Results for "A. Avison"

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The ALMA Observation Support ToolJun 17 2011The ALMA Observation Support Tool (OST) is an ALMA simulator which is interacted with solely via a standard web browser. It is aimed at users who may or may not be experts in interferometry, or those that do not wish to familarise themselves with the ... More
Tightening the belt: Constraining the mass and evolution in SDC335Jan 19 2015Recent ALMA observations identified one of the most massive star-forming cores yet observed in the Milky Way; SDC335-MM1, within the infrared dark cloud SDC335.579-0.292. Along with an accompanying core MM2, SDC335 appears to be in the early stages of ... More
Multi-Epoch Radio Imaging of gamma-ray Nova V959 MonOct 23 2017V959 Mon (Nova Mon 2012) was first detected by the Fermi Large Area Telescope in June 2012, as a transient gamma-ray source. Subsequent optical observations showed that this gamma-ray emission was due to a classical nova explosion. Multi-frequency observations ... More
Gravity drives the evolution of infrared dark hubs: JVLA observations of SDC13Jan 22 2018Converging networks of interstellar filaments i.e. hubs, have been recently linked to the formation of stellar clusters and massive stars. The goal is to study the kinematic and density structure of the SDC13 hub at high angular resolution to determine ... More
The curious case of II Lup: a complex morphology revealed with SAM/NACO and ALMAAug 01 2018We present the first-ever images of the circumstellar environment of the carbon-rich AGB star II Lup in the infrared and sub-mm wavelengths, and the discovery of the envelope's non-spherical morphology with the use of high-angular resolution imaging techniques ... More
A graphical tool for demonstrating the techniques of radio interferometryNov 01 2012We present a graphical interface designed to demonstrate the techniques of radio interferometry used by telescopes like ALMA, e-Merlin, the JVLA and SKA, in a manner accessible to the general public. Interferometry is an observational tech- nique used ... More
Unveiling the Early-Stage Anatomy of a Protocluster Hub with ALMAJul 29 2016Aug 12 2016High-mass stars shape the interstellar medium in galaxies, and yet, largely because the initial conditions are poorly constrained, we do not know how they form. One possibility is that high-mass stars and star clusters form at the junction of filamentary ... More
The 6-GHz multibeam maser survey III: comparison between the MMB and HOPSNov 21 2017We have compared the occurrence of 6.7-GHz and 12.2-GHz methanol masers with 22-GHz water masers and 6035-MHz excited-state OH masers in the 100 square degree region of the southern Galactic plane common to the Methanol Multibeam (MMB) and H2O southern ... More
Global collapse of molecular clouds as a formation mechanism for the most massive starsJul 09 2013The relative importance of primordial molecular cloud fragmentation versus large-scale accretion still remains to be assessed in the context of massive core/star formation. Studying the kinematics of the dense gas surrounding massive-star progenitors ... More
Unveiling the Early-Stage Anatomy of a Protocluster Hub with ALMAJul 29 2016Sep 29 2016High-mass stars shape the interstellar medium in galaxies, and yet, largely because the initial conditions are poorly constrained, we do not know how they form. One possibility is that high-mass stars and star clusters form at the junction of filamentary ... More
Major structures of the inner Galaxy delineated by 6.7-GHz methanol masersMar 21 2011We explore the longitude-velocity distribution of 6.7-GHz methanol masers in the context of the inner structure of our Galaxy. We analyse the correlation in velocities within this distribution and identify density enhancements indicating large-scale regions ... More
The mid-infrared environments of 6.7 GHz Methanol Masers from the Methanol Multi-Beam SurveyDec 08 2012We present a study of the mid-infrared environments and association with star formation tracers of 6.7 GHz methanol masers taken from the Methanol Multi-Beam (MMB) Survey. Our ultimate goal is to establish the mass of the host star and its evolutionary ... More
The 6-GHz methanol multibeam maser catalogue IV: Galactic longitudes 186 to 330 including the Orion-Monoceros regionJan 03 2012We present the fourth portion of a Galactic Plane survey of methanol masers at 6668 MHz, spanning the longitude range 186 degrees to 330 degrees. We report 207 maser detections, 89 new to the survey. This completes the southern sky part of the Methanol ... More
The 6-GHz methanol multibeam maser catalogue II: Galactic longitudes 6 to 20Jul 19 2010We present the second portion of an unbiased survey of the Galactic plane for 6668-MHz methanol masers. This section of the survey spans the longitude range 6 degrees to 20 degrees. We report the detection of 119 maser sources, of which 42 are new discoveries. ... More
Excited-state hydroxyl maser catalogue from the methanol multibeam survey -- I. Positions and VariabilityMay 09 2016May 18 2016We present the results of the first complete unbaised survey of the Galactic Plane for 6035-MHz excited-state hydroxyl masers undertaken as part of the Methanol Multibeam Survey. These observations cover the Galactic longitude ranges $186^{\circ}< l < ... More
The Science Case for ALMA Band 2 and Band 2+3Feb 07 2016Aug 14 2017We discuss the science drivers for ALMA Band 2 which spans the frequency range from 67 to 90 GHz. The key science in this frequency range are the study of the deuterated molecules in cold, dense, quiescent gas and the study of redshifted emission from ... More
Young massive star cluster formation in the Galactic Centre is driven by global gravitational collapse of high-mass molecular cloudsMar 14 2019Young massive clusters (YMCs) are the most compact, high-mass stellar systems still forming at the present day. The precursor clouds to such systems are, however, rare due to their large initial gas mass reservoirs and rapid dispersal timescales due to ... More
ALMA reveals sunburn: CO dissociation around AGB stars in the globular cluster 47 TucanaeAug 21 2015ALMA observations show a non-detection of carbon monoxide around the four most luminous asymptotic giant branch (AGB) stars in the globular cluster 47 Tucanae. Stellar evolution models and star counts show that the mass-loss rates from these stars should ... More
The Science Case for ALMA Band 2 and Band 2+3Feb 07 2016We discuss the science drivers for ALMA Band 2 which spans the frequency range from 67 to 90 GHz. The key science in this frequency range are the study of the deuterated molecules in cold, dense, quiescent gas and the study of redshifted emission from ... More
12.2-GHz methanol maser MMB follow-up catalogue - II. Longitude range 186 to 330 degreesJul 23 2012We present the second portion of a catalogue of 12.2-GHz methanol masers detected towards 6.7-GHz methanol masers observed in the unbiased Methanol Multibeam (MMB) Survey. Using the Parkes radio telescope we have targeted all 207 6.7-GHz methanol masers ... More
The structure and early evolution of massive star forming regions - Substructure in the infrared dark cloud SDC13Jul 26 2016Investigations into the substructure of massive star forming regions are essential for understanding the observed relationships between core mass distributions and mass distributions in stellar clusters, differentiating between proposed mechanisms of ... More
The 6-GHz methanol multibeam maser catalogue I: Galactic Centre region, longitudes 345 to 6Feb 12 2010We have conducted a Galactic plane survey of methanol masers at 6668 MHz using a 7-beam receiver on the Parkes telescope. Here we present results from the first part, which provides sensitive unbiased coverage of a large region around the Galactic Centre. ... More
ALMA observations of Lyman-alpha Blob 1: halo sub-structure illuminated from withinAug 09 2016We present new Atacama Large Millimeter/Submillimeter Array (ALMA) 850um continuum observations of the original Lyman-alpha Blob (LAB) in the SSA22 field at z=3.1 (SSA22-LAB01). The ALMA map resolves the previously identified submillimeter source into ... More
The 6-GHz Multibeam Maser Survey I. TechniquesOct 29 2008A new 7-beam 6-7 GHz receiver has been built to survey the Galaxy and the Magellanic Clouds for newly forming high-mass stars that are pinpointed by strong methanol maser emission at 6668 MHz. The receiver was jointly constructed by Jodrell Bank Observatory ... More
12.2-GHz methanol maser MMB follow-up catalogue - I. Longitude range 330 to 10 degreesJan 06 2012We present a catalogue of 12.2-GHz methanol masers detected towards 6.7-GHz methanol masers observed in the unbiased Methanol Multibeam (MMB) survey in the longitude range 330\circ (through 360\circ) to 10\circ. This is the first portion of the catalogue ... More
Statistical properties of 12.2 GHz methanol masers associated with a complete sample of 6.7 GHz methanol masersApr 01 2011We present definitive detection statistics for 12.2 GHz methanol masers towards a complete sample of 6.7 GHz methanol masers detected in the Methanol Multibeam survey south of declination -20 degrees. In total, we detect 250 12.2 GHz methanol masers towards ... More
12.2-GHz methanol maser MMB follow-up catalogue - III. Longitude range 10 to 20 degreesDec 18 2013We present the third instalment of a series of catalogues presenting 12.2-GHz methanol maser observations made towards each of the 6.7-GHz methanol masers detected in the Methanol Multibeam (MMB) Survey. The current portion of the catalogue includes the ... More
ALMA reveals the aftermath of a white dwarf--brown dwarf merger in CK VulpeculaeSep 16 2018We present Atacama Large Millimeter-Submillimeter Array (ALMA) observations of CK Vulpeculae which is identified with "Nova Vulpeculae 1670". They trace obscuring dust in the inner regions of the associated nebulosity. The dust forms two cocoons, each ... More
An Overview of the 2014 ALMA Long Baseline CampaignApr 19 2015Apr 24 2015A major goal of the Atacama Large Millimeter/submillimeter Array (ALMA) is to make accurate images with resolutions of tens of milliarcseconds, which at submillimeter (submm) wavelengths requires baselines up to ~15 km. To develop and test this capability, ... More
Effects of the stellar wind on X-ray spectra of Cygnus X-3Oct 30 2007Feb 04 2008We study X-ray spectra of Cyg X-3 from BeppoSAX, taking into account absorption and emission in the strong stellar wind of its companion. We find the intrinsic X-ray spectra are well modelled by disc blackbody emission, its upscattering by hot electrons ... More
On open superstring partition function in inhomogeneous rolling tachyon backgroundOct 27 2003Jan 27 2004We consider open superstring partition function Z on the disc in time-dependent tachyon background T= f(x_i) e^{m x_0} where the profile function f depends on spatial coordinates. We compute Z to second order in derivatives of f and compare the result ... More
On gravitational couplings in D-brane actionNov 12 2002Oct 26 2004We compute the two closed string graviton - two open string scalar scattering amplitude on the disc to show that there is no second-derivative curvature - scalar coupling term R X^2 in the low-energy effective action of a D-brane in curved space in type ... More
Coherent effects in double-barrier Josephson junctionsDec 07 1999The general solution for ballistic electronic transport through double-barrier Josephson junctions is derived. We show the existence of a regime of phase-coherent transport in which the supercurrent is proportional to the single barrier transparency and ... More
The origin of the first and third generation fermion masses in a technicolor scenarioFeb 19 2003Jan 22 2004We argue that the masses of the first and third fermionic generations, which are respectively of the order of a few MeV up to a hundred GeV, are originated in a dynamical symmetry breaking mechanism leading to masses of the order $\alpha \mu$, where $\alpha$ ... More
On (non)integrability of classical strings in p-brane backgroundsNov 15 2012Jan 07 2013We investigate the question of possible integrability of classical string motion in curved p-brane backgrounds. For example, the D3-brane metric interpolates between the flat and the AdS_5 x S^5 regions in which string propagation is integrable. We find ... More
On the power of non-local boxesApr 18 2005Nov 07 2005A non-local box is a virtual device that has the following property: given that Alice inputs a bit at her end of the device and that Bob does likewise, it produces two bits, one at Alice's end and one at Bob's end, such that the XOR of the outputs is ... More
Casimir effect for scalar fields under Robin boundary conditions on platesJul 31 2000Oct 22 2001We study the Casimir effect for scalar fields with general curvature coupling subject to mixed boundary conditions $(1+\beta_{m}n^{\mu}\partial_{\mu})\phi =0$ at $x=a_{m}$ on one ($m=1$) and two ($m=1,2$) parallel plates at a distance $a\equiv a_{2}-a_{1}$ ... More
Technicolor models with coupled systems of Schwinger-Dyson equationsFeb 28 2019When Technicolor (TC), QCD, Extended Technicolor (ETC) and other interactions become coupled through their different Schwinger-Dyson equations, the solution of these equations are modified in comparison with the ones of the isolated equations. The change ... More
A statistical model of three-dimensional anisotropy and intermittency in strong Alfvénic turbulenceMay 24 2016Dec 14 2016We propose a simple statistical model of three-dimensionally anisotropic, intermittent, strong Alfv\'enic turbulence, incorporating both critical balance and dynamic alignment. Our model is based on log-Poisson statistics for Elsasser-field increments ... More
Exact string background from a WZW model based on the Heisenberg groupMar 07 1994A WZW model for the non-semi-simple D-dimensional Heisenberg group, which directly generalizes the E_{2}^{c} group, is constructed. It is found to correspond to an D-dimensional string background of plane-wave type with physical Lorentz signature D-2. ... More
Notes on non-thermal X-ray radiation of radio supernova remnant W50 and collimated radiation of SS433Jun 19 2013Diffuse X-ray emission of the radio nebula W50 along the line of the of jets of the microquasar SS433 has a non-thermal power law component. This could be the inverse-Compton scattered emission of the SS433 accretion disk funnel, which is collimated in ... More
Next-to-next-to-leading order vacuum polarization function of heavy quark near threshold and sum rules for $b \bar b$ systemMar 16 1998Apr 06 1998A correlator of the vector current of a heavy quark is computed analytically near threshold in the next-to-next-to-leading order in perturbative and relativistic expansion that includes $\al_s^2$, $\al_sv$ and $v^2$ corrections in the coupling constant ... More
Comment on ``Next-to-next-to-leading order vacuum polarization function of heavy quark near threshold and sum rules for $b \bar b$ system'' and ``Next-to-next-to-leading order relation between $R(e^+e^-\to b\bar b)$ and $Γ_{\rm sl}(b\to clν_l)$ and precise ... MoreJan 19 1999The most recent recalculation of the two-loop correction to the static quark-antiquark potential gave the numerical value different from the previously known one. We comment on the effect this change produces on the numerical estimates of the bottom quark ... More
Extended analysis of the "penguin" part of $K\toππ$ amplitudeMar 14 1995We make an attempt to clarify the role of the annihilation or "penguin" mode in the description of the $K\rightarrow\pi\pi$ decay within the Standard Model. The attention is concentrated on new operators in the effective $\Delta S=1$ Hamiltonian and the ... More
Curved space resolution of singularity of fractional D3-branes on conifoldNov 01 2001We construct a supergravity dual to the cascading $SU(N+M) x SU(N)$ supersymmetric gauge theory (related to fractional D3-branes on conifold according to Klebanov et al) in the case when the 3-space is compactified on $S^3$ and in the phase with unbroken ... More
Schwinger-Dyson approach and its application to generate a light composite scalarJan 15 2016Feb 24 2016We discuss the possibility of generating a light composite scalar boson, in a scenario that we may generically call Technicolor, or in any variation of a strongly interacting theory, where by light we mean a scalar composite mass about one order of magnitude ... More
Dynamical gluon mass corrections in heavy quarkonia decaysApr 26 2000Using the expression of the dynamical gluon mass obtained through the operator product expansion we discuss the relevance of gluon mass effects in the decays V -> hadrons (V = J/Psi, Upsilon). Relativistic and radiative corrections are also introduced ... More
Semiclassical rigid strings with two spins in AdS_5Nov 12 2009Semiclassical spinning string states in AdS_5 are, in general, characterised by the three SO(2,4) conserved charges: the energy E and the two spins S_1 and S_2. We discuss several examples of explicit classical solutions for rigid closed strings of (bended) ... More
Search for excited electrons through $γγ$ scatteringAug 10 2012We study the potential of $\gamma \gamma$ option of future high energy linear $e^{+}e^{-}$ colliders to search for excited electrons with spin-1/2. We calculate single production cross sections, give the angular distributions and $f-m^*$ contour plots ... More
A study of spectra of Cyg X-3 observed by BeppoSAXDec 22 2004Jan 10 2005We model the ~1-200 keV spectra of Cygnus X-3 observed by BeppoSAX. The continuum, modeled by Comptonization in a hybrid plasma, is modified by the strongly ionized plasma of the stellar wind of the Wolf-Rayet companion star. Discrete absorption and emission ... More
Quantum Corrections to Bekenstein-Hawking Black Hole Entropy and Gravity Partition FunctionsApr 25 2013Algebraic aspects of the computation of partition functions for quantum gravity and black holes in $AdS_3$ are discussed. We compute the sub-leading quantum corrections to the Bekenstein-Hawking entropy. It is shown that the quantum corrections to the ... More
Chiral expansion of nucleon PDF at $x\sim m_π/M_N$Nov 14 2013Based on the chiral perturbation theory, we investigate the low-energy dynamics of nucleon parton distributions. We show that in different regions of the momentum fraction $x$ the chiral expansion is significantly different. For nucleon parton distributions ... More
Can Electro-Weak $\h$-Term be Observable ?May 14 1993We rederive and discuss the result of the previous paper that in the standard model $\theta$-term related to $W$-boson field can not be induced by weak instantons. This follows from the existence of the fermion zero mode in the instanton field even when ... More
Optimized perturbation theory for bound states: toy model and realistic problemJun 20 1995Within quantum mechanics model we study the problem of resummation of an asymptotic perturbation series for bound state parameters via optimization of the perturbative expansion. A possible application of the method to the positronium lifetime calculation ... More
The 2MASS Color-Magnitude Diagram of the Center of the Sagittarius Dwarf Galaxy: Photometric Measurements of a Surprisingly High Mean MetallicityAug 03 2001We present the Two Micron All Sky Survey (2MASS) (J-K, K) color-magnitude diagram for the region within 1 degree of the center of the Sagittarius dwarf spheroidal galaxy. Using the slope of the red giant branch (RGB), we determine a mean metallicity for ... More
Phi-Homological Properties of Beurling AlgebrasJan 11 2014In this paper, we investigate $\phi$-homological properties for Beurling algebras, where $\phi$ is a character on those Banach algebras. We show that $L^{1}(G,w)$ is $\phi_{0}$-biprojective if and only if $G$ is compact, where $\phi_{0}$ is the augmentation ... More
Efficiency limits of diffusive shock accelerationAug 10 2007It is well accepted today that diffusive acceleration in shocks results to the cosmic ray spectrum formation. This is in principle true for non-relativistic shocks, since there is a detailed theory covering a large range of their properties and the resulting ... More
Electromagnetic theory of sound and phonons in liquidMar 02 2016Apr 05 2016Sound waves in and dielectric liquid, that consists of subsystems of valency electrons with effective mass and ions which interact through the long-wave potential electric field are considered, on analogies with and metallic liquid, but with the requirement, ... More
Seiberg-Witten Systems and Whitham Hierarchies: a Short ReviewSep 28 1998Oct 05 1998We briefly review the Whitham hierarchies and their applications to integrable systems of the Seiberg-Witten type. The simplest example of the N=2 supersymmetric SU(2) pure gauge theory is considered in detail and the corresponding Whitham solutions are ... More
Solutions to the reflection equation and integrable systems for N=2 SQCD with classical groupsFeb 03 1999Integrable systems underlying the Seiberg-Witten solutions for the N=2 SQCD with gauge groups SO(n) and Sp(n) are proposed. They are described by the inhomogeneous XXX spin chain with specific boundary conditions given by reflection matrices. We attribute ... More
Gauge string in the fermion asymmetric matterAug 24 1999Two new effects of interaction of the gauge string with a homogeneous density of fermions are considered in a gauge model with an anomalous coupling of vector fields with fermions. First, the presence of an induced nonzero magnetic-like helicity on the ... More
Fermi LAT Observation of Diffuse Gamma-Rays Produced Through Interactions between Local Interstellar Matter and High Energy Cosmic RaysAug 08 2009Aug 26 2009Observations by the Large Area Telescope (LAT) on the \textit{Fermi} mission of diffuse $\gamma$-rays in a mid-latitude region in the third quadrant (Galactic longitude $l$ from $200\arcdeg$ to $260\arcdeg$ and latitude $| b |$ from $22\arcdeg$ to $60\arcdeg$) ... More
Fermi Large Area Telescope Bright Gamma-ray Source ListFeb 08 2009May 19 2009Following its launch in June 2008, the Fermi Gamma-ray Space Telescope (Fermi) began a sky survey in August. The Large Area Telescope (LAT) on Fermi in 3 months produced a deeper and better-resolved map of the gamma-ray sky than any previous space mission. ... More
Fermi-LAT Observations of Two Gamma-Ray Emission Components from the Quiescent SunApr 11 2011We report the detection of high-energy gamma rays from the quiescent Sun with the Large Area Telescope (LAT) on board the Fermi Gamma-Ray Space Telescope (Fermi) during the first 18 months of the mission. These observations correspond to the recent period ... More
Observation of Supernova Remnant IC443 with the Fermi Large Area TelescopeFeb 10 2010We report observation of the supernova remnant IC443 (G189.1+3.0) with the Fermi Gamma-ray Space Telescope Large Area Telescope (LAT) in the energy band between 200MeV and 50GeV. IC443 is a shell-type supernova remnant with mixed morphology located off ... More
The Vela Pulsar: Results from the First Year of Fermi LAT ObservationsFeb 22 2010We report on analysis of timing and spectroscopy of the Vela pulsar using eleven months of observations with the Large Area Telescope on the Fermi Gamma-Ray Space Telescope. The intrinsic brightness of Vela at GeV energies combined with the angular resolution ... More
Measuring Vacuum Polarization with Josephson JunctionsMar 06 2010We argue that the vacuum polarization by the virtual electron-positron pairs can be measured by studying a Josephson junction in a strong magnetic field. The vacuum polarization results in a weak dependence of the Josephson constant on the magnetic field ... More
The mass of $η_b$May 26 2009In this paper we briefly review the advances and problems in the QCD theory of the $\eta_b$ mass.
The Discovery of Cherenkov Radiation and its use in the detection of extensive air showersJan 24 2011Cascades of charged particles are created when high-energy cosmic rays enter the earth's atmosphere: these 'extensive air-showers' are studied to gain information on the energy spectrum, arrival direction distribution and mass composition of the particles ... More
Highlights from the Pierre Auger Obseervatory - the birth of the hybrid eraJan 15 2008Highlights from the Pierre Auger Observatory are presented. In particular there is a detailed discussion of of the cosmic ray energy spectrum from 0.3 EeV to 100 EeV and of the mass composition above 1 EeV.
The mass composition of cosmic rays above 10^17 eVAug 05 2004It is shown that our knowledge of the mass composition of cosmic rays is deficient at all energies above 10^17 eV. Systematic differences between different measurements are discussed and, in particular, it is argued that there is no compelling evidence ... More
Ultra High Energy Cosmic Rays: the present position and the need for mass composition measurementsDec 18 2003The present situation with regard to experimental data on ultra high-energy cosmic rays is briefly reviewed. Whilst detailed knowledge of the shape of the energy spectrum is still lacking, it is clear that events above 10^20 eV do exist. Evidence for ... More
Shadowing of Ultrahigh Energy NeutrinosMar 22 1996The rise with energy of the neutrino--nucleon cross section implies that at energies above few TeV the Earth is becoming opaque to cosmic neutrinos. The neutrinos interact with the nucleons through the weak charged current, resulting into absorption, ... More
Metal-insulator transitions and the effects of electron-electron interactions in two-dimensional electron systemsMay 24 2004Mar 07 2005Experimental results on the metal-insulator transitions and the anomalous properties of strongly interacting two-dimensional electron systems are reviewed and critically analyzed. Special attention is given to recent results for the strongly enhanced ... More
Radiative Transfer Effects on the Lya ForestOct 09 2005Strong observational evidence for a fluctuating ultraviolet background (UVB) has been accumulating through a number of studies of the HI and HeII Lya forest as well as accurate IGM metallicity measurements. UVB fluctuations could arise both from the inhomogeneous ... More
Tsallis statistics as a tool for studying interstellar turbulenceMay 15 2009Dec 09 2009We used magnetohydrodynamic (MHD) simulations of interstellar turbulence to study the probability distribution functions (PDFs) of increments of density, velocity, and magnetic field. We found that the PDFs are well described by a Tsallis distribution, ... More
Strong Imbalanced TurbulenceSep 05 2007Jul 07 2008We consider stationary, forced, imbalanced, or cross-helical MHD Alfvenic turbulence where the waves traveling in one direction have higher amplitudes than the opposite waves. This paper is dedicated to so-called strong turbulence, which cannot be treated ... More
BRST-Invariant Deformations of Geometric Structures in Sigma ModelsOct 06 2011We study a Lie algebra of formal vector fields $W_n$ with its application to the perturbative deformed holomorphic symplectic structure in the A-model, and a Calabi-Yau manifold with boundaries in the B-model. We show that equivalent classes of deformations ... More
Dynamics of a nano-scale rotor driven by single-electron tunnelingApr 26 2012We investigate theoretically the dynamics and the charge transport properties of a rod-shaped nano-scale rotor, which is driven by a similar mechanism as the nanomechanical single-electron transistor (NEMSET). We show that a static electric potential ... More
Eigenvalue conjecture and colored Alexander polynomialsOct 10 2016We connect two important conjectures in the theory of knot polynomials. The first one is the property Al_R(q) = Al_{[1]}(q^{|R|}) for all single hook Young diagrams R, which is known to hold for all knots. The second conjecture claims that all the mixing ... More
On AGT relation in the case of U(3)Aug 18 2009Sep 09 2009We consider the AGT relation, expressing conformal blocks for the Virasoro and W-algebras in terms of Nekrasov's special functions, in the simplest case of the 4-point functions for the first non-trivial W_3 algebra. The standard set of Nekrasov functions ... More
Is Strong Gravitational Radiation predicted by TeV-Gravity?Dec 06 2006In TeV-gravity models the gravitational coupling to particles with energies E\sim m_{Pl} \sim 10 TeV is not suppressed by powers of ultra-small ratio E/M_{Pl} with M_{Pl} \sim 10^{19} GeV. Therefore one could imagine strong synchrotron radiation of gravitons ... More
Is pentaquark doublet a hadronic molecule?Jul 16 2015A recently announced discovery by LHCb of a doublet of overlapping pentaquark resonances poses a question of what can be the origin of this doublet structure. We attract attention to the fact that such degeneracy could naturally arise if constituent "baryon" ... More
Virasoro constraints for Kontsevich-Hurwitz partition functionJul 17 2008Sep 14 2008M.Kazarian and S.Lando found a 1-parametric interpolation between Kontsevich and Hurwitz partition functions, which entirely lies within the space of KP tau-functions. V.Bouchard and M.Marino suggested that this interpolation satisfies some deformed Virasoro ... More
Radiation Beyond Four Space-Time DimensionsMar 09 2007We present a list of formulas describing classical radiation of the rank s tensor field from an accelerated point-like source in flat space-time of arbitrary even dimension d. This allows straightforward evaluating the total intensity and radiated momentum ... More
The ground state of the Pomeron and its decays to light mesons and photonsApr 06 2016Jul 04 2016The problem of the timelike Pomeron coupling to light mesons and photons is considered in light of available data on high-energy meson-proton scattering. Possible correspondence of $f_2(1950)$ resonance to the ground state of the Pomeron is argued.
A gradient catastrophe mechanism in contexts of the phase change conditionJan 09 2016The paper describes the mechanism of occurrence of a gradient catastrophe when changing phase. Materials shows that classical methods of estimation theory of functions do not fit the problem of studying the gradient catastrophe. We present material showing ... More
Quantum Law of Motion: Analysis and Extension to Higher DimensionsOct 05 2008In this paper, we review the recently formulated quantum laws of motion and provide new observations. We also extend these laws to higher dimensions. By applying in two dimensions the obtained relations to charge submitted to an electric central potential, ... More
Rational functions with real critical points and the B. and M. Shapiro conjecture in real enumerative geometryMay 11 2004Suppose that 2d-2 tangent lines to the rational normal curve z\mapsto (1 : z : ... : z^d) in d-dimensional complex projective space are given. It was known that the number of codimension 2 subspaces intersecting all these lines is always finite; for a ... More
Network growth with preferential attachment and without "rich get richer" mechanismJul 02 2015We propose a simple preferential attachment model of growing network using the complementary probability of Barab\'asi-Albert (BA) model, i.e., $\Pi(k_i) \propto 1-\frac{k_i}{\sum_j k_j}$. In this network, new nodes are preferentially attached to not ... More
Stellar magnetism, winds and their effects on planetary environmentsAug 12 2016Here, I review some recent works on magnetism of cool, main-sequence stars, their winds and potential impact on surrounding exoplanets. The winds of these stars are very tenuous and persist during their lifetime. Although carrying just a small fraction ... More
Dilute Fermi gas: kinetic and interaction energiesJan 13 2004A dilute homogeneous 3D Fermi gas in the ground state is considered for the case of a repulsive pairwise interaction. The low-density (dilution) expansions for the kinetic and interaction energies of the system in question are calculated up to the third ... More
Averaging in cosmological models using scalarsAug 28 2009The averaging problem in cosmology is of considerable importance for the correct interpretation of cosmological data. A rigorous mathematical definition of averaging in a cosmological model is necessary. In general, a spacetime is completely characterized ... More
Cosmological Observations: Averaging on the Null ConeMay 14 2009The universe is not isotropic or spatially homogeneous on local scales. The averaging of local inhomogeneities in general relativity can lead to significant dynamical effects on the evolution of the universe and on the interpretation of cosmological data. ... More
A Class of Exact Classical Solutions to String TheoryNov 07 2002We show that the recently obtained class of spacetimes for which all of the scalar curvature invariants vanish (which can be regarded as generalizations of pp-wave spacetimes) are exact solutions in string theory to all perturbative orders in the string ... More
The Dynamics of Brane-World Cosmological ModelsApr 09 2005Brane-world cosmology is motivated by recent developments in string/M-theory and offers a new perspective on the hierarchy problem. In the brane-world scenario, our Universe is a four-dimensional subspace or {\em brane} embedded in a higher-dimensional ... More
Interface resistance in ferromagnet/superconductor junctionsJul 13 1999Results of theoretical study of spin-polarized tunneling in ferromagnet/superconductor junctions are presented. Spin and charge currents are calculated as a function of applied voltage and spin polarization in a ferromagnet. The model takes into account ... More
Local potential approximation for the renormalization group flow of fermionic field theoriesJun 11 2013Sep 30 2013The second functional derivative of the effective potential of pure fermionic field theories is rewritten in a factorized form which facilitates the evaluation of the renormalisation flow rate of the effective action in the Wetterich equation. It is applied ... More
Squeezed gluon vacuum and the global colour model of QCDSep 13 1999We discuss how the vacuum model of Celenza and Shakin with a squeezed gluon condensate can explain the existence of an infrared singular gluon propagator frequently used in calculations within the global colour model. In particular, it reproduces a recently ... More
Short Distance QCD Contribution to the Electroweak Mass Difference of PionsMar 14 1997It is known that the short distance QCD contribution to the mass difference of pions is quadratic on the quark masses, and irrelevant with respect to the long distance part. It is also considered in the literature that its calculation contain infinities, ... More