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Solar coronal lines in the visible and infrared. A rough guideAug 11 2017Nov 22 2017We review the coronal visible and infrared lines, collecting previous observations, and comparing, whenever available, observed radiances with those predicted by various models: the quiet Sun, a moderately active Sun, and an active region as observed ... More

Simulations of the Kelvin-Helmholtz instability driven by coronal mass ejections in the turbulent coronaAug 12 2014Jan 13 2016Recent high resolution AIA/SDO images show evidence of the development of the Kelvin-Helmholtz instability, as coronal mass ejections (CMEs) expand in the ambient corona. A large-scale magnetic field mostly tangential to the interface is inferred, both ... More

Using the Dipolar and Quadrupolar Moments to Improve Solar-Cycle Predictions Based on the Polar Magnetic FieldsAug 09 2013Oct 06 2013The solar cycle and its associated magnetic activity are the main drivers behind changes in the interplanetary environment and Earth's upper atmosphere (commonly referred to as space weather and climate). In recent years there has been an effort to develop ... More

Detection of X-ray Resonance Scattering in Active Stellar CoronaeMay 26 2004An analysis of Lyman series lines arising from hydrogen-like oxygen and neon ions in the coronae of the active RS CVn-type binaries II Peg and IM Peg, observed using the {\it Chandra} High Resolution Transmission Grating Spectrograph, shows significant ... More

The Wave Properties of Coronal Bright Fronts Observed Using SDO/AIASep 27 2011Coronal bright fronts (CBFs) are large scale wavefronts that propagate though the solar corona at hundreds of kilometers per second. While their kinematics have been studied in detail, many questions remain regarding the temporal evolution of their amplitude ... More

Heating of the Solar Chromosphere and Corona by Alfven Wave TurbulenceMay 02 2011A three-dimensional MHD model for the propagation and dissipation of Alfven waves in a coronal loop is developed. The model includes the lower atmospheres at the two ends of the loop. The waves originate on small spatial scales (less than 100 km) inside ... More

Magnetohydrodynamic Modeling of the Solar Eruption on 2010 April 8Apr 25 2013Jul 08 2014The structure of the coronal magnetic field prior to eruptive processes and the conditions for the onset of eruption are important issues that can be addressed through studying the magnetohydrodynamic stability and evolution of nonlinear force-free field ... More

The Relation between Solar Eruption Topologies and Observed Flare Features I: Flare RibbonsJun 10 2015In this paper we present a topological magnetic field investigation of seven two-ribbon flares in sigmoidal active regions observed with Hinode, STEREO, and SDO. We first derive the 3D coronal magnetic field structure of all regions using marginally unstable ... More

Dynamics of the solar magnetic bright points derived from their horizontal motionsApr 19 2012The sub-arcsec bright points (BP) associated with the small scale magnetic fields in the lower solar atmosphere are advected by the evolution of the photospheric granules. We measure various quantities related to the horizontal motions of the BPs observed ... More

Nonlinear Force-Free Field Modeling of the Solar Magnetic Carpet and Comparison with SDO/HMI and Sunrise/IMaX ObservationsAug 03 2014In the quiet solar photosphere, the mixed polarity fields form a magnetic carpet, which continuously evolves due to dynamical interaction between the convective motions and magnetic field. This interplay is a viable source to heat the solar atmosphere. ... More

The Spatial and Temporal Dependence of Coronal Heating by Alfven Wave TurbulenceJun 25 2013The solar atmosphere may be heated by Alfven waves that propagate up from the convection zone and dissipate their energy in the chromosphere and corona. To further test this theory, we consider wave heating in an active region observed on 2012 March 7. ... More

Coronal Plasma Characterization via Coordinated Infrared and Extreme Ultraviolet Observations of a Total Solar EclipseJan 29 2019We present coordinated coronal observations of the August 21, 2017 total solar eclipse with the Airborne Infrared Spectrometer (AIR-Spec) and the Extreme-ultraviolet Imaging Spectrometer (EIS). These instruments provide an unprecedented view of the solar ... More

Coronal Plasma Characterization via Coordinated Infrared and Extreme Ultraviolet Observations of a Total Solar EclipseJan 29 2019Feb 14 2019We present coordinated coronal observations of the August 21, 2017 total solar eclipse with the Airborne Infrared Spectrometer (AIR-Spec) and the Extreme-ultraviolet Imaging Spectrometer (EIS). These instruments provide an unprecedented view of the solar ... More

Observations and modeling of the emerging EUV loops in the quiet Sun as seen with the Solar Dynamics ObservatoryMar 14 2013We used data from the Helioseismic and Magnetic Imager (HMI), and Atmospheric Imaging Assembly (AIA) on the \textit{Solar Dynamics Observatory} (SDO) to study coronal loops at small scales, emerging in the quiet Sun. With HMI line-of-sight magnetograms, ... More

Universality of rain event size distributionsOct 20 2010We compare rain event size distributions derived from measurements in climatically different regions, which we find to be well approximated by power laws of similar exponents over broad ranges. Differences can be seen in the large-scale cutoffs of the ... More

X-Ray Searches for Solar AxionsJan 22 2012Axions generated thermally in the solar core can convert nearly directly to X-rays as they pass through the solar atmosphere via interaction with the magnetic field. The result of this conversion process would be a diffuse centrally-concentrated source ... More

Observations of Subarcsecond Bright Dots in the Transition Region above Sunspots with the Interface Region Imaging SpectrographJul 03 2014Observations with the Interface Region Imaging Spectrograph (IRIS) have revealed numerous sub-arcsecond bright dots in the transition region above sunspots. These bright dots are seen in the 1400\AA{} and 1330\AA{} slit-jaw images. They are clearly present ... More

Solar Cycle Propagation, Memory, and Prediction: Insights from a Century of Magnetic ProxiesApr 10 2013The solar cycle and its associated magnetic activity are the main drivers behind changes in the interplanetary environment and the Earth's upper atmosphere (commonly referred to as space weather). These changes have a direct impact on the lifetime of ... More

Calibrating 100 Years of Polar Faculae Measurements: Implications for the Evolution of the Heliospheric Magnetic FieldMar 02 2013Although the Sun's polar magnetic fields are thought to provide important clues for understanding the 11-year sunspot cycle, including the observed variations of its amplitude and period, the current database of high-quality polar-field measurements spans ... More

The Role of Magnetic Topology in the Heating of Active Region Coronal LoopsSep 10 2010We investigate the evolution of coronal loop emission in the context of the coronal magnetic field topology. New modeling techniques allow us to investigate the magnetic field structure and energy release in active regions. Using these models and high ... More

Data-Optimized Coronal Field Model: I. Proof of ConceptApr 12 2019Deriving the strength and direction of the three-dimensional (3D) magnetic field in the solar atmosphere is fundamental for understanding its dynamics. Volume information on the magnetic field mostly relies on coupling 3D reconstruction methods with photospheric ... More

Solar Dynamics Observatory discovers thin high temperature strands in coronal active regionsJun 08 2011One scenario proposed to explain the million degrees solar corona is a finely-stranded corona where each strand is heated by a rapid pulse. However, such fine structure has neither been resolved through direct imaging observations nor conclusively shown ... More

Temperature and Emission-Measure Profiles Along Long-Lived Solar Coronal Loops Observed with TRACEMar 31 1999We report an initial study of temperature and emission measure distributions along four steady loops observed with the Transition Region and Coronal Explorer (TRACE) at the limb of the Sun. The temperature diagnostic is the filter ratio of the extreme-ultraviolet ... More

Magnetic Structure and Dynamics of the Erupting Solar Polar Crown Prominence on 2012 March 12May 26 2015We present an investigation of the polar crown prominence that erupted on 2012 March 12. This prominence is observed at the southeast limb by SDO/AIA (end-on view) and displays a quasi vertical-thread structure. Bright U-shape/horn-like structure is observed ... More

Hinode X-Ray Telescope Detection of Hot Emission from Quiescent Active Regions: A Nanoflare Signature?Jan 20 2009The X-Ray Telescope (XRT) on the Japanese/USA/UK {\it Hinode (Solar-B)} spacecraft has detected emission from a quiescent active region core that is consistent with nanoflare heating. The fluxes from 10 broadband X-ray filters and filter combinations ... More

Statistical study of network jets observed in the solar transition region: A comparison between coronal holes and quiet sun regionsApr 21 2016Recent IRIS observations have revealed a prevalence of intermittent small-scale jets with apparent speeds of 80 - 250 km s$^{-1}$, emanating from small-scale bright regions inside network boundaries of coronal holes. We find that these network jets appear ... More

Are Coronal Loops Isothermal or Multithermal? Yes!Jan 21 2009Surprisingly few solar coronal loops have been observed simultaneously with TRACE and SOHO/CDS, and even fewer analyses of these loops have been conducted and published. The SOHO Joint Observing Program 146 was designed in part to provide the simultaneous ... More

The Minimum of Solar Cycle 23: As Deep as It Could Be?Aug 05 2015In this work we introduce a new way of binning sunspot group data with the purpose of better understanding the impact of the solar cycle on sunspot properties and how this defined the characteristics of the extended minimum of cycle 23. Our approach assumes ... More

Motionless Phase Stepping in X-Ray Phase Contrast Imaging with a Compact SourceJul 08 2013X-ray phase contrast imaging offers a way to visualize the internal structures of an object without the need to deposit any radiation, and thereby alleviate the main concern in x-ray diagnostic imaging procedures today. Grating-based differential phase ... More

Hinode Calibration for Precise Image Co-alignment between SOT and XRT (November 2006 -- April 2007)Sep 26 2007To understand the physical mechanisms for activity and heating in the solar atmosphere, the magnetic coupling from the photosphere to the corona is an important piece of information from the Hinode observations, and therefore precise positional alignment ... More

Characterization of the Inner Knot of the Crab: The Site of the Gamma-ray Flares?Apr 17 2015One of the most intriguing results from the gamma-ray instruments in orbit has been the detection of powerful flares from the Crab Nebula. These flares challenge our understanding of pulsar wind nebulae and models for particle acceleration. We report ... More

Fitting and goodness-of-fit test of non-truncated and truncated power-law distributionsDec 20 2012Mar 11 2013Power-law distributions contain precious information about a large variety of processes in geoscience and elsewhere. Although there are sound theoretical grounds for these distributions, the empirical evidence in favor of power laws has been traditionally ... More

Prevalence of Small-scale Jets from the Networks of the Solar Transition Region and ChromosphereOct 22 2014Dec 22 2014As the interface between the Sun's photosphere and corona, the chromosphere and transition region play a key role in the formation and acceleration of the solar wind. Observations from the Interface Region Imaging Spectrograph reveal the prevalence of ... More

Scale Invariant Events and Dry Spells for Medium Resolution Local Rain DataDec 20 2012We analyze distributions of rain-event sizes, rain-event durations, and dry-spell durations for data obtained from a network of 20 rain gauges scattered in a region of the NW Mediterranean coast. While power-law distributions model the dry-spell durations ... More

High-resolution Observations of the Shock Wave Behavior for Sunspot Oscillations with the Interface Region Imaging SpectrographApr 24 2014Jun 17 2014We present the first results of sunspot oscillations from observations by the Interface Region Imaging Spectrograph. The strongly nonlinear oscillation is identified in both the slit-jaw images and the spectra of several emission lines formed in the transition ... More

Small-Scale and Global Dynamos and the Area and Flux Distributions of Active Regions, Sunspot Groups, and Sunspots: A Multi-Database StudyOct 23 2014Feb 10 2015In this work we take advantage of eleven different sunspot group, sunspot, and active region databases to characterize the area and flux distributions of photospheric magnetic structures. We find that, when taken separately, different databases are better ... More

Data-Driven Prediction of Thresholded Time Series of Rainfall and SOC modelsNov 09 2014We study the occurrence of events, subject to threshold, in a representative SOC sandpile model and in high-resolution rainfall data. The predictability in both systems is analyzed by means of a decision variable sensitive to event clustering, and the ... More

Testing Universality in Critical Exponents: the Case of RainfallAug 26 2015Mar 11 2016One of the key clues to consider rainfall as a self-organized critical phenomenon is the existence of power-law distributions for rain-event sizes. We have studied the problem of universality in the exponents of these distributions by means of a suitable ... More

Bogoliubov sound speed in periodically modulated Bose-Einstein condensatesAug 11 2003We study the Bogoliubov excitations of a Bose-condensed gas in an optical lattice. Of primary interest is the long wavelength phonon dispersion for both current-free and current-carrying condensates. We obtain the dispersion relation by carrying out a ... More

Intergalactic Gas in Groups of Galaxies: Implications for Dwarf Spheroidal Formation and The Missing Baryons ProblemJul 05 2011Radio galaxies with bent jets are predominantly located in groups and clusters of galaxies. We use bent-double radio sources, under the assumption that their jets are bent by ram-pressure, to probe intragroup medium (IGM) gas densities in galaxy groups. ... More

Bent-Double Radio Sources as Probes of the Intragroup MediumJul 25 2007Galaxy groups likely contain a significant fraction of the total baryonic mass in the local universe within their intragroup medium (IGM). However, aside from a handful of UV absorption line and X-ray observations, almost nothing is known about the IGM. ... More

Top Quarks at Photon CollidersSep 08 2000A review of results on top quark physics expected at the Photon Linear Colliders is presented.

The circumnuclear environment of IRAS 20551-4250 a case study of AGN/Starburst connection for JWSTDec 21 2011We present a general review of the current knowledge of IRAS 20551-4250 and its circumnuclear environment. This Ultraluminous Infrared Galaxy is one of the most puzzling sources of its class in the nearby Universe: the near-IR spectrum is typical of a ... More

Type-I superconductivity in ScGa3 and LuGa3 single crystalsMay 30 2012We present evidence of type-I superconductivity in single crystals of ScGa3 and LuGa3, from magnetization, specific heat, and resistivity measurements: low critical temperatures Tc = 2.1-2.2 K; field-induced secondto first-order phase transition in the ... More

A new evolution equationMar 20 1995We propose a new evolution equation for the gluon density relevant for the region of small $x_B$. It generalizes the GLR equation and allows deeper penetration in dense parton systems than the GLR equation does. This generalization consists of taking ... More

Self-Dual Supergravity Theories in 2+2 DimensionsJun 26 1992Starting from the new minimal multiplet of supergravity in $2+2$ dimensions, we construct two types of self-dual supergravity theories. One of them involves a self-duality condition on the Riemann curvature and implies the equations of motion following ... More

Twistor-like Formulation of Super p-BranesDec 21 1993Closed super (p+2)-forms in target superspace are relevant for the construction of the usual super p-brane actions. Here we construct closed super (p+1)-forms on a {\it worldvolume superspace}. They are built out of the pull-backs of the Kalb-Ramond super ... More

Exact exponential bounds for the random field maximum distribution via the majoring measures (generic chaining)Feb 04 2008In this paper non-asymptotic exact exponential estimates are derived for the tail of maximum distribution of random field in the terms of majoring measures or, equally, generic chaining.

The Hodge polynomial of \Mbar_{3,1}Oct 30 1999We give formulas for the Dolbeault numbers of \Mbar_{3,1}, using the first author's calculations of the weights of the cohomology of M_{2,2} and M_{2,3} and the second author's calculation of the weights of the cohomology of M_{3,1}.

A Note on `Hot Spot' Hunting in Deep-Inelastic ScatteringMay 27 1993We consider the inclusive cross section for jet production with large transverse momentum in deep-inelastic scattering. This process has been proposed as a probe of small-x physics, particularly the measurement of `hot spots' inside the proton. We present ... More

Numerical invariants for bundles on blow-upsJun 26 1999We suggest an effective procedure to calculate numerical invariants for rank two bundles over blown-up surfaces. We study the moduli spaces M_j of bundles on the blown-up plane splitting over the exceptional divisor as O(j)+O(-j). We use the numerical ... More

Can there be a general nonlinear PDE theory for the existence of solutions ?Jul 02 2004Contrary to widespread perception, there is ever since 1994 a unified, general type independent theory for the existence of solutions for very large classes of nonlinear systems of PDEs. This solution method is based on the Dedekind order completion of ... More

Short introduction to Nonstandard AnalysisJul 10 2004These lecture notes, to be completed in a later version, offer a short and rigorous introduction to Nostandard Analysis, mainly aimed to reach to a presentation of the basics of Loeb integration, and in particular, Loeb measures. The Abraham Robinson ... More

Two problems in Classical MechanicsJul 09 2004A problem about the present structure of dimensional analysis, and another one about the differences between solids and fluids are suggested. Both problems appear to have certain foundational aspects.

Playing with the enveloping algebra of supersymmetryJul 20 2016Oct 17 2016In this paper we show how to obtain from a scalar superfield its first component via a similarity transformation. We prove that in D=4 the generators of this similarity transformation live in the enveloping algebra of supersymmetry while for D=1 they ... More

The Average Temporal and Spectral Evolution of Gamma-Ray BurstsDec 26 1997We have averaged bright BATSE bursts to uncover the average overall temporal and spectral evolution of gamma-ray bursts (GRBs). We align the temporal structure of each burst by setting its duration to a standard duration, which we call T_<Dur>. The observed ... More

On the Shafarevich conjecture for surfaces of general type over function fieldsApr 22 1999Apr 30 1999For a non-isotrivial family of surfaces of general type over a complex projective curve, we give upper bounds for the degree of the direct images of powers of the relative dualizing sheaf. They imply that, fixing the curve and the possible degeneration ... More

A Subjective Approach to Quantum ProbabilityMar 06 2005A likelihood order is defined over linear subspaces of a finite dimensional Hilbert space. It is shown that such an order that satisfies some plausible axioms can be represented by a quantum probability in two cases: pure state and uniform measure.

Gauge Invariant Classes of Feynman Diagrams and Applications for CalculationsJan 24 2001In theories like SM or MSSM with a complex gauge group structure the complete set of Feynman diagrams contributed to a particular physics process can be splited to exact gauge invariant subsets. Arguments and examples given in the review demonstrate that ... More

Off shell pi N amplitude and the p p->p p pi0 reactionMar 21 1995We have used a conventional model for the $pp \rightarrow pp \pi^{0}$ reaction consisting of the Born term plus the $s$-wave rescattering term. As a novelty we have introduced the off shell dependence of the $\pi N$ $s$-wave isoscalar amplitude. This ... More

A question in the axiomatic approach to Quantum MechanicsJul 09 2004The classical Hilbert space formulation of the axioms of Quantum Mechanics appears to leave open the question whether the Hermitian operators which are associated with the observables of a finite non-relativistic quantum system are uniquely determined. ... More

Tame division algebras of prime period over function fields of $p$-adic curvesMar 09 2010Mar 30 2012Let F be a field of transcendence degree one over a p-adic field, and let l be a prime not equal to p. Results of Merkurjev and Saltman show that H^2(F,\mu_l) is generated by Z/l-cyclic classes. We prove the "Z/l-length" in H^2(F,\mu_l) equals the l-Brauer ... More

Functional limit theorems for Levy processes and their almost-sure versionsAug 07 2009In this paper we prove a criterion of convergence in distribution in Skorokhod space. We apply this criterion to some special Levy processes and obtain almost-sure versions of limit theorems for these processes.

Topologies and all that -- A TutorialMar 03 2015This is a brief introduction to the basic concepts of topology. It includes the basic constructions, discusses separation properties, metric and pseudometric spaces, and gives some applications arising from the use of topology in computing.

On certain definite integrals and infinite seriesSep 23 2013A translation of Kummer`s paper On certain definite integrals and infinite series

Quasielastic Versus Inelastic and Deep Inelastic Lepton Scattering in Nuclei at x > 1Dec 12 1996Feb 14 1997We have made a thorough investigation of the nuclear structure function W_2A in the region of 0.8 < x < 1.5 and Q^2 < 20 GeV^2, separating the quasielastic and inelastic plus deep inelastic contributions. The agreement with present experimental data is ... More

Isocalar Roper excitation in the pp --> pp pi0 reaction close to thresholdAug 07 1998A new mechanism for the pp --> pp pi0 reaction close to threshold is suggested coming from the isoscalar excitation of the Roper and its decay into N(pi pi)S-wave, with one of the pi0 emitted and the other one reabsorbed on the second nucleon. The mechanism ... More

Basics of Quantum Computation (Part 1)Jul 08 2004The aim of this textbook is to bridge in regard of quantum computation what proves to be a considerable threshold even to the usual science trained readership between the level of science popularization, and on the other hand, the presently available ... More

Perturbative QCD and beyond: azimuthal angle correlations in deuteron-deuteron scattering from Bose-Einstein correlationsNov 05 2016In this paper, we found within the framework of perturbative QCD, that in deuteron-deuteron scattering the Bose-Einstein correlations due to two parton showers production, induce azimuthal angle correlations, with three correlation lengths: the size of ... More

Gamma-Ray Burst Spectra and Time Histories from 2 to 400 keVFeb 12 1998The Gamma-Ray burst detector on Ginga consisted of a proportional counter to observe the x-rays and a scintillation counter to observe the gamma-rays. It was ideally suited to study the x-rays associated with gamma-ray bursts (GRBs). Ginga detected 120 ... More

A continuous analogue of the invariance principle and its almost sure versionAug 07 2009We deal with random processes obtained from a homogeneous random process with independent increments by replacement of the time scale and by multiplication by a norming constant. We prove the convergence in distribution of these processes to Wiener process ... More

How to solve smooth nonlinear PDEs in algebras of generalized functions with dense singularitiesJun 29 2004As a significant strengthening of properties of earlier algebras of generalized functions, here are presented classes of such algebras which can deal with dense singularities. In fact, the cardinal of the set of singular points can be larger than that ... More

A set-indexed fractional Brownian motionMar 11 2005Feb 06 2006We define and prove the existence of a fractional Brownian motion indexed by a collection of closed subsets of a measure space. This process is a generalization of the set-indexed Brownian motion, when the condition of independance is relaxed. Relations ... More

Mesonic and Binding Contributions to the Nuclear Drell-Yan ProcessDec 01 1997We have evaluated the Drell-Yan cross section in nuclei paying special attention to the meson cloud contribution from pion and rho-meson, for which an accurate calculation using the meson nuclear spectral functions is used. Similarly, the nucleonic contribution ... More

On the stationarity of linearly forced turbulence in finite domainsApr 28 2011May 08 2011A simple scheme of forcing turbulence away from decay was introduced by Lundgren some time ago, the `linear forcing', which amounts to a force term linear in the velocity field with a constant coefficient. The evolution of linearly forced turbulence towards ... More

On non-linear superfield versions of the vector-tensor multipletNov 06 1997Jan 30 1998We propose a harmonic superspace description of the non-linear vector-tensor N=2 multiplet. We show that there exist two inequivalent version: the old one in which one of the vectors is the field-strength of a gauge two-form, and a new one in which this ... More

Chiral fermion action with (8,0) worldsheet supersymmetryJun 13 1994We propose an action describing chiral fermions with an arbitrary gauge group and with manifest $(8,0)$ worldsheet supersymmetry. The form of the action is inspired by and adapted for completing the twistor-like formulation of the $D=10$ heterotic superstring. ... More

Limits on Expanding Relativistic Shells from Gamma-Ray Burst Temporal StructureMay 06 1997We calculate the expected envelope of emission for relativistic shells under the assumption of local spherical symmetry. Gamma-Ray Burst envelopes rarely conform to the expected shape, which is similar to a FRED; a fast rise and exponential decay. The ... More

Thermal radiation and inclusive production in the CGC/saturation approach at high energiesFeb 21 2019In this paper, we discuss the inclusive production of hadrons in the framework of CGC/saturation approach. We argue, that the gluon jet inclusive production stems from the vicinity of the saturation momentum, even for small values of the transverse momenta ... More

Super p-Brane Theories and New Spacetime SuperalgebrasApr 26 1995We present a geometric formulation of super $p$--brane theories in which the Wess--Zumino term is $(p+1)$--th order in the supersymmetric currents, and hence is manifestly supersymmetric. The currents are constructed using a supergroup manifold corresponding ... More

Proximity effect and self-consistent field in a normal metal-superconductor structureMar 12 2019The concept of a self-consistent field in the theory of superconductivity based on the diagram method of the time-dependent perturbation theory is presented. It is shown that the well-known Bardeen-Cooper-Schrieffer equation for the order parameter of ... More

An analysis of numerical issues in neural training by pseudoinversionAug 25 2015Some novel strategies have recently been proposed for single hidden layer neural network training that set randomly the weights from input to hidden layer, while weights from hidden to output layer are analytically determined by pseudoinversion. These ... More

HST revisits the proper motion of PSR B0656+14May 08 2000May 09 2000We report the first successful measurement (with HST/WFPC2) of a significant proper motion for a V~ 25 object which we had proposed as the optical counterpart of the radio pulsar PSR B0656+14. The yearly displacement of 43+/- 2 mas is highly significant ... More

Temporal Evolution of the Pulse Width in GRBsDec 23 1998Many cosmological models of GRBs envision the energy source to be a cataclysmic stellar event leading to a relativistically expanding fireball. Particles are thought to be accelerated at shocks and produce nonthermal radiation. The highly variable temporal ... More

The Observational Basis for Central Engines in Gamma Ray BurstsJun 08 1999We review the observational differences between gamma-ray bursts occurring on a single shell (such as in the external shock model) and multiple shells (such as in the internal shock model). We do not argue against external shocks or for internal shocks, ... More

Couplings of self-dual tensor multiplet in six dimensionsMay 13 1996The (1,0) supersymmetry in six dimensions admits a tensor multiplet which contains a second-rank antisymmetric tensor field with a self-dual field strength and a dilaton. We describe the fully supersymmetric coupling of this multiplet to Yang-Mills multiplet, ... More

Science Objectives for an X-Ray Microcalorimeter Observing the SunNov 17 2010We present the science case for a broadband X-ray imager with high-resolution spectroscopy, including simulations of X-ray spectral diagnostics of both active regions and solar flares. This is part of a trilogy of white papers discussing science, instrument ... More

The conformal transformation of the night skyJun 24 2016We give a simple differential geometric proof of the conformal transformation of the night sky under change of observer. The proof does not rely on the four dimensionality of spacetime or on spinor methods. Furthermore, it really shows that the result ... More

Spectral properties of weighted line digraphsJun 09 2015In this paper, we treat some weighted line digraphs which are induced by a connected and undirected graph. For a given graph $G$, the adjacency matrix of the weighted line digraph $W$ is determined by a boundary operator from an arc-based space to a vertex-based ... More

A Hardware Implementation of Artificial Neural Network Using Field Programmable Gate ArraysMar 05 2007An artificial neural network algorithm is implemented using a field programmable gate array hardware. One hidden layer is used in the feed-forward neural network structure in order to discriminate one class of patterns from the other class in real time. ... More

Semileptonic b to u transitionFeb 12 2007Experimental studies of charmless semileptonic B decays can be broadly categorized into inclusive and exclusive measurements depending on how the final states are treated. The inclusive method measures the decay rate $\Gamma(B \to X_u \ell \nu)$, where ... More

Reply to the comment by D. Gorokhov cond-mat/0502083Feb 09 2005We show that the recent comment by D. Gorokhov, is based on physically obvious errors and misunderstandings of the content of the criticized papers and is readily refuted. We show that 1) In our paper [1] there were considered situations of both strong ... More

Supersymmetric radiative corrections to neutrino indices of refractionJun 02 1995We compute the one-loop effects on the neutrino propagation through matter induced by virtual supersymmetric particles. We show that, in the minimal version of the supersymmetric standard model, a non-degeneracy between sleptons of the second and third ... More

Spiralicity and Motion on Cosmic ScaleJun 25 2014We hypothesize a simple scenario to associate spiral-shaped trajectories and asymptotic tangential velocities according to observations found on deep space scales. As a difference with alternative Modified Newton Dynamics (MoND), in our scenario the dynamics ... More

Special relativity as the limit of an Aristotelian universal friction theory under Reye's assumptionNov 28 2014This work explores a classical mechanical theory under two further assumptions: (a) there is a universal dry friction force (Aristotelian mechanics), and (b) the variation of the mass of a body due to wear is proportional to the work done by the friction ... More

Interactions between hadrons are strongly modified near the QCD (tri)critical pointApr 06 2005The QCD (tri)critical point, a genuine second-order phase transition, implies existence of a massless scalar mode, and singular behavior near it. In this work we however focus on the finite region around it, defined by a condition $m_\sigma=2m_\pi$. We ... More

Convexity and quasi-uniformizability of closed preordered spacesDec 16 2012Mar 17 2013In many applications it is important to establish if a given topological preordered space has a topology and a preorder which can be recovered from the set of continuous isotone functions. Under antisymmetry this property, also known as quasi-uniformizability, ... More

Functional spaces and operators connected with some Lévy noisesAug 15 2006We review some recent developments in white noise analysis and quantum probability. We pay a special attention to spaces of test and generalized functionals of some L\'evy white noises, as well as as to the structure of quantum white noise on these spaces. ... More

The Associated Metric for a Particle in a Quantum Energy LevelMar 24 1997Jul 04 1997We show that the probabilistic distribution over the space in the spectator world, can be associated via noncommutative geometry (with some modifications) to a metric in which the particle lives. According to this geometrical view, the metric in the particle ... More

On the Possibility of an Astronomical Perspective in the Study of Human EvolutionDec 05 2013The Sapient Paradox is the apparently unexplainable time delay of several ten thousand years following the arrival of Homo sapiens in Asia and Europe and before the introduction of impressive innovations with the agricultural revolution. Renfrew (2007) ... More