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Search for supersymmetry in events with a photon, a lepton, and missing transverse momentum in proton-proton collisions at √s=13 TeV
No full textResults of a search for supersymmetry are presented using events with a photon, an electron or muon, and large missing transverse momentum. The analysis is based on a data sample corresponding to an integrated luminosity of 35.9 fb(-1) of proton-proton collisions at 13 TeV, produced by the LHC and collected with the CMS detector in 2016. Theoretical models with gauge-mediated supersymmetry breaking predict events with photons in the final state, as well as electroweak gauge bosons decaying to leptons. Searches for events with a photon, a lepton, and missing transverse momentum are sensitive probes of these models. No excess of events is observed beyond expectations from standard model processes. The results of the search are interpreted in the context of simplified models inspired by gauge-mediated supersymmetry breaking. These models are used to derive upper limits on the production cross sections and set lower bounds on masses of supersymmetric particles. Gaugino masses below 930 GeV are excluded at the 95% confidence level in a simplified model with electroweak production of a neutralino and chargino. For simplified models of gluino and squark pair production, gluino masses up to 1.75 TeV and squark masses up to 1.43 TeV are excluded at the 95% confidence level
Studies of beauty suppression via nonprompt D0 mesons in Pb-Pb collisions at √sNN=5.02TeV
No full textPubMed: 31386524The transverse momentum spectra of D-0 mesons from b hadron decays are measured at midrapidity (vertical bar y vertical bar D-0 yield is found to be suppressed in the measured p(T) range from 2 to 100 GeV/c as compared to pp collisions. The suppression is weaker than that of prompt D-0 mesons and charged hadrons for p(T) around 10 GeV/c. While theoretical calculations incorporating partonic energy loss in the quark-gluon plasma can successfully describe the measured B -> D-0 suppression at higher p(T), the data show an indication of larger suppression than the model predictions in the range of 2 < p(T) < 5 GeV/c
Search for anomalous triple gauge couplings in WW and WZ production in lepton + jet events in proton-proton collisions at √s = 13 TeV
No full textA search is presented for three additional operators that would lead to anomalous WW? or WWZ couplings with respect to those in the standard model. They are constrained by studying events with two vector bosons; a W boson decaying to e? or ??, and a W or Z boson decaying hadronically, reconstructed as a single, massive, large- radius jet. The search uses a data set of proton-proton collisions at a centre-of-mass energy of 13 TeV, recorded by the CMS experiment at the CERN LHC in 2016, and corresponding to an integrated luminosity of 35.9 fb?1. Using the reconstructed diboson invariant mass, 95% confidence intervals are obtained for the anomalous coupling parameters of ?1.58 < cWWW/?2< 1.59 TeV?2, ?2.00 < cW/?2< 2.65 TeV?2, and ?8.78 < cB/?2< 8.54 TeV?2, in agreement with standard model expectations of zero for each parameter. These are the strictest bounds on these parameters to date. [Figure not available: see fulltext.]. © 2019, The Author(s)
Search for low-mass quark-antiquark resonances produced in association with a photon at √s=13 TeV
No full textPubMed: 31868480A search for narrow low-mass resonances decaying to quark-antiquark pairs is presented. The search is based on proton-proton collision events collected at 13 TeV by the CMS detector at the CERN LHC. The data sample corresponds to an integrated luminosity of 35.9 fb(-1), recorded in 2016. The search considers the case where the resonance has high transverse momentum due to initial-state radiation of a hard photon. To study this process, the decay products of the resonance are reconstructed as a single large-radius jet with two-pronged substructure. The signal would be identified as a localized excess in the jet invariant mass spectrum. No evidence for such a resonance is observed in the mass range 10 to 125 GeV. Upper limits at the 95% confidence level are set on the coupling strength of resonances decaying to quark pairs. The results obtained with this photon trigger strategy provide the first direct constraints on quark-antiquark resonance masses below 50 GeV obtained at a hadron collider
Search for long-lived particles using delayed photons in proton-proton collisions at √s=13 TeV
No full textA search for long-lived particles decaying to photons and weakly interacting particles, using protonproton collision data at root s = 13 TeV collected by the CMS experiment in 2016-2017 is presented. The data set corresponds to an integrated luminosity of 77.4 fb(-1). Results are interpreted in the context of supersymmetry with gauge-mediated supersymmetry breaking, where the neutralino is long-lived and decays to a photon and a gravitino. Limits are presented as a function of the neutralino proper decay length and mass. For neutralino proper decay lengths of 0.1, 1, 10, and 100 m, masses up to 320, 525, 360, and 215 GeV are excluded at 95% confidence level, respectively. We extend the previous best limits in the neutralino proper decay length by up to one order of magnitude, and in the neutralino mass by up to 100 GeV
Atomistic insights on the influence of pre-oxide shell layer and size on the compressive mechanical properties of nickel nanowires
No full textWe used ReaxFF reactive molecular dynamics simulations to systematically investigate the effects of a pre-oxide shell layer on the mechanical properties of [001]-oriented nickel (Ni) nanowires (NWs) under the uniaxial compressive loading at room temperature. The pristine Ni NWs are considered as references to compare the mechanical properties of the oxide-coated NWs. We found that the mechanical properties of pristine Ni NWs under uniaxial compression are sensitive to both the diameter of the NWs and the pre-oxide shell layer, and their combined effect determines the overall stress and strain behaviors. The compressive strength of the pristine NWs decreases significantly with the decreasing diameter. We observe that the native defected amorphous pre-oxide shell layer with similar to 1.0 nm thickness leads to a lowering of the mechanical compressive resistivity of NWs and causes additional softening. Oxide-coated NWs exhibit a lesser size-dependent unique properties and a lower overall yield strength compared to their pristine counterparts. The reduction of the mechanical compressive yield stress and strain with the decreasing diameter is due to the substantial changes in plastic flow as well as correlated with the existence of the pre-oxide shell layer as compared to its pristine counterpart. Particularly, pre-oxide shell layers have pronounced effects on the initiation of initial dislocations to onset plastic deformation and consequently on the overall plastic response. Published under license by AIP Publishing
Search for single production of vector-like quarks decaying to a top quark and a W boson in proton-proton collisions at √s= TeV
No full textPubMed: 30814908A search is presented for the single production of vector-like quarks in proton-proton collisions at TeV. The data, corresponding to an integrated luminosity of 35.9fb-1, were recorded with the CMS experiment at the LHC. The analysis focuses on the vector-like quark decay into a top quark and a W boson, with one muon or electron in the final state. The mass of the vector-like quark candidate is reconstructed from hadronic jets, the lepton, and the missing transverse momentum. Methods for the identification of b quarks and of highly Lorentz boosted hadronically decaying top quarks and W bosons are exploited in this search. No significant deviation from the standard model background expectation is observed. Exclusion limits at 95% confidence level are set on the product of the production cross section and branching fraction as a function of the vector-like quark mass, which range from 0.3 to 0.03pb for vector-like quark masses of 700 to 2000GeV. Mass exclusion limits up to 1660GeV are obtained, depending on the vector-like quark type, coupling, and decay width. These represent the most stringent exclusion limits for the single production of vector-like quarks in this channel
The sustainability of an urban ritual in the collective memory: Bergama Kermesi
No full textBergama Festival, locally known as Bergama Kermesi, is an annual festival which dates back to 22 May 1937 in the city. It came into existence as a result of Ataturk's intention to introduce this, an extraordinary town with its historical and cultural properties, and promote it internationally. The Festival is an important element in the collective memory of the city. Initially, it was a civic event, a device in the formation process of the Turkish Republic. However, now, it is a civil event for national and international representatives, and a festival that allows locals and guests from different social, economic, and cultural backgrounds to mix freely and equally for a certain period. In the course of the Festival, the public buildings and the open spaces of the town become places of activity and entertainment. Parks, stadiums, the town square, and streets function as spaces for a variety of activities. Looking back at its 81-year history, one can notice some important changes in the Festival's cultural and social practices, from an earlier state-dominated character into the current more publicly oriented one. This article studies the change of Bergama Festival as an invented tradition' into an element of the collective memory in town from the perspective of different public affairs that it introduces. In this regard, the article will also show how an urban ritual can maintain its sustainability by keeping itself fresh in the social life
Farklı yüzey pürüzlülüklerine sahip silika nanopartiküllerin yüzey elektrik yükü üzerine araştırmalar
No full textThesis (Master)--Izmir Institute of Technology, Mechanical Engineering, Izmir, 2019Includes bibliographical references (leaves: 58-65)Text in English; Abstract: Turkish and EnglishSilica nanoparticles have been receiving more attention from diverse research areas recently due to their significant physical properties such as large pore volume and high internal surface area, colloidal stability, high biocompatibility, and tunable pore sizes. These silica nanoparticles are great candidates for drug delivery applications because they can transport a large amount of drugs into selective organs and tissues due to their high surface area and large pore volume. However, there are important drug delivery mechanisms that need to be understood properly such as cellular uptake, endosomal escape, drug loading and release, and crossing physical barriers. Physicochemical properties of nanoparticles (size, shape, surface charge, or surface chemistry) are important for understanding these mechanisms in order to develop successful drug delivery applications. This research investigates how these surface charge properties change with different particle, pore diameters, roughness structure on the nanoparticle surface, and different temperature and solution conditions. Also, we investigate how the surface charging behavior of rough nanoparticles interacts with a flat plate. Rough nanoparticles and their interactions with surfaces theoretical assumptions can be wrong and ionic distribution can show variation locally. In order to calculate ionic distribution and surface charge properties in these systems, proper equations and boundary conditions were employed. The charge regulation model was used as a boundary condition because of the electric double layer overlap effect. Results showed that there was a considerable variation on surface charge properties due to the roughness structure with different roughness and particle sizes and temperature difference.Silika nanopartiküller yüksek iç yüzey alanı ve geniş gözenek hacmi, yüksek biyouyumluluk
ve kolloidal kararlılık gibi avantajlı fiziksel özellikleri ile çeşitli biyomedikal
uygulamalar için uygun adaylardır. Özellikle ilaç iletimi uygulamalarında yüksek ilaç
taşıma kapasitesi sayesinde sıklıkla tercih edilirler. Silika nanopartiküllerin yüzey elektrik
şarjı bu uygulamaların verimliliği açısından çok belirleyicidir. Çünkü ilaç iletimi
uygulamaları sırasında görülen bazı hüçre içi mekanizmalar nanopartikülün yüzey
elektrik şarjına bağlıdır. Örnek olarak, ilaç iletiminin başarısını fazlasıyla etkileyen
hücresel alım mekanizması nanopartikülün yüzey elektrik şarjı ve boyutları ile doğrudan
ilişkilidir. Ayrıca ilaç iletimi sırasında görülen en önemli sorunlardan birisi de endozomal
kaçışın sağlanmasıdır. Nanopartikül yüzey elektrik şarjı ve boyutunun endozomal kaçışın
sağlanmasında etkili olduğunu gösteren çalışmalar vardır. Bu nedenle yüzeyi pürüzlü
nanoparçacıkların yüzey elektrik şarjının incelenmesi önemli bir konu oluşturmaktadır.
Bu çalışmada yüzeyi gözenekli nanopartiküllerin farklı pürüz ve parçacık çapları, farklı
solüsyon özellikleri, sıcaklık değişimi ve düz bir yüzey ile etkileşimi sonucunda oluşan
yüzey elektrik şarjı davranışı incelenmiştir. Yüzeyi pürüzlü nanopartiküllerin yüzeyinde
oluşan iyonik dağılım ve elektrik şarjı davranışının doğru olarak hesaplanabilmesi için
uygun denklemler ve sınır şartları seçilmiştir. Elektriksel çift tabakaların çakışması
etkisinden dolayı sınır koşulu olarak kullanılan yük regülasyon modeli nanopartikül
yüzeyinde sınır şartı olarak seçilmiştir. Sonuçlar, farklı pürüzlülük ve parçacık ebatları ve
sıcaklık farkına sahip pürüzlülük yapısı nedeniyle yüzey yükü özelliklerinde önemli bir
değişiklik olduğunu göstermektedir.TUBITAK (118M710
Interior plastering of Ottoman bath buildings
No full textOttoman baths were peculiar buildings with their function in community life, architectural characteristics and material use. Their interior spaces were exposed to high humidity and temperatures that made the building structure vulnerable to physical, chemical, physicochemical and biological degradations. Plasters used on the interior wall surfaces were the most important agents to protect the structure from deterioration and provide durability. This study aims to exhibit the plaster characteristics of Çinili Bath in İstanbul which was an outstanding example of Ottoman baths and built by Great Architect Sinan. Basic physical properties, raw material compositions, mineralogical, microstructural and hydraulic properties of original brick-lime plasters called as horasan (khorasan) plasters used on the walls were determined by XRF, XRD, SEM-EDS and TGA. Multilayered plaster application together with the use of glazed tiles were observed on the wall surfaces of all interior spaces. The plasters were produced from pure lime and pozzolanic crushed brick or tile aggregates and hydraulic because of the pozzolanic properties of aggregates. They are stiff, compact and durable in hot and humid conditions of bath buildings due to their self-healing properties and the formation of calcium silicate hydrates and calcium aluminate hydrates at the lime-brick interfaces and in the pores of the pozzolanic brick aggregates by the reaction of lime. Characteristics of brick aggregates were compared with the construction bricks used in the building. Their chemical and mineralogical compositions revealed that the aggregates had not been produced from construction bricks. All the results indicated that brick-lime plasters were the most suitable materials for bath buildings to protect the structure from the effect of water. © 2019 The Author