Miracle-dz/UniFAR-FTUs huggingface dataset:
Core-Halo Distribution Functions: A Natural Equilibrium State in Generalized Thermostatistics

Space observations provide a clear signature of non-Maxwellian core-halo electron and ion-velocity distribution functions as an ubiquitous and persistent feature of astrophysical plasma environments. In particular, the detected suprathermal halo populations are accurately represented by the family of κ-distributions, a power law in particle speed. Contrary to observations, the physical relevance of κ-distributions has frequently been criticized because of a lack of theoretical justification. We show that these distributions turn out as consequence of an entropy generalization based on nonextensive thermostatistics, thus providing the missing link for power-law models from fundamental physics. Moreover, upon clarifying that the full nonextensive formalism is also compatible with negative values of the spectral index κ, we demonstrate that core-halo structures are a natural element within pseudoadditive entropy. As a consequence, pronounced core-halo patterns can be generated adiabatically, following density conservation out of a Maxwellian equilibrium state. The physical significance of the proposed nonextensive double-κ distribution family is analyzed with regard to nonthermal entropy evolution and tested on typical core-halo characteristics of observed interplanetary electron and ion velocity space structures, originating as a natural equilibrium state within the generalized entropy concept. The peak separation scale of interplanetary double-humped proton distributions is found to obey a maximum entropy condition.
Formulation of the eddy current problem in multiply connected regions in terms of h

In this paper various formulations for the eddy current problem are presented. The formulations are based on solving directly for the magnetic field h, and they differ from each other mainly by how the field on the boundary is treated. The electromagnetic problem is studied in connection with the fivefold decomposition of the space of square integrable vector fields within a bounded region. This provides us with numerical approaches with clear signposts about how to solve the eddy current problem in multiply connected domains. Besides the fivefold decomposition, another essential tool in our approach is Whitney elements, as they provide the structure needed to retain consistency between the continuous and discrete problems. The paper demonstrates the usefulness of these mathematical tools in solving electromagnetic field problems. © 1998 John Wiley & Sons, Ltd.
A Theory Describing Sedimentation Particulate Fouling Thresholds Inside Heat Exchanger Tubes

This paper expounds a simple, fundamental theory for predicting sedimentation particulate fouling thresholds for horizontal flows inside heat exchanger tubes. The velocities and shear stresses at the tube wall predicted by this theory for keeping particulate matter suspended compare favorably with industrial experience and proprietary Chevron data. This theory is also not inconsistent with the literature in that the shear stress required for sedimentation fouling mitigation is roughly 4–6 Pa. However, the situation where small particles become encapsulated in the viscous sublayer cannot be resolved with a simple sedimentation particulate fouling threshold theory at this time, necessitating future research.
Chemical abundances for cyanogen-weak giants

Atmospheric parameters and detailed chemical abundances are derived for 30 cyanogen-weak giants. The (Fe/H) ratios range from -1.2 to 0.2, show a mean value of {minus}0.20, and have an estimated internal uncertainty of + or - 0.2. Most of the stars have a modern spectral designation of Fe({minus}); this designation correlates only weakly with the derived (Fe/H) ratio. Light-element abundances and C-12/C-13 ratios are determined for the complete sample. The CNO abundances normalized to Fe collectively do not deviate substantially from that of normal K giants. 94 refs.
The HST quasar absorption line key project. 4: HST faint-object spectrograph and ground-based observations of the unusual low-redshift broad absorption-line quasi-stellar object PG 0043+039

Hubble Space Telescope Faint Object Spectrograph (HST FOS) observations have shown that the spectrum of the low-redshift (z(sub em) approximately equal to 0.384) QSO PG 0043+039 exhibits weak broad absorption lines (BALs). The BALs were discovered during the course of UV spectrophotometry made for the HST Quasar Absorption Line Key Project. The HST data are analyzed along with ground-based optical and IUE spectrophotometry. The object is found to have a number of atypical properties relative to normal non-BAL QSOs. The observed continuum is atypical in the sense that it is much weaker than that of a normal optically selected QSO at rest wavelengths approximately less than 2200 A. Intrinsic reddening of E(B-V) approximately equal to 0.11 mag by dust similar to that found in the SMC at the redshift of PG 0043+039 conservatively accounts for the observed continuum shape moderately well. These observed characteristics are typical of low-ionization BAL QSOs, but convincing evidence for BALs due to low-ionization transitions of Mg II, Al III, Al II, or C II does not exist. Therefore, this object may be a misaligned BAL QSO having many of the characteristics of low-ionization BAL QSOs with the sight line passing through a putative dusty region, but evidently missing clouds of high enough column density to produce observable low-ionization BALs. If the intrinsic dust-extinction model is correct, the observations suggest that the dust is not confined to the presumably higher density, low-ionization BAL clouds, but that it has drifted to nearby high-ionization BAL regions. We also consider other possible mechanisms for producing the shape of the continuous energy distribution which cannot be ruled out. We compare the Fe II emission in PG 0043+039 with that in another Key Project QSO, NGC 2841-UB 3, which has optical Fe II emission comparable in strength to that in PG 0043+039, but has anomalously weak UV Fe II emission. In addition, from an analysis of UV and optical spectrophotometric data at 5 epochs over approximately 11 yr, there is tentative evidence that PG 0043+039 has varied in brightness by as much as 1.1 mag during this time interval. Two different interpretations of PG 0043+039 and the low-ionization BAL QSOs are considered. Various model scenarios for explaining the weak narrow-line (O III) emission are considered, but there is no definitive explanation.
Prediction, Explanation, and Testability as Criteria for Judging Statistical Theories

For the case of statistical theories, the criteria of explanation, prediction, and testability can all be viewed as particular instances of a more general evaluation scheme. Using the ideas of a gain matrix and expected gain from statistical decision theory, these three criteria can be compared in terms of the elements in their associated gain matrices. This analysis leads to (1) further understanding of the interrelationship between the current criteria, (2) the proposal of an ordering for the criteria, and (3) the suggestion of a new criterion.
Thermally, mechanically or externally driven flows in a gas centrifuge with insulated horizontal end plates

The axisymmetric motion of a compressible fluid in a rapidly rotating cylinder is considered using a linear approach and boundary-layer techniques. The deviation of the fluid motion from rigid-body rotation is caused either by an applied temperature distribution on the side wall, a differential rotation of the top and bottom end plates or sources and sinks of fluid distributed on the end plates. The horizontal end plates are assumed to be thermally insulated, while the side wall is conducting. The critical parameter governing the problem is found to be E−½(γ − 1) PrG0/4γ, where E is the Ekman number, γ the ratio of specific heats, Pr the Prandtl number and G0 the square of a rotational Mach number. If this parameter is larger than unity, the coupled effect of the compressibility of the fluid and the thermal condition on the end plates suppresses the flow in the cylinder. The flow in the inner inviscid core is strongly coupled with the Ekman-layer flow through the boundary conditions on the end plates, something which does not occur if the fluid is Boussinesq nor if the fluid is compressible and the end plates are conducting.
Hard X-ray light curves of high-mass X-ray binaries

Using the 7.2 years of continuous data now available from the Burst And Transient Source Experiment (BATSE) aboard CGRO, we have measured orbital periods and produced folded lightcurves for 8 High Mass X-ray Binaries (HMXB). Given the length of the datasets, our determinations are based on many more binary orbits than previous investigations. Thus our source detections have high statistical significance and we are able to follow long-term trends in X-ray output. In particular we focus on two systems: A0538-668 and EXO2030+375 both HMXBs exhibiting Type I outbursts. Recent work on A0538-668 (Alcock et al 1999) reported a 16.65d optical variability due to the orbital period, but only seen during minima of a longer-term variability at 421d. We searched for this signal in the BATSE dataset using an ephemeris derived from Alcock et al ( 1999) & Skinner ( 1982). We found no evidence for such modulation and place an upper limit of 3.0 x 10(exp -3) photon/sq cm.s in the 20-70 keV BATSE energy band , based upon statistical modelling of the signal. EXO2030+375 has exhibited an X-ray active epoch, followed by a quiescent period lasting 2.5yr and since April 1996 has exhibited renewed activity. Previous observations (Reig et a 1998) using RXTE ASM data indicate secondary outbursts occur at apastron passage during the current epoch, but not in the former. We present a lightcurve for the earlier epoch showing convincing evidence for such apastron outbursts. We find apastron outbursts in 3 sources, all having orbital periods greater than 41d. No such signal is conclusively detected in the more rapidly orbiting systems studied.
Heat Transfer From a Flat Plate to a Fully Developed Axisymmetric Impinging Jet

Impinging jets have been used in a number of applications to enhance heat and mass transfer; this includes cooling steel plates, the tempering of glass, drying papers and films, cooling turbine blades, cooling electronic components, etc. Studies have included the effects of Reynolds number, nozzle-to-plate distance, nozzle geometry, jet temperature, orientation, multiple jets, crossflow, and impinging surface shape on the resulting flow and heat transfer. Critical reviews of impinging jet heat transfer studies have been published. Martin, Jambunathan et al., and Viskanta reviewed the heat transfer data for single jets and for arrays of axisymmetric and planar jets. Heat transfer measurements for various nozzle geometries and flow conditions have been made and studied the heat transfer characteristics for a turbulent air jet issuing from an elliptical nozzle.
Comparisons of Single- and Double-Moment Microphysics Schemes in the Simulation of a Synoptic-Scale Snowfall Event

AbstractThe Canadian CloudSat/Cloud–Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) Validation Project (C3VP) provided aircraft, surface, and remotely sensed observations of cloud and precipitation characteristics to support improved simulation of cold-season precipitation within weather forecast models and new developments in satellite and radar precipitation retrievals. On 22 January 2007, the C3VP campaign executed an intensive observation period to sample widespread snowfall that occurred as a midlatitude cyclone tracked along the U.S.–Canadian border. Surface air temperature and precipitation measurements, combined with aircraft measurement of hydrometeor content and size distribution, are used to examine various assumptions and parameterizations included within four bulk water microphysics schemes available within the Weather Research and Forecasting Model (WRF). In a simulation of the 22 January 2007 event, WRF forecasts reproduced the overall precipitation pattern observed du.
X‐ray photoelectron spectroscopy study of hydrogen plasma interactions with a tin oxide surface

Tin oxide thin films were exposed to an rf excited hydrogen plasma (100 mTorr) for various times. The plasma system was operated in a self‐biased mode. X‐ray photoelectron spectroscopy analysis of vacuum transferred samples shows that SnO2 is reduced. A thin self‐limiting layer of elemental Sn forms on the reduced film to a thickness of ∼10 A.
BD ANDROMEDAE: A NEW SHORT-PERIOD RS CVn ECLIPSING BINARY STAR WITH A DISTANT TERTIARY BODY IN A HIGHLY ECCENTRIC ORBIT

A photometric study of BD And was made through the analysis of two sets of new BVR light curves. The light curves with migrating photometric waves outside eclipse show that BD And is a short-period RS CVn-type binary star. The analysis of all available timings reveals that the orbital period has varied in a strictly cyclical way with a period of 9.2 yr. The periodic variation most likely arises from the light-time effect due to a tertiary moving in a highly elliptical orbit (e3 = 0.76). The Applegate mechanism could not operate properly in the eclipsing pair. The light curves were modeled with two large spots on the hotter star and a large third light amounting to about 14% of the total systemic light. BD And is a triple system: a detached binary system consisting of two nearly equal solar-type stars with an active primary star and a G6–G7 tertiary dwarf. The absolute dimensions of the eclipsing pair and tertiary components were determined. The three components with a mean age of about 5.8 Gyr are located at midpositions in main-sequence bands. The radius of the secondary is about 17% larger than that deduced from stellar models. The orbital and radiometric characteristics of the tertiary are intensively investigated. One important feature is that the mutual inclination between two orbits is larger than 60°, implying that Kozai cycles had occurred very efficiently in the past. The possible past and future evolutions of the BD And system, driven by KCTF and MBTF, are also discussed.
Estimation of wood biomass in the Jubba Valley, southern Somalia, and its application to East African rangelands

Summary A comparative analysis was made of regression equations relating wood biomass (above-ground) of individual trees to their canopy dimensions in semi-arid rangelands of East Africa. ‘Best estimates’ of wood biomass of bushlands and woodlands in the Jubba Valley of southern Somalia were derived using these relationships. Bushlands carry 1–30 kg ha-1 dry weight of wood, woodlands 2–75 kg ha-1. Subdivision of bushland and woodland categories by density of wood canopy gives finer subdivisions of biomass categories. While the statistical precision and accuracy of these estimates cannot be derived, critical comparison with other studies suggests that these wood biomass estimates may be more widely applicable in East Africa. However, a much more site-specific inventory is required to confirm the accuracy of these estimates. Resume On a fait une analyse comparative des equations de regression reliant la biomasse ligneuse de chaque arbre a la dimension de sa canopee, dans un biotope semi-aride d'Afrique de l'Est. En se servant de ces relations, on a derive les ‘meilleures estimations’ de biomasse de bois en brousse et en foret dans la Juba Valley, dans le sud de la Somalie. Les milieux buissonneux supportent 1–30 kg/ha de poids sec de bois, les forets, 2–75 kg/ha. La subdivision des categories zones buissonneuses et forets par la densite de canopee boisee donne une analyse plus fine des categories de biomasse. Puisque la precision statistique et l'exactitude de ces evaluations ne peuvent etre derivees, une comparaison critique avec d'autres etudes suggere que ces estimations de biomasse ligneuse peuvent etre plus largement applicables en Afrique de l'Est. Mais il faut faire un inventaire beaucoup plus specifique de l'endroit pour confirmer l'exactitude de ces estimations.
Gene delivery in conjunction with gold nanoparticle and tumor treating electric field

The advances in electrotherapy to treat the diseased biological cell instigate its extension in gene therapy through the delivery of gene into the nucleus. The objective of this study is to investigate the application of moderate intensity alternating electric field, also known as tumor treating electric field on a carrier system consisting of a charged gene complex conjugated to the surface of a gold nanoparticle. The gene delivery mechanism relies on the magnitude and direction of the induced electric field inside the cytoplasm in presence of carrier system. The induced electric field strength is significant in breaking the gene complex-gold nanoparticle bonding, and exerting an electric force pushing the charged gene into the nucleus. The electric force orientation is dependent on the aspect ratio (AR) of the gold nanoparticle and a relationship between them is studied via Maxwell two-dimensional (2D) finite element simulation analyzer. The development of charge density on the surface of carrier system.
Spectroscopic diagnostics of T Tauri inner winds

Abstract The role of the star-disk interaction region in launching the high velocity component of accretion-driven outflows is examined. Spectroscopic indicators of high velocity inner winds have been recognized in T Tauri stars for decades, but identifying the wind launch site and the accompanying mass loss rates has remained elusive. A promising new diagnostic is He I λ10830, whose metastable lower level results in a powerful probe of the geometry of the outflowing gas in the interaction region. This, together with other atomic and molecular spectral diagnostics covering a wide range of excitation and ionization states, suggests that more than one launch site of the innermost wind is operational in most accreting stars.
Detection of monochromatic photons between 50 and 790 MeV with a PbWO/sub 4/-scintillator array

The performance of PbWO/sub 4/ as a fast and compact scintillator material for calorimetry at energies well below 1 GeV has been investigated using a collimated beam of monoenergetic photons with an energy between 50 and 790 MeV provided by the tagged photon facility of MAMI at Mainz. In continuation of previous experiments with electrons, a larger matrix of 5/spl times/5 PbWO/sub 4/-crystals (20/spl times/20/spl times/150-200 mm/sup 3/) has been used to reconstruct the electromagnetic shower. The scintillators were selected according to their optical quality and response to low energy /spl gamma/-sources. The array was operated at a stabilized temperature of T=8/spl deg/C and read-out individually by photomultiplier tubes. The achieved excellent energy resolution amounts to /spl sigma//E=1.54%//spl radic/E+0.30% (E given in GeV) and has proven the applicability of PbWO/sub 4/ as a high quality scintillator material even at medium energies. The experimental data have been reproduced by GEANT3 simulations.
Helioseismic evidence of two solar granulation timescales

The signature of two different scales of solar granulation in the power spectrum of disk integrated irradiance time series is presented. The fitted timescales for granulation (τGR1 ≈ 237 s and τGR2 ≈ 62 s) are in good agreement with the characteristic lifetimes derived from recent image time series of the Sun’s surface (Del Moro 2004); and probably linked to magnetic chromospheric structures such as bright points (Harvey et al. 1993).
General relativity via complete integrals of the Hamilton–Jacobi equation

The aim of this work is to present a formulation to general relativity, which is analogous to the null surface formulation, but now instead of starting with a complete integral of the eikonal equation we start with a complete integral of the Hamilton–Jacobi equation. In the first part of this work we show that on the space of solutions of a certain class of systems of six second-order partial differential equations, uss=Λ(s,s*,γ,u,us,us*,uγ),us*s*=Λ*(s,s*,γ,u,us,us*,uγ), uγγ=Υ(s,s*,γ,u,us,us*,uγ),uss*=Φ(s,s*,γ,u,us,us*,uγ), usγ=Ψ(s,s*,γ,u,us,us*,uγ),us*γ=Ψ*(s,s*,γ,u,us,us*,uγ), a four-dimensional (definite or indefinite) metric, gab, can be constructed on the four-dimensional solution space with local coordinates xa. Furthermore the solutions, u=Z(xa,s,s*,γ), satisfy the four-dimensional Hamilton–Jacobi equation, gabu,au,b=1. We remark that this structure is invariant under a subset of contact transformations. In the next section, as an example, we apply these results to the Schwarzschild metric. Finally .
High redshift Lyα halos

We review current evidence for the existence of large emission-line halos around high redshift radio galaxies. Detailed narrow-band imaging and spectroscopic studies of these systems may help us understand the early stages of massive forming galaxies and AGN feedback. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
HST/STIS imaging of Fomalhaut: New main belt structure and confirmation of Fomalhaut b's eccentric orbit

Abstract High contrast imaging observations with the Hubble Space Telescope show that the nearby star Fomalhaut is surrounded by a dusty debris belt and a candidate planet, Fomalhaut b, located just inside the edge of the belt. Fomalhaut b has unexpected characteristics, such as a relatively blue spectrum, leading to the hypothesis that the detected object is a low-mass planet hosting a giant planetary dust ring or cloud seen in reflected light. Here we present new HST/STIS observations made in 2010 and 2012 that authenticate the existence of Fomalhaut b. Our MCMC analysis of four epochs of astrometry spread over eight years indicate that the orbit has a~170 AU and e~0.85. Fomalhaut b's orbit is apsidally aligned with the main belt, and periapse is located approximately ~30 AU south of the star. We also show the existence of a ~50 AU wide azimuthal dust depletion in the dust belt. These new findings provide a revised picture of Fomalhaut as a dynamically complex system, where the orbit of Fomalhaut b and the belt structure signify the presence of additional massive planets orbiting the star.
The sensitivity of large‐eddy simulations of shallow cumulus convection to resolution and subgrid model

Results are presented from a series of large‐eddy simulations of shallow cumulus convection, including some at much higher resolution than previously performed. Many of the ensemble‐averaged turbulence statistics which are relevant for mass‐flux parametrization schemes are shown to be reasonably insensitive to increases in resolution, but the cloud fields change markedly. the implications for the best interpretation of large‐eddy simulation results are discussed.
On Gruenhage spaces, separating σ -isolated families, and their relatives

Weprovethat,givenatopologicalspace X ,thefollowingconditionsareequivalent. ( α ) X is a Gruenhage space. ( β ) X has a countable cover by sets of small local diameter (property SLD) by F ∩ G sets. ( γ ) X has a separating σ -isolated family M ⊂ F ∩ G . ( δ ) X has a one-to-one continuous map into a metric space which has a σ -isolated base of F ∩ G sets. Besides, we provide an example which shows Fragmentability (cid:2) property SLD (cid:2) the space to be Gruenhage.