Nuclear data measurements at the upgraded neutron time-of-flight facility n-TOF at CERN

Applications of nuclear data like neutron-induced reaction cross sections are related to research fields as stellar nucleosynthesis, the study of nuclear level densities and strength functions, and also play a key role in the safety and criticality assessment of existing and future nuclear reactors, in areas concerning radiation dosimetry, medical applications, transmutation of nuclear waste, accelerator-driven systems and fuel cycle investigations. The evaluations in nuclear data libraries are based both on experimental data and theoretical models. CERN’s neutron time-of-flight facility n_TOF has produced a considerable amount of experimental data since it has become fully operational with the start of its scientific measurement programme in 2002. While for a long period a single measurement station (EAR1) located at 185 m from the neutron production target was available, the construction of a second beam line at 20 m (EAR2) in 2014 has substantially increased the measurement capabilities of the facility. An outline of the experimental nuclear data activities at CERN’s neutron time-of-flight facility n_TOF will be presented.Postprint (published version

Elämyksiä ja kohtaamisia Hopeatien palvelutalon aistihuoneessa

Opinnäytetyön tavoitteena oli selvittää ikäihmisten kokemuksia aistihuoneen käytöstä ja kartoittaa, miten he voivat hyötyä aistihuoneesta. Apuvälineyritys Haltija Groupin SHX-aistihuoneen elementit siirrettiin Helsingin kaupungin Hopeatien palvelutaloon testikäyttöön kolmeksi kuukaudeksi. Opinnäytetyö pohjautuu Gary Kielhofnerin inhimillisen toiminnan malliin “Model of Human Occupation (MOHO)” ja sen keskeiset käsitteet ohjasivat tutkimusaineiston tiedon keruuta sekä sen analysointia. Opinnäytetyön muu teoreettinen perusta muodostui ikääntymisen tarkastelusta toimintakyvyn ja aistien näkökulmasta sekä multisensorisen toiminnan perusteista. Opinnäytetyö perustui laadullisen tutkimuksen periaatteisiin ja siinä oli kaksi työelämäkumppania: Helsingin kaupungin Hopeatien palvelutalo ja Haltija Group. Tutkimusmenetelmiksi valittiin aistihuoneen käyttäjille suunnattu kyselylomake sekä hoitohenkilökunnalle suunnattu ryhmämuotoinen teemahaastattelu. Kirjallinen raporttiosuus sisältää teoreettisen perustan, opinnäytetyön toteutuksen kuvauksen, aineiston analyysin, johtopäätökset ja pohdinnan. Tässä opinnäytetyössä asiakaslähtöisyys ja aistihuoneen esteettömyys nousivat seikoiksi, jotka vaikuttivat myönteisesti ikääntyneen osallistumiseen aistihuoneessa. Asiakkaan elämänhistorian ja mielenkiinnon kohteiden tunteminen sekä yksilöllisen tahdon ja suorituskyvyn huomioiminen koettiin tärkeiksi. Onnistuneeseen käyntiin aistihuoneessa vaikuttivat orientaatio ja henkilökunnan taito käyttää aistihuoneen tekniikkaa. Asiakkaiden kokemukset aistihuoneesta olivat pääosin miellyttäviä, jopa rentouttavia. Tämän opinnäytetyön tulokset ovat yhtenäisessä linjassa verrattuna aiempiin tutkimuksiin aistihuoneista ja niiden vaikutuksista. Opinnäytetyön perusteella aistihuoneen käyttö ikääntyneiden arjessa voi tarjota positiivisia vaikutuksia ikääntyneen psyykkiseen ja sosiaaliseen toimintakykyyn. Huolellinen suunnittelu, esteettömyys ja vahva asiakastuntemus mahdollistavat asiakkaan osallistumisen terapeuttiseen toimintaan aistihuoneessa. Aistihuoneen vaikuttavuudesta pitkällä aikavälillä tarvitaan lisää tutkimustietoa, jota voisi hyödyntää myös suunniteltaessa tulevaisuuden palveluja ikääntyneille.The object of the Bachelor’s thesis was to provide the elderly in the Hopeatie service house in Helsinki with the SHX multisensory elements for trial use. The purpose of this study was to find out experiences of elderly people in the multisensory room and analyze how they can benefit from the multisensory activities in their rehabilitation. The theory is based on Gary Kielhofner’s Model of Human Occupation (MOHO) and its essential concepts that steer the data gathering and analysis. The fundamental aspects of multisensory activities and ageing accompanied by changes in performance and impaired senses are also observed. This thesis is a qualitive study executed in collaboration with two working life partners: the city of Helsinki and Haltija Group, which is a Finnish company for assistive devices, welfare technology and rehabilitation. The thematic group interview of six employees of the service house and a client questionnaire were chosen as research methods. This thesis consists of theory, description of the implementation, data analysis, results of the study, and conclusions and discussion. The results show that the client-centered approach and the accessibility to the multisensory room had an influence on participation of the elderly in the multisensory room. Successful visits of the multisensory room were enabled by employees’ skills to prepare the client for the visit and their skills to master the technology of the room. The experiences of the elderly in the multisensory room were mainly pleasant, some even relaxing. The results of this study are consistent with previous research on the effects of a multisensory room. This study proves that the use of the multisensory room in the elderly people’s daily lives may have a positive effect on their mental and social performance. Thorough planning of therapy intervention, easy access to the multisensory room and strong client knowledge enable committed client participation. More research is needed for long-term effects of multisensory room in order to benefit from the results for planning services for the elderly in the future

First Measurement of 72Ge(n,γ) at n_TOF

9th European Summer School on Experimental Nuclear AstrophysicsThe slow neutron capture process (s-process) is responsible for producing about half of the elemental abundances heavier than iron in the universo

Recent results in nuclear astrophysics at the n_TOF facility at CERN

The neutron time of flight (n_TOF) facility at CERN is a spallation source characterized by a white neutron spectrum. The innovative features of the facility, in the two experimental areas, (20 m and 185 m), allow for an accurate determination of the neutron cross section for radioactive samples or for isotopes with small neutron capture cross section, of interest for Nuclear Astrophysics. The recent results obtained at n_TOF facility are presented

Operational Experience with a LHC Collimator Prototype in the CERN SPS

A full-scale prototype of the Large Hadron Collider (LHC) collimator was installed in 2004 in the CERN Super Proton Synchrotron (SPS) and has been extensively used for beam tests, for control tests and also LHC simulation benchmarking during four years of operation. This operational experience has been extremely valuable in view of the final LHC implementation as well as for estimating the LHC operational scenarios, most notably to establish procedures for the beam-based alignment of the collimators with respect to the circulating beam. These studies were made possible by installing in the SPS a first prototype of the LHC beam loss monitoring system. The operational experience gained at the SPS and the lessons learnt for the LHC operation are presented

Advances in evaporated solid-phase-crystallized poly-si thin-film solar cells on glass (EVA)

10.1155/2008/532351Advances in OptoElectronics2008

The CERN n_TOF facility: a unique tool for nuclear data measurement

The study of the resonant structures in neutron-nucleus cross-sections, and therefore of the compoundnucleus reaction mechanism, requires spectroscopic measurements to determine with high accuracy the energy of the neutron interacting with the material under study. To this purpose, the neutron time-of-flight facility n_TOF has been operating since 2001 at CERN. Its characteristics, such as the high intensity instantaneous neutron flux, the wide energy range from thermal to few GeV, and the very good energy resolution, are perfectly suited to perform highquality measurements of neutron-induced reaction cross sections. The precise and accurate knowledge of these cross sections plays a fundamental role in nuclear technologies, nuclear astrophysics and nuclear physics. Two different measuring stations are available at the n_TOF facility, called EAR1 and EAR2, with different characteristics of intensity of the neutron flux and energy resolution. These experimental areas, combined with advanced detection systems lead to a great flexibility in performing challenging measurement of high precision and accuracy, and allow the investigation isotopes with very low cross sections, or available only in small quantities, or with very high specific activity. The characteristics and performances of the two experimental areas of the n_TOF facility will be presented, together with the most important measurements performed to date and their physics case. In addition, the significant upcoming measurements will be introduced.Postprint (published version

(n,cp) reactions study at the n_TOF facilitty at CERN: results for the cosmological lithium problem

The Big Bang Nucleosynthesis describes the production of the lightest nuclides from deuterium to Li at the early stages of the Universe. While a general good agreement is found for most of the isotopes involved in the synthesis, a serious discrepancy between the predicted abundance of 7Li and the related experimental observations is still present. This discrepancy has been referred since several decades as Cosmological Lithium Problem. In one last attempt to find nuclear solutions to this longstanding conundrum, the 7Be(n,alpha)4He and 7Be(n,p)7Li reactions, that affect predominantly the production of 7Li via the destruction of his parent nucleus 7Be, have been studied. Here we present the 7Be(n,a)4He and 7Be(n,p)7Li reaction crosssection measurements performed at the high-resolution n_TOF facility using the time-of-flight technique and high purity samples. The result of the experiments definitely rules out neutron induced reactions as a solution to the puzzle, thus indicating that explanations have to be sought out in other Physics scenarios.Postprint (published version