Port Hinterland Modelling Based on Port Choice

This paper presents a new approach for hinterland modelling based on the results of port choice modelling. The paper follows the idea that the shippers’ port choice is a trade-off between various objective and subjective factors. The presented model tackles the problem by applying the AHP method in order to obtain ports’ preference rates based on subjective factors, and combine them with objective factors, which include port operation costs, sailing times, and land transport costs using MILP. The ports’ hinterlands are modelled by finding the optimal port of choice for different locations across Europe and merging the identical results. The model can be used in order to produce captive hinterland of ports and can also be exploited in order to analyse how changes in the traffic infrastructure influence the size of hinterlands

Studies of irradiated AMS H35 CMOS detectors for the ATLAS tracker upgrade

Silicon detectors based on the HV-CMOS technology are being investigated as possible candidate for the outer layers of the ATLAS pixel detector for the High Luminosity LHC. In this framework the H35Demo ASIC has been produced in the 350 nm AMS technology (H35). The H35Demo chip has a large area ($18.49 \times 24.40 \, \mathrm{mm^2}$) and includes four different pixel matrices and three test structures. In this paper the radiation hardness properties, in particular the evolution of the depletion region with fluence is studied using edge-TCT on test structures. Measurements on the test structures from chips with different substrate resistivity are shown for non irradiated and irradiated devices up to a cumulative fluence of $2 \cdot 10^{15} \, \mathrm{1\,MeV\, n_{eq} / cm^{2}}$

Performance of irradiated thin n-in-p planar pixel sensors for the ATLAS Inner Tracker upgrade

The ATLAS collaboration will replace its tracking detector with new all silicon pixel and strip systems. This will allow to cope with the higher radiation and occupancy levels expected after the 5-fold increase in the luminosity of the LHC accelerator complex (HL-LHC). In the new tracking detector (ITk) pixel modules with increased granularity will implement to maintain the occupancy with a higher track density. In addition, both sensors and read-out chips composing the hybrid modules will be produced employing more radiation hard technologies with respect to the present pixel detector. Due to their outstanding performance in terms of radiation hardness, thin n-in-p sensors are promising candidates to instrument a section of the new pixel system. Recently produced and developed sensors of new designs will be presented. To test the sensors before interconnection to chips, a punch-through biasing structure has been implemented. Its design has been optimized to decrease the possible tracking efficiency losses observed. After irradiation, they were caused by the punch-through biasing structure. A sensor compatible with the ATLAS FE-I4 chip with a pixel size of 50x250 $\mathrm{\mu}$m$^{2}$, subdivided into smaller pixel implants of 30x30 $\mathrm{\mu}$m$^{2}$ size was designed to investigate the performance of the 50x50 $\mathrm{\mu}$m$^{2}$ pixel cells foreseen for the HL-LHC. Results on sensor performance of 50x250 and 50x50 $\mathrm{\mu}$m$^{2}$ pixel cells in terms of efficiency, charge collection and electric field properties are obtained with beam tests and the Transient Current Technique

Neutron irradiation test of depleted CMOS pixel detector prototypes

Charge collection properties of depleted CMOS pixel detector prototypes produced on p-type substrate of 2 k$\Omega$cm initial resistivity (by LFoundry 150 nm process) were studied using Edge-TCT method before and after neutron irradiation. The test structures were produced for investigation of CMOS technology in tracking detectors for experiments at HL-LHC upgrade. Measurements were made with passive detector structures in which current pulses induced on charge collecting electrodes could be directly observed. Thickness of depleted layer was estimated and studied as function of neutron irradiation fluence. An increase of depletion thickness was observed after first two irradiation steps to 1$\cdot$10$^{13}$ n/cm$^{2}$ and 5$\cdot$10$^{13}$ n/cm$^{2}$ and attributed to initial acceptor removal. At higher fluences the depletion thickness at given voltage decreases with increasing fluence because of radiation induced defects contributing to the effective space charge concentration. The behaviour is consistent with that of high resistivity silicon used for standard particle detectors. The measured thickness of the depleted layer after irradiation with 1$\cdot$10$^{15}$ n/cm$^{2}$ is more than 50 $\mu$m at 100 V bias. This is sufficient to guarantee satisfactory signal/noise performance on outer layers of pixel trackers in HL-LHC experiments

R&D Paths of Pixel Detectors for Vertex Tracking and Radiation Imaging

This report reviews current trends in the R&D of semiconductor pixellated sensors for vertex tracking and radiation imaging. It identifies requirements of future HEP experiments at colliders, needed technological breakthroughs and highlights the relation to radiation detection and imaging applications in other fields of science.Comment: 17 pages, 2 figures, submitted to the European Strategy Preparatory Grou

Leakage current simulations of Low Gain Avalanche Diode with improved Radiation Damage Modeling

We report precise TCAD simulations of IHEP-IME-v1 Low Gain Avalanche Diode (LGAD) calibrated by secondary ion mass spectroscopy (SIMS). Our setup allows us to evaluate the leakage current, capacitance, and breakdown voltage of LGAD, which agree with measurements' results before irradiation. And we propose an improved LGAD Radiation Damage Model (LRDM) which combines local acceptor removal with global deep energy levels. The LRDM is applied to the IHEP-IME-v1 LGAD and able to predict the leakage current well at -30 $^{\circ}$C after an irradiation fluence of $\Phi_{eq}=2.5 \times 10^{15} ~n_{eq}/cm^{2}$. The charge collection efficiency (CCE) is under development

Search for the neutral Higgs bosons of the minimal supersymmetric standard model in pp collisions at root s=7 TeV with the ATLAS detector

A search for neutral Higgs bosons of the Minimal Supersymmetric Standard Model (MSSM) is reported. The analysis is based on a sample of proton-proton collisions at a centre-of-mass energy of 7TeV recorded with the ATLAS detector at the Large Hadron Collider. The data were recorded in 2011 and correspond to an integrated luminosity of 4.7 fb-1 to 4.8 fb-1. Higgs boson decays into oppositely-charged muon or τ lepton pairs are considered for final states requiring either the presence or absence of b-jets. No statistically significant excess over the expected background is observed and exclusion limits at the 95% confidence level are derived. The exclusion limits are for the production cross-section of a generic neutral Higgs boson, φ, as a function of the Higgs boson mass and for h/A/H production in the MSSM as a function of the parameters mA and tan β in the mhmax scenario for mA in the range of 90GeV to 500 GeV. Copyright CERN