Performance of novel silicon n-in-p planar Pixel Sensors

The performance of novel n-in-p planar pixel detectors, designed for future upgrades of the ATLAS Pixel system is presented. The n-in-p silicon sensors technology is a promising candidate for the pixel upgrade thanks to its radiation hardness and cost effectiveness, that allow for enlarging the area instrumented with pixel detectors. The n-in-p modules presented here are composed of pixel sensors produced by CiS connected by bump-bonding to the ATLAS readout chip FE-I3. The characterization of these devices has been performed before and after irradiation up to a fluence of 5 x 10**15 1 MeV neq cm-2 . Charge collection measurements carried out with radioactive sources have proven the functioning of this technology up to these particle fluences. First results from beam test data with a 120 GeV/c pion beam at the CERN-SPS are also discussed, demonstrating a high tracking efficiency of (98.6 \pm 0.3)% and a high collected charge of about 10 ke for a device irradiated at the maximum fluence and biased at 1 kV.Comment: Preprint submitted to Nuclear Instruments and Methods A. 7 pages, 13 figure

Novel Silicon n-in-p Pixel Sensors for the future ATLAS Upgrades

In view of the LHC upgrade phases towards HL-LHC the ATLAS experiment plans to upgrade the Inner Detector with an all silicon system. The n-in-p silicon technology is a promising candidate for the pixel upgrade thanks to its radiation hardness and cost effectiveness, that allow for enlarging the area instrumented with pixel detectors. We present the characterization and performance of novel n-in-p planar pixel sensors produced by CiS (Germany) connected by bump bonding to the ATLAS readout chip FE-I3. These results are obtained before and after irradiation up to a fluence of 10^16 1-MeV n_eq/cm^2, and prove the operability of this kind of sensors in the harsh radiation environment foreseen for the pixel system at HL-LHC. We also present an overview of the new pixel production, which is on-going at CiS for sensors compatible with the new ATLAS readout chip FE-I4.Comment: Preprint submitted to NIM-A Proceedings (Elba 2012

Performance of n-in-p pixel detectors irradiated at fluences up to 5x10**15 neq/cm**2 for the future ATLAS upgrades

We present the results of the characterization of novel n-in-p planar pixel detectors, designed for the future upgrades of the ATLAS pixel system. N-in-p silicon devices are a promising candidate to replace the n-in-n sensors thanks to their radiation hardness and cost effectiveness, that allow for enlarging the area instrumented with pixel detectors. The n-in-p modules presented here are composed of pixel sensors produced by CiS connected by bump-bonding to the ATLAS readout chip FE-I3. The characterization of these devices has been performed with the ATLAS pixel read-out systems, TurboDAQ and USBPIX, before and after irradiation with 25 MeV protons and neutrons up to a fluence of 5x10**15 neq /cm2. The charge collection measurements carried out with radioactive sources have proven the feasibility of employing this kind of detectors up to these particle fluences. The collected charge has been measured to be for any fluence in excess of twice the value of the FE-I3 threshold, tuned to 3200 e. The first results from beam test data with 120 GeV pions at the CERN-SPS are also presented, demonstrating a high tracking efficiency before irradiation and a high collected charge for a device irradiated at 10**15 neq /cm2. This work has been performed within the framework of the RD50 Collaboration.Comment: Proceedings of the Conference "Technology and Instrumentation in Particle Physics 2011

Plate-Boundary Kinematics of the Afrera Linkage Zone (Afar) From InSAR and Seismicity

International audienceStudying the mechanisms of interaction between rift segments is key to understanding the kinematics of plate boundaries in continental rifts. However, the spatial and temporal evolution of deformation at rift linkage zones is rarely observed directly. Here, we combine InSAR data spanning 2005–2010 and 2014–2019 from ENVISAT and Sentinel-1 satellites, respectively, with local seismicity from the Afar rift to investigate the plate-boundary kinematics of the Afrera linkage zone, the junction between the Erta Ale and Tat Ali magmatic segments in Northern Afar (Ethiopia). We obtain time-series of cumulative InSAR Line-Of-Sight (LOS) displacements that show deformation is accommodated by a series of active en-echelon faults striking ∼NS and characterized by normal slip associated with a left-lateral strike-slip component. Additionally, we observe spatial variation in fault behavior with stick-slip and creep. The faults in the center of the linkage zone behave primarily in a stick-slip mode (with abrupt fault displacements up to ∼40 mm) and fault motions are associated with earthquakes of ML > 5. Conversely, faults at the edge of the linkage zone, near the magmatic segments, show creep and some stick-slip behavior (with cumulative LOS displacement up to ∼30–40 mm over a ∼5-year period) accompanied by low-level seismicity. Some of the creeping faults are also spatially associated with hydrothermal springs. We interpret that the temporal behavior of the faults in the linkage zone is controlled by the interplay between tectonic extension, high heat flows, and fluid circulation near the magmatic segments where creeping of some faults is favored

Enhanced Joule Heating in Umbral Dots

We present a study of magnetic profiles of umbral dots (UDs) and its consequences on the Joule heating mechanisms. Hamedivafa (2003) studied Joule heating using vertical component of magnetic field. In this paper UDs magnetic profile has been investigated including the new azimuthal component of magnetic field which might explain the relatively larger enhancement of Joule heating causing more brightness near circumference of UD.Comment: 8 pages, 1 figure, accepted in Solar Physic

Current clinical practice in disabling and chronic migraine in the primary care setting: results from the European My-LIFE anamnesis survey.

Migraine is a prevalent and disabling headache disorder that affects more than 1.04 billion individuals world-wide. It can result in reduction in quality of life, increased disability, and high socio-economic burden. Nevertheless, and despite the availability of evidence-based national and international guidelines, the management of migraine patients often remains suboptimal, especially for chronic migraine (CM) patients. My-LIFE anamnesis project surveyed 201 General practitioners (GPs) from 5 European countries (France, Germany, Italy, Spain, and the UK) with the aim of understanding chronic migraine (CM) patients' management in the primary care setting. In our survey, GPs diagnosed episodic migraine (EM) more often than CM (87% vs 61%, p < 0.001). We found that many CM patients were not properly managed or referred to specialists, in contrast to guidelines recommendations. The main tools used by primary-care physicians included clinical interview, anamnesis guide, and patient diary. Tools used at the first visit differed from those used at follow-up visits. Up to 82% of GPs reported being responsible for management of patients diagnosed with disabling or CM and did not refer them to a specialist. Even when the GP had reported referring CM patients to a specialist, 97% of them were responsible for their follow-up. Moreover, the treatment prescribed, both acute and preventive, was not in accordance with local and international recommendations. GPs reported that they evaluated the efficacy of the treatment prescribed mainly through patient perception, and the frequency of follow-up visits was not clearly established in the primary care setting. These results suggest that CM is underdiagnosed and undertreated; thereby its management is suboptimal in the primary care. There is a need of guidance in the primary care setting to both leverage the management of CM patients and earlier referral to specialists, when appropriate

Third-order nonlinear optical response and photoluminescence characterization of tellurite glasses with different alkali metal oxides as network modifiers

Studies of the third-order nonlinear optical properties in TeO(2)-MO-R(2)O glasses with three different alkali metal oxides R(2)O (R - Li, Na, K) as network modifiers and two network intermediates MO (M - Zn, Mg) are reported. The influence of such modifiers and intermediates on the nonlinear optical properties of these glasses was investigated using the standard Z-scan and the thermally managed Z-scan techniques under femtosecond pulse excitation at 800 nm. For different modifiers and intermediates, the nonlinear refraction indices n(2) of these glasses varied in the range 1.31-2.81 (x10(-15) cm(2)/W). It was found that n(2) increases as the ionic radius of both network modifiers and intermediates decreases. Furthermore, the measurements show that the contribution from thermo-optical effects to the nonlinear refraction index is negligible for all of the studied glass compositions. In addition, the effect of modifiers and intermediates in the formation of localized states in the vicinity of the optical bandgap was also studied through photoluminescence experiments. These experiments revealed the presence of two emission bands (red and blue) originating from these localized states that can be populated after optical excitation and subsequent relaxation

Merging of Low-Mass Systems and the Origin of the Fundamental Plane

We present a new set of dissipationless N-body simulations to examine the feasibility of creating bright ellipticals (following the Kormendy relation) by hierarchically merging present-day early-type dwarf galaxies, and to study how the encounter parameters affect the location of the end-product in the $- R_{e}$ plane. We investigate the merging of one-component galaxies of both equal and different masses, the merging of two-component galaxy models to explore the effect of dark halos on the final galaxy characteristics, and the merging of ultracompact dwarf galaxies. We find that the increase of $$ with $R_e$ is attributable to an increase in the initial orbital energy. The merger remnants shift down in the $- R_{e}$ plane and fail to reach the KR. Thus, the KR is not reproducable by mergers of dwarf early-type systems, rendering untenable the theory that present-day dwarfs are responsible for even a small fraction of the present-day ellipticals, unless a considerable amount of dissipation is invoked. However, we do find that present-day dwarfs can be formed by the merger of ultra-compact dwarfs.Comment: 10 pages, 8 figures. Accepted for publication in MNRA