Search results for "Field"

Etude en champ proche et champ lointain de surfaces métalliques : apport des microscopies à sonde locale à l'étude des étalons de masse

2005

Among the international system of units (SI) the kilogram is the only one which is still defined by a material artefact, the international prototype of the platinum iridium kilogram. The instability of mass standards is one of the major concerns of national metrology institutes and the subject of numerous studies. Interest in microscopic studies of surface quality of a mass has grown, as it is well known that surface roughness is a factor in determining the long-term stability of mass standards. This thesis is devoted to the study in near field and far field for determining the topography and roughness of metallic surfaces, in related with different institute, national and international met…

URBAN REGENERATION PROCESSES IN RIGA

2013

ANOTĀCIJA Pilsētas revitalizācijas process ir nozīmīga tēma mūsdienu pilsētu ģeogrāfijas pētījumos, un to raksturo dažādas formas un izpausmes. Rīgā kopš Latvijas valstiskās neatkarības atjaunošanas ir notikuši dažādi pilsētu pārmaiņu procesi. Svarīga loma šajos pilsētas pārmaiņu procesos ir pilsētas revitalizācijas procesiem, kuru rezultātā tiek revitalizētas un atkārtoti izmantotas degradētas teritorijas, tādējādi veicinot ilgtspējīgu pilsētas attīstību. Promocijas darba „Pilsētas revitalizācijas procesi Rīgā” mērķis ir izvērtēt pilsētas attīstības procesus, analizējot pilsētas revitalizācijas izpausmes Rīgā. Pētījuma ietvaros tika izstrādāta atbilstoša metodika pilsētas revitalizācijas p…

Photoluminescence properties of S2 molecule trapped in Melanophlogite

2015

We studied the photoluminescence properties of a sample of SiO2-clathrate Melanophlogite, a crystalline microporous material which is found in nature as a rare mineral. Upon β irradiation, the material displays an intense light emission under near-UV illumination. We studied in detail this optical activity by steady-state and time-resolved photoluminescence measurements as a function of temperature. The spectroscopic properties we find can be ascribed to a population of quasi-free molecules trapped within each of the two different types of cage available in the structure of this clathrate, although the spectroscopic properties of the guest molecules are affected by their interactions with t…

High-precision measurement of a low Q value for allowed β−-decay of 131I related to neutrino mass determination

2022

The ground-state-to-ground-state β−-decay 131I (7/2+) → 131Xe (3/2+) Q value was determined with high precision utilizing the double Penning trap mass spectrometer JYFLTRAP at the IGISOL facility. The Q value of this β−-decay was found to be Q = 972.25(19) keV through a cyclotron frequency ratio measurement with a relative precision of 1.6 × 10−9. This was realized using the phase-imaging ion-cyclotron-resonance technique. The new Q value is more than 3 times more precise and 2.3σ higher (1.45 keV) than the value extracted from the Atomic Mass Evaluation 2020. Our measurement confirms that the β−-decay to the 9/2+ excited state at 971.22(13) keV in 131Xe is energetically allowed with a Q va…

Search for the Decay of the Higgs Boson to Charm Quarks with the ATLAS Experiment

2018

A direct search for the standard model Higgs boson decaying to a pair of charm quarks is presented. Associated production of the Higgs and Z bosons, in the decay mode ZH→ℓ+ℓ−c¯c is studied. A data set with an integrated luminosity of 36.1  fb−1 of pp collisions at √s=13TeV recorded by the ATLAS experiment at the LHC is used. The H→c¯c signature is identified using charm-tagging algorithms. The observed (expected) upper limit on σ(pp→ZH)×B(H→c¯c) is 2.7 (3.9+2.1−1.1) pb at the 95% confidence level for a Higgs boson mass of 125 GeV, while the standard model value is 26 fb.

Beam-induced and cosmic-ray backgrounds observed in the ATLAS detector during the LHC 2012 proton-proton running period

2016

This paper discusses various observations on beam-induced and cosmic-ray backgrounds in the ATLAS detector during the LHC 2012 proton-proton run. Building on published results based on 2011 data, the correlations between background and residual pressure of the beam vacuum are revisited. Ghost charge evolution over 2012 and its role for backgrounds are evaluated. New methods to monitor ghost charge with beam-gas rates are presented and observations of LHC abort gap population by ghost charge are discussed in detail. Fake jets from colliding bunches and from ghost charge are analysed with improved methods, showing that ghost charge in individual radio-frequency buckets of the LHC can be resol…

Магнитные взаимодействия и ориентационные явления в гидродинамике намагничивающихся жидкостей

1985

Three three-letter words in three recent novels in three different languages: God, sex and joy

2017

In this article, the authors propose to analyse the ways in which religion and sexuality are related to one another in three recent novels: (1) Fransi Phillips�s Die donker god (2007), (2) Inga �olude�s Santa Biblia (2013) and (3) Michel Houellebecq�s Soumission [English translation: Submission] (2015). In each case, the novels are briefly placed within their respective literary cultures (Afrikaans, Latvian and French) in order to offer a contextually sensitive analysis. After each of the novels has been discussed related to the three related topoi of God, sex and joy, some comparative remarks are offered in conclusion.Intradisciplinary and/or interdisciplinary implications: In this contrib…