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An X-ray BPM and accompanying electronics

Recent experiments at the Brazilian Synchrotron Ligth Source (LNLS) Ultra Violet and X-Ray beamlines are pushing on the Synchrotron Radiation (SR) beam position stability requirements. In the direction of having photon Beam Position Monitor integrated to the orbit closed loop control system, we developed a staggered blades XR BPM and a four-channel current measurement electronics. The BPM mechanic

Commissioning of the high intensity proton source developed at INFN-LNS for the European spallation source

At the Istituto Nazionale di Fisica Nucleare – Laboratori Nazionali del Sud (INFN-LNS) the commissioning of the high intensity Proton Source for the European Spallation Source (PS-ESS) started some weeks ago. Beam stability at high current intensity is one of the most important parameter for the first steps of the ongoing commissioning. Commissioning plan and preliminary characterization are also

Plasma surface treatments of poly(l-lactic acid) (PLLA) and poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV)

The surfaces of poly(l-lactic acid) (PLLA) and poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) were modified by oxygen and nitrogen plasma treatments. The physical and chemical surface characteristics were evaluated by contact angle tests, scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS). The plasma treatments caused an increase in both

Commissioning of the LNLS elliptically polarizing undulator

We present the results of the commissioning of the first Elliptically Polarizing Undulator (EPU) to be installed at the 1.37 GeV electron storage ring of the Brazilian Synchrotron Light Source (LNLS). The undulator is designed to provide UV and soft X-ray photons from 100 eV up to 1 keV with full polarization control. It uses the APPLE II design and allows for both parallel and anti-parallel longi

Commissioning of the LNLS 2 T Hybrid Wiggler

We present the results of the commissioning of a 28-pole 2 T Hybrid Wiggler at the electron storage ring of the Brazilian Synchrotron Light National Laboratory (LNLS). The wiggler will be used mainly for protein crystallography and was optimized for the production of 12 keV photons. We describe the effects of the insertion device on the storage ring lattice, such as the correction of the linear tu

Design of button beam position monitor for the Brazilian Synchrotron light source

We present the electrical and mechanical design of a button beam position monitor (BPM) recently developed and installed in the UVX electron storage ring at the Brazilian Synchrotron Light Laboratory (LNLS). The first characterization results will also be presented. This development started when we observed strong correlation between false stripline BPM readings and the external temperature of thi

Characterization and Evaluation of Ti-Zr-V Non-evaporable Getter Films Used in Vacuum Systems

Among several methods used to obtain ultra-high vacuum (UHV) for particles accelerators chambers, it stands out the internal coating with metallic films capable of absorbing gases, called NEG (non-evaporable getter). Usually these materials are constituted by elements of great chemical reactivity and solubility (such as Ti, Zr, and V), at room temperature for oxygen and other gases typically found

No title

The substrate preparation for CVD diamond growth is of basic importance due to several reasons. A new molybdenum substrate preparation method, the aluminum oxide abrasion jetting, is introduced and compared with the traditional ones. Raman Scattering Spectroscopy (RSS) and Scanning Electron Microscopy (SEM) characterize CVD diamond films. CVD diamond films of good quality and uniformity were obtai

Design, development, construction and installation of a ceramic chamber for a pulsed kicker at LNLS storage ring

Following the upgrade of the LNLS injector system with the addition of a 500 MeV booster synchrotron, the storage ring in vacuum ferrite injection kicker magnets started to show overheating due the interaction with high frequency electromagnetic fields induced by the electron beam in large currents. In this paper, we describe the design of a new ceramic chamber for the kickers, which minimize this

Design, construction and commissionig of a NEG coated wiggler vacuum chamber for the LNLS storage ring

We present the design of the vacuum chamber for the LNLS 2T Hybrid Wiggler. The chamber is a 3m long, 1.2mm thick 316L SS tube, which was mechanically pressed into an elliptical shape from an originally round tube. In order to provide the necessary mechanical tolerances, the rather flexible tube is welded to lateral supports that run the complete length of the chamber. Special care has been given

Nuclear level density and γ -ray strength function of Ni 67 and the impact on the i process

Proton-γ coincidences from (d,p) reactions between a Ni66 beam and a deuterated polyethylene target have been analyzed with the inverse-Oslo method to find the nuclear level density (NLD) and γ-ray strength function (γSF) of Ni67. The Ni66(n,γ) capture cross section has been calculated using the Hauser-Feshbach model in TALYS using the measured NLD and γSF as constraints. The results confirm that

Optical Diagnostics of a Gliding Arc Discharge at Atmospheric Pressure

A gliding arc discharge can be generated between two diverging electrodes and extended by a turbulent gas flow to form a plume of stable non-thermal plasmas sustained at atmospheric pressure. Gliding arc discharge is rather complicated since it involves plasma chemistry, flow dynamics and discharge-turbulence interaction. Optical techniques, especially laser-based methods, are able to perform in-s

Methodologies for velocimetry and flow visualization in supersonic flows enabled by CO2 seeding

A high spatiotemporal resolution technique for instantaneous flow field measurement has been developed, enabling one-dimensional velocimetry and flow field visualization within a converging–diverging nozzle. By employing femtosecond laser-induced long-lived, high-intensity plasma emission in a CO2/N2 gas flow, coupled with an ICCD camera, we achieved instantaneous one-dimensional velocity measurem

Light extinction and scattering to determine nanoparticle formation rates during droplet jetting in aluminum dust flames

The combustion of aluminum powder enables a CO2-free generation of heat and electricity. To understand the asymmetric combustion of burning aluminum particles, we imaged light extinction and scattering with high speed and magnification. In the flame, particles melt, ignite, and build up a spherical flame sheet of condensed-phase alumina around the droplet. Shortly thereafter, the asymmetric stage

Barbara Czarniawska (1948–2024) : reflections in memory of her work and life

Purpose: This paper presents a reflection in memory and tribute to the work and life of Professor Barbara Czarniawska (1948–2024). Design/methodology/approach: We invited those colleagues whom we knew to be close to Barbara to submit reflections about her contributions to academia alongside their memories of her as a person. We present these reflections in the order we received them, and they have

Early-Life Diet Diversity and the Subsequent Risk of Inflammatory Bowel Disease: Findings From Two Scandinavian Birth Cohorts

BackgroundDiet diversity in early childhood promotes microbial diversity, influences the developing immune system, and has been linked to a reduced risk of immune-mediated diseases. This study aimed to determine the association between childhood diet diversity and later inflammatory bowel disease (IBD), for which data are limited.MethodsQuestionnaire data from the population-based birth cohorts Al

Facile In Situ Formation of Potassium Sodium Niobate (KNN) Using The Hexaniobate Polyoxometalate

Lead-based piezoceramics are the dominant materials used in electronic devices, despite the known toxicity of lead. Developing safer piezoelectric materials has inspired the pursuit of lead-free piezoceramics, however some challenges remain in accessing these materials reproducibly. Here we demonstrate a simple and robust method for synthesis of the lead-free piezoceramic material, potassium sodiu