The Two-Loop Scale Dependence of the Static QCD Potential including Quark Masses

The interaction potential V(Q^2) between static test charges can be used to define an effective charge $\alpha_V(Q^2)$ and a physically-based renormalization scheme for quantum chromodynamics and other gauge theories. In this paper we use recent results for the finite-mass fermionic corrections to the heavy-quark potential at two-loops to derive the next-to-leading order term for the Gell Mann-Low function of the V-scheme. The resulting effective number of flavors $N_F(Q^2/m^2)$ in the $\alpha_V$ scheme is determined as a gauge-independent and analytic function of the ratio of the momentum transfer to the quark pole mass. The results give automatic decoupling of heavy quarks and are independent of the renormalization procedure. Commensurate scale relations then provide the next-to-leading order connection between all perturbatively calculable observables to the analytic and gauge-invariant $\alpha_V$ scheme without any scale ambiguity and a well defined number of active flavors. The inclusion of the finite quark mass effects in the running of the coupling is compared with the standard treatment of finite quark mass effects in the $\bar{MS}$ scheme.Comment: 27 pages, 13 figure

On-shell neutral Higgs bosons in the NMSSM with complex parameters

The Next-to-Minimal Supersymmetric Standard model (NMSSM) appears as an interesting candidate for the interpretation of the Higgs-measurement at the LHC and as a rich framework embedding physics beyond the Standard Model. We consider the renormalization of the Higgs sector of this model in its $\mathcal{CP}$-violating version, and propose a renormalization scheme for the calculation of on-shell Higgs masses. Moreover, the connection between the physical states and the tree-level ones is no longer trivial at the radiative level: a proper description of the corresponding transition thus proves necessary in order to calculate Higgs production and decays at a consistent loop order. After discussing these formal aspects, we compare the results of our mass calculation to the output of existing tools. We also study the relevance of the on-shell transition-matrix in the example of the $h_i \to \tau^+ \tau^-$ width. We find deviations between our full prescription and popular approximations that can exceed $10\%$.Comment: 28 pages, 11 figure

From democracy to stability : European Union Democracy promotion in Tunisia 1995-2007

Very little scholarship has been published on politics in Tunisia in the last two decades, resulting in scant coverage of the country’s political relations with the European Union (EU). Likewise, few studies of the EU’s democracy promotion and Mediterranean policies have provided any in-depth analysis of Tunisia. Meanwhile, much has been made by scholars of role played by democracy promotion in the EU’s foreign policy, particularly focusing on understandings of the Union as a ‘normative power’ or as an advocate of the ‘democratic peace theory’. By assessing EU democracy promotion in Tunisia, this thesis argues that democracy promotion has become a predominantly functional part of this foreign policy; its principal role being a means of realising the Union’s principal objectives of achieving security and stability for Europeans. By analysing the discourse of actors involved with the EU’s democracy promotion, the thesis traces a shift in EU policy from a more normative position in the mid-1990s to a more realist and securitised one since the turn of the twenty-first century. Tunisia has evolved over the last two centuries as a state strongly committed to European-influenced socio-economic reforms, but reforms which have led to little political contestability and few changes in government. However, as the EU forged a new approach to its Mediterranean neighbours, it established the promotion of democracy in its neighbours as an integral part of its foreign and security policies. Democracy was to be promoted in Tunisia within multilateral and holistic policy frameworks, such as the Euro-Mediterranean Partnership, and by a range of methods that encourage reform of many levels of the region’s societies. Yet it appears that these reforms are failing to deliver the political reforms they once promised. Furthermore, democracy is gradually slipping off the EU’s agenda, and its policy objectives converge with those of the Tunisian government as security concerns come to dominate its policy discourses. In the Tunisian context at least, democracy is a purely utilitarian device used to achieve security. When that security already exists, democracy loses its utility, and fades from its once prominent place in the EU policy in Tunisia.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

GNSS Receiver Based Navigation of Satellites in Geotransfer Orbits

An open source simulator for a global navigation satellite system (GNSS) based onboard navigation of satellites is presented. The structure and building blocks of the simulator, as well as the data sets included with the simulator, are described. To illustrate the application of the simulator, it is used to evaluate the navigation performance that can be expected by a GNSS-receiver based navigation system on board a satellite in a geotransfer orbit. Three phases of the geotransfer orbit are analyzed, first an early orbit phase where the satellite has a highly eccentric orbit, secondly an intermediate orbit phase where the altitude of the satellite periodically is close to that of the GNSS-satellites, and fi- nally a late orbit phase, when the satellite is almost in a geostationary orbit, but has not yet rotated into its final attitude. The simulations show that with a GNSS-receiver with an acquisition and tracking threshold of 27 [dB ? Hz] and two high gain antennas, the root mean square position and velocity error can throughout all three orbit phases be kept below 1000 [m] and 30 [mm/s], respectively.QC 20151217</p

Mars Orbiting Plasma Surveyor (MOPS)

Mars Orbiting Plasma Surveyor (MOPS) is a microsatellite mission focused on studies of the near -Mars environment and the planet - solar wind interaction. The recent findings by the ESA Mars Express mission further highlighted the complexity of the processes taking place at the planet resulting from the solar wind interaction that strongly affect the planet's atmosphere. However, despite many previous Martian missions carrying different types of space plasma experiments, a comprehensive investigation including simultaneous measurements of particles, fields, and waves has never been performed. We consider a spinning spacecraft of a wet mass of 76.1 kg with a 9.7 kg payload, which can “hitchhike” on another platform until Mars orbit insertion, and then be released into a suitable orbit. The spacecraft design is based on the experience gained in very successful Swedish space plasma missions, Viking, Freja, Astrid-1, and Astrid-2. In the present mission design, the MOPS spacecraft is equipped with its own 1m high gain antenna for direct communication with the Earth. The payload includes a wave experiment with wire booms, magnetometer with a rigid boom, Langmuir probes, electron and ion energy spectrometers and an ion mass analyzer. An energetic neutral atom imager and an UV photometer may complete the core payload. One of the proposed scenarios is piggy - backing on the Russian Phobos - Grunt mission to be launched to Mars in 2011.QC 2012032

Effects of volatile oils on microorganisms

Darba mērķis ir noskaidrot apelsīnu, melisas, eikaliptu un tējas koka ēterisko eļļu ietekmi uz mikroorganismu (Staphylococcus aureus,Candida albicans, Escherichia coli) augšanu agara un triptona sojas šķidrajā barotnē. Eļļu efekti tika izvērtēti pēc to ietekmes uz mikroorganismu tīrkultūru augšanu in vitro un uz mikroorganismiem uztriepes no rokām. Iegūtie rezultāti liecina, ka visām šajā darbā pētītām ēteriskām eļļām piemīt antimikrobiāla darbība, bet visaktīvākā bija tējas koka eļļa. Eļļu efekti tika izvērtēti pēc mikroorganismu koloniju skaita samazinājuma, audzējot ēterisko eļļu klātbūtnē. Pētījumi parādīja, ka antimikrobiālais efekts ir atkarīgs no tējas koka ēteriskās eļļas koncentrācijas, t.i. izaugušo mikroorganismu koloniju skaits ir apgriezti proporcionāls ēteriskās eļļas koncentrācijai.The aim of work is to define influence of orange, Narrow-leaved Tea-tree, eucalypt, Melissa plants to microorganisms (Staphylococcus aureus, Candida albicans, Escherichia coli) growth, in breeding of agara and triptona soja. Oils effects are evaluated by influence on microorganisms pure culture growth in vitro and on microorganisms wash away from hands. Obtained results confirm, that all volatile oils studied in this work have anti microbe properties, but the most ective was tea tree oil. Oils efects were evaluated by microorganisms colony decrease, growing it in one environment with volatile oils. Researches shows that anti microbe effect depend from tea tree volatile oils concentration; microorganism’s colony growth is inversely proportional to volatile oils concentration

SMART-1 lunar mission: Operations close to moon impact

SMART-1 is the first of the European Space Agency's Small Missions for Advanced Research in Technology. It demonstrated orbit raising from geostationary transfer orbit to the Moon using solar-electric propulsion. In November 2004 SMART-1 successfully manoeuvred into Moon orbit. Since February 2005 SMART-1 has been in its operational orbit performing scientific operations that were interrupted only by a one-month reboost phase in September 2005 to re-optimize the orbit. Without orbit control, natural degradation of the orbit causes the spacecraft to impact the Moon on the far side by midaugust 2006. With orbit control, the impact date and location can be influenced such an Earth observation campaign can be organized to observe it. This paper will outline how the ground segment at ESOC (Darmstadt, Germany) and the ESA Directorate of Scientific Programmes at ESTEC (Noordwijk, The Netherlands) are preparing for operations close to Moon impact. It will highlight how the orbit evolves towards the end of the mission, discuss how the different spacecraft sub-systems are affected by the changing orbit and close proximity of the Moon, and suggest ideas for special operations at low altitude and around the time of impact. © 2006 by European Space Agency (ESA).link_to_subscribed_fulltex