Now showing items 21-40 of 543

• #### How the IMF By induces a By component in the closed magnetosphere and how it leads to asymmetric currents and convection patterns in the two hemispheres ﻿

(Wiley, 2015-11-12)
We used the Lyon-Fedder-Mobarry global magnetohydrodynamics model to study the effects of the interplanetary magnetic field (IMF) By component on the coupling between the solar wind and magnetosphere-ionosphere system. ...
Journal article
• #### Enhanced detection of terrestrial gamma-ray flashes by AGILE ﻿

(AGU Publications, 2015-11-06)
At the end of March 2015 the onboard software configuration of the Astrorivelatore Gamma a Immagini Leggero (AGILE) satellite was modified in order to disable the veto signal of the anticoincidence shield for the minicalorimeter ...
Journal article
• #### Positron bunching and electrostatic transport system for the production and emission of dense positronium clouds into vacuum ﻿

(Elsevier, 2015-11)
We describe a system designed to re-bunch positron pulses delivered by an accumulator supplied by a positron source and a Surko-trap. Positron pulses from the accumulator are magnetically guided in a 0.085 T field and are ...
Journal article
• #### Scintillation and loss of signal lock from poleward moving auroral forms in the cusp ionosphere ﻿

(Wiley, 2015-10-27)
We present two examples from the cusp ionosphere over Svalbard, where poleward moving auroral forms (PMAFs) are causing significant phase scintillation in signals from navigation satellites. The data were obtained using a ...
Journal article
• #### A giant reconstruction of α-quartz (0001) interpreted as three domains of nano dauphine twins ﻿

(Europe PMC, 2015-10-08)
Silica (SiO2) is one of the most common materials on Earth. The crystalline form α-quartz is the stable silica polymorph at ambient conditions although metastable forms exist. α-quartz is a piezoelectric material, it can ...
Journal article
• #### Measurement of charged jet production cross sections and nuclear modification in p-Pb collisions at $\sqrt{s_\rm{NN}} = 5.02$ TeV ﻿

(Elsevier, 2015-10)
Charged jet production cross sections in p-Pb collisions at $\sqrt{s_{\rm NN}} = 5.02$ TeV measured with the ALICE detector at the LHC are presented. Using the anti-$k_{\rm T}$ algorithm, jets have been reconstructed in ...
Journal article
• #### Network analysis of geomagnetic substorms using the SuperMAG database of ground-based magnetometer stations ﻿

(Wiley, 2015-09-26)
The overall morphology and dynamics of magnetospheric substorms is well established in terms of the observed qualitative auroral features seen in ground-based magnetometers. This paper focuses on the quantitative ...
Journal article
• #### Combined positron emission tomography and computed tomography to visualize and quantify fluid flow in sedimentary rocks ﻿

(AGU (American Geophysical Union) Publications, 2015-09-22)
Here we show for the first time the combined positron emission tomography (PET) and computed tomography (CT) imaging of flow processes within porous rocks to quantify the development in local fluid saturations. The coupling ...
Journal article
• #### Nonlinear echoes from encapsulated antibubbles ﻿

(Elsevier B.V., 2015-09-19)
An antibubble consists of a liquid droplet, surrounded by a gas, often with an encapsulating shell. Antibubbles of microscopic sizes suspended in fluids are acoustically active in the ultrasonic range. Antibubbles have ...
Journal article
• #### Birkeland current effects on high-latitude ground magnetic field perturbations ﻿

(Wiley, 2015-09-18)
Magnetic perturbations on ground at high latitudes are directly associated only with the divergence-free component of the height-integrated horizontal ionospheric current, J⊥,df. Here we show how J⊥,df can be expressed as ...
Journal article
• #### Flow visualization of CO2 in tight shale formations at reservoir conditions ﻿

(Agu publications, 2015-09-18)
The flow of CO2 in porous media is fundamental to many engineering applications and geophysical processes. Yet detailed CO2 flow visualization remains challenging. We address this problem via positron emission tomography ...
Journal article
• #### ALICE TPC Upgrade Activities for LHC Run 3 and Beyond: "SAMPA ASIC Tests with GEM Detector Prototype" ﻿

(The University of Bergen, 2015-09-11)
The Time Projection Chamber (TPC) signal readout of the ALICE detector is being upgraded to accommodate the higher collision rates and -energies during LHC Run 3 in 2018. Due to the increased collision rates, the TPC drift ...
Master thesis
• #### Near-surface petrochemical sensing using coplanar waveguides ﻿

(The University of Bergen, 2015-09-11)
The project studies the ability of coplanar waveguide sensor in sensing thin layers of petrochemical liquid. A coplanar waveguide is built on flexible printable circuit board partially based on an existing design. Two ...
Master thesis
• #### A study of the Coriolis flowmeter as a reference instrument in multiphase flow ﻿

(The University of Bergen, 2015-09-11)
The objective of this thesis was to investigate how a two-liquid mixture, and injected gas, affects the measurements of a Coriolis flowmeter. Furthermore it was of interest to investigate whether entrained gas could be ...
Master thesis
• #### Measurement of charged-particle spectra in Pb+Pb collisions at (Formula presented.) = 2.76 TeV with the ATLAS detector at the LHC ﻿

(Springer, 2015-09-09)
Charged-particle spectra obtained in Pb+Pb interactions at sNN−−−√=2.76 TeV and pp interactions at sNN−−−√=2.76 TeV with the ATLAS detector at the LHC are presented, using data with integrated luminosities of 0.15 nb−1 and ...
Journal article
• #### Measurement of the forward-backward asymmetry of electron and muon pair-production in pp collisions at (Formula Presented.) = 7 TeV with the ATLAS detector ﻿

(Springer, 2015-09-09)
This paper presents measurements from the ATLAS experiment of the forward-backward asymmetry in the reaction pp → Z/γ * → l + l −, with l being electrons or muons, and the extraction of the effective weak mixing angle. The ...
Journal article
• #### Medical physics aspects of the synchrotron radiation therapies: Microbeam radiation therapy (MRT) and synchrotron stereotactic radiotherapy (SSRT) ﻿

(Elsevier, 2015-09)
Stereotactic Synchrotron Radiotherapy (SSRT) and Microbeam Radiation Therapy (MRT) are both novel approaches to treat brain tumor and potentially other tumors using synchrotron radiation. Although the techniques differ by ...
Journal article
• #### Testing hadronic interaction models using a highly granular silicon-tungsten calorimeter ﻿

(Elsevier, 2015-09)
Journal article
• #### Search for heavy lepton resonances decaying to a $Z$ boson and a lepton in $pp$ collisions at $\sqrt{s}=8$ TeV with the ATLAS detector ﻿

(Springer, 2015-09)
A search for heavy leptons decaying to a $Z$ boson and an electron or a muon is presented. The search is based on $pp$ collision data taken at $\sqrt{s}=8$ TeV by the ATLAS experiment at the CERN Large Hadron Collider, ...
Journal article
• #### Neutral Pion Production in p-Pb Collisions at √s^NN = 5.02 TeV with ALICE PHOS at the LHC ﻿

(The University of Bergen, 2015-08-24)
In this thesis, the neutral mesons measurement with ALICE PHOS at the LHC is presented. Depending on the technical design of PHOS and its momentum reach, the strategies of the neutral mesons extraction by invariant mass ...
Master thesis