by a control system based on the ARTIQ & Sinara open hardware and software ecosystem. This solution is present in many atomic, molecular and optical physics experiments and devices such as quantum computers. We report the status of the implementation as well as the main features of the new control system.
The primary goal of the AEgIS collaboration at CERN is to measure the gravitational acceleration on neutral antimatter. Positronium (Ps), the bound state of an electron and a positron, is a suitable ...candidate for a force-sensitive inertial measurement by means of deflectometry/interferometry. In order to conduct such an experiment, the impact position and time of arrival of Ps atoms at the detector must be detected simultaneously. The detection of a low-velocity Ps beam with a spatial resolution of (88 ± 5) μm was previously demonstrated 1. Based on the methodology employed in 1 and 2, a hybrid imaging/timing detector with increased spatial resolution of about 10 μm was developed. The performance of a prototype was tested with a positron beam. The concept of the detector and first results are presented.
COMPET is a MRI compatible preclinical PET scanner aiming towards a high sensitivity and a high point source resolution (PSR) by implementing a novel block detector geometry. Layers of matrices ...consisting of long LYSO crystals and wavelength shifter (WLS) fibers are used to determine the point of interaction (POI) of the
γ
‐ray
within the LYSO crystal. This reduces the parallax error to a minimum and allows for a high PSR and a high sensitivity, while keeping a low number of readout channels. Simulations show that the detector achieves a PSR below 1
mm in the transaxial plane and a sensitivity of up to 16%.
COMPET is a preclinical PET scanner aiming towards a high sensitivity, a high resolution and MRI compatibility by implementing a novel detector geometry. In this approach, long scintillating LYSO ...crystals are used to absorb the γ-rays. To determine the point of interaction (POI) between γ-ray and crystal, the light exiting the crystals on one of the long sides is collected with wavelength shifters (WLS) perpendicularly arranged to the crystals. This concept has two main advantages: (1) The parallax error is reduced to a minimum and is equal for the whole field of view (FOV). (2) The POI and its energy deposit is known in all three dimension with a high resolution, allowing for the reconstruction of Compton scattered γ-rays. Point (1) leads to a uniform point source resolution (PSR) distribution over the whole FOV, and also allows to place the detector close to the object being imaged. Both points (1) and (2) lead to an increased sensitivity and allow for both high resolution and sensitivity at the same time, while keeping a low number of readout channels.
In total, COMPET incorporates 1080 readout channels (600 crystals, 480 WLS). It has an axial FOV of 80mm and adjustable bore opening between 30mm and 80mm. It consists of four modules with five layers each. Simulations show a PSR of below 1mm in the transaxial plane and a sensitivity of up to 16% in the center of the FOV. The readout is based on time over threshold signals, sampled with an FPGA, which allows for the measurement of high event rates at the order of mega-counts per seconds. Its compact design and compatibility to high magnetic fields will allow to use it as an insert for an already existing MRI scanner.
A first semi-layer with 12 WLS and 10 LYSO crystal was built and connected to the COMPET readout system. Coincidence data between this module and a tagger crystal using a small Ge-68 and a 60MBq F-18 source was taken.
Abstract
The High Luminosity LHC (HL-LHC) upgrade requires the
planned Inner Tracker (ITk) of the ATLAS detector to tolerate
extremely high radiation doses. Specifically, the innermost parts of
the ...pixel system will have to withstand radiation fluences above
1 × 10
16
n
eq
cm
-2
. Novel 3D silicon pixel
sensors offer a superior radiation tolerance compared to
conventional planar pixel sensors, and are thus excellent candidates
for the innermost parts of the ITk. This paper presents studies of
3D pixel sensors with pixel size 50 × 50 μm
2
mounted
on the RD53A prototype readout chip. Following a description of the
design and fabrication steps, Test Beam results are presented for
unirradiated as well as heavily irradiated sensors. For particles
passing at perpendicular incidence, it is shown that average
efficiencies above 96% are reached for sensors exposed to fluences
of 1 × 10
16
n
eq
cm
-2
when biased to 80 V.
A powerful and robust control system is a crucial, often neglected, pillar of any modern, complex physics experiment that requires the management of a multitude of different devices and their precise ...time synchronisation. The AEḡIS collaboration presents CIRCUS, a novel, autonomous control system optimised for time-critical experiments such as those at CERN’s Antiproton Decelerator and, more broadly, in atomic and quantum physics research. Its setup is based on Sinara/ARTIQ and TALOS, integrating the ALPACA analysis pipeline, the last two developed entirely in AEḡIS. It is suitable for strict synchronicity requirements and repeatable, automated operation of experiments, culminating in autonomous parameter optimisation via feedback from real-time data analysis. CIRCUS has been successfully deployed and tested in AEḡIS; being experiment-agnostic and released open-source, other experiments can leverage its capabilities.
The goal of the AEgIS experiment at the Antiproton Decelerator (AD) at CERN, is to measure directly the Earth's gravitational acceleration on antimatter by measuring the free fall of a pulsed, cold ...antihydrogen beam. The final position of the falling antihydrogen will be detected by a position sensitive detector. This detector will consist of an active silicon part, where the annihilations take place, followed by an emulsion part. Together, they allow to achieve 1% precision on the measurement of g with about 600 reconstructed and time tagged annihilations. We present here the prospects for the development of the AEgIS silicon position sentive detector and the results from the first beam tests on a monolithic silicon pixel sensor, along with a comparison to Monte Carlo simulations.
We report on laser cooling of a large fraction of positronium (Ps) in free flight by strongly saturating the 1 3 S − 2 3 P transition with a broadband, long-pulsed 243 nm alexandrite laser. The ...ground state Ps cloud is produced in a magnetic and electric field-free environment. We observe two different laser-induced effects. The first effect is an increase in the number of atoms in the ground state after the time Ps has spent in the long-lived 2 3 P states. The second effect is one-dimensional Doppler cooling of Ps, reducing the cloud’s temperature from 380(20) to 170(20) K. We demonstrate a 58(9)% increase in the fraction of Ps atoms with v 1 D < 3.7 × 10 4 m s − 1 . Published by the American Physical Society 2024
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