870 research outputs found

    The hard X-ray burst spectrometer event listing, 1980 - 1985

    Get PDF
    This event listing is a comprehensive reference for the hard X-ray bursts detected with the Hard X-Ray Burst Spectrometer on the Solar Maximum Mission from the time of launch on February 14, 1980 to September 1985. Over 8000 X-ray events were detected in the energy range from 30 to approx. 500 keV with the vast majority being solar flares. The listing includes the start time, peak time, duration and peak rate of each event

    The hard X-ray burst spectrometer event listing 1980, 1981 and 1982

    Get PDF
    A comprehensive reference for the hard X-ray bursts detected with the Hard X-Ray Burst Spectrometer on the Solar Maximum Mission for the time of launch on February 14, 1980 to March 1983 is provided. Over 6300 X-ray events were detected in the energy range from 30 to approx 500 keV with the vast majority being solar flares. The listing includes the start time, peak time, duration and peak rate of each event

    The complete Hard X Ray Burst Spectrometer event list, 1980-1989

    Get PDF
    This event list is a comprehensive reference for all Hard X ray bursts detected with the Hard X Ray Burst Spectrometer on the Solar Maximum Mission from the time of launch on Feb. 14, 1980 to the end of the mission in Dec. 1989. Some 12,776 events were detected in the energy range 30 to 600 keV with the vast majority being solar flares. This list includes the start time, peak time, duration, and peak rate of each event

    A discrete slug population model determined by egg production

    Get PDF
    Slugs are significant pests in agriculture (as well as a nuisance to gardeners), and it is therefore important to understand their population dynamics for the construction of efficient and effective control measures. Differential equation models of slug populations require the inclusion of large (variable) temporal delays, and strong seasonal forcing results in a non-autonomous system. This renders such models open to only a limited amount of rigorous analysis. In this paper, we derive a novel batch model based purely upon the quantity of eggs produced at different times of the year. This model is open to considerable reduction; from the resulting two variable discrete-time system it is possible to reconstruct the dynamics of the full population across the year and give conditions for extinction or global stability and persistence. Furthermore, the steady state temporal population distribution displays qualitatively different behavior with only small changes in the survival probability of slugs. The model demonstrates how small variations in the favorability of different years may result in widely different slug population fluctuations between consecutive years, and is in good agreement with field data

    Encoded

    Full text link
    ENCODED is an immersive aerial dance performance and installation that uses the latest interactive technologies to build a projected digital environment that responds to the movements of the performers

    The hard X-ray burst spectrometer event listing 1980-1987

    Get PDF
    This event listing is a comprehensive reference for the Hard X-ray bursts detected with the Hard X-ray Burst Spectrometer on the Solar Maximum Mission from the time of launch 14 February 1980 to December 1987. Over 8600 X-ray events were detected in the energy range from 30 to approx. 600 keV with the vast majority being solar flares. The listing includes the start time, peak time, duration and peak rate of each event

    A microfabricated sensor for thin dielectric layers

    Full text link
    We describe a sensor for the measurement of thin dielectric layers capable of operation in a variety of environments. The sensor is obtained by microfabricating a capacitor with interleaved aluminum fingers, exposed to the dielectric to be measured. In particular, the device can measure thin layers of solid frozen from a liquid or gaseous medium. Sensitivity to single atomic layers is achievable in many configurations and, by utilizing fast, high sensitivity capacitance read out in a feedback system onto environmental parameters, coatings of few layers can be dynamically maintained. We discuss the design, read out and calibration of several versions of the device optimized in different ways. We specifically dwell on the case in which atomically thin solid xenon layers are grown and stabilized, in cryogenic conditions, from a liquid xenon bath

    Magnus and Iordanskii Forces in Superfluids

    Full text link
    The total transverse force acting on a quantized vortex in a superfluid is a problem that has eluded a complete understanding for more than three decades. In this letter I propose a remarkably simple argument, somewhat reminiscent of Laughlin's beautiful argument for the quantization of conductance in the quantum Hall effect, to define the superfluid velocity part of the transverse force. This term is found to be ρsκs×vs- \rho_s {\kappa}_s \times {v}_s. Although this result does not seem to be overly controversial, this thermodynamic argument based only on macroscopic properties of the superfluid does offer a robust derivation. A recent publication by Thouless, Ao and Niu has demonstrated that the vortex velocity part of the transverse force in a homogeneous neutral superfluid is given by the usual form ρsκs×vV\rho_s {\kappa}_s \times {v}_V. A combination of these two independent results and the required Galilean invariance yields that there cannot be any transverse force proportional to the normal fluid velocity, in apparent conflict with Iordanskii's theory of the transverse force due to phonon scattering by the vortex.Comment: RevTex, 1 Encapsulated Postscript figur

    A volume inequality for quantum Fisher information and the uncertainty principle

    Full text link
    Let A1,...,ANA_1,...,A_N be complex self-adjoint matrices and let ρ\rho be a density matrix. The Robertson uncertainty principle det(Covρ(Ah,Aj))det(i2Tr(ρ[Ah,Aj])) det(Cov_\rho(A_h,A_j)) \geq det(- \frac{i}{2} Tr(\rho [A_h,A_j])) gives a bound for the quantum generalized covariance in terms of the commutators [Ah,Aj][A_h,A_j]. The right side matrix is antisymmetric and therefore the bound is trivial (equal to zero) in the odd case N=2m+1N=2m+1. Let ff be an arbitrary normalized symmetric operator monotone function and let ρ,f_{\rho,f} be the associated quantum Fisher information. In this paper we conjecture the inequality det(Covρ(Ah,Aj))det(f(0)2ρ,f) det (Cov_\rho(A_h,A_j)) \geq det (\frac{f(0)}{2} _{\rho,f}) that gives a non-trivial bound for any natural number NN using the commutators i[ρ,Ah]i[\rho, A_h]. The inequality has been proved in the cases N=1,2N=1,2 by the joint efforts of many authors. In this paper we prove the case N=3 for real matrices
    corecore