Modulation Mechanism of TeV, GeV, and X-ray Emission in LS5039

The emission mechanism of the gamma-ray binary LS5039 in energy bands of TeV, GeV, and X-ray is investigated. Observed light curves in LS5039 show that TeV and GeV fluxes anticorrelate and TeV and X-ray fluxes correlate. However, such correlated variations have not been explained yet reasonably at this stage. Assuming that relativistic electrons are injected constantly at the location of the compact object as a point source, and that they lose energy only by the inverse Compton (IC) process, we calculate gamma-ray spectra and light curves by the Monte Carlo method, including the full electromagnetic cascade process. Moreover, we calculated X-ray spectra and light curves by using the resultant electron distribution. As a result, we are able to reproduce qualitatively spectra and light curves observed by HESS, Fermi, and Suzaku for the inclination angle i = 30 dig and the index of injected electron distribution p = 2.5. We conclude that TeV-GeV anticorrelation is due to anisotropic IC scattering and anisotropic gamma-gamma absorption, and that TeV-X correlation is due to the dependence of IC cooling time on orbital phases. In addition, the constraint on the inclination angle implies that the compact object in LS5039 is a black hole.Comment: 27 pages, 7 figures, published in The Astrophysical Journa

Pulsar model of the high energy phenomenology of LS 5039

Under the assumption that LS 5039 is a system composed by a pulsar rotating around an O6.5V star in a $\sim 3.9$ day orbit, we present the results of a theoretical modeling of the high energy phenomenology observed by the High Energy Stereoscopy Array (H.E.S.S.). This model (including detailed account of the system geometry, Klein-Nishina inverse Compton, $\gamma$-$\gamma$ absorption, and cascading) is able to describe well the rich observed phenomenology found in the system at all timescales, both flux and spectrum-wise.Comment: Figures and results are unchanged. Some new text and new reference

Operational beams for the LHC

The variety of beams, needed to set-up in the injectors as requested in the LHC, are reviewed, in terms of priority but also performance expectations and reach during 2015. This includes the single bunch beams for machine commissioning and measurements (probe, Indiv) but also the standard physics beams with 50 ns and 25 ns bunch spacing and their high brightness variants using the Bunch Compression Merging and Splitting (BCMS) scheme. The required parameters and target performance of special beams like the doublet for electron cloud enhancement and the more exotic 8b$\oplus$4e beam, compatible with some post-scrubbing scenarios are also described. The progress and plans for the LHC ion production beams during 2014-2015 are detailed. Highlights on the current progress of the setting up of the various beams are finally presented with special emphasis on potential performance issues across the proton and ion injector chain.Comment: Submitted for publication in a CERN Yellow Report (YR

High intensity effects of fixed target beams in the CERN injector complex

The current fixed target (FT) experiments at CERN are a complementary approach to the Large Hadron Collider (LHC) and play a crucial role in the investigation of fundamental questions in particle physics. Within the scope of the LHC Injectors Upgrade (LIU), aiming to improve the LHC beam production, the injector complex will be significantly upgraded during the second Long Shutdown (LS2). All nonLHC beams are expected to benefit from these upgrades. In this paper, we focus on the studies of the transverse instability in the Proton Synchrotron (PS), currently limiting the intensity of Time-Of-Flight (ToF) type beams, as well as the prediction of the impact of envisaged hardware modifications. A first discussion on the effect of space charge on the observed instability is also being presented

Benchmarking headtail with electron cloud instabilities observed in the LHC

After a successful scrubbing run in the beginning of 2011, the LHC can be presently operated with high intensity proton beams with 50 ns bunch spacing. However, strong electron cloud effects were observed during machine studies with the nominal beam with 25 ns bunch spacing. In particular, fast transverse instabilities were observed when attempting to inject trains of 48 bunches into the LHC for the first time. An analysis of the turn-by-turn bunch-bybunch data from the transverse damper pick-ups during these injection studies is presented, showing a clear signature of the electron cloud effect. These experimental observations are reproduced using numerical simulations: the electron distribution before each bunch passage is generated with PyECLOUD and used as input for a set of HEADTAIL simulations. This paper describes the simulation method as well as the sensitivity of the results to the initial conditions for the electron build-up. The potential of this type of simulations and their clear limitations on the other hand are discussed.Comment: 7 pages, contribution to the Joint INFN-CERN-EuCARD-AccNet Workshop on Electron-Cloud Effects: ECLOUD'12; 5-9 Jun 2012, La Biodola, Isola d'Elba, Ital

Burning mouth syndrome - causes and modern treatment methods

Introduction and purpose: Burning Mouth Syndrome (BMS) is a chronic painful disorder characterized by a burning or stinging sensation in the oral mucosa. It is a condition that affects a significant portion of the population, and its definition has recently been clarified. BMS can be divided into primary (idiopathic) or secondary forms, depending on the presence or absence of an identifiable cause. Brief description of the state of knowledge: Currently, it is estimated that BMS affects 1 in 1000 people, with women over the age of 60 being particularly susceptible. The exact causes of BMS are not well understood, but research suggests they may have a multifactorial nature, involving neuropathic, endocrinological, and psychosocial factors. BMS symptoms include oral burning, taste disturbances, dry mouth, tingling, and numbness of the tongue. Patients often experience burning sensations on the tongue, palate, gums, lower lip, and throat. In addition to physical symptoms, the condition can lead to sleep disturbances, health problems, and psychological disorders. Diagnosing BMS is challenging and time-consuming. A physician must rule out other causes of symptoms, such as oral infections or nutritional deficiencies. A detailed medical history, intraoral examination, and laboratory tests are necessary for diagnosis. Treating BMS requires the collaboration of multiple specialists, including neurologists, dentists, orofacial pain specialists, and psychologists. Summary: Burning Mouth Syndrome remains poorly understood in terms of its causes and treatment. Patients often experience not only physical discomfort but also psychological issues such as depression and anxiety. Treatment is challenging and often does not provide complete relief. Continued research into this condition is crucial to better understand its nature and find more effective treatment methods. Keywords: BMS, Burning Mouth Syndrome, stomatodynia  &nbsp

Flat Bunches with a Hollow Distribution for Space Charge Mitigation

Longitudinally hollow bunches provide one means to mitigate the impact of transverse space charge. The hollow distributions are created via dipolar parametric excitation during acceleration in CERN's Proton Synchrotron Booster. We present simulation work and beam measurements. Particular emphasis is given to the alleviation of space charge effects on the long injection plateau of the downstream Proton Synchrotron machine, which is the main goal of this study.Comment: Proceedings of International Particle Accelerator Conference 201

International Students’ Perceptions of Factors Affecting Academic Success in Post-Secondary Studies

This multiple case study examines international students’ perceptions of factors affecting academic success in post-secondary institutions in southern Ontario. The study used snowball sampling and a semi-structured interview format. Various factors in the literature, which are used as a framework for this thesis, demonstrate an influence on international students’ academic preparedness and success. They include: proficiency tests, length of time in host country, prior learning experience, acculturation, tolerance of ambiguity, and motivation. Other factors influencing students’ academic success are EAP programs, faculty and students’ own perceptions of academic preparedness and needs, international student centres, communication with domestic students, and immigration plans. The study revealed that, in addition to the listed factors, participants also identified mental health and identity as influencing factors. The study addresses the gap in existing research by providing a college setting for international students from various nationalities, in a Canadian context, studying in a range of post-secondary programs