Elena Voevodina

In the present paper we report the development of the Continuous Motion scanning technique and its implementation for a new generation of scanning systems. The same hardware setup has demonstrated a significant boost in the scanning speed, reaching 190 cm2/h. The implementation of the Continuous Motion technique in the LASSO framework, as well as a number of new corrections introduced are described in details. The performance of the system, the results of an efficiency measurement and potential applications of the technique are discussed.

Somatic burden has become one of the most common psychological reactions to the COVID-19 pandemic worldwide. This study examined the prevalence of somatic burden, latent profiles, and associated factors of somatic symptoms during the pandemic in a large sample of Russians. We used cross-sectional data from 10,205 Russians collected during October-December, 2021. Prevalence of somatic burden was assessed with the Somatic Symptom Scale-8. Latent profiles of somatic burden were identified using latent profile analysis. Multinomial logistic regression was used to examine demographic, socioeconomic, and psychological associated factors of somatic burden. Over one-third (37%) of the Russians reported being somatised. We selected the three-latent profile solution with high somatic burden profile (16%), medium somatic burden profile (37%), and low somatic burden profile (47%). The associated factors of greater somatic burden were female gender, lower education, history of COVID-19 disease, refusing vaccination against SARS-CoV-2 infection, poorer self-rated health, greater fear of COVID-19 pandemic, and living in regions with higher excess mortality. Overall, this study contributes to knowledge about the prevalence, latent profiles, and associated factors of somatic burden during the COVID-19 pandemic. It can be useful to researchers in psychosomatic medicine and practitioners in the health care system.

The CMS experiment, located at the Large Hadron Collider (LHC) in CERN, has a redundant muon system composed by three different gaseous detector technologies: Cathode Strip Chambers (in the forward regions), Drift Tubes (in the central region), and Resistive Plate Chambers (both its central and forward regions). All three are used for muon reconstruction and triggering. The CMS RPC system confers robustness and redundancy to the muon trigger. The RPC system operation in the challenging background and pileup conditions of the LHC environment is presented. The RPC system provides information to all muon track finders and thus contributing to both muon trigger and reconstruction. The summary of the detector performance results obtained with proton-proton collision at √s = 13 TeV during 2016 and 2017 data taking have been presented. The stability of the system is presented in terms of efficiency and cluster size vs time and increasing instantaneous luminosity. Data-driven predictions about the expected performance during High Luminosity LHC (HL-LHC) stage have been reported.

In view of the High-Luminosity LHC (HL-LHC) phase, the Resistive Plate Chambers (RPC) system of the Compact Muon Solenoid (CMS) experiment will be extended by installing a new generation of improved-RPC. In the present study, a GEANT4 Monte Carlo simulation study has been done to estimate the background rate on the iRPCs expected in the future runs of HL-LHC.

Four double-gap CMS resistive plate chambers are being tested at the CERN Gamma Irradiation Facility to determine the performance and aging effects at the expected conditions of the High Luminosity-Large Hadron Collider. Results up to an integrated charge of 290 millicoulomb/cm2 are reported.

With the increase of the LHC luminosity foreseen in the coming years, many detectors currently used in the different LHC experiments will be dramatically impacted and some need to be replaced or upgraded. The new ones should be capable to provide time information to reduce the data ambiguity due to the expected high pileup. We propose to equip CMS high |η| muon chambers with pairs of single gap RPC detectors read out by long pickup strips PCB. The precise time measurement (0<15 ps) of the signal induced by particles crossing the detector on both ends of each strip will give an accurate measurement of the position of the incoming particle along the strip. The absolute time measurement, determined by RPC signal (around 1.5 ns) will also reduce the data ambiguity due to the highly expected pileup and help to identify Heavy Stable Charged Particles (HSCP). The development of a specific electronic chain (analog front-end ASIC, time-to-digital converter stage and printed circuit board design) and the corresponding first results on prototype chambers are presented.

The high luminosity expected from the HL-LHC will be a challenge for the CMS detector. The increased rate of particles coming from the collisions and the radioactivity induced in the detector material could cause significant damage and result in a progressive degradation of its performance. Simulation studies are very useful in these scenarios as they allow one to study the radiation environment and the impact on detector performance. Results are presented for CMS RPC stations considering the operating conditions expected at the HL-LHC.

In the next long shutdown for the Phase-2 Upgrade of the Large Hadron Collider (LHC) in 2026–2028, the 96 new integrated muon tracking and trigger modules will be installed at the ends of the toroid magnet coils in the small azimuthal sectors of the inner barrel layer (BIS1-6) of the ATLAS muon spectrometer in order to increase the trigger efficiency in the barrel region and to improve the rate capability of the muon chambers in the regions of high background rate corresponding to the High Luminosity-LHC project. The new muon module consists of the smallDiameter Muon Drift Tube (sMDT) chamber with a 15 mm tube diameter and thin-gap Resistive Plate Chamber (RPC) triplet with 1 mm gas gap thickness. Due to the narrow available space, the BIS1-6 project foresees to replace the all-existing Monitored Drift Tubes, used for the precise position measurement in this area, with muon stations formed by sMDT and RPC, capable of withstanding the higher rates and provide a robust standalone muon confirmation. Moreover, the advantages of sMDT technology are not only to make room for the new trigger chambers, but it has already demonstrated their excellent precise tracking measurement over large areas at high background rates. In the next few years, ATLAS MDT group of the Max Planck Institute for Physics (MPI) in Munich will produce the 48 sMDT detectors with a total number of the drift tube of about 27000. For this reason, the detailed common assembly protocol and quality control procedures have been established, with the ambitious goal to ensure standardization of the performance of the constructed detectors and their components. In this contribution, we present the final results of the QC tests performed on the 48 BIS1-6 sMDT chambers assembled by the MPI Munich production site following the well-defined specification parameters.

Working memory is a crucial cognitive function for processing and storing information in short-term memory during purposeful activities [1]. Numerous studies using EEG, MEG, and stereo-EEG were conducted to identify the neurophysiological correlates of working memory, including oscillations in specific brain regions in the absence of a memorized stimulus. The studies explored multiple aspects such as encoding, maintenance, processing, ordering, updating, and inhibition and various working memory modalities. Additionally, the studies highlighted the significance of examining the functional connectivity between different brain regions. As a result, researchers have amassed a large amount of data that is often contradictory and lacks organization [2]. The aim of this study is to perform a methodical review of literature published from 1980 up to the present period, cataloged in the Scopus, Web of Science, and Pubmed databases. The systematic review follows the PICo structure and addresses three main questions: which neuronal networks are involved in different working memory modalities and detect synchronizations between and within frequencies in cognitively safe subjects; are there disparities in the characteristics of neuronal networks between adults and the elderly; and can various interventions be employed to align the characteristics of neuronal networks in the elderly with those of adults [3]. The systematic review follows PRISMA-P 2015 protocol [4]. Main inclusion criteria focus on investigating working memory, analyzing visual, verbal and nonspecific modalities, using EEG/MEG/stereo-EEG, assessing adult and elderly subjects, and providing quantitative results from behavioral and neurocognitive research. Exclusion criteria: The study excluded emotional stimuli and assessments of long-term memory as well as the use of fMRI. Additionally, unigender studies and studies with subjects who had cognitive or other impairments were not included. In addition, the study required a sufficient number of subjects and time-frequency analysis. Moreover, physical or dietary interventions were excluded, and experimental research was necessary for inclusion. The study did not assess working memory in a foreign language for the subjects. A systematic review was conducted on the platform nested-knowledge.com. Based on the given criteria, a literature search was performed, yielding 2,828 articles meeting the inclusion criteria. These were further screened by two experts, resulting in the identification of 234 relevant articles, and upon full text review, 89 articles were deemed relevant. The resulting pool of articles is characterized by the following parameters: 69 articles describe adult subjects, 5 articles describe elderly subjects, and 12 articles compare both groups. Additionally, 42 articles focus on oscillation, 15 on functional connectivity, and 32 on both metrics. Concerning working memory, 22 articles describe all stages, 8 focus on encoding, 11 on encoding and maintenance, 4 on maintenance and recall, 23 on maintenance, 9 on maintenance and processing, 7 on processing, 1 on recall, and 3 without separating stages. Furthermore, 28 articles pertain to verbal memory, 51 to visual memory, 8 articles contain comparisons of modalities, and 2 articles discuss modally non-specific tasks. Preliminary findings from the systematic review indicate distinct functions of various frequency bands for working memory. Specifically, theta rhythms (4–8 Hz) in the frontal lobe were predominantly associated with information maintenance, while demonstrating a propension for increased synchronization during information processing. The alpha rhythm (8–14 Hz) was associated with inhibiting irrelevant data and protecting the current content of working memory, aligning with the widely accepted paradigm [5]. The beta rhythm (14–28 Hz) was most frequently noted to occur when maintaining and recalling information, and its power was associated with memory accuracy indicators. The gamma rhythm (28 Hz and higher) was seen during the process of encoding and maintaining information, and exhibited greater power for more complex stimuli. The analysis of connectivity revealed that encoding visual and verbal stimuli involves interhemispheric frontal-temporal and frontal-central connections that interact through theta rhythms. Additionally, storing information relies on the interplay of theta and gamma rhythms between the frontal and parietal networks. Notably, when dealing with verbal stimuli, the connectivity of the frontal and temporal brain lobes through theta rhythm enhances with load during storage. The alpha rhythm facilitates communication across posterior and frontal divisions during information storage, whereas beta rhythm is associated with frontal-temporal connections. During visual information storage, theta rhythm mediates communication across frontal-postcentral connections. As storage load increases, theta rhythm leads to strengthening of frontal-parietal and frontal-frontal connections until the threshold of working memory capacity is reached, after which these connections weaken. When processing information, connectivity of the right frontal-occipital network, right prefrontal and left occipital regions, right frontal and occipital-parietal areas for visual memory, and frontal-parietal regions for verbal memory were observed in the theta band. Connectivity of the occipital brain regions primarily occurred in the alpha spectrum, and temporal regions exhibited high frequencies. No specific differences were observed between the elderly and adults, aside from the suppression of low frequencies and the prevalence of high frequencies in the connectivity analysis.

The high pseudorapidity ($\eta$) region of the Compact Muon Solenoid (CMS) muon system is covered by Cathode Strip Chambers only and lacks redundant coverage despite the fact that it is a challenging region for muons in terms of backgrounds and momentum resolution. During the annual Year-End Technical Stops 2022 & 2023, two new layers of improved Resistive Plate Chambers (iRPC) will be added, RE3/1 & RE4/1, which will completely cover the region of $1.8 < |\eta| < 2.4$ in the endcap. Thus, the additional new chambers will lead to increase efficiency for both trigger and offline reconstruction in the difficult region where the background is the highest and the magnetic field is the lowest within the muon system. The extended RPC system will improve the performance and the robustness of the muon trigger. The final design of iRPC chambers and the concept to integrate and install them in the CMS muon system have been finalized. In this report, the main results demonstrating the implementation and installation of the new iRPC detectors in the CMS muon system at high $|\eta|$ region will be presented.

Abstract The paper concerns theoretical possibility of visiting orbital transport vehicles based on nuclear power unit and electric propulsion system on the Earth's orbit by astronauts to maintain work with payload from the perspective of radiation safety. There has been done estimation of possible time of the crew's staying in the area of payload of orbital transport vehicles for different reactor powers, which is a consistent part of nuclear power unit.

In the Endcap regions, CMS Muon spectrometer is using Cathode Strip Chambers (CSCs) as muon tracking and trigger detectors, also Resistive Plate Chambers (RPCs) serve as dedicated trigger detectors and improve the muon reconstruction by providing the excellent timing resolution for identification of muon particles. At the present, the four Endcap discs are not fully equipped: RPCs are covering only Endcap disks up to |ŋ| = 1.8. During the Long Shutdown 3 (from 2023 to 2026) of the Large Hadron Collider, Endcap stations 3 and 4 will be further instrumented with new improved RPCs (iRPCs) that will be covering the pseudorapidly region 1.8 < |ŋ| < 2.4, increasing the redundancy in this region. Nowadays, the final design of RPC chambers has been developed and the RPC double gap prototypes with a gas thickness 1.4mm are being tested. The performance and stability of iRPCs at the future HL-LHC upgrades have been studied (detection efficiency, cluster size, rate capability) at the Gamma-Irradiation Facility (GIF++) at CERN, where high energy charged particle beams (mainly muons) are combined with gammas from a 14 TBq 137Cesium source which simulates the background expected at the CMS experiments. In this paper, the main results obtained during the test at GIF ++ are presented.

In the next decades, the Large Hadron Collider (LHC) will run at very high luminosity (HL-LHC) 5×1034 cm−2s−1, factor five more than the nominal LHC luminosity. During this period the CMS RPC system will be subjected to high background rates which could affect the performance by inducing aging effects. A dedicated longevity program to qualify the present RPC system for the HL-LHC running period is ongoing. At the CERN Gamma Irradiation Facility (GIF++) four RPC detectors, from the spare production, are exposed to an intense gamma radiation for a dose equivalent to the one expected at the HL-LHC . The main detector parameters are under monitoring as a function of the integrated charge and the performance is studied with a muon beam. Preliminary results of the study after having collected ≈ 34% of the expected integrated charge will be presented.

The Resistive Plate Chambers (RPC) are used for muon triggers in the CMS experiment. To calibrate the high voltage working-points (WP) and identify degraded detectors due to radiation or chemical damage, a high voltage scan has been performed using 2017 data from pp collisions at a center-of-mass energy of 13 TeV. In this paper, we present the calibration method and the latest results obtained for the 2017 data. A comparison with all scans taken since 2011 is considered to investigate the stability of the detector performance in time.

The Muon Upgrade Phase II of the Compact Muon Solenoid (CMS) aims to guarantee the optimal conditions of the present system and extend the η coverage to ensure a reliable system for the High Luminosity Large Hadron Collider (HL-LHC) period. The Resistive Plate Chambers (RPCs) system will upgrade the off-detector electronics (called link system) of the chambers currently installed chambers and place improved RPCs (iRPCs) to cover the high pseudo−rapidity region, a challenging region for muon reconstruction in terms of background and momentum resolution. In order to find the best option for the iRPCs, an R&D program for new detectors was performed and real size prototypes have been tested in the Gamma Irradiation Facility (GIF++) at CERN. The results indicated that the technology suitable for the high background conditions is based on High Pressure Laminate (HPL) double-gap RPC. The RPC Upgrade Phase II program is planned to be ready after the Long Shutdown 3 (LS3).

The Muon Drift Tube (MDT) chambers provide very precise and reliable muon tracking and momentum measurement in the ATLAS muon spectrometer. Already in Run 2 of the LHC they have to cope with very high background counting rates up to $$500$$ Hz/cm $${}^{2}$$ in the inner endcap layers. At High-Luminosity LHC (HL-LHC), the background rates are expected to increase by almost a factor of 10. New small (15 mm)-diameter Muon Drift Tube (so-called sMDT) detectors have been developed for upgrades of the muon spectrometer. They provide an order of magnitude higher rate capability and allow for the installation of additional new triplet thin-gap RPC trigger chambers in the barrel inner layer of the muon detector for HL-LHC. They have been designed for mass production at the Max Planck Institute (MPI) for Physics in Munich and achieve a sense of wire positioning accuracy of 5 $$\mu$$ m. A pilot project for the barrel inner layer upgrade is underway during the 2019/2021 LHC shutdown. Several sMDT chambers have already been installed and operated in the ATLAS detector. The detailed studies of the muon detection efficiency and muon track resolution have been carried out after the assembling of the sMDT detectors in MPI and repeated at CERN after the integration with the new RPC detectors. The author will describe the detector design, the quality assurance and certification path, as well as will present the status of the installation and commissioning, worth its preliminary results and an overview for the complete integration of the sMDT project In the ATLAS experiment.

In the presented work the results of GRBs temporal profiles analysis in the high energy gamma-band are discussed. Now GRBs high energy gamma-emission was observed both during short and long bursts mostly by detectors onboard Fermi and Agile satellites. The duration of such emission is more than some hundreds seconds and sufficiently longer than t90 in the low energy band. But usually the maximum of high energy emission is in the t90 intervals. However the investigation of GRBs temporal profiles in the region E>100 MeV have shown the opportunity of new burst type separation. In the difference of usual GRBs, temporal profiles of new type of bursts in the high energy gamma-band have several characteristic features. For example, GRB090323, GRB090328 and GRB090626 temporal profiles have additional maxima after low energy t90 intervals finished. These bursts temporal profile analysis have shown that faint peaks in low energy bands close to the ends of low energy t90 intervals preceded these additional maxima. The analogues features were separated during some other GRBs by the results of preliminary data analysis, for example, GRB110721A and GRB100724B. We suppose that these GRBs could be considered as different GRB type. The temporal profiles and spectra characteristic properties of new type of bursts are discussed in this article.

Most part of gamma-ray bursts (GRBs) spectra are well described by Band model with following parameters: α, β (spectral indices in low and high energy bands) and Epeak (energy of spectral peak). For several GRB parameter β characterizing the spectral shape in the region up to some hundred MeV (for example, GRB100724B). Moreover, Band spectrum of GRB080916C covering 6 orders of magnitude. Until recently spectral hardness parameter H32 (the ratio of total counts in the 100 − 300 keV and 50 − 100 keV energy range) was used for additional classification events on hard and soft, for GRBs groups selection on hardness and duration distributions (subgroup of intermediate bursts) and so on. However, H32 is defined in energy intervals 50−100 keV and 100−300 keV, but for some GRB Epeak> 300 keV and this value is outside regions of H32 definition. Thus, parameter H32 is incompletely represents spectral properties of such events. Basing on Band model we introduce new integral criteria could be used in the wide energy band for data analysis in past experiments such as BATSE (0.02 − 2 MeV), COMPTEL (0.8 − 30 MeV); EGRET (20 MeV − 30 GeV); in now operated experiments Fermi (8 keV − 1MeV, 200 keV − 40 MeV and 300 MeV − 300 GeV), AGILE (18 − 60 keV and 30 MeV − 50 GeV) and in future experiments: GAMMA−400 (0.1 − 3000 GeV) and so on. In the present work spectral parameters taken from BATSE and from Fermi catalogues were analyzed and the new integral criteria were investigated. Results of data studying have shown that new criteria allow making GRB classification including intermediate bursts subgroup separation.

We measure the efficiency of CMS Resistive Plate Chamber (RPC) detectors in proton-proton collisions at the centre-of-mass energy of 13 TeV using the tag-and-probe method. A muon from a Z0 boson decay is selected as a probe of efficiency measurement, reconstructed using the CMS inner tracker and the rest of CMS muon systems. The overall efficiency of CMS RPC chambers during the 2016–2017 collision runs is measured to be more than 96% for the nominal RPC chambers.

Several theoretical models inspired by the idea of supersymmetry (SUSY) accommodate the possibility of Heavy Stable Charged Particles (HSCPs). The Phase II upgrade of the CMS-RPC system will allow the trigger and identification of this kind of particles exploiting the Time-of-Flight Technique with the improved time resolution that a new Data Acquisition System (DAQ) system will provide (∼2 ns). Moreover, new Resistive Plate Chambers (RPC) detector chambers will be installed to extend the acceptance coverage up to |η|<2.4 with similar time resolution and better spatial resolution. We present a trigger strategy to detect HSCPs with the RPC detectors. Its performance is studied with Monte Carlo simulations and the expected results with the High Luminosity Large Hadron Collider (HL-LHC) data are shown.

The Doctoral Thesis subject has been proposed by the CMS RPC Collaboration to demonstrate that iRPC technology is the most suitable choice for the upgrade of the Muon System. The next research activities have been conducted in this context: The first activity, conducted in the framework of the iRPC RE3/1 and RE4/1 chambers integration and installation in the innermost region of CMS Muon Spectrometer, is focused on survey measurements performed in order to determine the space actually available for future installations during the Yearly Technical Stops at the end of 2022 and 2023. Surface topology and geometry of the Yoke Endcap (YE) ±2 and YE±3 iron disks in the region 1.8<|eta|<2.4 have been studied in detail by using different methods such as photography, photogrammetry, theodolite and infrared proximity sensor. After analyzing the experimental data obtained during the survey measurements, I developed the very precise 3D-model of the mechanical simulation for the installation of the RE3/1 and RE4/1 detectors in the dedicated |eta| region. I designed the mechanical components to mount chambers here. These results of my work were reported in the CMS Muon Technical Design Report (TDR) which was submitted to the CMS Muon Committee on 12 September 2017. The second activity has been focused on the developing, commissioning and characterization of the iRPC RE3/1 and RE4/1 detector prototypes. By using the information obtained during the previous activity, in August 2017 at the CERN CMS-RPC QA/QC facility, I organized the development and assembly of the first two real-size RE3/1 and RE4/1 detector prototypes and studied their detection performance with the new version of the PETIROC ASIC Front-end electronics. I was the key person who participated in all production processes on the construction and testing the detecting elements, assembling of the new prototypes and subsequent testing them with the new electronics under muon beam at the CERN Gamma Irradiation Facility (GIF++) in August 2018. By using the unique test area of the CERN GIF++ facility, I studied the iRPC detector performances at the different background conditions which will be similar to the future CMS conditions during the HL-LHC program. By studying the rate capability of the real-size iRPC detector prototypes I have experimentally shown that the new iRPC technology can effectively operate in the harsh background CMS environmental and can fulfill all physics requirements of the CMS experiment. The third my activity included the testing of the new INFN Rome Front-end electronics together with iRPC detector prototype. The INFN Rome electronics has been proposed as a possible alternative to PETIROC ASIC electronics in time for the CMS-RPC system upgrade project, thus increasing the chance of success for the project. This has been the main strategy adopted by the CMS-RPC community and, consequently, it was necessary to find another available technology in order to develop the Front-end electronics to readout the iRPC detectors. In September 2018, I developed and assembled the second real-size iRPC RE4/1 detector prototype in the INFN Rome Tor Vergata laboratories (Italy) in order to study the performance with the INFN Rome Front-end boards. As in the previous research activity, I organized the subsequent testing of the iRPC detector prototype with the new electronics in the last available muon particle beam in the GIF++ facility at CERN before the starting of the Long Shutdown -2 period at LHC. In order to compare the results obtained from the first two RE3/1 and RE4/1 detector prototypes, I have studied the same number of chamber parameters of second iRPC RE4/1 detector prototype, such as a detection efficiency, cluster size, and rate capability. I experimental shown that this type of new Front-end board can be a great substitute for the PETIROC ASIC electronics. A majority of the results obtained during the last two years of Ph.D. contributed to the success of the iRPC project and its final approval by CMS Collaboration.

The High Luminosity LHC (HL-LHC) phase is designed to increase by an order of magnitude the amount of data to be collected by the LHC experiments. The foreseen gradual increase of the instantaneous luminosity of up to more than twice its nominal value of $10\times10^{34}\ {\rm cm}^{-1}{\rm s}^{-2}$ during Phase I and Phase II of the LHC running, presents special challenges for the experiments. The region with high pseudo rapidity ($\eta$) region of the forward muon spectrometer ($2.4 > |\eta| > 1.9$) is not equipped with RPC stations. The increase of the expected particles rate up to 2 kHz cm$^{-1}$ ( including a safety factor 3 ) motivates the installation of RPC chambers to guarantee redundancy with the CSC chambers already present. The current CMS RPC technology cannot sustain the expected background level. A new generation of Glass-RPC (GRPC) using low-resistivity glass was proposed to equip the two most far away of the four high $\eta$ muon stations of CMS. In their single-gap version they can stand rates of few kHz cm$^{-1}$. Their time precision of about 1 ns can allow to reduce the noise contribution leading to an improvement of the trigger rate. The proposed design for large size chambers is examined and some preliminary results obtained during beam tests at Gamma Irradiation Facility (GIF++) and Super Proton Synchrotron (SPS) at CERN are shown. They were performed to validate the capability of such detectors to support high irradiation environment with limited consequence on their efficiency.

Small-diameter Drift Tube (sMDT) detectors with 15 mm tube diameter have proven to be excellent candidates for precision muon tracking detectors in experiments at future hadron colliders like HL-LHC and FCC-hh where unprecedentedly high background rate capabilities are required. sMDT chambers are currently being installed in the inner barrel layer of the ATLAS muon spectrometer. The rate capability of the sMDT drift tubes in terms of muon detection efficiency and spatial resolution is limited by the performance of the readout electronics. A new (s)MDT ASD (Amplifier-Shaper-Discriminator) readout chip for use at the HL-LHC and future hadron colliders with a faster peaking time compared to the old chip has been developed, reducing the discriminator threshold crossing time jitter and thus improving the time- and spatial resolution with and without $\gamma$-background radiation. Additionally, a method compensating the gas gain drop due to space charge at high $\gamma$-background hit flux by adjusting the sMDT operating voltage will be presented. Simulations show, that the addition of active baseline restoration circuits in the front-end electronics chips in order to suppress signal-pile-up effects at high counting rates further leads to significant improvement of both efficiency and resolution. Extensive tests using sMDT test chambers have been performed at the CERN Gamma Irradiation Facility (GIF++). Chambers equipped with new readout chips with improved pulse shaping and discrete readout circuits with baseline restoring functionality have been tested.

The Monitored Drift Tubes, as a part of the ATLAS muon spectrometer, are precision drift chambers designed to provide excellent spatial resolution and high tracking efficiency independent of the track angle. Through the life of the LHC and ATLAS experiment, this detector has already demonstrated that they provide precise tracking over large areas. The aim of the ATLAS muon spectrometer upgrade is to increase the muon trigger efficiency, precise muon momentum measurement and to improve the rate capability of the muon system in the high-background regions during the High-Luminosity LHC runs. To meet these requirements, the proposed solution is based on the small (15 mm) diameter Muon Drift Tube chamber (sMDT) technology. The new detector provides about an order of magnitude higher rate capability and allows for the installation of additional new triplet Resistive Plate Chambers (RPCs) trigger detectors in the barrel inner layer of the muon system. A pilot project for the barrel inner layer upgrade is underway during the 2019/21 LHC shutdown. For this reason, the Max-Planck-Institute for Physics in Munich has built 16 sMDT chambers, each will cover an area of about 2.5 $m^{2}$. To ensure their proper operation in the experiment, the sMDT detectors have to pass a set of stringent tests both at the production site and after their delivery at CERN. After their installation in the ATLAS muon spectrometer, the muon stations are further tested and commissioned with cosmic rays. The author will describe the detector design, the quality assurance and certification path, as well as will present the experience with the chamber tests, the integration procedure and installation of the muon stations in the ATLAS experiment.

The Monitored Drift Tubes, as a part of the ATLAS muon spectrometer, are precision drift chambers designed to provide excellent spatial resolution and high tracking efficiency independent of the track angle. Through the life of the LHC and ATLAS experiment, this detector has already demonstrated that they provide precise tracking over large areas. The aim of the ATLAS muon spectrometer upgrade is to increase the muon trigger efficiency, precise muon momentum measurement and to improve the rate capability of the muon system in the high-background regions during the High-Luminosity LHC runs. To meet these requirements, the proposed solution is based on the small (15 mm) diameter Muon Drift Tube chamber (sMDT) technology. The new detector provides about an order of magnitude higher rate capability and allows for the installation of additional new triplet Resistive Plate Chambers (RPCs) trigger detectors in the barrel inner layer of the muon system. A pilot project for the barrel inner layer upgrade is underway during the 2019/21 LHC shutdown. For this reason, the Max-Planck-Institut für Physik in Munich has built 16 sMDT chambers, each will cover an area of about 2.5 m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . To ensure their proper operation in the experiment, the sMDT detectors have to pass a set of stringent tests both at the production site and after their delivery at CERN. After their installation in the ATLAS muon spectrometer, the muon stations are further tested and commissioned with cosmic rays. The author will describe the detector design, the quality assurance and certification path, as well as will present the experience with the chamber tests, the integration procedure and installation of the muon stations in the ATLAS experiment.