Pioneer 10 and Voyager observations of the interstellar medium in scattered emission of the He584 A and H Lya 1216 A lines

The combination of Pioneer photometric and Voyager spectrometric observations of EUV interstellar-interplanetary emissions in the region beyond 5 A was applied to a determination of atomic hydrogen and helium densities. These density estimates obtained from direct measurement of scattered radiation depend on absolute calibration of the instruments in the same way as other earlier determinations based on the same method. However, the spacecraft data were combined with daily full sun averages of the H Lyman 1216 A line obtained by the Solar Mesospheric Explorer satellite to obtain a measure of atomic hydrogen density independent of instrument absolute calibration. The method depends on observations of long and short term temporal variability of the solar line over a one year period, and the fact that the ISM is optically thick. The density estimates from preliminary work on these observations are H = 0.12 cu cm and H = .016 cu cm, giving a density ratio close to the cosmic abundance value in contrast to some earlier results indicating a depletion of atomic hydrogen. Estimates were obtained of galactic background emissions in the signals of both spacecraft

Development of electrical test procedures for qualification of spacecraft against EID. Volume 1: The CAN test and other relevant data

A combined experimental and analytical program to develop system electrical test procedures for the qualification of spacecraft against damage produced by space-electron-induced discharges (EID) occurring on spacecraft dielectric outer surfaces is described. The data on the response of a simple satellite model, called CAN, to electron-induced discharges is presented. The experimental results were compared to predicted behavior and to the response of the CAN to electrical injection techniques simulating blowoff and arc discharges. Also included is a review of significant results from other ground tests and the P78-2 program to form a data base from which is specified those test procedures which optimally simulate the response of spacecraft to EID. The electrical and electron spraying test data were evaluated to provide a first-cut determination of the best methods for performance of electrical excitation qualification tests from the point of view of simulation fidelity

From Forbidden Coronal Lines to Meaningful Coronal Magnetic Fields

We review methods to measure magnetic fields within the corona using the polarized light in magnetic-dipole (M1) lines. We are particularly interested in both the global magnetic-field evolution over a solar cycle, and the local storage of magnetic free energy within coronal plasmas. We address commonly held skepticisms concerning angular ambiguities and line-of-sight confusion. We argue that ambiguities are in principle no worse than more familiar remotely sensed photospheric vector-fields, and that the diagnosis of M1 line data would benefit from simultaneous observations of EUV lines. Based on calculations and data from eclipses, we discuss the most promising lines and different approaches that might be used. We point to the S-like [Fe {\sc XI}] line (J=2 to J=1) at 789.2nm as a prime target line (for ATST for example) to augment the hotter 1074.7 and 1079.8 nm Si-like lines of [Fe {\sc XIII}] currently observed by the Coronal Multi-channel Polarimeter (CoMP). Significant breakthroughs will be made possible with the new generation of coronagraphs, in three distinct ways: (i) through single point inversions (which encompasses also the analysis of MHD wave modes), (ii) using direct comparisons of synthetic MHD or force-free models with polarization data, and (iii) using tomographic techniques.Comment: Accepted by Solar Physics, April 201

INTRAMUSCULAR COLLAGEN AND SERUM HYDROXYPROLINE AS RELATED TO IMPLANTED TESTOSTERONE, DIHYDROTESTOSTERONE AND ESTRADIOL-17β IN GROWING WETHERS

Relationships of implanted testosterone, dihydrotestosterone and estradiol-17β to collagen degradation and intramuscular collagen concentration and stability were determined. Intramuscular collagen content, solubility and shrinkage temperature and serum hydroxyproline were analyzed in groups of six rams, wethers, and wethers implanted with various levels of testosterone or dihydrotestosterone (Exp. 1) and groups of 10 rams, wethers and wethers implanted with estradiol-17β, dihydrotestosterone or a combination of these two steroids (Exp. 2). Intramuscular collagen content in both experiments was higher (P \u3c .05) in muscles of rams than in muscles of wethers. Administration of the highest level of testosterone to wethers raised (P \u3c .05) total and insoluble intramuscular collagen to concentrations noted in rams. Administration of the testosterone metabolite, dihydrotestosterone, to wethers had no effect on intramuscular collagen. Administration of estradiol-17β to wethers tended to raise concentrations of intramuscular collagen so that they were no longer lower (P \u3c .05) than those in rams. Collagen stability as measured by solubility and thermal shrinkage temperature did not differ among rams, wethers or implanted wethers (P \u3e .05). Increases in collagen accretion due to hormone administration were observed to be the result of increases in the insoluble portion of the intramuscular collagen (P \u3c .05)

INTRAMUSCULAR COLLAGEN AND SERUM HYDROXYPROLINE AS RELATED TO IMPLANTED TESTOSTERONE, DIHYDROTESTOSTERONE AND ESTRADIOL-17β IN GROWING WETHERS

Relationships of implanted testosterone, dihydrotestosterone and estradiol-17β to collagen degradation and intramuscular collagen concentration and stability were determined. Intramuscular collagen content, solubility and shrinkage temperature and serum hydroxyproline were analyzed in groups of six rams, wethers, and wethers implanted with various levels of testosterone or dihydrotestosterone (Exp. 1) and groups of 10 rams, wethers and wethers implanted with estradiol-17β, dihydrotestosterone or a combination of these two steroids (Exp. 2). Intramuscular collagen content in both experiments was higher (P \u3c .05) in muscles of rams than in muscles of wethers. Administration of the highest level of testosterone to wethers raised (P \u3c .05) total and insoluble intramuscular collagen to concentrations noted in rams. Administration of the testosterone metabolite, dihydrotestosterone, to wethers had no effect on intramuscular collagen. Administration of estradiol-17β to wethers tended to raise concentrations of intramuscular collagen so that they were no longer lower (P \u3c .05) than those in rams. Collagen stability as measured by solubility and thermal shrinkage temperature did not differ among rams, wethers or implanted wethers (P \u3e .05). Increases in collagen accretion due to hormone administration were observed to be the result of increases in the insoluble portion of the intramuscular collagen (P \u3c .05)

Interpretation of Pioneer 10 heliospheric Ly ? glow data obtained beyond 30 AU

International audienceThe Pioneer 10 (P10) Ly ? dataset is the only dataset that is available for the study of the very local interstellar medium (VLISM) in the downstream direction relative to the incoming interstellar neutral hydrogen flow, at very large distances from the sun. Selected P10 data obtained in 1984 and 1986 at distances between 31.81 to 32.25 and 37.29 to 37.74 AU have been used to estimate the local interstellar neutral hydrogen and proton densities. State of the art, stationary neutral-plasma and radiative transfer models have been used in the interpretation of the data. No stationary VLISM heliospheric model was found that best fitted both the P10 1984 data and the 1986 data. The failure to find a single best fit model is most probably due to the fact that the heliospheric model used here did not incorporate time-dependence and interstellar magnetic field effects

Spectral simplicity and asymptotic separation of variables

We describe a method for comparing the real analytic eigenbranches of two families of quadratic forms that degenerate as t tends to zero. One of the families is assumed to be amenable to `separation of variables' and the other one not. With certain additional assumptions, we show that if the families are asymptotic at first order as t tends to 0, then the generic spectral simplicity of the separable family implies that the eigenbranches of the second family are also generically one-dimensional. As an application, we prove that for the generic triangle (simplex) in Euclidean space (constant curvature space form) each eigenspace of the Laplacian is one-dimensional. We also show that for all but countably many t, the geodesic triangle in the hyperbolic plane with interior angles 0, t, and t, has simple spectrum.Comment: 53 pages, 2 figure

EUV-VUV Photolysis of Molecular Ice Systems of Astronomical Interest

We wish to report laboratory simulation results obtained from extreme ultraviolet (EUV) and vacuum ultraviolet (VUV) photolysis of molecular ices relevant to the cometary-type ices and icy satellites of planetary systems. Specifically, we identify the type of molecules that form in the ices and/or those that come off the ice surfaces, quantify their production yields and destruction yields, understand their production mechanisms, and ascertain their significance in astronomical environments

On the magnetic structure of the solar transition region

We examine the hypothesis that ``cool loops'' dominate emission from solar transition region plasma below temperatures of $2\times10^5$K. We compare published VAULT images of H L$\alpha$, a lower transition region line, with near-contemporaneous magnetograms from Kitt Peak, obtained during the second flight (VAULT-2) on 14 June 2002. The measured surface fields and potential extrapolations suggest that there are too few short loops, and that L$\alpha$ emission is associated with the base regions of longer, coronal loops. VAULT-2 data of network boundaries have an asymmetry on scales larger than supergranules, also indicating an association with long loops. We complement the Kitt Peak data with very sensitive vector polarimetric data from the Spectro-Polarimeter on board Hinode, to determine the influence of very small magnetic concentrations on our analysis. From these data two classes of behavior are found: within the cores of strong magnetic flux concentrations ($> 5\times10^{18}$ Mx) associated with active network and plage, small-scale mixed fields are absent and any short loops can connect just the peripheries of the flux to cell interiors. Core fields return to the surface via longer, most likely coronal, loops. In weaker concentrations, short loops can connect between concentrations and produce mixed fields within network boundaries as suggested by Dowdy and colleagues. The VAULT-2 data which we examined are associated with strong concentrations. We conclude that the cool loop model applies only to a small fraction of the VAULT-2 emission, but we cannot discount a significant role for cool loops in quieter regions. We suggest a physical picture for how network L$\alpha$ emission may occur through the cross-field diffusion of neutral atoms from chromospheric into coronal plasma.Comment: Accepted by ApJ, 9 May 200