Vibrations on pulse tube based Dry Dilution Refrigerators for low noise measurements

Dry Dilution Refrigerators (DDR) based on pulse tube cryo-coolers have started to replace Wet Dilution Refrigerators (WDR) due to the ease and low cost of operation. However these advantages come at the cost of increased vibrations, induced by the pulse tube. In this work, we present the vibration measurements performed on three different commercial DDRs. We describe in detail the vibration measurement system we assembled, based on commercial accelerometers, conditioner and DAQ, and examined the effects of the various damping solutions utilized on three different DDRs, both in the low and high frequency regions. Finally, we ran low temperature, pseudo-massive (30 and 250 g) germanium bolometers in the best vibration-performing system under study and report on the results

Low-energy neutrinos at off-axis from a standard beta-beam

We discuss a scenario to extract up to 150 MeV neutrinos at a standard beta-beam facility using one and two detectors off-axis. In particular we show that the high-energy component of the neutrino fluxes can be subtracted through a specific combination of the response of two off-axis detectors. A systematic analysis of the neutrino fluxes using different detector geometries is presented, as well as a comparison with the expected fluxes at a low-energy beta-beam facility. The presented option could offer an alternative way to perform low-energy neutrino experiments.Comment: 9 pages, 6 figure

Budheting and accounting reforms within the public financial mangement framework: the Portuguese case

This chapter discusses the role of budgetary and accounting systems within the Public Financial Management (PFM) framework. Additionally, it describes the reforms nowadays taking place in Portugal, namely taking into consideration new budgetary and accounting systems starting implementation, explaining how they are included in a broader reform of the PFM structure. PFM implies governments to use integrated systems to allocate funds and control spending execution, involving a wide approach, including policies design and internal and external auditing assessment systems. Also accounting reforms are essential to achieve PFM purposes, namely applying accrual basis to prepare and report financial statements under the international accounting standards approach (Lawson, 2015). In Portugal, in the latter years, within the public sector, there has been a great fragmentation of accounting and reporting systems applied to different entities, raising inconsistencies and creating difficulties when trying to assess the Whole of Government financial condition. In this context, the Portuguese government, under strong recommendations of the loaners (because of the financial assistance through Troika), started a set of PFM reforms, including changing the existing public sector accounting system by adopting the International Public Sector Accounting Standards (IPSAS) as the benchmark (Nogueira et al., 2017). Accordingly, in 2015 relevant legislation was issued: the new Budgetary Framework Law (LEO – Law 151/2015) and the new System of Accounting Standards for Public Administrations (SNC-AP – Law-decree 192/2015). In 2016 a unit to assure the implementation of these new budgetary and accounting systems was created, designated as UniLEO. According to Viana (2017), the mission of this unit configures a true PFM reform. Hereafter, the chapter is organised in four sections. Section 2 addresses the harmonization problems related to accounting reforms in financial accounting and their inclusion in a broader reform process under PFM objectives. Section 3 explains the benefits of integrating budgetary and financial accounting innovations in a broader PFM reform, also highlighting how PFM systems outputs could be used to change the EU convergence criteria framework. The Portuguese PFM reforms, including budgeting and accounting changes, presently being implemented, are described in Section 4. In Section 5 some final marks and conclusions are synthesised, highlighting the Portuguese PFM reforms as a reference at an international level.info:eu-repo/semantics/acceptedVersio

Modelagem do nível superficial e vulnerabilidade dos aquíferos de Sergipe.

A aplicação de sistemas de informações geográficas é uma ferramenta que permite a análise das características ambientais a fim de possibilitar a sua modelagem e proporcionar a gestão ambiental. Esse estudo objetivou criar um modelo espacial do nível superficial do lençol freático para o Estado de Sergipe por meio da utilização de sistemas de informação geográfica, analisando o parâmetro de profundidade do método GOD a fim de servir como base para analisar a vulnerabilidade dos aquíferos quanto à sua contaminação. Para a execução do trabalho foi utilizado o ArcGIS e os dados do Atlas Digital de Recursos Hídricos de Sergipe. Foi criado o Modelo Digital de Elevação referente às profundidades dos poços cadastrados e da superfície do terreno, feita a subtração, foi obtida a altimetria dos aquíferos e adotado o método GOD para indicar o parâmetro de profundidade e o grau de vulnerabilidade do aquífero. De acordo com os resultados, verificou-se que grande parte dos aquíferos encontra-se em profundidades acima de 50 m, o que indica um menor risco de contaminação e que existe um padrão quanto à altimetria do nível freático do litoral para o interior do Estado

Amostragem das pragas do algodoeiro com auxilio de ficha pictografica.

A ficha pctografica; Implantacao do metodo.bitstream/item/33300/1/CNPA-DOCUMENTOS-06-AMOSTRAGEM-DAS-PRAGAS-DO-ALGODOEIRO-COM-AUXILIO-DE-FICHA-PICTOGRAFICA-FL-02978.pd

Spectra and Symmetry in Nuclear Pairing

We apply the algebraic Bethe ansatz technique to the nuclear pairing problem with orbit dependent coupling constants and degenerate single particle energy levels. We find the exact energies and eigenstates. We show that for a given shell, there are degeneracies between the states corresponding to less and more than half full shell. We also provide a technique to solve the equations of Bethe ansatz.Comment: 15 pages of REVTEX with 2 eps figure

320g Ionization-Heat Cryogenic Detector for Dark Matter Search in the EDELWEISS Experiment

The EDELWEISS experiment used in 2001 a 320g heat-and-ionization cryogenic Ge detector operated in a low-background environment in the Laboratoire Souterrain de Modane for direct WIMP detection. This detector presents an increase of more than 4 times the mass of previous detectors. Calibrations of this detector are used to determine its energy resolution and fiducial volume, and to optimize the detector design for the 1kg phase of the EDELWEISS-I experiment. Analysis of the calibrations and characteristics of a first series of 320g-detectors are presented.Comment: 4 pages, 3 figure

Synchrotron radiation photoionization mass spectrometry of laser ablated species

The present paper describes an experimental apparatus suitable to create and study free clusters by combining laser ablation and synchrotron radiation. First tests on sulfur samples, S, showed the production, through laser ablation, of neutral Sn clusters (n = 1–8). These clusters were ionized using synchrotron radiation at photon energies from 160 eV to 175 eV, across the S 2p core edge. The feasibility of such combined ablation–synchrotron radiation experiments is demonstrated, opening new possibilities on the investigation of free clusters and radical

Influência da temperatura de armazenamento na qualidade sensorial do pinhão.

Resumo