47 research outputs found
Proton dripline studies at ISOLDE: Ar and C
In this contribution examples of the application of new technologies to disentangle the mechanism of -delayed multiparticle emission are given. In particular the mechanism of 2p-emission from Ar has been resolved and proved to be sequential, a preview of C-decay data is discussed
Silver nanowires as transparent conductive films in the near-infrared spectral range
Transparent conductive films (TCFs) comprise a crucial component of optoelectronic devices, such as displays, light-emitting diodes, solar cells and touch screens. Indium tin oxide (ITO) currently dominates among TCFs in the visible spectral range due to the high transmittance at low resistivity. However, the remarkable decrease of the transmittance in the near-infrared range (NIR) restricts from using ITO as highly efficient NIR TCF. Here we show that silver nanowires (AgNWs) possesses up to 95% transmittance for whole 0.75-2.5|jm near-infrared spectral range
ПАССИВНО-МАТРИЧНЫЕ МИКРОДИСПЛЕИ СВЕТОИЗЛУЧАЮЩЕГО ТИПА
The construction, technology and main features of passive matrix light emitting microdisplays based on reverse biesed Schottki diodes with the structure of nanoporous Silicon-Aluminium are described.Описаны конструкция, технология и основные параметры пассивно-матричного микродисплея светоизлучающего типа на основе Шоттки-структуры нанопористый кремний/алюминий для персональных видеопроекционных систем с улучшенными потребительскими свойствами. Контроль их функционирования осуществлялся визуально с помощью специально разработанных методики и программно-аппаратного комплекса, включающего генератор испытательных сигналов в виде набора тестовых полей и программного обеспечения, установленного на персональном компьютере с операционной системой Windows XP
ТОНКОПЛЕНОЧНЫЕ ТРАНЗИСТОРЫ С InGaZnO-ПОЛУПРОВОДНИКОВЫМ СЛОЕМ ДЛЯ АКТИВНО-МАТРИЧНОЙ АДРЕСАЦИИ
The paper presents the results of a study of thin-film transistors based on the InGaZnO semiconductor compound (IGZO) for active-matrix displays addressing formed by magnetron plasma-chemical deposition. Their structural-morphological and electrophysical properties are investigated. Carrier mobility is analyzed using the Hall method. The effect of annealing in vacuum, an oxygen atmosphere, and a nitrogen atmosphere on the grain size of an IGZO film was investigated. The resulting layers are characterized by high mobility of charge carriers, which allows their use in the manufacture of new-generation LCD and OLED displays.В работе представлены результаты исследования тонкопленочных транзисторов на основе полупроводникового соединения InGaZnO (IGZO) для активно-матричной адресации дисплеев, формируемого методом магнетронного плазмохимического осаждения. Исследованы их структурно- морфологические и электрофизические свойства. Проведен анализ подвижности носителей заряда методом Холла. Изучено влияние отжига в вакууме, атмосфере кислорода и атмосфере азота на размер зерен пленки IGZO. Полученные слои характеризуются высокой подвижностью носителей заряда, что позволяет их использовать при изготовлении ЖК- и OLED-дисплеев нового поколения
Тонкопленочные транзисторы с InGaZnO-полупроводниковым слоем для активно-матричной адресации
В работе представлены результаты исследования тонкопленочных транзисторов на основе
полупроводникового соединения InGaZnO (IGZO) для активно-матричной адресации дисплеев,
формируемого методом магнетронного плазмохимического осаждения. Исследованы их структурно-
морфологические и электрофизические свойства. Проведен анализ подвижности носителей заряда
методом Холла. Изучено влияние отжига в вакууме, атмосфере кислорода и атмосфере азота на размер
зерен пленки IGZO. Полученные слои характеризуются высокой подвижностью носителей заряда,
что позволяет их использовать при изготовлении ЖК- и OLED-дисплеев нового поколения
Precision of the PET activity range during irradiation with <sup>10</sup>C, <sup>11</sup>C, and <sup>12</sup>C beams
Objective. Beams of stable ions have been a well-established tool for radiotherapy for many decades. In the case of ion beam therapy with stable 12C ions, the positron emitters 10,11C are produced via projectile and target fragmentation, and their decays enable visualization of the beam via positron emission tomography (PET). However, the PET activity peak matches the Bragg peak only roughly and PET counting statistics is low. These issues can be mitigated by using a short-lived positron emitter as a therapeutic beam. Approach. An experiment studying the precision of the measurement of ranges of positron-emitting carbon isotopes by means of PET has been performed at the FRS fragment-separator facility of GSI Helmholtzzentrum für Schwerionenforschung GmbH, Germany. The PET scanner used in the experiment is a dual-panel version of a Siemens Biograph mCT PET scanner. Main results. High-quality in-beam PET images and activity distributions have been measured from the in-flight produced positron emitting isotopes 11C and 10C implanted into homogeneous PMMA phantoms. Taking advantage of the high statistics obtained in this experiment, we investigated the time evolution of the uncertainty of the range determined by means of PET during the course of irradiation, and show that the uncertainty improves with the inverse square root of the number of PET counts. The uncertainty is thus fully determined by the PET counting statistics. During the delivery of 1.6 × 107 ions in 4 spills for a total duration of 19.2 s, the PET activity range uncertainty for 10C, 11C and 12C is 0.04 mm, 0.7 mm and 1.3 mm, respectively. The gain in precision related to the PET counting statistics is thus much larger when going from 11C to 10C than when going from 12C to 11C. The much better precision for 10C is due to its much shorter half-life, which, contrary to the case of 11C, also enables to include the in-spill data in the image formation. Significance. Our results can be used to estimate the contribution from PET counting statistics to the precision of range determination in a particular carbon therapy situation, taking into account the irradiation scenario, the required dose and the PET scanner characteristics.</p
High-resolution measurement of the time-modulated orbital electron-capture and of the decay of hydrogen-like ions
Storage, Accumulation and Deceleration of Secondary Beams for Nuclear Astrophysics
Low-energy investigations on rare ion beams are often limited by the
available intensity and purity of the ion species in focus. Here, we present
the first application of a technique that combines in-flight production at
relativistic energies with subsequent secondary beam storage, accumulation and
finally deceleration to the energy of interest. Using the FRS and ESR
facilities at GSI, this scheme was pioneered to provide a secondary beam of
Te for the measurement of nuclear proton-capture at energies of
6 and 7 MeV/u. The technique provided stored beam intensities of about
ions at high purity and brilliance, representing a major step towards
low-energy nuclear physics studies using rare ion beams
Precision of the PET activity range during irradiation with ¹⁰C, ¹¹C, and ¹²C beams
Objective. Beams of stable ions have been a well-established tool for radiotherapy for many decades. In the case of ion beam therapy with stable ¹²C ions, the positron emitters ¹⁰,¹¹C are produced via projectile and target fragmentation, and their decays enable visualization of the beam via positron emission tomography (PET). However, the PET activity peak matches the Bragg peak only roughly and PET counting statistics is low. These issues can be mitigated by using a short-lived positron emitter as a therapeutic beam. Approach. An experiment studying the precision of the measurement of ranges of positron-emitting carbon isotopes by means of PET has been performed at the FRS fragment-separator facility of GSI Helmholtzzentrum für Schwerionenforschung GmbH, Germany. The PET scanner used in the experiment is a dual-panel version of a Siemens Biograph mCT PET scanner. Main results. High-quality in-beam PET images and activity distributions have been measured from the in-flight produced positron emitting isotopes ¹¹C and ¹⁰C implanted into homogeneous PMMA phantoms. Taking advantage of the high statistics obtained in this experiment, we investigated the time evolution of the uncertainty of the range determined by means of PET during the course of irradiation, and show that the uncertainty improves with the inverse square root of the number of PET counts. The uncertainty is thus fully determined by the PET counting statistics. During the delivery of 1.6 × 10⁷ ions in 4 spills for a total duration of 19.2 s, the PET activity range uncertainty for ¹⁰C, ¹¹C and ¹²C is 0.04 mm, 0.7 mm and 1.3 mm, respectively. The gain in precision related to the PET counting statistics is thus much larger when going from ¹¹C to ¹⁰C than when going from ¹²C to ¹¹C. The much better precision for ¹⁰C is due to its much shorter half-life, which, contrary to the case of ¹¹C, also enables to include the in-spill data in the image formation. Significance. Our results can be used to estimate the contribution from PET counting statistics to the precision of range determination in a particular carbon therapy situation, taking into account the irradiation scenario, the required dose and the PET scanner characteristics
Fast-timing measurements in <sup>96</sup>Pd:improved accuracy for the lifetime of the 4<sup>+</sup><sub>1</sub> state
Direct lifetime measurements via γ–γ coincidences using the FATIMA fast-timing LaBr3(Ce) array were performed for the excited states below previously reported isomers. In the N = 50 semi-magic 96Pd nucleus, lifetimes below the I π = 8+ seniority isomer were addressed as a benchmark for further analysis. The results for the I π = 2+ and 4 + states confirm the published values. Increased accuracy for the lifetime value was achieved for the 4 + state.peerReviewe