8 research outputs found

    Effect of rice husk ash addition on the physical properties of soda-lime-silica glass for building glass and window

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    One of the promising raw materials in producing glass is rice husk (RH), which contains about 90% of silica and is usually burnt in an open area which contributed to serious air pollution problems. The environmental issues of RH could be resolved by utilizing rice husk ash (RHA) as a silica source in the glass manufacturing process. The main objective of this research is to develop an ecofriendly Soda-Lime-Silica - Rice Husk Ash (SLS-RHA) glass for the application of building glass and window. Three main experiments were conducted; morphology test, ultrasonic velocities testing and Rockwell hardness test to assess the microstructure, elastic and mechanical behaviour of the developed SLS-RHA glass. Response surface methodology (RSM) was used to design the experiments incorporating two factors; such as the ratio of SLS to RHA and their interrelationship; and the effect on glass hardness properties were analysed using analysis of variance (ANOVA). From the morphology analysis, the addition of RHA to the glass former matrix increased the porosity of the glass which influenced the elastic properties of the newly developed glass. It was observed that sample two with 5% RHA wt. addition performed the finest under elastic properties test and the longitudinal and shear modulus of RHA glass decrease with the increased of RHA content. Sample with 5% of RHA possessed high and medium elastic properties, which make it easier to bend rather than elongate, less stiff, tough at a certain direction, and has low rigidity. The value of the longitudinal modulus decreased 7.12% with the addition of 10% RHA wt. Finally, for the hardness test, based on the observation from HRF, HRB and HRG contour plots which showed that the hardness values for each sample decreased as the RHA percentage increased in the SLS glass system. The hardness of the glass decreased with an increase in the addition of RHA content due to elastic deformation. The optimal solution obtained from ANOVA for the combination of RHA and SLS is SLS (A) 29.589% wt. and RHA (B) 0.031% wt. This formulation provided the results of 130.588 for HRF, 124.844 for HRB and 120.098 for HRG. It can be summarized that the use of silica from RHA efficiently improved the bulk modulus while maintaining a lower Young’s modulus value of the glass. This resulted in improved impact resistance of the glass due to a slower decelerated in smaller stress acting on the glass even though the glasses are less stiff. In this research, RHA proved to be a good silica source alternative for the glass manufacturing process, which can potentially improve the melting process temperature indirectly helps to reduce the cost of the manufacturing process

    Evaluation of the effects of soda-lime-silica glass with rice husk ash as an additive on the hardness behavior

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    Demand for eco-friendly materials increases each year due to their excellent properties, which has proved to contribute to developing a sustainable environment. One of the promising raw materials in producing Glass is rice husk, a waste product from paddy harvesting, containing about 90% of silica. Rice husks are usually burnt in an open area and contribute to severe air pollution problems. In this research, Soda-Lime-Silica Rice Husk Ash (SLRHA) glass which is a new combination of soda-lime silicate (SLS) glass and rice husk ash (RHA), was developed for building glass and window application. The hardness properties of the developed SLS-RHA glass system are presented in this paper. These glasses were investigated to determine the effect of RHA addition on the physical properties of SLS glass. The experimental works using RSM have successfully identified the significant factors and optimized the responses. Based on the Rockwell hardness test, the outcomes demonstrated that the glass sample contained 29.84% weight SLS and 0.06% weight RHA. The result indicated that crack propagation was increased with the increasing addition of RHA, which causes an increase in cracks and voids due to the creation of more debonding

    CMS - The Compact Muon Solenoid

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    CMS is a general purpose proton-proton detector designed to run at the highest luminosity at the LHC. It is also well adapted for studies at the initially lower luminosities. The CMS Collaboration consists of over 1800 scientists and engineers from 151 institutes in 31 countries. The main design goals of CMS are: \begin{enumerate} \item a highly performant muon system, \item the best possible electromagnetic calorimeter \item high quality central tracking \item hermetic calorimetry \item a detector costing less than 475 MCHF. \end{enumerate} All detector sub-systems have started construction. Engineering Design Reviews of parts of these sub-systems have been successfully carried-out. These are held prior to granting authorization for purchase. The schedule for the LHC machine and the experiments has been revised and CMS will be ready for first collisions now expected in April 2006. \\\\ ~~~~\bullet Magnet \\ The detector (see Figure) will be built around a long (13~m) and large bore (ϕ\phi=5.9~m) high-field (4T) superconducting solenoid leading to a compact design for the muon spectrometer. The magnetic flux is returned through \approx1.5~m of saturated iron yoke (1.8~T) instrumented with muon chambers. The construction of the magnet is well advanced. It will be tested on the surface in July 2004. Three of the five barrel yokes (YB) have been assembled in the surface building at Point 5. The assembly of the endcap yokes (YB) will start in April 2001. Four good lengths of Rutherford cable and three lengths of the insert (Rutherford cable co-extruded with pure aluminium), out of 21, have been produced. Each one has a length of 2.65km. The contracts for the winding machine have been placed. \\\\ ~~~~\bullet Inner Tracking \\ All high ptp_t muons, isolated electrons and charged hadrons, produced in the central rapidity region, are reconstructed with a momentum precision of Δpt/pt\Delta p_t / p_t \approx~0.005~+~0.15ptp_t (ptp_t in TeV). The high momentum precision is a direct consequence of the high magnetic field. The tracking volume is given by a cylinder of length 6~m and a diameter of 2.6~m. In order to deal with high track multiplicities tracking detectors with small cell sizes are used. Silicon microstrip detectors provide the required granularity and precision in the bulk of the tracking volume. Stereo information is provided by back-to-back microstrip detectors with strips at a small angle. Pixel detectors placed close to the interaction region improve the measurement of the track impact parameter and secondary vertices. High track finding efficiencies are achieved for isolated high ptp_t tracks. It is also fairly high for tracks in jets. \\ In June 2000 the LHCC approved the `All-Silicon Tracker' to be built in a single stage. The layout has been optimized with the removal of the central support tube. A pre-production comprising 200 detectors has been launched to exercise the automated production procedure. \\ The short bunch crossing time at the LHC (25ns) places challenging requirements on the readout electronics. Furthermore, the detectors and the read-out electronics have to withstand high levels of irradiation. A test in an LHC-like bunched beam was successfully carried out to test the functionality of the full electronics chain. Beam tests using electronics designed in the 0.25μ\mum technology have confirmed the expected performance. \\ Good progress is also being made on the electronics and mechanics of the pixel detectors. \\\\ ~~~~\bullet Muon System \\ Centrally produced muons are measured three times, in the inner tracker, after the coil and in the return flux. They are then identified and measured in four identical muon stations (MB) inserted in the return yoke. Special care has been taken to avoid pointing cracks and to maximize the geometric acceptance. Each muon station consists of twelve planes of aluminium drift tubes designed to give a muon vector in space, with 100~μ\mum precision in position and better than 1~mrad in direction. The four muon stations include RPC triggering planes that also identify the bunch crossing and enable a cut on the muon transverse momentum at the first trigger level. The endcap muon system also consists of four muon stations (ME). Each station consists of six planes of Cathode Strip Chambers. The chambers are arranged such that all muon tracks traverse four stations at all rapidities, including the transition region between the barrel and the endcaps. The last muon stations are after a total of \geq~20λ\lambda of absorber so that only muons can reach them. The four muon stations lead to a redundant and robust muon system. \\ Facilities for mass production have been set up in the institutes participating in the construction of the muon chambers. One site, CIEMAT (Madrid), has built two pre-production drift tube prototype chambers using the final assembly tools and procedures. The commissioning of two more sites (Aachen and Legnaro, Padova) is nearly complete. Around thirty CSC chambers have been manufactured at Fermilab. Parts and tooling have been procured for the sites at PNPI, St. Petersburg and IHEP, Beijing. The procurement of parts for the barrel RPCs also commenced in 2000. Mass production of DTs and CSCs at various sites is expected to reach the final rates in 2001. \\ The combined (using the inner tracker as well as the muon chambers) muon momentum resolution is better than 5\% at 0.3 TeV in the central rapidity region η<|\eta| < 2, and \approx 10\% for ptp_t = 2 TeV. Low-momentum (pt<p_t < 100 GeV) muons are measured before the absorber with a precision of about 1.5\% up to a pseudorapidity of 2. \\\\ ~~~~\bullet Calorimetry \\ The coil radius is large enough to install essentially all the calorimetry inside and hence avoid the coil-electromagnetic calorimeter interference. A high precision electromagnetic calorimeter (ECAL) using lead tungstate (PbWO4_4) crystals has been chosen. Lead tungstate is a dense and relatively easy crystal to grow. \\ The scintillation light is detected by silicon avalanche photodiodes in the barrel region (EB, η<|\eta|<1.48) and vacuum phototriodes in the endcap region (EE, 1.48<η<<|\eta|<3.0). The expected energy resolution is better than 0.6\% for electrons and photons with energies greater than 75 GeV. A preshower system (SE) is installed in front of the endcap calorimeter (1.65 η\leq|\eta|\leq 2.6). \\ The ECAL is followed by a copper/scintillator sampling hadronic calorimeter (HB, HE). The light is channelled by clear fibres fused to wave-length shifting fibres embedded in scintillator plates. The light is detected by photodetectors that can provide gain and operate in high axial magnetic fields (proximity focussed hybrid photodiodes). Coverage up to rapidities of 5.0 is provided by a steel/quartz fibre calorimeter (HF). The Cerenkov light emitted in the quartz fibres is detected by photomultipliers. \\ The pre-production (6000) of crystals from Russia has been completed. A contract for a further 30000 crystals has been placed in Russia. A breakthrough in crystal growing in Russia means that ingots can be grown of a diameter large enough for two crystals to be cut out. This will considerably increase the yield of crystals per oven. The crystal producers in China, using 28-fold pulling furnaces, have delivered 100 preliminary pre-production crystals that are being evaluated. The contract for the remaining 40000 crystals should be placed in 2001. The infrastructure at the centres where the crystals will be assembled into modules for installation has been set up. The photo-detectors, meeting the specifications, have been developed in collaboration with industry. The front-end chain consists of a preamplifier/range selector (FPPA), an ADC and a serializer/optical link. A 0.25μ\mum technology version of the serializer has been chosen. \\ Photon-pizero separation in the forward region requires a preshower detector (SE) in front of the crystals. Silicon sensors for the pre-shower detector, of the required quality, have now been produced in Russia, Taiwan and India. A large dynamic range preamplifier in a radiation-hard technology has been fabricated and successfully tested. \\ The absorber for the first HCAL half-barrel, HB-1 (18 wedges), was trial-assembled at Felguera, Spain. It was dismantled and the wedges have been delivered to CERN. The optics, scintillator plus embedded fibres, for more than half the barrel wedges have also been manufactured and delivered to CERN. The trial assembly of one endcap is nearing completion at the manufacturer, MZOR (Byelorussia). Optics manufacture for HE has started. The HF design was changed from bricks to 18 wedges per side. The fibre spacing was changed from 2.5mm to 5mm but the packing fraction is preserved. \\\\ ~~~~\bullet Trigger and Data Acquisition \\ The trigger and data acquisition consists of four parts: the front-end detector electronics, the calorimeter and muon first level trigger processors, the readout network and an on-line event filter system. The first two parts are synchronous and pipelined with a pipeline depth corresponding to \approx3~μ\mus. The latter two are asynchronous and based on industry standard data communication components and commercial PCs. The resources that would have been required for a hardware second level trigger processors are invested in a high bandwidth (\approx~500~Gbit/s) readout network and in the event filter processing power (106^{6}-107^{7} MIPs), both of which are more suitable for upgrading as commercially available technology develops. \\ The CMS Level-1 trigger decision is based upon the presence of physics objects such as muons, photons, electrons, and jets, as well as global sums of Et_t and missing Et_t (to find neutrinos). The Level-1 Trigger Technical Design Report was submitted at the end of 2000. The DAQ system has to assemble the data from the triggered event, contained in about 500 front-end buffers (readout units), into a single processor in a ``farm'' for executing physics algorithms so that the input rate of 100 kHz is reduced to the 100 Hz of sustainable physics. A new Event Builder setup has been installed that consists of 64 Intel-PCs interconnected by two networks based on the most advanced technologies: a 64 port Gbit Ethernet (Foundry) and a 128-port Myrinet switch (Myricom). The setup will be used to evaluate all the software and hardware design options that will be considered for the TDR, destined for end-2002. \\\\ ~~~~\bullet Computing and Core Software \\ For complex systems, such as the CMS detector, an `object oriented' approach, implemented in C++, is now the choice of software developers. The move to this mainstream software technology will help to manage the process of change over the long lifetime of the experiment. C++ releases have been made of the functional prototypes of the software comprising the framework (CARF), the reconstruction program (ORCA), a basic GEANT4-based simulation program (OSCAR), and an interactive graphics toolkit (IGUANA). The OO technology has been used in the production of Level-1 and High Level Trigger simulation data. ORCA has been used for detector, trigger and physics studies. \\ The data storage, networking and processing power needed to analyse CMS data is well in excess of those of today's facilities. Technological advances will help to make the data analysis possible in a distributed environment, where physicists are scattered all over the world. The optimum mix of storage, networking and processing will change as technology develops. A multi-Tier model, similar to that developed by the MONARC project, underpinned by Grid Technology to provide efficient resource utilization and rapid turnaround time will be prototyped. \\\\ ~~~~\bullet Physics Reconstruction and Selection \\ With the construction phase starting in earnest, physics simulation work has begun to focus on the development of the eventual reconstruction code. As mentioned above this development is taking place using C++ and object-oriented methods. CMS has decided that the first priority is a full understanding and verification of the Higher Level Triggers (HLT). Since CMS does not employ distinct physical intelligences for the would-be Level-2 and Level-3 triggers, but only a single processor farm, the task of selecting events is intimately linked with that of reconstructing the associated detector information online. With this in mind, four ``Physics Reconstruction and Selection'' (PRS) groups were started (electron/photon, muon, jet/missing Et_t, and b/τ\tau vertexing) in April 1999. The aim of the groups is to develop the reconstruction and selection procedures (algorithms and software) starting from the output of the Level-1 trigger, and aiming ultimately at the full off-line reconstruction. During 2000, the four groups delivered the first algorithms that correspond to a reduction of the event rate after Level-1 by about a factor 10 using information from single CMS sub-detectors. The activity now continues as a new CMS project, the PRS project, which has close ties with the Computing and Trigger/DAQ projects. The PRS groups are now working on reconstructing physics objects using information from multiple CMS sub-detectors. \\\\ ~~~~\bullet Physics Performance \\ Although high luminosity is essential to cover the entire range of mechanisms of electroweak symmetry-breaking, the LHC machine will start at significantly lower luminosities (L~\leq1033^{33} cm2^{-2} s1^{-1}). The pixel detectors and the PbWO4_4 crystal electromagnetic calorimeter considerably enhance the discovery potential of CMS at low luminosities. \\ A Standard Model (SM) Higgs boson with mass between 95 and 150~GeV would be discovered via its two photon decay after an integrated luminosity of about 3×\times104^4 pb1^{-1}. The same integrated luminosity gives a discovery range covering masses from 135 to 525~GeV in the four lepton (e or μ\mu) channel, with only a small gap in the coverage around 2 mW_W. An integrated luminosity of 105^5 pb1^{-1} (taken at 1034^{34} cm2 ^{-2}s1^{-1} ) would allow discovery via these channels over the full range between 85 and 700 GeV. Tagging the events produced by WW- and ZZ-fusion by detecting characteristic forward jets, and using decay modes with larger branching ratios (H \rightarrow WW \rightarrow lν\nujj, and H~\rightarrow ZZ \rightarrow lljj), should allow the discovery range for a SM Higgs boson to be extended up to 1~TeV for the same integrated luminosity. \\ The two photon and four lepton channels are also crucial for the discovery of a Higgs boson in the Minimal Supersymmetric Standard Model (MSSM). Various channels involving the tau lepton (h0^0, H 0^0, A 0^0 \rightarrow τ\tau τ\tau, H±^\pm \rightarrow τ\tau ν\nu) help to cover much of the remaining allowed (mA _{A}, tan β\beta) parameter space. Precise impact parameter measurements using the pixel detector play an important role here. \\ Many physics studies have been carried out in the context of supergravity models (SUGRA). A many-point scan of the gaugino / scalar mass parameter space has been conducted. Squarks and gluinos weighing up to 2~TeV can be detected using, as signature, events with one or more charged leptons, missing transverse energy and two or more jets. Sleptons weighing as much as 400~GeV can be found by looking for events without hadronic jets, but with lepton pairs and missing transverse energy with distinctive kinematic characteristics. Three-lepton states are particularly promising for the detection of charginos and neutralinos. In many cascade decays a heavier neutralino is produced that subsequently decays into the lightest one with the emission of a pair of charged leptons. For low to moderate values of tanβ\beta the spectrum of the di-lepton invariant masses shows a strikingly sharp end-point determined by the difference in neutralino masses. This feature can be used to select and almost fully reconstruct some events yielding e.g. the mass of the bottom squark. \\ The above studies of specific SUSY models indicate that it is possible to detect and measure a large fraction of the expected SUSY spectrum in CMS. Within the SUGRA models it should be possible to determine the fundamental parameters at the GUT scale. \\ The copious production of B mesons at LHC opens the way for significant measurements of CP violation effects in the B system. Using the Bs0^0_s and Bd0^0_d channels two of the angles in the unitarity triangle can be measured. Furthermore, by observing the time development of Bs0^0_s oscillations, the mixing parameter xs_s can be measured. \\ In addition to running as a proton-proton collider, LHC will be used to collide heavy ions at a centre of mass energy of 5.5~TeV per nucleon pair. A new form of deconfined hadronic matter, the quark-gluon plasma (QGP), should be formed at the resulting high energy densities (4-8 GeV/fm3^3). The formation of quark-gluon plasma in the heavy ion collisions is predicted to be signalled by a strong suppression of Υ\Upsilon' and Υ\Upsilon'' production relative to Υ\Upsilon production when compared to pp collisions. The CMS detector is well suited to detect low momentum muons and reconstruct the Υ\Upsilon, Υ\Upsilon' and Υ\Upsilon'' mesons produced. The good mass resolution (σ\sigma=37 MeV at Υ\Upsilon mass), afforded by the 4T field, enables the measurement of the suppression. Work has been carried out to obtain detailed understanding of the capabilities of CMS for heavy ion physics especially for signatures involving dimuon production, jet quenching and Z production. A detailed document has been prepared outlining the capabilities of CMS

    Observation of double J/ψ\psi meson production in pPb collisions at sNN\sqrt{s_\mathrm{NN}} = 8.16 TeV

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    International audienceThe first observation of the concurrent production of two J/ψ\psi mesons in proton-nucleus collisions is presented. The analysis is based on a proton-lead (pPb) data sample recorded at a nucleon-nucleon center-of-mass energy of 8.16 TeV by the CMS experiment at the CERN LHC and corresponding to an integrated luminosity of 174.6 nb1^{-1}. The two J/ψ\psi mesons are reconstructed in their μ+μ\mu^+\mu^- decay channels with transverse momenta pTp_\mathrm{T}>\gt 6.5 GeV and rapidity y\lvert y \rvert<\lt 2.4. Events where one of the J/ψ\psi mesons is reconstructed in the dielectron channel are also considered in the search. The pPb \to J/ψ\psiJ/ψ\psi+X process is observed with a significance of 5.3 standard deviations. The measured inclusive fiducial cross section, using the four-muon channel alone, is σ\sigma(pPb\to J/ψ\psiJ/ψ\psi+X)= 22.0 ±\pm 8.9 (stat) ±\pm 1.5 (syst) nb. A fit of the data to the expected rapidity separation for pairs of J/ψ\psi mesons produced in single (SPS) and double (DPS) parton scatterings yields σSPSpPbJ/ψJ/ψ+X\sigma^{\mathrm{pPb}\to\mathrm{J}/\psi\mathrm{J}/\psi+\mathrm{X}}_\text{SPS} = 16.5 ±\pm 10.8 (stat) ±\pm 0.1 (syst) nb and σDPSpPbJ/ψJ/ψ+X\sigma^{\mathrm{pPb}\to \mathrm{J}/\psi\mathrm{J}/\psi+\mathrm{X}}_\text{DPS} = 5.4 ±\pm 6.2 (stat) ±\pm 0.4 (syst) nb, respectively. This latter result can be transformed into a lower bound on the effective DPS cross section, closely related to the squared average interparton transverse separation in the collision, of σeff\sigma_\text{eff}>\gt 1.0 mb at 95% confidence level

    Measurement of the polarizations of prompt and non-prompt J/ψ\psi and ψ\psi(2S) mesons produced in pp collisions at s\sqrt{s} = 13 TeV

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    International audienceThe polarizations of prompt and non-prompt J/ψ/\psi and ψ\psi(2S) mesons are measured in proton-proton collisions at s\sqrt{s} = 13 TeV, using data samples collected by the CMS experiment in 2017 and 2018, corresponding to a total integrated luminosity of 103.3 fb1^{-1}. Based on the analysis of the dimuon decay angular distributions in the helicity frame, the polar anisotropy, λθ\lambda_\theta, is measured as a function of the transverse momentum, pTp_\mathrm{T}, of the charmonium states, in the 25-120 and 20-100 GeV ranges for the J/ψ/\psi and ψ\psi(2S), respectively. The non-prompt polarizations agree with predictions based on the hypothesis that, for pTp_\mathrm{T}\gtrsim 25 GeV, the non-prompt J/ψ/\psi and ψ\psi(2S) are predominantly produced in two-body B meson decays. The prompt results clearly exclude strong transverse polarizations, even for pTp_\mathrm{T} exceeding 30 times the J/ψ/\psi mass, where λθ\lambda_\theta tends to an asymptotic value around 0.3. Taken together with previous measurements, by CMS and LHCb at s\sqrt{s} = 7 TeV, the prompt polarizations show a significant variation with pTp_\mathrm{T}, at low pTp_\mathrm{T}

    Measurement of the ttˉ\mathrm{t\bar{t}}H and tH production rates in the H \tobbˉ\mathrm{b\bar{b}} decay channel using proton-proton collision data at s\sqrt{s} = 13 TeV

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    International audienceAn analysis of the production of a Higgs boson (H) in association with a top quark-antiquark pair (ttˉ\mathrm{t\bar{t}}H) or a single top quark (tH) is presented. The Higgs boson decay into a bottom quark-antiquark pair (H \tobbˉ\mathrm{b\bar{b}}) is targeted, and three different final states of the top quark decays are considered, defined by the number of leptons (electrons or muons) in the event. The analysis utilises proton-proton collision data collected at the CERN LHC with the CMS experiment at s\sqrt{s} = 13 TeV in 2016-2018, which correspond to an integrated luminosity of 138 fb1^{-1}. The observed ttˉ\mathrm{t\bar{t}}H production rate relative to the standard model expectation is 0.33 ±\pm 0.26 = 0.33 ±\pm 0.17 (stat) ±\pm 0.21 (syst). Additionally, the ttˉ\mathrm{t\bar{t}}H production rate is determined in intervals of Higgs boson transverse momentum. An upper limit at 95% confidence level is set on the tH production rate of 14.6 times the standard model prediction, with an expectation of 19.36.0+9.2^{+9.2}_{-6.0}. Finally, constraints are derived on the strength and structure of the coupling between the Higgs boson and the top quark from simultaneous extraction of the ttˉ\mathrm{t\bar{t}}H and tH production rates, and the results are combined with those obtained in other Higgs boson decay channels

    Measurement of the Bs0^0_\mathrm{s}\to J/ψ\psiKS0^0_\mathrm{S} effective lifetime from proton-proton collisions at s\sqrt{s} = 13 TeV

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    International audienceThe effective lifetime of the Bs0^0_\mathrm{s} meson in the decay Bs0^0_\mathrm{s}\to J/ψ\psiKS0^0_\mathrm{S} is measured using data collected during 2016-2018 with the CMS detector in s\sqrt{s} = 13 TeV proton-proton collisions at the LHC, corresponding to an integrated luminosity of 140 fb1^{-1}. The effective lifetime is determined by performing a two-dimensional unbinned maximum likelihood fit to the Bs0^0_\mathrm{s} meson invariant mass and proper decay time distributions. The resulting value of 1.59 ±\pm 0.07 (stat) ±\pm 0.03 (syst) ps is the most precise measurement to date and is in good agreement with the expected value

    Model-independent search for pair production of new bosons decaying into muons in proton-proton collisions at s\sqrt{s} = 13 TeV

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    International audienceThe results of a model-independent search for the pair production of new bosons within a mass range of 0.21 <\ltmm<\lt 60 GeV, are presented. This study utilizes events with a four-muon final state. We use two data sets, comprising 41.5 fb1^{-1} and 59.7 fb1^{-1} of proton-proton collisions at s\sqrt{s} = 13 TeV, recorded in 2017 and 2018 by the CMS experiment at the CERN LHC. The study of the 2018 data set includes a search for displaced signatures of a new boson within the proper decay length range of 0 <\ltcτc\tau<\lt 100 μ\mum. Our results are combined with a previous CMS result, based on 35.9 fb1^{-1} of proton-proton collisions at s\sqrt{s} = 13 TeV collected in 2016. No significant deviation from the expected background is observed. Results are presented in terms of a model-independent upper limit on the product of cross section, branching fraction, and acceptance. The findings are interpreted across various benchmark models, such as an axion-like particle model, a vector portal model, the next-to-minimal supersymmetric standard model, and a dark supersymmetric scenario, including those predicting a non-negligible proper decay length of the new boson. In all considered scenarios, substantial portions of the parameter space are excluded, expanding upon prior results
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