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Nanoconfined circular and linear DNA - equilibrium conformations and unfolding kinetics
https://cds.cern.ch/record/2150619
Studies of circular DNA confined to nanofluidic channels are relevant both from a fundamental polymer-physics perspective and due to the importance of circular DNA molecules in vivo. We here observe the unfolding of DNA from the circular to linear configuration as a light-induced double strand break occurs, characterize the dynamics, and compare the equilibrium conformational statistics of linear and circular configurations. This is important because it allows us to determine to which extent existing statistical theories describe the extension of confined circular DNA. We find that the ratio of the extensions of confined linear and circular DNA configurations increases as the buffer concentration decreases. The experimental results fall between theoretical predictions for the extended de Gennes regime at weaker confinement and the Odijk regime at stronger confinement. We show that it is possible to directly distinguish between circular and linear DNA molecules by measuring the emission intensity from the DNA. Finally, we determine the rate of unfolding and show that this rate is larger for more confined DNA, possibly reflecting the corresponding larger difference in entropy between the circular and linear configurations.Alizadehheidari, MWerner, ENoble, CReiter-Schad, MNyberg, L KFritzsche, JMehlig, BTegenfeldt, J OAmbjörnsson, TPersson, FWesterlund, FWed, 04 May 2016 06:07:17 GMT03 May 2016arXiv:1605.00886https://cds.cern.ch/record/2150619['arXiv:1605.00886']arXiv:1605.00886Conjugated liquid layers driven by the short-wavelength B\'enard-Marangoni instability: experiment and numerical simulation
https://cds.cern.ch/record/2150618
The coupled dynamics of two conjugated liquid layers of disparate thicknesses, which coat a solid substrate and are subjected to a transverse temperature gradient, is investigated. The upper liquid layer evolves under the short-wavelength (SW) B\'enard-Marangoni (BM) instability, whereas the lower, much thinner film undergoes a shear-driven long-wavelength deformation. Although the lubricating film should reduce the viscous stresses acting on the up to one hundred times thicker upper layer by only 10%, it is found that the critical Marangoni number of marginal stability may be as low as if a stress-free boundary condition were applied at the bottom of the upper layer, i.e. much lower than the classical value of 79.6 known for a single film. Furthermore, it is experimentally verified that the deformation of the liquid-liquid interface, albeit small, has a non-negligible effect on the temperature distribution along the liquid-gas interface of the upper layer. This stabilizes the hexagonal pattern symmetry towards external disturbances and indicates a two-way coupling of the different layers. The experiments also demonstrate how convection patterns formed in a liquid film can be used to pattern a second conjugated film. The experimental findings are verified by a numerical model of the coupled layers.Nejati, ImanDietzel, MathiasHardt, SteffenWed, 04 May 2016 06:07:17 GMT03 May 2016arXiv:1605.00885https://cds.cern.ch/record/2150618['arXiv:1605.00885']arXiv:1605.00885Short-Time Elasticity of Polymer Melts: Tobolsky Conjecture and Heterogeneous Local Stiffness
https://cds.cern.ch/record/2150616
An extended Molecular-Dynamics study of the short-time "glassy" elasticity exhibited by a polymer melt of linear fully-flexible chains above the glass transition is presented. The focus is on the infinite-frequency shear modulus $G_\infty$ manifested in the picosecond time scale and the relaxed plateau $G_p$ reached at later times and terminated by the structural relaxation. The local stiffness of the interactions with the first neighbours of each monomer exhibits marked distribution with average value given by $G_\infty$. In particular, the neighbourhood of the end monomers of each chain are softer than the inner monomers, so that $G_\infty$ increases with the chain length. $G_p$ is not affected by the chain length and is largely set by the non-bonding interactions, thus confirming for polymer melts the conjecture formulated by Tobolsky for glassy polymers.Bernini, SLeporini, DWed, 04 May 2016 06:07:17 GMT03 May 2016arXiv:1605.00878https://cds.cern.ch/record/2150616['arXiv:1605.00878']arXiv:1605.00878Weak links between fast mobility and local structure in molecular and atomic liquids
https://cds.cern.ch/record/2150614
We investigate by Molecular-Dynamics simulations the fast mobility - the rattling amplitude of the particles temporarily trapped by the cage of the neighbors - in mildly supercooled states of dense molecular (linear trimers) and atomic (binary mixtures) liquids. The mixture particles interact by the Lennard-Jones potential. The non-bonded particles of the molecular system are coupled by the more general Mie potential with variable We investigate by Molecular-Dynamics simulations the fast mobility - the rattling amplitude of the particles temporarily trapped by the cage of the neighbors - in mildly supercooled states of dense molecular (linear trimers) and atomic (binary mixtures) liquids. The mixture particles interact by the Lennard-Jones potential. The non-bonded particles of the molecular system are coupled by the more general Mie potential with variable repulsive and attractive exponents in a range which is characteristic of small $n$-alkanes and $n$-alcohols. Possible links between the fast mobility and the geometry of the cage (size and shape) are searched. The correlations on a per-particle basis are rather weak. Instead, if one groups either the particles in fast-mobility subsets or the cages in geometric subsets, the increase of the fast mobility with both the size and the asphericity of the cage is revealed. The observed correlations are weak and differ in states with equal relaxation time. Local forces between a tagged particle and the first-neighbor shell do not correlate with the fast mobility in the molecular liquid. It is concluded that the cage geometry alone is unable to provide a microscopic interpretation of the known, universal link between the fast mobility and the slow structural relaxation. We suggest that the particle fast dynamics is affected by regions beyond the first neighbours, thus supporting the presence of collective, extended fast modes.Bernini, SPuosi, FLeporini, DWed, 04 May 2016 06:07:17 GMT03 May 2016arXiv:1605.00867https://cds.cern.ch/record/2150614['arXiv:1605.00867']arXiv:1605.00867Cage rattling does not correlate with the local geometry in molecular liquids
https://cds.cern.ch/record/2150611
Molecular-dynamics simulations of a liquid of short linear molecules have been performed to investigate the correlation between the particle dynamics in the cage of the neighbors and the local geometry. The latter is characterized in terms of the size and the asphericity of the Voronoi polyhedra. The correlation is found to be poor. In particular, in spite of the different Voronoi volume around the end and the inner monomers of a molecule, all the monomers exhibit coinciding displacement distribution when they are caged (as well as at longer times during the structural relaxation). It is concluded that the fast dynamics during the cage trapping is a non-local collective process involving monomers beyond the nearest neighbours.Bernini, SPuosi, FLeporini, DWed, 04 May 2016 06:07:16 GMT03 May 2016arXiv:1605.00846https://cds.cern.ch/record/2150611['arXiv:1605.00846']arXiv:1605.00846Optical atomic magnetometry for magnetic induction tomography of the heart
https://cds.cern.ch/record/2150610
We report on the use of radio-frequency optical atomic magnetometers for magnetic induction tomography measurements. We demonstrate the imaging of dummy targets of varying conductivities placed in the proximity of the sensor, in an unshielded environment at room-temperature and without background subtraction. The images produced by the system accurately reproduce the characteristics of the actual objects. Furthermore, we perform finite element simulations in order to assess the potential for measuring low-conductivity biological tissues with our system. Our results demonstrate the feasibility of an instrument based on optical atomic magnetometers for magnetic induction tomography imaging of biological samples, in particular for mapping anomalous conductivity in the heart.Deans, CameronMarmugi, LucaHussain, SarahRenzoni, FerruccioWed, 04 May 2016 06:07:16 GMT03 May 2016arXiv:1605.00839https://cds.cern.ch/record/2150610['arXiv:1605.00839']arXiv:1605.00839Geometric Metasurface Fork Gratings for Vortex Beam Generation and Manipulation
https://cds.cern.ch/record/2150609
In recent years, optical vortex beams possessing orbital angular momentum have caught much attention due to their potential for high capacity optical communications. This capability arises from the unbounded topological charges of orbital angular momentum (OAM) that provides infinite freedoms for encoding information. The two most common approaches for generating vortex beams are through fork diffraction gratings and spiral phase plates. While realization of conventional spiral phase plate requires complicated 3D fabrication, the emerging field of metasurfaces has provided a planar and facile solution for generating vortex beams of arbitrary orbit angular momentum. Here we realize a novel type of geometric metasurface fork grating that seamlessly combine the functionality of a metasurface phase plate for vortex beam generation, and that of a linear phase gradient metasurface for controlling the wave propagation direction. The metasurface fork grating is therefore capable of simultaneously controlling both the spin and the orbital angular momentum of light.Chen, ShumeiCai, YuanLi, GuixinZhang, ShuangCheah, Kok WaiWed, 04 May 2016 06:07:16 GMT03 May 2016arXiv:1605.00831https://cds.cern.ch/record/2150609['arXiv:1605.00831']arXiv:1605.00831Performance of the finite volume method in solving regularised Bingham flows: inertia effects in the lid-driven cavity flow
https://cds.cern.ch/record/2150582
We extend our recent work on the creeping flow of a Bingham fluid in a lid-driven cavity, to the study of inertial effects, using a finite volume method and the Papanastasiou regularisation of the Bingham constitutive model [J. Rheology 31 (1987) 385-404]. The finite volume method used belongs to a very popular class of methods for solving Newtonian flow problems, which use the SIMPLE algorithm to solve the discretised set of equations, and have matured over the years. By regularising the Bingham constitutive equation it is easy to extend such a solver to Bingham flows since all that this requires is to modify the viscosity function. This is a tempting approach, since it requires minimum programming effort and makes available all the existing features of the mature finite volume solver. On the other hand, regularisation introduces a parameter which controls the error in addition to the grid spacing, and makes it difficult to locate the yield surfaces. Furthermore, the equations become stiffer and more difficult to solve, while the discontinuity at the yield surfaces causes large truncation errors. The present work attempts to investigate the strengths and weaknesses of such a method by applying it to the lid-driven cavity problem for a range of Bingham and Reynolds numbers (up to 100 and 5000 respectively). By employing techniques such as multigrid, local grid refinement, and an extrapolation procedure to reduce the effect of the regularisation parameter on the calculation of the yield surfaces (Liu et al. J. Non-Newtonian Fluid Mech. 102 (2002) 179-191), satisfactory results are obtained, although the weaknesses of the method become more noticeable as the Bingham number is increased.Syrakos, AlexandrosGeorgiou, Georgios CAlexandrou, Andreas NWed, 04 May 2016 06:07:14 GMT02 May 2016arXiv:1605.00590https://cds.cern.ch/record/2150582['arXiv:1605.00590']arXiv:1605.00590The interaction of $He^{-}$ with fullerenes
https://cds.cern.ch/record/2150574
The effects of interactions between He- and clusters of fullerenes in helium nanodroplets are described. Electron transfer from $He^{-}$ to $(C_{60})_n$ and $(C_{70})_n$ clusters results in the formation of the corresponding fullerene cluster dianions. This unusual double electron transfer appears to be concerted and is most likely guided by electron correlation between the two very weakly bound outer electrons in $He^{-}$. We suggest a mechanism which involves long range electron transfer followed by the conversion of $He^{+}$ into $He_{2}^{+}$, where formation of the $He-He$ bond in $He_{2}^{+}$ releases sufficient kinetic energy for the cation and the dianion to escape their Coulombic attraction. By analogy with the corresponding dications, the observation of a threshold size of n \geq 5 for formation of both $(C_{60})_n^{2-}$ and $(C_{70})_n^{2-}$ is attributed to Coulomb explosion rather than an energetic constraint. We also find that smaller dianions can be observed if water is added as a co-dopant. Other aspects of $He^{-}$ chemistry that are explored include its role in the formation of multiply charged fullerene cluster cations and the sensitivity of cluster dianion formation on the incident electron energy.Mauracher, ADaxner, MHuber, S EPostler, JRenzler, MDenifl, SScheier, PEllis, A MWed, 04 May 2016 06:07:13 GMT02 May 2016arXiv:1605.00537https://cds.cern.ch/record/2150574['arXiv:1605.00537']arXiv:1605.00537Localized travelling waves in the asymptotic suction boundary layer
https://cds.cern.ch/record/2150568
We present two spanwise-localized travelling wave solutions in the asymptotic suction boundary layer, obtained by continuation of solutions of plane Couette flow. One of the solutions has the vortical structures located close to the wall, similar to spanwise-localized edge states previously found for this system. The vortical structures of the second solution are located in the free stream far above the laminar boundary layer and are supported by a secondary shear gradient that is created by a large-scale low-speed streak. The dynamically relevant eigenmodes of this solution are concentrated in the free stream, and the departure into turbulence from this solution evolves in the free stream towards the walls. For invariant solutions in free-stream turbulence, this solution thus shows that that the source of energy of the vortical structures can be a dynamical structure of the solution itself, instead of the laminar boundary layer.Kreilos, TobiasGibson, John FSchneider, Tobias MWed, 04 May 2016 06:07:13 GMT02 May 2016arXiv:1605.00494https://cds.cern.ch/record/2150568['arXiv:1605.00494']arXiv:1605.00494Cavitation inception of a van der Waals fluid at a sack-wall obstacle
https://cds.cern.ch/record/2150554
Cavitation in a liquid moving past a constraint is numerically investigated by means of a free-energy lattice Boltzmann simulation based on the van der Waals equation of state. The fluid is streamed past an obstacle and, depending on the pressure drop between inlet and outlet, vapor formation underneath the corner of the sack-wall is observed. The circumstances of cavitation formation are investigated and it is found that the local bulk pressure and mean stress are insufficient to explain the phenomenon. Results obtained in this study strongly suggest that the viscous stress, interfacial contributions to the local pressure, and the Laplace pressure are relevant to the opening of a vapor cavity. This can be described by a generalization of Joseph's criterion that includes these contributions. A macroscopic investigation measuring mass flow rate behavior and discharge coefficient was also performed. As theoretically predicted, mass flow rate increases linearly with the square root of the pressure drop. However, when cavitation occurs, the mass flow growth rate is reduced and eventually it collapses into a choked flow state. In the cavitating regime, as theoretically predicted and experimentally verified, the discharge coefficient grows with the Nurick cavitation number.Kaehler, GBonelli, FGonnella, GLamura, AWed, 04 May 2016 06:07:12 GMT02 May 2016arXiv:1605.00399https://cds.cern.ch/record/2150554['arXiv:1605.00399']arXiv:1605.00399Dissociative Electron Attachment to the Nitroamine HMX (Octahydro-1,3,5,7-Tetranitro-1,3,5,7-Tetrazocine)
https://cds.cern.ch/record/2150550
In the present study, dissociative electron attachment (DEA) measurements with gas phase HMX, octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine, $C_4H_8N_8O_8$, have been performed by means of a crossed electron-molecular beam experiment. The most intense signals are observed at 46 and 176u and assigned to $NO_{2}^{-}$ and $C_3H_6N_5O_{4}^{-}$, respectively. Anion efficiency curves for 15 negatively charged fragments have been measured in the electron energy region from about 0-20 eV with an energy resolution of ~0.7 eV. Product anions are observed mainly in the low energy region, near 0 eV, arising from surprisingly complex reactions associated with multiple bond cleavages and structural and electronic rearrangement. The remarkable instability of HMX towards electron attachment with virtually zero kinetic energy reflects the highly explosive nature of this compound. Substantially different intensity ratios of resonances for common fragment anions allow distinguishing the nitroamines HMX and royal demolition explosive molecule (RDX) in negative ion mass spectrometry based on free electron capture.Postler, JGoulart, M MMatias, CMauracher, Ada Silva, F FerreiraScheier, PLimão-Vieira, PDenifl, SWed, 04 May 2016 06:07:11 GMT02 May 2016arXiv:1605.00374https://cds.cern.ch/record/2150550['arXiv:1605.00374']arXiv:1605.00374Supersymmetric correspondence in spectra on a graph and its line graph: From circuit theory to spoof plasmons on metallic lattices
https://cds.cern.ch/record/2150547
We investigate the supersymmetry (SUSY) structures for inductor-capacitor circuit networks on a simple regular graph and its line graph. We show that their eigenspectra must coincide (except, possibly, for the highest eigenfrequency) due to SUSY, which is derived from the topological nature of the circuits. To observe this spectra correspondence in the high-frequency range, we study spoof plasmons on metallic hexagonal and kagom\'e lattices. The band correspondence between them is predicted by a simulation. Using terahertz time-domain spectroscopy, we demonstrate the band correspondence of fabricated metallic hexagonal and kagom\'e lattices.Nakata, YosukeUrade, YoshiroNakanishi, ToshihiroMiyamaru, FumiakiTakeda, Mitsuo WadaKitano, MasaoWed, 04 May 2016 06:07:11 GMT02 May 2016arXiv:1605.00345https://cds.cern.ch/record/2150547['arXiv:1605.00345']arXiv:1605.00345Quench-Induced Degradation of the Quality Factor in Superconducting Resonators
https://cds.cern.ch/record/2150541
Quench of superconducting radio-frequency cavities frequently leads to the lowered quality factor Q0, which had been attributed to the additional trapped magnetic flux. Here we demonstrate that the origin of this magnetic flux is purely extrinsic to the cavity by showing no extra dissipation (unchanged Q0) after quenching in zero magnetic field, which allows us to rule out intrinsic mechanisms of flux trapping such as generation of thermal currents or trapping of the rf field. We also show the clear relation of dissipation introduced by quenching to the orientation of the applied magnetic field and the possibility to fully recover the quality factor by requenching in the compensated field. We discover that for larger values of the ambient field, the Q-factor degradation may become irreversible by this technique, likely due to the outward flux migration beyond the normal zone opening during quench. Our findings are of special practical importance for accelerators based on low- and medium-beta accelerating structures residing close to focusing magnets, as well as for all high-Q cavity-based accelerators.Checchin, MMartinello, MRomanenko, AGrassellino, ASergatskov, D APosen, SMelnychuk, OZasadzinski, J FWed, 04 May 2016 06:07:11 GMT01 May 2016arXiv:1605.00272https://cds.cern.ch/record/2150541['arXiv:1605.00272']arXiv:1605.00272Effects of Substituents in Polyvinylcarbazole Structures on Their Optical Properties
https://cds.cern.ch/record/2150527
Absorption, photoluminescence, and photoluminescence excitation spectra of solutions and thin films of N-vinylcarbazole polymers and copolymers with various substituents directly on the carbazole moiety and on the polymer chain were studied comprehensively. Polymers that were used previously to develop polymer composites with polymethine dyes having photosensitivity over a broad spectral range including the visible and near-IR regions were selected for the studies.Vertsimakha, YaLutsyk, PSyromyatnikov, VSavchenko, IWed, 04 May 2016 06:07:10 GMT30 Apr 2016arXiv:1605.00144https://cds.cern.ch/record/2150527['arXiv:1605.00144']arXiv:1605.00144Impact of guided reflection with peers on the development of effective problem solving strategies and physics learning
https://cds.cern.ch/record/2150522
Students must learn effective problem solving strategies in order to develop expertise in physics. Effective problem solving strategies include a conceptual analysis of the problem followed by planning of the solution, and then implementation, evaluation and reflection upon the process. Research suggests that converting a problem from the initial verbal representation to other suitable representation, e.g., diagrammatic representation, during the initial conceptual analysis can facilitate further analysis of the problem.6 But without guidance, many introductory physics students solve problems using superficial clues and cues and do not perceive problem solving as an opportunity for learning. Here, we describe a study which suggests that engaging students in reflection with peers about effective problem solving strategies while effective approaches are modeled for them and prompt feedback is provided may enhance desirable skills.Mason, Andrew JSingh, ChandralekhaWed, 04 May 2016 06:07:09 GMT29 Apr 2016arXiv:1605.00025https://cds.cern.ch/record/2150522['arXiv:1605.00025']arXiv:1605.00025Honolulu Rail Transit: International Lessons in Linking Form, Design, and Transportation
https://cds.cern.ch/record/2150520
The city of Honolulu, Hawaii is currently planning and developing a new rail transit system. While Honolulu has supportive density and topography for rail transit, questions remain about its ability to effectively integrate urban design and accessibility across the system. Every transit trip begins and ends with a walking trip from origins and to destinations: transportation planning must account for pedestrian safety, comfort, and access. Ildefons Cerda's 19th century utopian plan for Barcelona's Eixample district produced a renowned, livable urban form. The Eixample, with its well-integrated rail transit, serves as a model of urban design, land use, transportation planning, and pedestrian-scaled streets working in synergy to produce accessibility. This study discusses the urban form of Honolulu and the history and planning of its new rail transit system. Then it reviews the history of Cerda's plan for the Eixample and discusses its urban form and performance today. Finally it draws several lessons from Barcelona's urban design, accessibility, and rail transit planning and critically discusses their applicability to policy and design in Honolulu. This discussion is situated within wider debates around livable cities and social justice as it contributes several form and design lessons to the livability and accessibility literature while identifying potential concerns with privatization and displacement.Boeing, GeoffWed, 04 May 2016 06:07:09 GMT29 Apr 2016arXiv:1605.00002https://cds.cern.ch/record/2150520['arXiv:1605.00002']arXiv:1605.00002Beyond mean-field boson-fermion model for odd-mass nuclei
https://cds.cern.ch/record/2150516
A novel method for calculating spectroscopic properties of medium-mass and heavy atomic nuclei with an odd number of nucleons is introduced, based on the framework of nuclear energy density functional theory and the particle-core coupling scheme. The deformation energy surface of the even-even core, as well as the spherical single-particle energies and occupation probabilities of the odd particle(s), are obtained in a self-consistent mean-field calculation determined by the choice of the energy density functional and pairing interaction. This method uniquely determines the parameters of the Hamiltonian of the boson core, and only the strength of the particle-core coupling is specifically adjusted to selected data for a particular nucleus. The approach is illustrated in a systematic study of low-energy excitation spectra and transition rates of axially deformed odd-mass Eu isotopes.Nomura, KNikšić, TVretenar, DWed, 04 May 2016 06:06:58 GMT03 May 2016arXiv:1605.00755https://cds.cern.ch/record/2150516['arXiv:1605.00755']arXiv:1605.00755Development of the MICROMEGAS Detector for Measuring the Energy Spectrum of Alpha Particles by using a 241-Am Source
https://cds.cern.ch/record/2150508
We have developed MICROMEGAS (MICRO MEsh GASeous) detectors for detecting {\alpha} particles emitted from an 241-Am standard source. The voltage applied to the ionization region of the detector is optimized for stable operation at room temperature and atmospheric pressure. The energy of {\alpha} particles from the 241-Am source can be varied by changing the flight path of the {\alpha} particle from the 241 Am source. The channel numbers of the experimentally-measured pulse peak positions for different energies of the {\alpha} particles are associated with the energies deposited by the alpha particles in the ionization region of the detector as calculated by using GEANT4 simulations; thus, the energy calibration of the MICROMEGAS detector for {\alpha} particles is done. For the energy calibration, the thickness of the ionization region is adjusted so that {\alpha} particles may completely stop in the ionization region and their kinetic energies are fully deposited in the region. The efficiency of our MICROMEGAS detector for {\alpha} particles under the present conditions is found to be ~ 97.3 %.Kim, Do YoonHam, CheolminShin, Jae WonPark, Tae-SunHong, Seung-WooAndriamonje, SamuelKadi, YacineTenreiro, ClaudioWed, 04 May 2016 06:06:47 GMT03 May 2016arXiv:1605.00791https://cds.cern.ch/record/2150508['arXiv:1605.00791']arXiv:1605.00791An improved method for estimating the neutron background in measurements of neutron capture reactions
https://cds.cern.ch/record/2150503
The relation between the neutron background in neutron capture measurements and the neutron sensitivity related to the experimental setup is examined. It is pointed out that a proper estimate of the neutron background may only be obtained by means of dedicated simulations taking into account the full framework of the neutron-induced reactions and their complete temporal evolution. No other presently available method seems to provide reliable results, in particular under the capture resonances. An improved neutron background estimation technique is proposed, the main improvement regarding the treatment of the neutron sensitivity, taking into account the temporal evolution of the neutron-induced reactions. The technique is complemented by an advanced data analysis procedure based on relativistic kinematics of neutron scattering. The analysis procedure allows for the calculation of the neutron background in capture measurements, without requiring the time-consuming simulations to be adapted to each particular sample. A suggestion is made on how to improve the neutron background estimates if neutron background simulations are not available.Žugec, PBosnar, DColonna, NGunsing, FWed, 04 May 2016 06:06:47 GMT01 May 2016arXiv:1605.00225https://cds.cern.ch/record/2150503['arXiv:1605.00225']arXiv:1605.00225Supersymmetry Breaking as a new source for the Generalized Uncertainty Principle
https://cds.cern.ch/record/2150500
In this letter, we will demonstrate that the breaking of supersymmetry by a non-anticommutative deformation can be used to generate the generalized uncertainty principle. We will analyse the physical reasons for this observation, in the framework of string theory. We also discuss the relation between the generalized uncertainty principle and the Lee-Wick field theories.Faizal, MWed, 04 May 2016 06:06:21 GMT13 Apr 2016arXiv:1605.00925https://cds.cern.ch/record/2150500['arXiv:1605.00925']arXiv:1605.00925Effect of Thermal Fluctuations on a Charged Dilatonic Black Saturn
https://cds.cern.ch/record/2150384
In this paper, we will analyze the effect of thermal fluctuations on the thermodynamics of a charged dilatonic black Saturn. These thermal fluctuations will correct the thermodynamics of the charged dilatonic black Saturn. We will analyze the corrections to the thermodynamics of this system by first relating the fluctuations in the entropy to the fluctuations in the energy. Then, we will use the relation between entropy and a conformal field theory to analyze the fluctuations in the entropy. We will demonstrate that similar physical results are obtained from both these approaches. We will also study the effect of thermal fluctuations on the phase transition in this charged dilatonic black Saturn.Pourhassan, BehnamFaizal, MirWed, 04 May 2016 06:03:58 GMT01 May 2016arXiv:1605.00924https://cds.cern.ch/record/2150384['arXiv:1605.00924']arXiv:1605.00924New exact solutions of Bianchi I, Bianchi III and Kantowski-Sachs spacetimes in scalar-coupled gravity theories via Noether gauge symmetries
https://cds.cern.ch/record/2150382
The Noether symmetry approach is useful tool to restrict the arbitrariness in a gravity theory when the equations of motion are underdetermined due to the high number of functions to be determined in the ansatz. We consider two scalar-coupled theories of gravity, one motivated by induced gravity, the other more standard; in Bianchi I, Bianchi III and Kantowski-Sachs cosmological models. For these models, we present a full set of Noether gauge symmetries, which are more general than those obtained by the strict Noether symmetry approach in our recent work. Some exact solutions are derived using the first integrals corresponding to the obtained Noether gauge symmetries.Camci, UYildirim, AOz, I BasaranWed, 04 May 2016 06:03:58 GMT03 May 2016arXiv:1605.00864https://cds.cern.ch/record/2150382['arXiv:1605.00864']arXiv:1605.00864Noether gauge symmetry classes for pp-wave spacetimes
https://cds.cern.ch/record/2150381
The Noether gauge symmetries of geodesic Lagrangian for the pp-wave spacetimes are determined in each of the Noether gauge symmetry classes of the pp-wave spacetimes. It is shown that a type N pp-wave spacetime can admit at most three Noether gauge symmetry, and furthermore the number of Noether gauge symmetries turn out to be four, five, six, seven and eight. We found that all conformally flat plane wave spacetimes admit the maximal, i.e. ten, Noether gauge symmetry. Also it is found that if the pp-wave spacetime is non-conformally flat plane wave, then the number of Noether gauge symmetry is nine or ten. By means of the obtained Noether constants the search of the exact solutions of the geodesic equations for the pp-wave spacetimes is considered and we found new exact solutions of the geodesic equations in some special Noether gauge symmetry classes.Camci, UYildirim, AWed, 04 May 2016 06:03:58 GMT03 May 2016arXiv:1605.00862https://cds.cern.ch/record/2150381['arXiv:1605.00862']arXiv:1605.00862Plutos interaction with its space environment: Solar Wind, Energetic Particles & Dust
https://cds.cern.ch/record/2150338
The New Horizons spacecraft carried three instruments that measured the space environment near Pluto as it flew by on 14 July 2015. The Solar Wind Around Pluto instrument revealed an interaction region confined sunward of Pluto to within about 6 Pluto radii. The surprisingly small size is consistent with a reduced atmospheric escape rate as well as a particularly high solar wind flux. The Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI) observations suggested ions are accelerated and-or deflected around Pluto. In the wake of the interaction region PEPSSI observed suprathermal particle fluxes about one tenth the flux in the interplanetary medium, increasing with distance downstream. The Student Dust Counter, which measures radius greater than 1.4 um grains, detected 1 candidate impact from 5days before to 5 days after closest approach, indicating an upper limit for the dust density in the Pluto system of 4.6 per cubic km.Bagenal, FHorányi, MMcComas, D JMcNutt,, R LElliott, H AHill, M EBrown, L EDelamere, P AKollmann, PKrimigis, S MKusterer, MLisse, C MMitchell, D GPiquette, MPoppe, A RStrobel, D FSzalay, J RValek, PVandegriff, JWeidner, SZirnstein, E JStern, S AEnnico, KOlkin, C BWeaver, H AYoung, L AWed, 04 May 2016 06:02:47 GMT02 May 2016arXiv:1605.00749https://cds.cern.ch/record/2150338['arXiv:1605.00749']arXiv:1605.00749