The ALICE experiment will replace its three innermost tracking layers with the Inner Tracking System 3 (ITS3) during LHC Long Shutdown 3. This upgrade introduces the first fully cylindrical, wafer-scale silicon vertex detector, utilising Monolithic Active Pixel Sensors (MAPS) fabricated in a 65nm CMOS process. By thinning sensors to 50$μ$m and bending them to radii as small as 19mm, the design achieves a self-supporting structure that eliminates traditional support material. Wafer-scale stitching enables 27cm-long seamless sensors with integrated power and signal distribution, removing the need for flexible printed circuits within the active volume. These innovations, combined with a move from water to air cooling, reduce the material budget to less than 0.09%X$_0$ per layer.
The R&D program has been validated through full-scale prototypes (MOSS, MOST), which demonstrated stitching feasibility, high yield, and radiation hardness. Engineering models confirmed the feasibility of air-convection cooling, indicating effective thermal management and structural stability. This contribution summarises the key advances in stitched sensor development, mechanical integration, and the path toward the final qualification model.
The ALICE detector is undergoing an upgrade for Run 3 at the LHC. A new Inner Tracking System (ITS) is part of this upgrade. The upgraded ALICE ITS features the ALPIDE, a Monolithic Active Pixel Sensor. Due to IC fabrication variations and radiation damages, the threshold values for the ALPIDE chips in ITS need to be measured and adjusted periodically to ensure the quality of data. The calibration is implemented within the ALICE Online-Offline (O$^2$) Computing System, thus it runs in the same framework as the normal operations. This paper describes the concept and first implementation of the …
The ALICE experiment at CERN has undergone a major upgrade during the Long Shutdown 2 of the LHC during 2019-2021. A key element is the installation of the new Inner Tracking System 2 (ITS2). The new ITS2 based on CMOS Monolithic Active Pixel Sensors will significantly improve the impact parameter resolution and the tracking efficiency, especially for particles with low transverse momenta, as well as the readout-rate capability. In the following, the upgrade and its commissioning status as well installation status will be outlined.
A central component of the ALICE Upgrade will be a completely new Inner Tracking System (ITS). The performance of the new ITS will be a significant improvement over that of the present ITS, in particular in the areas of material budget, granularity, a reduced radial distance from the first layer to the beam and rate capability. This will enable many key measurements of the properties of the quark-gluon plasma to be performed, in particular with rare probes such as low momentum charm and beauty mesons and baryons.
The ALICE experiment profited of the Long Shutdown during 2019-2021 in order to expand its physics capabilities and fully profit from the increased LHC luminosity in Run 3. The Inner Tracking System has been replaced with a new silicon tracker based on MAPS technology, and a new tracking device has been added in front of the Muon Spectrometer to improve its vertexing capabilities. The wire chambers for TPC readout have been replaced with new GEM detectors which will minimize ion backflow and allow for continuous data taking: moreover, a new detector array dedicated to fast triggering has been …
A large Time Projection Chamber (TPC) is the main device for tracking and charged-particle identification in the ALICE experiment at the CERN LHC. After the second long shutdown in 2019-2020, the LHC will deliver Pb beams colliding at an interaction rate of up to 50 kHz, which is about a factor of 50 above the present readout rate of the TPC. To fully exploit the LHC potential, the TPC readout chambers will be upgraded with Gas Electron Multiplier (GEM) technology. To assure stable behaviour of the upgraded chambers in the harsh LHC environment, a dedicated R&D programme was launched in order …
The ALICE Collaboration is planning a major upgrade of its central barrel detectors to be able to cope with the increased LHC luminosity beyond 2020. In order to record at an increased interaction rate of up to 50$\,$kHz in Pb$-$Pb collisions, the TPC will be operated in an ungated mode with continuous readout. This demands for a replacement of the currently employed gated Multi-Wire Proportional Chambers by GEM-based (Gas Electron Multiplier) readout chambers, while retaining the performance in particular in terms of particle identification capabilities via the measurement of the specific ene…
ALICE (A Large Ion Collider Experiment) at the CERN Large Hadron Collider (LHC) is designed to study proton-proton and heavy-ion collisions at ultra-relativistic energies. The main goal of the experiment is to assess the properties of quark gluon plasma, a state of matter where quarks and gluons are de-confined, reached in extreme conditions of temperature and energy density. During the ongoing long shutdown 2 of LHC, ALICE is undergoing a major upgrade of its apparatus, in view of the LHC Run 3, scheduled to start in 2022. The upgrade will allow a new ambitious programme of high-precision mea…
The upgrade of the Inner Tracking System (ITS) of ALICE is planned for the second long shutdown of the LHC in 2019-2020. The ALICE physics program after the shutdown requires the ITS to have improved tracking capabilities and improved impact parameter resolution at very low transverse momentum, as well as a substantial increase in the readout rate. To fulfill these requirements the current ITS will be replaced by seven layers of Monolithic Active Pixel Sensors. The new detector will be moved as close as 23 mm to the interaction point and will have a significantly reduced material budget. Sever…
The LHC with its unprecedented energy offers unique opportunities for groundbreaking measurements in p+p, p+A and A+A collisions even beyond the baseline experimental designs. ALICE is setting up a program of detector upgrades, which could to a large extent be installed in the LHC shutdown planned for 2017/18, to address the new scientific challenges. We will discuss examples of the scientific frontiers and will present the corresponding upgrade projects under study for the ALICE experiment.
The ALICE Experiment has replaced its Inner Tracking System with a 7-layer pixel-only tracker made out of more than 24000 monolithic active pixel sensor chips, in order to fulfill the requirements of the physics program of the LHC Run 3. The upgraded Inner Tracking System (ITS2) has been installed in the ALICE experiment during the LHC long shutdown 2 and has started to take data with the beginning of Run 3 in July 2022, with proton-proton collisions at $\sqrt{s}$ = 13.6 TeV. With its 12.5 billion pixels it is the largest pixel detector installed in a high energy physics experiment to date. To…
ALICE is the general purpose heavy-ion detector at the CERN LHC. Its goal is to investigate the properties of the strongly interacting matter under the extreme conditions of density and temperature reached in Pb{Pb collisions, with the aim to characterize the Quark-Gluon Plasma (QGP). In this scenario, the upgrade of the ALICE inner tracker targets physics topics in which ALICE can bring a unique contribution to the QGP characterization via the heavy avour probes. We present an overview of the inner tracker upgrade and the expected physics performance for heavy avour measurements.
The ALICE Collaboration is planning a major upgrade of its central barrel detectors to be able to cope with the increased LHC luminosity beyond 2020. For the TPC, this implies a replacement of the currently used gated MWPCs (Multi-Wire Proportional Chamber) by GEM (Gas Electron Multiplier) based readout chambers. In order to prove, that the present particle identification capabilities via measurement of the specific energy loss are retained after the upgrade, a prototype of the ALICE IROC (Inner Readout Chamber) has been evaluated in a test beam campaign at the CERN PS. The d$E$/d$x$ resolutio…
In view of Run 4 at the LHC, presently scheduled from 2029 onwards, ALICE is pursuing several upgrades to further extend its physics reach. In order to improve heavy-flavor hadron and dielectron measurements which rely on secondary vertexing, a reduction of the material budget of the innermost layers of the Inner Tracking System is needed. This can be achieved with bent pixel sensors, arranged in half-cylinder shapes with integrated power lines and data buses, allowing to get rid of most of the supporting structure and of the water cooling. Moreover, a new Forward Calorimeter (FoCal), covering…
ALICE (A Large Ion Collider Experiment) is the CERN LHC experiment optimized for the study of the strongly interacting matter produced in heavy-ion collisions and devoted to the characterization of the Quark-Gluon Plasma. To achieve the physics program for LHC Run 3 and 4, ALICE is undergoing a major upgrade of the experimental apparatus during the ongoing second long LHC shutdown. A key element of the ALICE upgrade is the substitution of the Inner Tracking System (ITS) with a completely new silicon-based detector whose features will allow the reconstruction of rare physics channels which coul…
A Large Ion Collider Experiment (ALICE) is built to study the properties of the strongly interacting matter created in heavy-ion collisions at the LHC. With the upgrade of its Inner Tracking System (ITS), the ALICE experiment is going to increase the rate of data taking by almost two orders of magnitude. At the same time, the precision of secondary vertex reconstruction will become by at least a factor 3 better than it currently is. In this talk, we briefly show some selected physics results motivating the upgrade of the ITS, describe the design goals and the layout of the new detector, and hi…
After the Long Shutdown 2 the LHC will provide lead-lead collisions at interaction rates as high as 50kz. In order to cope with such conditions the ALICE Time Projection Chamber (TPC) needs to be upgraded. After the upgrade the TPC will run in a continuous mode, without any degradation of the momentum and dE/dx resolution compared to the performance of the present TPC. Since readout by multi-wire proportional chambers is no longer feasible with these requirements, new technologies have to be employed. In the new readout chambers the electron amplification is provided by a stack of four Gas Ele…
ALICE is the CERN LHC experiment optimised for the study of the strongly interacting matter produced in heavy-ion collisions and devoted to the characterisation of the quark-gluon plasma. To achieve the physics program for LHC Run 3, a major upgrade of the experimental apparatus is ongoing. A key element of the upgrade is the substitution of the Inner Tracking System (ITS) with a completely new silicon-based detector whose features will allow the reconstruction of rare physics channels, not accessible with the previous layout. The enabling technology for such a performance boost is the adoptio…
ALICE is the CERN LHC experiment optimised for the study of the strongly interacting matter produced in heavy-ion collisions and devoted to the characterisation of the quark-gluon plasma. To achieve the physics program for LHC Run 3, a major upgrade of the experimental apparatus is ongoing. A key element of the upgrade is the substitution of the Inner Tracking System (ITS) with a completely new silicon-based detector (ITS 2) whose features will allow the reconstruction of rare physics channels not accessible with the previous layout. The enabling technology for such a performance boost is the …
ALICE (A Large Ion Collider Experiment) experiment at CERN LHC is designed to study the properties of the Quark-Gluon Plasma (QGP) in heavy-ion collisions. In 2019-2020 the upgrade of CERN LHC will increase the luminosity and the collision rate beyond the design parameters of the current ALICE setup. To be able to benefit from the improved performance of the LHC, ALICE will upgrade several of its key detector systems including the Fast Interaction Trigger (FIT) [2]. FIT is designed to provide the functionality of the old forward detectors while retaining or even improving their performance. It…
ALICE is the experiment at the CERN LHC devoted to study heavy-ion collisions. An upgrade program of the ALICE detector is ongoing toward the LHC Run 3 starting in 2022 together with the upgrade of the data acquisition system and the detector control system (DCS). One of the main projects of the current ALICE upgrade program is the addition of the muon forward tracker (MFT), a new silicon pixel detector located at forward rapidity. In this paper, we describe the DCS of the MFT detector which is entirely controlled via a finite state machine in a hierarchical system.
The ALICE (A Large Ion Collider Experiment) experiment at the Large Hadron Collider (LHC) at CERN is dedicated to heavy ion physics to explore the structure of strongly interacting matter. The Time Projection Chamber (TPC) of ALICE is a tracking detector located in the central region of the experiment. It offers excellent tracking capabilities as well as particle identification. After the second long shutdown (LS2) the LHC will run at substantially higher luminosities. To be able to increase the data acquisition rate by a factor of 100, the ALICE TPC experiment has to replace the Multi-Wire Pr…
A large Time Projection Chamber (TPC) is the main device for tracking and charged-particle identification in the ALICE experiment at the CERN LHC. After the second long shutdown in 2019-2020, the LHC will deliver Pb beams colliding at an interaction rate up to 50 kHz, which is about a factor of 100 above the present read-out rate of the TPC. To fully exploit the LHC potential the TPC will be upgraded based on the Gas Electron Multiplier (GEM) technology. A prototype of an ALICE TPC Outer Read-Out Chamber (OROC) was equipped with twelve large-size GEM foils as amplification stage to demonstrate…
The Inner Tracking System (ITS) of the ALICE experiment will be upgraded during the second long LHC shutdown in $\mathrm{2019}-\mathrm{2020}$. The main goal of the ALICE ITS Upgrade is to enable high precision measurements of low - momentum particles (< 1 GeV/c) by acquiring a large sample of events, benefiting from the increase of the LHC instantaneous luminosity of $\mathrm{Pb}-\mathrm{Pb}$ collisions to $\mathcal{L} = 6 \cdot 10^{27} cm^{-2} s^{-1} $ during Run 3. Working in this direction the ITS upgrade project is focusing on the increase of the readout rate, on the improvement of the imp…
ALICE is a general purpose experiment dedicated to the study of nucleus-nucleus collisions at LHC. After more than 3 years of successful operation, an upgrade of the apparatus during the second long shutdown of LHC (LS2) in 2017/18 is in preparation. One of the major goals of the proposed upgrade is to extend the physics reach for rare probes at low transverse momentum. The reconstruction of the rare probes requires a precise determination of the primary and secondary vertices that is performed in ALICE by the Inner Tracking System (ITS). The present ITS made of 6 layers of three technologies …
The ALICE experiment at CERN is undergoing a major upgrade during the Long Shutdown 2 (LS2) of the LHC during 2019-2020. The key elements regarding the central barrel are the installation of a new Inner Tracking System (ITS) and the upgrade of the large Time Projection Chamber (TPC). The TPC is currently being upgraded with a new readout system, including new GEM-based Readout Chambers and new front-end electronics enabling us to operate it in continuous mode. The new ITS based on CMOS Monolithic Active Pixel Sensors will significantly improve the impact parameter resolution and the tracking e…
The Inner Tracking System (ITS) Upgrade for the ALICE experiment at LHC is the first large-area ($\sim$10~m$^2$) silicon vertex detector based on the CMOS Monolithic Active Pixel Sensor (MAPS) technology, which combines sensitive volume and front-end readout logic in the same piece of silicon. This technology allows a reduced material budget (target value of 0.3\% on the innermost layers) thanks to the thin sensors (50-100~$μ$m) and limited need of cooling, in combination with light-material interconnection circuits and support structures. The small pixel pitch ($\sim$30~$μ$m), the location of…
The Inner Tracking System (ITS) is the key ALICE detector for the study of heavy flavour production at LHC. Heavy flavor can be studied via the identification of short-lived hadrons containing heavy quarks which have a mean proper decay length in the order of 100-300 $μ$m. To accomplish this task, the ITS is composed of six cylindrical layers of silicon detectors (two pixel, two drift and two strip) with a radial coverage from 3.9 to 43 cm and a material budget of 1.1% X0 per layer. %In particular, the properties of the two innermost layers define the ITS performance in measuring the displaced…
The ALICE experiment at the Large Hadron Collider at CERN is upgrading its central tracking detector, the Time Projection Chamber (TPC). The installation is foreseen during the second long shutdown of the Large Hadron Collider. The upgrade includes the complete exchange of the present MWPC readout chambers (ROC) with new ones based on Gas Electron Multiplier detectors. This is necessary due to the higher LHC luminosity and thus higher interaction rate. The new ROCs allow for continuous readout at 50 kHz compared to 500 Hz of the gated MWPC readout, while maintaining the particle identification…
A Time Projection Chamber (TPC) is a powerful detector for 3-dimensional tracking and particle identification for ultra-high multiplicity events. It is the central tracking device of many experiments, e.g. the ALICE experiment at CERN. The necessity of a switching electrostatic gate, which prevents ions produced in the amplification region o MWPCs from entering the drift volume, however, restricts its application to trigger rates of the order of 1 kHz. Charge amplification by Gas Electron Multiplier (GEM) foils instead of proportional wires offers an intrinsic suppression of the ion backflow, …
The ALICE Collaboration will undertake a major upgrade of the detector apparatus during the second LHC Long Shutdown LS2 (2019-2020) in view of the Runs 3 and 4 (2021-2029). The objective of the upgrade is two-fold: i) an improvement of the tracking precision and efficiency, in particular in the low-momentum range; ii) an improvement of the readout capabilities of the experiment, in order to fully exploit the luminosity for heavy ions envisaged after LS2. The first goal will be achieved by replacing the Inner Tracking System with a new tracker, composed of seven layers of silicon pixel detecto…
During the Long Shutdown 2 of the LHC in 2018/2019, the ALICE experiment plans the installation of a novel Inner Tracking System. It will replace the current six layer detector system with a seven layer detector using Monolithic Active Pixel Sensors. The upgraded Inner Tracking System will have significantly improved tracking and vertexing capabilities, as well as readout rate to cope with the expected increased Pb-Pb luminosity of the LHC. The choice of Monolithic Active Pixel Sensors has been driven by the specific requirements of ALICE as a heavy ion experiment dealing with rare processes a…
The ALICE Muon Trigger is currently yielded by a detector currently composed of 72 Bakelite single-gap Resistive Plate Chambers operated in maxi-avalanche mode, arranged in four 5.5x6.5 m2 detection planes. In order to meet the requirements posed by the forthcoming LHC high luminosity runs starting from 2021 onwards, in which ALICE will be read out in continuous mode, the Muon Trigger will become a Muon Identifier and will undergo a major upgrade. In the current setup, signals from about 21k strips are discriminated by 2400 non-amplified Front End (FEE) cards, whose thresholds are provided by …
In LHC Run 3, ALICE will increase the data taking rate significantly to 50 kHz continuous readout of minimum bias Pb--Pb collisions. The reconstruction strategy of the online-offline computing upgrade foresees a first synchronous online reconstruction stage during data taking enabling detector calibration, and a posterior calibrated asynchronous reconstruction stage. The main challenges include processing and compression of 50 times more events per second than in Run 2, identification of removable TPC tracks and hits not used for physics, tracking of TPC data in continuous readout, the TPC spa…
The ALICE experiment at the Large Hadron Collider (LHC) proposes major detector upgrades to fully exploit the increase of the luminosity of the LHC in RUN~3 and to extend the physics reach for rare probes at low transverse momentum. The Time Projection Chamber (TPC) is one of the main tracking and PID devices in the central barrel of ALICE. The maximum trigger rate of the TPC is currently limited to about 3.5 kHz by the operation of a gating grid system. In order to make full use of the luminosity in RUN 3, the TPC is foreseen to be operated in an ungated mode with continuous readout. The exis…
A Large Ion Collider Experiment (ALICE) at the Large Hadron Collider (LHC) at CERN went through a major upgrade in which some of its subdetectors were replaced with new ones, while others are equipped with new electronics. The aim of the upgrade is to withstand higher collision rates during the third running period (Run 3), which started in 2022. As part of the upgrade, certain subdetectors such as the Muon Trigger, renamed to Muon Identifier, now operate in a continuous, triggerless readout mode, in addition to the previous triggered readout mode. Due to the increased quantity of data, typica…
The ALICE Collaboration completed the upgrade of the detector and is now commissioning for the beginning of the data taking during LHC Run 3. In parallel, R&D activities and simulation studies are being performed to define the future of the experiment beyond LHC Run 3. Two detector upgrades are foreseen for the next long shutdown (LS3). The first is the replacement of the three layers of the inner tracking system closest to the beam with a novel vertex detector consisting of curved wafer-scale ultra-thin silicon sensors arranged in perfectly cylindrical layers to improve impact parameter resol…
ALICE, one of the experiments at the Large Hadron Collider (CERN), is undergoing ambitious upgrades during the ongoing second long shutdown (LS2). The main goal of this project is to access rare events and previously inaccessible physics observables. The increased Pb-Pb and pp collision rates need a correspondingly higher TPC operation rate in the next Run 3 of the LHC. The operational gated MWPC readout used so far cannot be used at such fast rates. Therefore a new readout chamber is needed with a novel technology and without any compromise on the momentum and energy resolution. As a solution…
A new type of Time Projection Chamber (TPC) has been proposed for the upgrade of the ALICE (A Large Ion Collider Experiment at CERN) so as to cater to the high luminosity environment expected at the Large Hadron Collider (LHC) facility in future. This device will rely on the intrinsic ion back flow (IBF) suppression of Micro-Pattern Gas Detectors (MPGD) based technology in particular the Gas Electron Multiplier (GEM). GEM is to minimise the space charge effect in the main drift volume and thus will not require the standard gating grid and the resulting intrinsic dead time. It will thus be poss…
The ALICE experiment at CERN is preparing for a major upgrade for the third phase of data taking run (Run 3), when the high luminosity phase of the Large Hadron Collider (LHC) starts. The increase in the beam luminosity will result in high interaction rate causing the data acquisition rate to exceed 3 TB/sec. In order to acquire data for all the events and to handle the increased data rate, a transition in the readout electronics architecture from the triggered to the trigger-less acquisition mode is required. In this new architecture, a dedicated electronics block called the Common Readout Un…
The LHCb experiment is one of the four large detectors operating at the LHC at CERN and it is mainly devoted to CP violation measurements and to the search for new physics in rare decays of beauty and charm hadrons. The data from the two Ring Image Cherenkov (RICH-1 and RICH-2) detectors are essential to identify particles in a wide momentum range. From 2019 onwards 14 TeV collisions with luminosities reaching up to $2\cdot10^{33}$ cm$^{-2}$ s$^{-1}$ with 25 ns bunch spacing are planned, with the goal of collecting 5 fb$^{-1}$ of data per year. In order to avoid degradation of the PID performa…
ALICE is one of the four experiments at the CERN Large Hadron Collider (LHC) specifically designed to study nuclear matter at extreme conditions of temperature and pressure. The LHC Run 3 started officially in July 2022 with proton-proton (pp) collisions at a centre-of-mass energy $\sqrt{s}$ = 13.6 TeV after a shutdown of more than two years to allow for the upgrade of both the accelerator and the experiments. To fulfill the requirements of the ALICE physics program for Run 3, new timing, tracking and multiplicity detectors have been installed in the ALICE central barrel both at mid- and forwa…
The ALICE Collaboration aims at studying the physics of strongly interacting matter by building up a dedicated heavy-ion detector. The Inner Tracking System (ITS) is located in the heart of the ALICE Detector surrounding the interaction point. Now, ALICE has a plan to upgrade the inner tracking system for rare probes at low transverse momentum. The new ITS composes of seven layers of silicon pixel sensor on the supporting structure. One goal of the new design is to reduce the material budget ($X/X_0$) per layer to 0.3$\%$ for inner layers and 0.8$\%$ for middle and outer layers. In this work, …
A large Time Projection Chamber is the main device for tracking and charged-particle identification in the ALICE experiment at the CERN LHC. After the second long shutdown in 2019/20, the LHC will deliver Pb beams colliding at an interaction rate of about 50 kHz, which is about a factor of 50 above the present readout rate of the TPC. This will result in a significant improvement on the sensitivity to rare probes that are considered key observables to characterize the QCD matter created in such collisions. In order to make full use of this luminosity, the currently used gated Multi-Wire Propor…
The Large Hadron Collider (LHC) at CERN is undergoing a major upgrade with the goal of increasing the luminosity as more statistics are needed for precision measurements. The presented work pertains to the corresponding upgrade of the ALICE Muon Trigger (MTR) Detector, now named the Muon Identifier (MID). Previously operated in a triggered readout manner, this detector has transitioned to continuous readout with time-delimited data payloads. However, this results in data rates much higher than the previous operation and hence a new Online-Offline (O2) computing system is also being developed f…
