Energy Spectra

We compute the energy spectra of the gravitational signals emitted when a mass m 0 is scattered by the gravitational field of a star of mass M >> m 0 . We show that, unlike black holes in similar processes, the quasi-normal modes of the star are excited, and that the amount of energy emitted in these modes depends on how close the exciting mass can get to the star.

The silicon matrix detector is the charge measuring system of the Advanced Thin Ionization Calorimeter (ATIC). ATIC is designed to measure the elemental energy spectra of Galactic cosmic rays at energies above 50 GeV/nuc. The silicon matrix must determine the elemental identity of each incident cosmic ray in the presence of backscatter from the interactions of those cosmic rays in ATIC's calorimeter. To accomplish this, the matrix is a mosaic of 4480 silicon detector pads, each 1.5 cm by 2 cm. Each pad is individually readout and pulse height analyzed. The design of the matrix will be described and the results from a CERN accelerator calibration will be presented.

The Advanced Thin Ionization Calorimeter (ATIC) is a balloon borne experiment to measure the composition and energy spectra of Z = 1 to 28 cosmic rays over the energy range ∼ 30 GeV -100 TeV. The instrument consists of a fully active 320-crystal Bismuth Germanate (BGO) calorimeter, 202 scintillator strips in 3 hodoscopes interleaved with a graphite target, and a 4480-pixel silicon matrix charge detector. ATIC has had two successful Long Duration Balloon flights from McMurdo, Antarctica: from 12/28/00 to 01/13/01 and from 12/29/02 to 01/18/03. We have developed the ATIC Data Processing Syetem (ADPS), which is an Object Oriented data processing program based on ROOT. In this paper, we describe the processing scheme used in handling the flight data, especially the calibration method and the event reconstruction algorithm.

The Advanced Thin Ionization Calorimeter (ATIC) balloon experiment completed a 19.7 day science flight, 29 Dec. 02 to 18 Jan. 03, from McMurdo, Antarctica, yielding 67 Gbytes of science data. The instrument was fully recovered just over the trans-Antarctic mountain range. ATIC is designed to make new measurements of the composition and energy spectra of cosmic rays in the region up to 100 TeV total energy. The flight and the instrument performance are described and compared to the ATIC-1 flight from 2000-01, and some preliminary results are discussed.

The results of ATIC-2 baloon experiment (2002)(2003) for energy spectra of protons, He, C, O, Ne, Mg, Si, Fe, some groups of nuclei, and all-particle spectrum in primary cosmic rays are presented in energy region 50 GeV-200 TeV. The conclusion is that the spectra of protons and helium nuclei are essentially different (the spectrum of protons is steeper) and the spectra of protons and heavy nuclei have no-power form.

The preliminary energy spectra of heavy nuclei C, O, Ne, Mg, Si, and Fe in the primary cosmic rays measured by the ATIC-2 experiment are presented and compared to previous data and to propagation models. Using previous data to extend the ATIC-2 results for all heavy nuclei to higher energy, the combined spectra can be best fit with diffusion model with weak reacceleration and scattering on random magnetic field with a Kolmogorov spectrum fluctuations becoming dominant at high energy.

Long Duration Balloon (LDB) scientific experiments, launched to circumnavigate the south pole over Antarctica, have particular advantages compared to Shuttle or other Low Earth Orbit (LEO) missions in terms of cost, weight, scientific "duty factor" and work force development. The Advanced Thin Ionization Calorimeter (ATIC) cosmic ray astrophysics experiment is a good example of a university-based project that takes full advantage of current LDB capability. The ATIC experiment is currently being prepared for its first LDB science flight that will investigate the charge composition and energy spectra of primary cosmic rays over the energy range from about 10 10 to 10 14 eV. The instrument is built around a fully active, Bismuth Germanate (BGO) ionization calorimeter to measure the energy deposited by the cascades formed by particles interacting in a thick carbon target. A highly segmented silicon matrix, located above the target, provides good incident charge resolution plus rejection of the "backscattered" particles from the interaction. Trajectory reconstruction is based on the cascade profile in the BGO calorimeter, plus information from the three scintillator hodoscope layers in the target section above it. A full evaluation of the experiment was performed during a test flight occurring between 28 December 2000 and 13 January 2001 where ATIC was carried to an altitude of ~37 km above Antarctica by a ~850,000 m 3 helium filled balloon for one circumnavigation of the continent. All systems behaved well, the detectors performed as expected, >43 Gbytes of engineering and cosmic ray event data was returned and these data are now undergoing preliminary data analysis. During the coming 2002-2003 ATIC science flight we will be attempting two circumnavigations of Antarctica or ~30 days of continuous science data collection in the near-space environment of LDB float altitudes.

The effects of the carrier-envelope phase (CEP) of a few-cycle attosecond pulse on ionized electron momentum and energy spectra are analyzed, both with and without an additional few-cycle IR pulse. In the absence of an IR pulse, the CEP-induced asymmetries in the ionized electron momentum distributions are shown to vary as the 3/2 power of the attosecond pulse intensity. These asymmetries are also found to satisfy an approximate scaling law involving the frequency and intensity of the attosecond pulse. In the presence of even a very weak IR pulse (having an intensity of the order of 10 11 -10 12 W cm -2 ), the attosecond pulse CEP-induced asymmetries in the ionized electron momentum distributions are found to be significantly augmented. In addition, for higher IR laser intensities, we observe for low electron energies peaks separated by the IR photon energy in one electron momentum direction along the laser polarization axis; in the opposite direction, we find structured peaks that are spaced by twice the IR photon energy. Possible physical mechanisms for such asymmetric, low-energy structures in the ionized electron momentum distribution are proposed. Our results are based on singleactive-electron solutions of the three-dimensional, time-dependent Schrödinger equation including atomic potentials appropriate for the H and He atoms.

We measured secondary-electron energy spectra of the H-like ions N +, 0 +, and Ne + (q =3,7,8,9,10) incident on a solid Pt(110) surface at different angles (10' -90') using impact en- ergies of 10q and 15q keV. Clear evidence is found for subsurface electron emission of the KLL Auger electrons. The stepwise Ailing of both K-shell holes of the Ne + projectile is observed in the electron energy spectrum. The dynamics of the filling of the L and K shells in the solid is studied for the Ne + ion. It is found that hollow Ne atoms are formed inside the solid. With decreasing incident charge state of the Ne projectile the LMM Auger lines are shifted to lower energies due to the difFerent screening of the nuclear charge, which is consistent with corresponding Hartree-Fock calculations.

Secondary-electron energy spectra were measured for Ar + (q =9 and 16) and the H-like ions N +, 0 +, and Ne +, incident on solid Cu surfaces at an angle of 10'. The impact energy was varied from 10q to 20q keV. Auger electrons were detected at various observation angles from 20' to 180' with respect to the incident beam. From the Doppler shift of the projectile Auger electrons, the L Auger electrons of argon and neon are found to be emitted from ions whose flight direction is parallel to the incident beam and the K Auger electrons of nitrogen, oxygen, and neon are observed to be emitted from deflected ions. Evidence is provided for incident Ne + and Ar' + that the L shells are incompletely filled when the pro- jectiles reach the surface. The data analysis is supported by model calculations.

We introduce a multistep cascade model for the deexcitation of highly charged ions in the presence of a solid. We apply this model to analyze the yield of the KLL-Auger peak as measured in angular resolved electron energy spectra. The calculation makes use of three probability densities, one for the time distribution of the Auger decay, one for the transport of the ions through the first atomic layers of the target, and the last one for the transport of the electrons from the source to the detector. Each of these probabilities is discussed and modeled. The calculations are compared to measurements of KLL-Auger electrons from low-energy Ne + ions impinging on solid Al. The results support previous estimations that the L-shell sidefeeding of the projectile depends on the incident velocity. For ion energies greater than 1000 eV, the mean path length needed to capture an electron is found to be approximately equal to the next-neighbor distance in the Al lattice. We estimate the yield of KLL electrons emitted from Ne ions with 2, 3,...,8 electrons in the L shell. The mean depth of emission of the KLL electron is determined.

This study investigates the performance of a Phoswich detector in discriminating beta and gamma radiation from the decay of 137 Cs. The detector, combining EJ-204 and EJ-240 scintillators, utilizes their differing scintillation properties for effective signal discrimination. Employing FASTER data acquisition system, experimental calibration was performed using controlled radioactive sources, including 36 Cl and 22 Na. By analyzing the charge integration ratios from fast and slow scintillation components, distinct beta and gamma interactions were identified, allowing calculation of 137 Cs branching ratios. Results were validated through Monte Carlo simulations, enabling further optimization of the Phoswich detector for dual-radiation spectroscopy applications. This work demonstrates the potential of the Phoswich system for precise radiation measurements and advanced spectroscopic analyses.

Seven sets of 2D particle image velocimetry data obtained in the bottom boundary layer of the coastal ocean along the South Carolina and Georgia coast [at the South Atlantic Bight Synoptic Offshore Observational Network (SABSOON) site] are examined, covering the accelerating and decelerating phases of a single tidal cycle at several heights above the seabed. Additional datasets from a previous deployment are also included in the analysis. The mean velocity profiles are logarithmic, and the vertical distribution of Reynolds stresses normalized by the square of the free stream velocity collapse well for data obtained at the same elevation but at different phases of the tidal cycle. The magnitudes of 〈u′u′〉, 〈w′w′〉, and −〈u′w′〉 decrease with height above bottom in the 25–160-cm elevation range and are consistent with the magnitudes and trends observed in laboratory turbulent boundary layers. If a constant stress layer exists, it is located below 25-cm elevation. Two methods for estimat...

PIV measurements performed in the bottom boundary layer of the US Southeastern continental shelf provide seven data sets, each containing 4000 pairs of 2-D vector maps. Each set consisted of two velocity distributions obtained at two magnifications, one with a field of view of 35 ...

The latest results of the first nuclear multifragmentation experiment, E288 [1], at the KEK 12 GeV Proton Synchrotron (KEK-PS) are presented. The energy spectra of intermediate mass fragments (IMFs) were measured inclusively from 30 ° to 150 ° with 20 ° step in the lab. system. Coincidence measurements with one extra IMF emitted toward 90 ° direction in the opposite hemisphere were performed at the same time. Characteristic sideward flow of IMFs toward 70 ° direction was found with the usual isotropic component. This isotropic component was strongly suppressed in the coincidence measurement. These facts may indicate the formation of unusually shaped nuclear matter such as an expanding toroid.

A popular three-dimensional reduction of the Bethe-Salpeter formalism for the description of bound states in quantum field theory is the Salpeter equation, derived by assuming both instantaneous interactions and free propagation of all bound-state constituents. Numerical (variational) studies of the Salpeter equation with confining interaction, however, observed specific instabilities of the solutions, likely related to the Klein paradox and rendering (part of the) bound states unstable. An analytic investigation of the problem by a comprehensive spectral analysis is feasible for the reduced Salpeter equation with only harmonic-oscillator confining interactions. There we are able to prove rigorously that the bound-state solutions correspond to real discrete spectra bounded from below and are thus free of all instabilities.

The spectrum from Compton-scattered x rays is an inherently broad distribution. This distribu- tion is the sum of several Gaussian-like distributions, which gives the sum its unique shape. The Gaussian-like distributions are the result of convoluting the so-called Compton profile, the spread in the scattered-x-ray energies due to the momentum distributions of the target electrons, with the detector response and the geometrical effects. The distribution is then further modified by the ab- sorption within the sample. A formulation for both qualitatively and quantitatively determining the magnitude of the geometrical contributions is presented. This formulation is based on a recently devised approach to the scattering geometry [Hanson, Gigante, Meron, Phys. Rev. Lett. 61, 135 (1988)]. A methodology for determining the geometrical spread in the energy of the scattered x rays is presented. The results can be conveniently used to optimize scattering geometries for the reduc- tion of the geometry-caused spread.

We present data for the 132Xe+56Fe-system at 5.73 MeV/u laboratory energy. Due to inverted kinematics, where Xe is the projectile, we were able to measure energy spectra as well as angular distributions for reaction products with 20_<Z_<60 with unit Z-resolution; i.e. target-and projectile-like fragments have been investigated. The reaction shows a well focussed quasielastic component, where charge transfer from the light to the heavy collision partner dominates. This apparent tendency towards more asymmetric fragmentation is explained by a potential energy surface which favours such charge transfer in order to minimize the asymmetry energy of the liquid drop. The strongly damped component which constitutes the major part of the reaction cross section exhibits characteristics of a fusion-fission reaction with typical fission fragment kinetic energies and 1/sin O .... angular distributions. The maximum cross section is found for the symmetric fragmentation, no clear indication is observed for a diffusion process leading to target-and projectile-like fragments. Our data are difficult to reconcile either with the standard diffusion models or with an equilibrated compound nucleus fission picture. We tentatively conclude that an essential part of the fully damped cross section originates from partial waves for which the compound nucleus has no fission barrier.

The Main Injector Neutrino Oscillation Search (MINOS) experiment uses an acceleratorproduced neutrino beam to perform precision measurements of the neutrino oscillation parameters in the "atmospheric neutrino" sector associated with muon neutrino disappearance. This long-baseline experiment measures neutrino interactions in Fermilab's NuMI neutrino beam with a near detector at Fermilab and again 735 km downstream with a far detector in the Soudan Underground Laboratory in northern Minnesota. The two detectors are magnetized steel-scintillator tracking calorimeters. They are designed to be as similar as possible in order to ensure that differences in detector response have minimal impact on the comparisons of event rates, energy spectra and topologies that are essential to MINOS measurements of oscillation parameters. The design, construction, calibration and performance of the far and near detectors are described in this paper.

We measure a RMI air/SF6 mix induced by a Mach 1.2 shock wave using Schlieren, a constant temperature hot wire anemometer (CTHWA) in IUSTI and a 2 components laser Doppler velocimeter (LDV) at CEA/DIF. The discontinuous interface is materialized by a nitrocellulose ...

Retarding field analyzers (RFAs) provide an effective measure of the local electron cloud density and energy distribution. Proper interpretation of RFA data can yield information about the behavior of the cloud, as well as the surface properties of the instrumented vacuum chamber. However, due to the complex interaction of the cloud with the RFA, particularly in regions of high magnetic field, understanding these measurements can be nontrivial. This paper will examine different methods for interpreting RFA data via cloud simulation programs. Possible techniques include postprocessing the output of a simulation code to predict the RFA response, and incorporating an RFA model into the program itself.

Recently, the Galactic Center has been reported to be a source of very high energy (VHE) γ-rays by the VERITAS, CANGAROO and HESS experiments. The energy spectra as measured by these experiments show substantial differences. In this Letter we present MAGIC observations of the Galactic Center, resulting in the detection of a differential γ-ray flux consistent with a steady, hard-slope power law, described as dN γ /(dAdtdE) = (2.9 ± 0.6) × 10 -12 (E/TeV) -2.2±0.2 cm -2 s -1 TeV -1 . The γ-ray source is centered at (Ra, Dec)=(17 h 45 m 20 s , -29 • 2 ′ ). This result confirms the previous measurements by the HESS experiment and indicates a steady source of TeV γ-rays. We briefly describe the observational technique used, the procedure implemented for the data analysis, and discuss the results in the perspective of different models proposed for the acceleration of the VHE γ-rays.

The paper describes the different methods, used in the MAGIC experiment, to unfold experimental energy distributions of cosmic ray particles (g-rays). Questions and problems related to the unfolding are discussed. Various procedures are proposed which can help to make the unfolding robust and reliable. The different methods and procedures are implemented in the MAGIC software and are used in most of the analyses.

Deuterium Z-pinches are efficient sources of pulsed soft and hard x-rays, fast ions, and neutrons. Many phenomena related to an acceleration of ions and neutron production on the Z-pinches have not yet been explained. Detailed understanding of these phenomena could be multidisciplinary important. Therefore, these phenomena are investigated in joint Czech-Russian experiments on the terawatt class GIT-12 device with the generator output voltage of 600 kV and current at stagnation of about 3 MA. These experiments are interesting since by using the novel experimental load composed of the deuterium gas-puff with outer plasma shell, the neutron yields were significantly increased from the order of 10 to the order of 10. Such relatively high neutron yields were earlier observed on the devices with significantly higher current as the Saturn generator with the pulsed current of about 10 MA. At the same time, in our experiments, hydrogen ions with an energy above 38 MeV were detected. Such re...

Weak scale supersymmetry is often said to be fine-tuned, especially if the matter content is minimal. This is not true if there is a large A term for the top squarks. We present a systematic study on fine-tuning in minimal supersymmetric theories and identify low energy spectra that do not lead to severe fine-tuning. Characteristic features of these spectra are: a large A term for the top squarks, small top squark masses, moderately large tan β, and a small μ parameter. There are classes of theories leading to these features, which are discussed. In one class, which allows a complete elimination of fine-tuning, the Higgsinos are the lightest among all the superpartners of the standard model particles, leading to three nearly degenerate neutralino/chargino states. This gives interesting signals at the LHC -the dilepton invariant mass distribution has a very small endpoint and shows a particular shape determined by the Higgsino nature of the two lightest neutralinos. We demonstrate that these signals are indeed useful in realistic analyses by performing Monte Carlo simulations, including detector simulations and background estimations. We also present a method that allows the determination of all the relevant superparticle masses without using input from particular models, despite the limited kinematical information due to short cascades. This allows us to test various possible models, which is demonstrated in the case of a model with mixed moduli-anomaly mediation. We also give a simple derivation of special renormalization group properties associated with moduli mediated supersymmetry breaking, which are relevant in a model without fine-tuning.

Television has deep impact to the audience, moreover the audience is in the powerless conditions. Indonesia is the real example, that the audience is in the powerless/impowering conditions, on the contrary the television is so power.full. This condition has to be changed, until reach ballance position when the television considers public interest, producing the good quality programs, public appreciates the programs because of the quality and their need, rating of the programs reach high level, and the advertisers interest to these programs. The qouermeni dan Indonesian Broadcast Commission (Komisi Penyiaran Indonesia) must work hard together to realise it.

We consider the possibility that a large fraction of the ultrahigh energy cosmic rays are decay products of Z bosons which were produced in the scattering of ultrahigh energy cosmic neutrinos on cosmological relic neutrinos. We compare the observed ultrahigh energy cosmic ray spectrum with the one predicted in the above Z-burst scenario and determine the required mass of the heaviest relic neutrino as well as the necessary ultrahigh energy cosmic neutrino flux via a maximum likelihood analysis. We show that the value of the neutrino mass obtained in this way is fairly robust against variations in presently unknown quantities, like the amount of neutrino clustering, the universal radio background, and the extragalactic magnetic field, within their anticipated uncertainties. Much stronger systematics arises from different possible assumptions about the diffuse background of ordinary cosmic rays from unresolved astrophysical sources. In the most plausible case that these ordinary cosmic rays are protons of extragalactic origin, one is lead to a required neutrino mass in the range 0.08 eV ≤ mν ≤ 1.3 eV at the 68 % confidence level. This range narrows down considerably if a particular universal radio background is assumed, e.g. to 0.08 eV ≤ mν ≤ 0.40 eV for a large one. The required flux of ultrahigh energy cosmic neutrinos near the resonant energy should be detected in the near future by AMANDA, RICE, and the Pierre Auger Observatory, otherwise the Z-burst scenario will be ruled out.

After a short review of the ultrahigh energy cosmic ray puzzle -the apparent observation of cosmic rays originating from cosmological distances with energies above the expected Greisen-Zatsepin-Kuzmin cutoff 4 × 10 19 eV -we consider strongly interacting neutrino scenarios as an especially interesting solution. We show that all features of the ultrahigh energy cosmic ray spectrum from 10 17 eV to 10 21 eV can be described to originate from a simple power-like injection spectrum of protons, under the assumption that the neutrino-nucleon cross-section is significantly enhanced at center of mass energies above ≈ 100 TeV. In such a scenario, the cosmogenic neutrinos produced during the propagation of protons through the cosmic microwave background initiate air showers in the atmosphere, just as the protons. The total air shower spectrum induced by protons and neutrinos shows excellent agreement with the observations. We shortly discuss TeVscale extensions of the Standard Model which may lead to a realization of a strongly interacting neutrino scenario. We emphasize, however, that such a scenario may even be realized within the standard electroweak model: electroweak instanton/sphaleron induced processes may get strong at ultrahigh energies. Possible tests of strongly interacting neutrino scenarios range from observations at cosmic ray facilities and neutrino telescopes to searches at lepton nucleon scattering experiments.

X-ray free electron lasers (FELs) have been proposed to be constructed both at SLAC in the form of the so-called Linac Coherent Light Source as well as at DESY, where the socalled XFEL laboratory is part of the design of the electron-positron linear collider TESLA. In addition to the immediate applications in condensed matter physics, chemistry, material science, and structural biology, X-ray FELs may be employed also to study some physics issues of fundamental nature. In this context, one may mention the boiling of the vacuum (Schwinger pair creation in an external field), horizon physics (Unruh effect), and axion production. We review these X-ray FEL opportunities of fundamental physics and discuss the necessary technological improvements in order to achieve these goals.

The origin of highest energy cosmic rays is yet unknown. An appealing possibility is the so-called Z-burst scenario, in which a large fraction of these cosmic rays are decay products of Z bosons produced in the scattering of ultrahigh energy neutrinos on cosmological relic neutrinos. The comparison between the observed and predicted spectra constrains the mass of the heaviest neutrino. The required neutrino mass is fairly robust against variations of the presently unknown quantities, such as the amount of relic neutrino clustering, the universal photon radio background and the extragalactic magnetic field. Considering different possibilities for the ordinary cosmic rays the required neutrino masses are determined. In the most plausible case that the ordinary cosmic rays are of extragalactic origin and the universal radio background is strong enough to suppress high energy photons, the required neutrino mass is 0.08 eV ≤ m ν ≤ 0.40 eV . The required ultrahigh energy neutrino flux should be detected in the near future by experiments such as AMANDA, RICE or the Pierre Auger Observatory. *Talk given at Beyond the Desert '02,

We argue that an astrophysical solution to the ultra high energy cosmic ray (UHECR) problem is viable. The detailed study of UHECR energy spectra is performed. The spectral features of extragalactic protons interacting with Cosmic Microwave Background (CMB) are calculated in model-independent way. Using the power-law generation spectrum ∝ E -γg as the only assumption, we analyze four features of the proton spectrum: the GZK cutoff, dip, bump and the second dip. We found the dip, induced by electron-positron production on CMB, as the most robust feature, existing in energy range 1 × 10 18 -4 × 10 19 eV. Its shape is stable relative to various phenomena included in calculations: discreteness of the source distribution, different modes of UHE proton propagation (from rectilinear to diffusive), local overdensity or deficit of the sources, large-scale inhomogeneities in the universe and interaction fluctuations. The dip is well confirmed by observations of AGASA, HiRes, Fly's Eye and Yakutsk detectors. With two free parameters (γg and flux normalization constant) the dip describes about 20 energy bins with χ 2 /d.o.f. ≈ 1 for each experiment. The best fit is reached at γg = 2.7, with the allowed range 2.55 -2.75. The dip is used for energy calibration of the detectors. For each detector independently the energy is shifted by factor λ to reach the minimum χ 2 . We found λAg = 0.9, λHi = 1.2 and λYa = 0.75 for AGASA, HiRes and Yakutsk detectors, respectively. Remarkably, that after this energy shift the fluxes and spectra of all three detectors agree perfectly, with discrepancy between AGASA and HiRes at E > 1 × 10 20 eV being not statistically significant. The excellent agreement of the dip with observations should be considered as confirmation of UHE proton interaction with CMB. The dip has two flattenings. The high energy flattening at E ≈ 1 × 10 19 eV automatically explains ankle, the feature observed in all experiments starting from 1980s. The low-energy flattening at E ≈ 1 × 10 18 eV provides the transition to galactic cosmic rays. This transition is studied quantitatively in this work. Inclusion of primary nuclei with fraction more than 20% upsets the agreement of the dip with observations, which we interpret as an indication to acceleration mechanism. We study in detail the formal problems of spectra calculations: energy losses (the new detailed calculations are presented), analytic method of spectrum calculations and study of fluctuations with help of kinetic equation. The UHECR sources, AGN and GRBs, are studied in a model-dependent way, and acceleration is discussed. Based on the agreement of the dip with existing data, we make the robust prediction for the spectrum at 1 × 10 18 -1 × 10 20 eV to be measured in the nearest future by Auger detector. We also predict the spectral signature of nearby sources, if they are observed by Auger. This paper is long and contains many technical details. For those who are interested only in physical content we recommend to read Introduction and Conclusions, which are written as autonomous parts of the paper.

We present the first constraints on primordial magnetic fields from the Lyman-α forest using full cosmological hydrodynamic simulations. At the scales and redshifts probed by the data, the flux power spectrum is extremely sensitive to the extra power induced by primordial magnetic fields in the linear matter power spectrum, at a scale that we parametrize with kpeak. We rely on a set of more than a quarter million flux models obtained by varying thermal, reionization histories and cosmological parameters. We find a hint of extra power that is well fitted by the PMF model with B∼0.2 nG, corresponding to kpeak∼20 Mpc−1. However, when applying very conservative assumptions on the modelling of the noise, we obtain a 3σ C.L. lower limit kpeak>30 Mpc−1 which translates into the tightest bounds on the strength of primordial intergalactic magnetic fields: B<0.30 nG (for fixed, nearly scale-invariant nB=−2.9).

Using the O(3,2)-symmetric de Sitter solution of Einstein s equation describing a stongly interacting tensor field we show that hadronic bags confining quarks can be represented as de Sitter "microuniverses" with radii given by 1/R = A. x /6. Here v and X are the strong-coupling and the "cosmological" constants which appear in the Einstein equation used. Surprisingly the energy spectrum for the two-body hadronic states is essentially the same as that for a harmonic-oscillator potential, though the wave functions are completely different. The Einstein equation car. be extended to include color for the tensor fields.

We present the results of a statistical study on the proton energy spectra in the range of 35–1600 keV during the one‐hour interval centered on the time of arrival of the shock front at the spacecraft of 75 interplanetary shocks that cover the period from August 1978 until December 1980, using the low‐energy proton experiment on ISEE 3. The strength of the shocks was determined by calculating the ratio of the downstream to upstream plasma density by using the ion data obtained by the Los Alamos solar wind instrument. The shock events were sub‐divided into four different classes based on the behavior of their low‐energy (35–238 keV) spectral index. The signatures of the shock events and their spectral index‐time profiles in the different classes are (1) smooth profiles associated with oblique, strong, and fast shocks, which roughly corresponds with predictions following from diffusive shock acceleration theory; (2) irregular profiles mainly associated with quasi‐perpendicular shocks ...

We present an ab initio approach to solve the time-dependent Schrödinger equation to treat electron and photon impact multiple ionization of atoms or molecules. It combines the already known time scaled coordinate method with a new high order time propagator based on a predictorcorrector scheme. In order to exploit in an optimal way the main advantage of the time scaled coordinate method namely that the scaled wave packet stays confined and evolves smoothly towards a stationary state the modulus square of which being directly proportional to the electron energy spectra in each ionization channel, we show that the scaled bound states should be subtracted from the total scaled wave packet. In addition, our detailed investigations suggest that multi-resolution techniques like for instance, wavelets are the most appropriate ones to represent spatially the scaled wave packet. The approach is illustrated in the case of the interaction of an one-dimensional model atom as well as atomic hydrogen with a strong oscillating field.

D. Adey1, S.K. Agarwalla4, C.M. Ankenbrandt2,1, R. Asfandiyarov5, J.J. Back6, G. Barker6, E. Baussan7, R. Bayes8, S. Bhadra9, V. Blackmore11, A. Blondel5, S.A. Bogacz12, C. Booth10, S.B. Boyd6, A. Bravar5, S.J. Brice1, A.D. Bross1, F. Cadoux5, H. Cease1, A. Cervera13, J. Cobb11, D. Colling14, L. Coney15, A. Dobbs14, J. Dobson14, A. Donini13, P.J. Dornan14, M. Dracos7, F. Dufour5, R. Edgecock30, J. Evans16, M. Geelhoed1, M.A. George14, T. Ghosh13, A. de Gouvêa17, J.J. Gomez-Cadenas13, A. Haesler5, G. Hanson15, P.F. Harrison6, M. Hartz9,18, P. Hernandez13, J.A. Hernando-Morata19, P.J. Hodgson10, P. Huber20, A. Izmaylov13, Y. Karadhzov5, T. Kobilarcik1, J. Kopp21, L. Kormos22, A. Korzenev5, A. Kurup14, Y. Kuno23, P. Kyberd24, J.P. Lagrange25, A.M. Laing13, J. Link20, A. Liu1,3, K.R. Long14, N. McCauley26, K.T. McDonald27, K. Mahn28, C. Martin5, J. Martin18, O. Mena13, S.R. Mishra29, N. Mokhov1, J. Morfin1, Y. Mori25, W. Murray30, D. Neuffer1, R. Nichol31, E. Noah5, M.A. Palmer1, S. Par...

We describe the measurement of the depth of maximum, X max , of the longitudinal development of air showers induced by cosmic rays. Almost 4000 events above 10 18 eV observed by the fluorescence detector of the Pierre Auger Observatory in coincidence with at least one surface detector station are

A Ap system with high statistics and mass resolution was studied in detail. The broad bump in the low mass region can be attributed to contribution from both the impulse and final state interaction mechanisms. The low energy Rp scattering parameters are deduced to be a0 = -2.0+ .5 and r. = 3.0&l. 0 fermi. The higher mass spectrum can be fitted to two Breit-Wigner resonant structures with Ml = 2128.7+. 2, I;= 7.Oi.6, andMa= 2138.82.7, 5 = 9.1k2.4 MeV. Attempts were carried out to understand these peaks via a CN final state interaction model. (Submitted to Phys. Rev. Letters) * Work supported by the U. S. Atomic Energy Commission.

Cette étude concerne le problème de l'interaction entre une couche limite turbulente atmosphérique et un couvert forestier. Les nombreuses études sur le sujet, ont montré que cet écoulement présente plus de similitudes avec une couche de mélange qu'avec un écoulement classique de couche limite. Les simulations numériques 3D (LES), réalisées au dessus d'un couvert forestier homogène, reproduisent correctement les différentes phases de développement de cet écoulement : l'apparition d'une première génération de structures cohérentes résultant du développement d'une instabilité primaire de type Kelvin-Helmholtz, la réorganisation de ces structures par appariement et le développement d'une instabilité secondaire, conduisant à la formation de structures en fer à cheval. L'étude est ensuite généralisée à une configuration hétérogène représentative d'une coupure de combustible ou d'une éclaircie réalisée en bordure ou au coeur d'un massif forestier.

A new mixed model which uses the Leonard expansion (truncated to one term) supplemented by a purely dissipative term (dynamic Smagorinsky) has been devel- oped and tested in actual Large Eddy Simulations (LES) of decaying homogeneous turbulence and of channel flow. This model assumes that the LES lter is smooth in wave space, which is the case of most lters dened in physical space (e.g. ,t op hat, Gaussian, discrete lters). The dynamic procedure has been extended for the mixed model. It is used to determine the model coecient, C, for the added Smagorinsky term. The one-term Leonard model provides signicant local backscatter while re- maining globally dissipative. In ap rioritesting, its correlation with DNS is greater than 0:9. However, when used on its own in actual LES, this model is found to provide too little dissipation. Hence the need for added dissipation, here provided by the dynamic Smagorinsky term. In 643 LES of decaying homogeneous turbu- lence started from Gaussian lter...

W + W -γ production at LEP2 is studied using data collected with the DELPHI detector at centre-of-mass energies between 189 GeV and 209 GeV, corresponding to an integrated luminosity of about 600 pb -1 . Cross-sections are measured for the production of W + W -with a hard, central and isolated photon in the final state, and are found to be compatible with the Standard Model prediction. The photon energy spectra are used to derive limits on anomalous contributions to the W + W -Z 0 γ and W + W -γγ vertices.

First measurements of cross sections for isolated prompt photon production in deep inelastic ep scattering have been made using the ZEUS detector at the HERA electron-proton collider using an integrated luminosity of 121 pb -1 . A signal for isolated photons in the transverse energy and rapidity ranges 5 < E γ T < 10 GeV and -0.7 < η γ < 0.9 was observed for virtualities of the exchanged photon of Q 2 > 35 GeV 2 . Cross sections are presented for inclusive prompt photons and for those accompanied by a single jet in the range E jet T ≥ 6 GeV and -1.5 ≤ η jet < 1.8. Calculations at order α 3 α s describe the data reasonably well.

A comprehensive structural analysis and earthquake-resistant design for a commercial building was undertaken to develop a robust Reinforced Cement Concrete(RCC) frame structure. The project was initiated with a primary focus on designing a multi-level building accommodating complex architectural requirements in a seismically vulnerable zone. Advanced computational techniques were employed using SAP2000 software for structural modeling and analysis. Comprehensive structural components were systematically evaluated including slabs, beams, columns and foundations. Detailed load calculations were performed following IS codes. Structural modeling incorporated multiple levels featuring lower basement. upper basement. lower ground. and five floors with specialized design interventions. Preliminary design calculations were executed for structural elements. Lateral load distributions were analyzed. Load combinations were defined following standard specifications. Reinforcement designs were developed for each structural member. ensuring comprehensive structural safety and performance under various loading conditions.

We have analyzed high time resolution (³6 s) data during the onset and the decay phase of several energetic (³35 keV) ion events observed near the Earth's bow shock by the CCE/AMPTE and IMP-7/8 spacecraft, during times of intense substorm/geomagnetic activity. We found that forward energy dispersion at the onset of events (earlier increase of middle energy ions) and/or a delayed fall of the middle energy ion ¯uxes at the end of events are often evident in high time resolution data. The energy spectra at the onset and the decay of this kind of events show a characteristic hump at middle (50±120 keV) energies and the angular distributions display either anisotropic or broad forms. The time scale of energy dispersion in the ion events examined was found to range from several seconds to $1 h depending on the ion energies compared and on the rate of variation of the Interplanetary Magnetic Field (IMF) direction. Several canditate processes are discussed to explain the observations and it is suggested that a rigidity dependent transport process of magnetospheric particles within the magnetosheath is most probably responsible for the detection of this new type of near bow shock magnetospheric ion events. The new class of ion events was observed within both the magnetosheath and the upstream region.

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