A Large Ion Collider Experiment (ALICE) has been conceived and constructed as a heavy-ion experiment at the LHC. During LHC Runs 1 and 2, it has produced a wide range of physics results using all collision systems available at the LHC. In order to best exploit new physics opportunities opening up with the upgraded LHC and new detector technologies, the experiment has undergone a major upgrade during the LHC Long Shutdown 2 (2019–2022). This comprises the move to continuous readout, the complete overhaul of core detectors, as well as a new online event processing farm with a redesigned online-offline software framework. These improvements will allow to record Pb-Pb collisions at rates up to 50 kHz, while ensuring sensitivity for signals without a triggerable signature.
High-luminosity particle collider experiments such as the ones planned at the High-Luminosity Large Hadron Collider require ever-greater vertexing precision of the tracking detectors, necessitating reductions in the material budget of the detectors. Traditionally, the fractional radiation length (x/X-0) of detectors is either estimated using known properties of the constituent materials, or measured in dedicated runs of the final detector. In this paper, we present a method of direct measurement of the material budget of a CMS prototype module designed for the Phase-2 upgrade of the CMS detector using a 40-65 MeV positron beam. A total of 630 million events were collected at the Paul Scherrer Institut PiE1 experimental area using a three-plane telescope consisting of the prototype module as the central plane, surrounded by two MALTA monolithic pixel detectors. Fractional radiation lengths were extracted from scattering angle distributions using the Highland approximation for multiple scattering. A statistical technique recovered runs suffering from trigger desynchronisation, and several corrections were introduced to compensate for local inefficiencies related to geometric and beam shape constraints. Two regions of the module were surveyed and yielded average x/X-0 values of (0.72 +/- 0.05)% and (0.95 +/- 0.09)%, which are compatible with empirical estimates for these regions computed from known material properties of 0.753% and 0.892%, respectively. Two types of higher-granularity maps of the fractional radiation length were produced, subdivided either into rectangular regions of uniform size, or polygonal-shaped regions of uniform material composition. The results bode well for the CMS Phase-2 upgrade modules, which will play a key role in the minimisation of the material of the upgraded detector.
In this paper we report the detection of five strong gamma-ray bursts (GRBs) by the High-Energy Particle Detector (HEPD-01) mounted on board the China Seismo-Electromagnetic Satellite, operational since 2018 on a Sun-synchronous polar orbit at a ∼507 km altitude and 97° inclination. HEPD-01 was designed to detect high-energy electrons in the energy range 3–100 MeV, protons in the range 30–300 MeV, and light nuclei in the range 30–300 MeV n −1 . Nonetheless, Monte Carlo simulations have shown HEPD-01 is sensitive to gamma-ray photons in the energy range 300 keV–50 MeV, even if with a moderate effective area above ∼5 MeV. A dedicated time correlation analysis between GRBs reported in literature and signals from a set of HEPD-01 trigger configuration masks has confirmed the anticipated detector sensitivity to high-energy photons. A comparison between the simultaneous time profiles of HEPD-01 electron fluxes and photons from GRB190114C, GRB190305A, GRB190928A, GRB200826B, and GRB211211A has shown a remarkable similarity, in spite of the different energy ranges. The high-energy response, with peak sensitivity at about 2 MeV, and moderate effective area of the detector in the actual flight configuration explain why these five GRBs, characterized by a fluence above ∼3 × 10 −5 erg cm −2 in the energy interval 300 keV–50 MeV, have been detected.
The Large Hadron Collider at CERN will undergo an upgrade in order to increase its luminosity to 7.5 × 10 34 cm -2 s -1 . The increased luminosity during this High-Luminosity running phase, starting around 2029, means a higher rate of proton-proton interactions, hence a larger ionizing dose and particle fluence for the detectors. The current tracking system of the CMS experiment will be fully replaced in order to cope with the new operating conditions. Prototype planar pixel sensors for the CMS Inner Tracker with square 50 μm × 50 μm and rectangular 100 μm × 25 μm pixels read out by the RD53A chip were characterized in the lab and at the DESY-II testbeam facility in order to identify designs that meet the requirements of CMS during the High-Luminosity running phase. A spatial resolution of approximately 3.4 μm (2 μm) is obtained using the modules with 50 μm × 50 μm (100 μm × 25 μm) pixels at the optimal angle of incidence before irradiation. After irradiation to a 1 MeV neutron equivalent fluence of Φ eq = 5.3 × 10 15 cm -2 , a resolution of 9.4 μm is achieved at a bias voltage of 800 V using a module with 50 μm × 50 μm pixel size. All modules retain a hit efficiency in excess of 99% after irradiation to fluences up to 2.1 × 10 16 cm -2 . Further studies of the electrical properties of the modules, especially crosstalk, are also presented in this paper.
High-energy, long gamma-ray bursts (GRBs) can be generated by the core collapse of massive stars at the end of their lives. When they happen in the close-by universe they can be exceptionally bright, as seen from the Earth in the case of the recent, giant, long-lasting GRB221009A. GRB221009A was produced by a collapsing star with a redshift of 0.152: this event was observed by many gamma-ray space experiments, which also detected an extraordinary long gamma-ray afterglow. The exceptionally large fluence of the prompt emission of about 0.013 erg cm −2 illuminated a large geographical region centered on India and including Europe and Asia. We report in this paper the observation of sudden electron flux changes correlated with GRB221009A and measured by the HEPP-L charged particle detector on board the China Seismo-Electromagnetic Satellite, which was orbiting over Europe at the time of the GRB event. The time structure of the observed electron flux closely matches the very distinctive time dependence of the photon flux associated with the main part of the emission at around 13:20 UTC on 2022 October 9. To test the origin of these signals, we set up a simplified simulation of one HEPP-L subdetector: the results of this analysis suggest that the signals observed are mostly due to electrons created within the aluminum collimator surrounding the silicon detector, providing real-time monitoring of the very intense photon fluxes. We discuss the implications of this observation for existing and forthcoming particle detectors on low Earth orbits.
The Large Hadron Collider (LHC) at CERN will undergo major upgrades to increase the instantaneous luminosity up to 5–7.5×10 34 cm -2 s -1 . This High Luminosity upgrade of the LHC (HL-LHC) will deliver a total of 3000–4000 fb -1 of proton-proton collisions at a center-of-mass energy of 13–14 TeV. To cope with these challenging environmental conditions, the strip tracker of the CMS experiment will be upgraded using modules with two closely-spaced silicon sensors to provide information to include tracking in the Level-1 trigger selection. This paper describes the performance, in a test beam experiment, of the first prototype module based on the final version of the CMS Binary Chip front-end ASIC before and after the module was irradiated with neutrons. Results demonstrate that the prototype module satisfies the requirements, providing efficient tracking information, after being irradiated with a total fluence comparable to the one expected through the lifetime of the experiment.
Time-dependent energy spectra of galactic cosmic rays (GCRs) carry crucial information regarding their origin and propagation throughout the interstellar environment. When observed at the Earth, after traversing the interplanetary medium, such spectra are heavily affected by the solar wind and the embedded solar magnetic field permeating the inner sectors of the heliosphere. The activity of the Sun changes significantly over an 11 yr solar cycle—and so does the effect on cosmic particles; this translates into a phenomenon called solar modulation. Moreover, GCR spectra during different epochs of solar activity provide invaluable information for a complete understanding of the plethora of mechanisms taking place in various layers of the Sun’s atmosphere and how they evolve over time. The High-Energy Particle Detector (HEPD-01) has been continuously collecting data since 2018 August, during the quiet phase between solar cycles 24 and 25; the activity of the Sun is slowly but steadily rising and is expected to peak around 2025/2026. In this paper, we present the first spectra for ∼50–250 MeV galactic protons measured by the HEPD-01 instrument—placed on board the CSES-01 satellite—from 2018 August to 2022 March over a one-Carrington-rotation time basis. Such data are compared to the ones from other spaceborne experiments, present (e.g., EPHIN, Parker Solar Probe) and past (PAMELA), and to a state-of-the-art three-dimensional model describing the GCRs propagation through the heliosphere.
To cope with the challenging environment of the planned high luminosity upgrade of the Large Hadron Collider (HL-LHC), scheduled to start operation in 2029, CMS will replace its entire tracking system. The requirements for the tracker are largely determined by the long operation time of 10 years with an instantaneous peak luminosity of up to 7.5 x 1034 cm-2 s-1 in the ultimate performance scenario. Depending on the radial distance from the interaction point, the silicon sensors will receive a particle fluence corresponding to a non-ionising energy loss of up to ?eq = 3.5 x 1016 cm-2. This paper focuses on planar pixel sensor design and qualification up to a fluence of ?eq = 1.4 x 1016 cm-2. For the development of appropriate planar pixel sensors an R&D program was initiated, which includes n+-p sensors on 150 mm (6") wafers with an active thickness of 150 mu m with pixel sizes of 100 x 25 mu m2 and 50 x 50 mu m2 manufactured by Hamamatsu Photonics K.K. (HPK). Single chip modules with ROC4Sens and RD53A readout chips were made. Irradiation with protons and neutrons, as well was an extensive test beam campaign at DESY were carried out. This paper presents the investigation of various assemblies mainly with ROC4Sens readout chips. It demonstrates that multiple designs fulfil the requirements in terms of breakdown voltage, leakage current and efficiency. The single point resolution for 50 x 50 mu m2 pixels is measured as 4.0 mu m for non-irradiated samples, and 6.3 mu m after irradiation to ?eq = 7.2 x 1015 cm-2.
We propose a new fixed-target experiment for the study of electromagnetic and hard probes of the Quark-Gluon Plasma (QGP) in heavy-ion collisions at the CERN SPS. The experiment aims at performing measurements of the dimuon spectrum from threshold up to the charmonium region, and of hadronic decays of charm and strange hadrons. It is based on a muon spectrometer, which includes a toroidal magnet and six planes of tracking detectors, coupled to a vertex spectrometer, equipped with Si MAPS immersed in a dipole field. High luminosity is an essential requirement for the experiment, with the goal of taking data with 10$^6$ incident ions/s, at collision energies ranging from $\sqrt{s_{\rm NN}} = 6.3$ GeV ($E_{\rm lab}= 20$ A GeV) to top SPS energy ($\sqrt{s_{\rm NN}} = 17.3$ GeV, $E_{\rm lab}= 158$ A GeV). This document presents the physics motivation, the foreseen experimental set-up including integration and radioprotection studies, the current detector choices together with the status of the corresponding R&D, and the outcome of physics performance studies. A preliminary cost evaluation is also carried out.
The Limadou collaboration includes all Italian scientists working on the project CSES (China Seismo-Electromagnetic Satellite), a constellation of satellites equipped with the most advanced technologies for correlating ionosphere perturbations with the occurrence of seismic events [2]. For the launch of CSES-02, scheduled for mid-2022, the collaboration is realizing the high-energy particle detector [1], aimed at detecting electrons and protons trapped in Earth's magnetosphere, with energies 5 MeV-100 MeV and 30 MeV-300 MeV respectively. This payload consists of a particle tracker, a trigger system and a calorimeter, which work in time-coincidence to accurately identify particles and measure their energy and trajectory. The tracker is based on monolithic active pixel sensors ALPIDE [4], an innovative platform with superior performances in the field of pixel detectors, developed for the upgrade of the ALICE experiment [5] at the LHC, at CERN. The challenge in the construction of the tracker has been to adapt the ALPIDE technology to the space environment and to the specifications of the space register. Lightness and stiffness, essential features for structures in a tracker module, needed to balance with the need for withstanding structural and vibrational stress in the extended range of temperature occurring in the launch phase. Proper material choice with high thermal conductivity for the heat dissipation, innovative design of thermal paths and structural test results guided the project of mechanics. The modular particle tracker consists of 5 turrets, each one made of 3 stacked staves, with 150 pixel sensors in total. For readout and control purposes, ALPIDE sensors are wire-bonded to flexible printed circuits, which enhances the fragility of the system and makes handling critical. Sensor supports in carbon fiber reinforced plastic and an external aluminum frame preserve the mechanical integrity and provide the essential thermal bridges for heat dissipation. We provide results from the intense campaign of structural, thermal and vibrational qualification tests that have been performed in compliance with the procedures required by the space register. It regards structure, module and turret elements. The envisaged solution is a novelty in the field of space applications and paves the way for important developments for particle and astroparticle physics experiments.
The High-Energy Particle Detector (HEPD) module is designed to measure the pitch angle and energy of electrons and protons fluxes trapped in the Earth Magnetosphere with energies 3-100 MeV and 30-300 MeV respectively. Because of the launch of the CSES-02 satellite, an interesting option for improving the HEPD is to endow the tracking module with ALPIDE monolithic active pixel, specifically developed for the ITS upgrade of ALICE experiment at CERN. In this work we present the project of a modular and compact particle tracker made of 5 turrets, making use of 150-pixel sensors equipped with Hybrid Integrated Circuit (HIC) and supported by Carbon Fiber Reinforced Plastics (CFRPs) staves housed in an aluminum case. All envisaged solutions have been validated with an intense campaign of qualification tests, concerning vibrations and thermal stresses. The HEPD-02 tracker project foreruns the massive usage of CFRPs for space initiatives both of scientific and exploratory nature.
Abstract Transcatheter left atrial appendage occlusion (LAAO) has emerged as a reliable tool to prevent thromboembolic events, in particular ischemic stroke, in patients with atrial fibrillation (AF) in the absence of mitral stenosis/valve prosthesis and contraindication to oral anticoagulation (OAC). Antiplatelet therapy (APT) is required after device implantation to prevent device–related thrombus (DRT). Previous studies provided conflicting results on the optimal APT regimen after LAAO. Thus, herein we aimed at assessing the comparative effectiveness and safety of distinct APT regimens. We conducted a real–world single–center observational study including consecutive AF patients that underwent LAAO at the University Hospital of Parma between October 2010 and June 2021. Clinical follow–up included all successfully implanted patients. Primary endpoint was net efficacy outcome, a composite of any ischemic or hemorrhagic event. Secondary endpoints were ischemic (any of the following: ischemic stroke, transient ischemic attack [TIA], DRT, systemic embolism) and hemorrhagic (major [≥3] bleedings according to Bleeding Academic Research Consortium [BARC] classification) complications alone. We enrolled a total of 130 patients (median age 77.0 [72.7;81.0] years; 78 [60.0%] men). History of hemorrhagic stroke in OAC (74 [56.9%]) was the main indication for LAAO. Technical procedure success was achieved in 123 (94.6%) patients. According to multidisciplinary team evaluation, immediately after LAAO, 39 (31.7%) patients received short (≤ 1 month)–dual APT (DAPT) consisting of cardioaspirin and clopidogrel, 35 (28.5%) long (>1, ≤12 months)–DAPT and 49 (39.8%) single APT (SAPT). At a median follow–up of 32 months, the incidence of primary endpoint was significantly lower in short–DAPT group (3 [7.7%] vs. 7 [20.0%] in long–DAPT vs. 14 [28.6%] in SAPT, p = 0.049], mainly driven by a lower occurrence of bleeding endpoint (0 [0.0] vs. 4 [11.4%] in long–DAPT vs. 9 [18.4%] in SAPT, p = 0.020) without differences in the incidence of ischemic endpoint (p = 0.916). Finally, comparison of the Kaplan–Meier curves showed that short–DAPT group had a higher primary endpoint–free survival (p = 0.015) compared to the others. In summary, our study highlighted that short (≤ 1 month)–DAPT regimen after LAAO is associated with better outcomes, mainly driven by reduction of major bleedings. Strong evidences arising from randomized trials are warranted to support these findings.
The Short Strip ASIC (SSA) is one of the four front-end chips designed for the upgrade of the CMS Outer Tracker for the High Luminosity LHC. Together with the Macro-Pixel ASIC (MPA) it will instrument modules containing a strip and a macro-pixel sensor stacked on top of each other. The SSA provides both full readout of the strip hit information when triggered, and, together with the MPA, correlated clusters called stubs from the two sensors for use by the CMS Level-1 (L1) trigger system. Results from the first prototype module consisting of a sensor and two SSA chips are presented. The prototype module has been characterized at the Fermilab Test Beam Facility using a 120 GeV proton beam.
The CMS Inner Tracker, made of silicon pixel modules, will be entirely replaced prior to the start of the High Luminosity LHC period. One of the crucial components of the new Inner Tracker system is the readout chip, being developed by the RD53 Collaboration, and in particular its analogue front-end, which receives the signal from the sensor and digitizes it. Three different analogue front-ends (Synchronous, Linear, and Differential) were designed and implemented in the RD53A demonstrator chip. A dedicated evaluation program was carried out to select the most suitable design to build a radiation tolerant pixel detector able to sustain high particle rates with high efficiency and a small fraction of spurious pixel hits. The test results showed that all three analogue front-ends presented strong points, but also limitations. The Differential front-end demonstrated very low noise, but the threshold tuning became problematic after irradiation. Moreover, a saturation in the preamplifier feedback loop affected the return of the signal to baseline and thus increased the dead time. The Synchronous front-end showed very good timing performance, but also higher noise. For the Linear front-end all of the parameters were within specification, although this design had the largest time walk. This limitation was addressed and mitigated in an improved design. The analysis of the advantages and disadvantages of the three front-ends in the context of the CMS Inner Tracker operation requirements led to the selection of the improved design Linear front-end for integration in the final CMS readout chip.
Abstract During the operation of the CMS experiment at the High-Luminosity LHC the silicon sensors of the Phase-2 Outer Tracker will be exposed to radiation levels that could potentially deteriorate their performance. Previous studies had determined that planar float zone silicon with n-doped strips on a p-doped substrate was preferred over p-doped strips on an n-doped substrate. The last step in evaluating the optimal design for the mass production of about 200 m2 of silicon sensors was to compare sensors of baseline thickness (about 300 μm) to thinned sensors (about 240 μm), which promised several benefits at high radiation levels because of the higher electric fields at the same bias voltage. This study provides a direct comparison of these two thicknesses in terms of sensor characteristics as well as charge collection and hit efficiency for fluences up to 1.5 × 1015 neq/cm2. The measurement results demonstrate that sensors with about 300 μm thickness will ensure excellent tracking performance even at the highest considered fluence levels expected for the Phase-2 Outer Tracker.
Abstract A 37 years old woman was referred to our hospital due to the onset since the previous day of vertigo associated with nausea and headache. Her previous history revealed an hospitalization ten years before for Tako Tsubo Cardiomyopathy, during which the diagnosis of left temporo-jugular catecholamine secreting paraganglioma was made. Subsequently, there were several hospitalizations for multiple cardiac manifestations, such as acute coronary syndrome during hypertensive crisis, acute pulmonary oedema, one relapse for TakoTsubo syndrome and then an episode of torsade de pointes (TdP) during hypokalemia and elongated QT. The surgical removal of the mass was always rejected by the patient, and therefore, only radiotherapy was performed with significant reduction of the tumour dimensions. Moreover, alpha and beta adrenergic blockers were always administrated. At the admission, she complained neurological symptoms, in particular balance disorder and dysmetria. Brain Computed tomography (CT) was performed and it showed left posterior cerebellar infarction in late acute clinical phase, without haemorrhage. The patient underwent angiography that excluded cerebral artery dissection but showed acute occlusion of posterior internal cerebral artery. Echocardiogram showed moderate left ventricular hypertrophy with normal global and segmental kinetics, left atrial dilatation; besides, left ventricular apical thrombus was excluded. Holter ECG monitoring showed very frequent polymorphic ventricular and supraventricular extrasystolic beats. Urinary metanephrines were markedly increased. In particular urinary normetanephrine was up to 9 times the upper limit of normality (4874 ug/L, normal range 162-527 ug/24 h). Since the surgical intervention was always refused, this case is a rare documentation of the several different cardiovascular clinical manifestation due to catecholamine secretion in a single patient. Paraganglioma could be a catecholamine secreting tumour that arises from cromaffin tissue of the sympathetic nervous system. Clinical manifestations of paraganglioma are extremely variable leading to its designation as "great mimic". Adrenal tumours are associated with several cardiovascular diseases including LV hypertrophy, myocardial infarction, cardiac arrhythmias, heart failure and Tako Tsubo cardiomyopathy. Cerebral accident is a rare manifestation of adrenergic crisis with several possible aetiologies such as vasospasm or cardioembolic events. In our clinical case, considering the type and localization of the cerebral ischemic injury, the stroke is likely to have a cardioembolic etiology. Apical left ventricular trombus and PFO were excluded. Therefore, in view of left atrial enlargement and the frequent supraventricular ectopy, even in the absence of documented arrhythmia, an undiagnosed episode of catecholamines induced atrial fibrillation was suspected, with subsequent cardioembolic event. Abstract P257 Figure.
Abstract Patient Presentation A 54 years old woman with dyslipidemia was admitted to the hospital due to the onset of persistent fever. She had no significant comorbidities and she had a known mitral valve prolapse, which was in clinical and echocardiographic follow-up since more than 15 years before. Two months before the hospitalization she underwent dental hygiene procedure without taking any antibiotic before. The procedure included scaling and polishing of the teeth, and she referred just a mild bleeding. After few days she reported the onset of fever and therefore she started to take amoxicilline/clavulanic acid but without any significant improvement of symptoms. Initial work up At the blood chemistry she had a mild leucocytosis with neutrophilia and a rise in inflammatory indices. The Chest x-ray was normal. A systolic murmur was evident at the physical examination. Therefore, Transthoracic Echocardiogram was performed, followed by Transesophageal Echocardiogram (see Figure). At the Echo there was a significant endocarditic involvement of the mitral valve with multiple vegetations, two on the posterior leaflet (scallop P1 and P3) and one on the anterior one (scallop A3); moreover, there was a flail of the posterior leaflet (scallop P1) with subsequent moderate to severe eccentric valve regurgitation. Diagnosis and management Diagnosis of Endocarditis was made and, thus, antibiotic therapy was started with gentamicin and daptomycin, then switched to ampicillin and ceftriaxone after the isolation at the blood culture of Enterococcus Faecalis sensitive to them. Cerebral CT was performed with no evidence of embolization. Finally, owing to the significant endocarditis of the mitral valve with associate moderate to severe regurgitation, the patient underwent surgical intervention with mitral valve replacement with bioprosthesis. Follow-up The post-operative period was regular with no significant complications. She had no more fever and the antibiotics were stopped after six weeks. Conclusion We reported the case of a severe endocarditic involvement of the mitral valve in a patient with known valvular prolapse, who did not take any antibiotic before a minor dental procedure. 2015 ESC guidelines on Endocarditis recommend to not perform antibiotic prophylaxis in patient with no valvular prosthesis but with other form of valvular disease, including mitral valve prolapse (Class III, level of evidence C). Most of the time, patients with other form of valvular disease (e.g. mitral valve prolapse, bicuspid aortic valve, calcific aortic stenosis) do not experience endocarditis, neither after dental procedures. However, this case shows that sometimes it can happen due to the abnormal conformation of the native valve and, hence, it makes us wonder whether the antibiotic therapy should be indicated before dental procedures in those kind of patients. Abstract P1304 Figure.
This documents describes the technical design and the expected performance of the Barrel DIRC detector for the PANDA experiment. The Barrel DIRC will provide hadronic charged particle identification in the polar angle range of $22^\circ$ to $140^\circ$ for particle momenta between 0.5 GeV/c and 3.5 GeV/c. The design is based on the successful BaBar DIRC with several key improvements. The performance and system cost were optimized in detailed detector simulations and validated with full system prototypes using particle beams at GSI and CERN. The final design meets or exceeds the PID goal of clean $π/K$ separation with at least 3 standard deviations over the entire phase space of charged kaons in the Barrel DIRC.
The (P) over bar ANDA (anti-Proton ANnihiliation at DArmstadt) experiment will be one of the four flagship experiments at the new international accelerator complex FAIR (Facility for Antiproton and Ion Research) in Darmstadt, Germany. (P) over bar ANDA will address fundamental questions of hadron physics and quantum chromodynamics using high-intensity cooled antiproton beams with momenta between 1.5 and 15 GeV/c and a design luminosity of up to 2 x 10(32) cm(-2) S-1. Excellent particle identification (PID) is crucial to the success of the (P) over bar ANDA physics program. Hadronic PID in the barrel region of the target spectrometer will be performed by a fast and compact Cherenkov counter using the detection of internally reflected Cherenkov light (DIRC) technology. It is designed to cover the polar angle range from 22 degrees to 140 degrees and will provide at least 3 standard deviations (s.d.) pi/K separation up to 3.5 GeV/c, matching the expected upper limit of the final state kaon momentum distribution from simulation. This documents describes the technical design and the expected performance of the (P) over bar ANDA Barrel DIRC detector. The design is based on the successful BaBar DIRC with several key improvements. The performance and system cost were optimized in detailed detector simulations and validated with full system prototypes using particle beams at GSI and CERN. The final design meets or exceeds the PID goal of clean pi/K separation with at least 3 s.d. over the entire phase space of charged kaons in the Barrel DIRC.
An abstract is not available for this content so a preview has been provided. As you have access to this content, a full PDF is available via the ‘Save PDF’ action button.