2,087 research outputs found

    Sensitivity of single and multiple cosmic ray neutrons to the surrounding medium in a lead-free monitor

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    In 1981-1985 the neutron component of cosmic rays was recorded, the effect of cosmic ray multiplication in lead being disregarded. The recording device consisted of neutron counters placed in a polyethylene retarder (polyethylene tubes with wall thickness of 2 cm). The device registered neutrons formed directly on the surface or not deep underground; the intensity of neutrons depended on the chemical composition of the substance. The neutron component was also measured in the Moscow Canal, Belomor-Baltic Canal, and in the Atlantic Ocean. The time variation of 5 minute data of the intensity obtained in the Belomor-Baltic Canal and in the Atlantic Ocean relative to the mean value in the open sea (in %) is presented

    Ultraviolet Radiation from Evolved Stellar Populations: II. The Ultraviolet Upturn Phenomenon in Elliptical Galaxies

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    We present an analysis of the far-ultraviolet upturn phenomenon (UVX) observed in elliptical galaxies and spiral galaxy bulges. Our premise is that the UV radiation from these systems emanates primarily from extreme horizontal branch (EHB) stars and their progeny. We re-derive the broad-band UV colors 1500−V1500-V and 2500−V2500-V for globular clusters and elliptical galaxies from the available satellite data and investigate color-color and color-line strength correlations. We also provide the ingredients necessary for constructing models with arbitrary HB morphologies.Comment: uuencoded compressed postscript file, 60pp. (revisions on pp. 7,8,22,33,37 & 57

    Earth strain measurements with the transportable laser ranging system: Field techniques and planning

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    The potential of the transportable laser ranging system for monitoring the ground deformation around satellite ranging stations and other geodetic control points was examined with emphasis on testing the usefulness of the relative alteration technique. The temporal variation of the ratio of the length of each survey line to the mean length of all survey lines in a given area is directly related to the mean shear strain rate for the area. The data from a series of experimental measurements taken over the Los Angeles basin from a TLRS station at Mt. Wilson show that such ratios can be determined to an accuracy of one part in 10 million with a measurement program lasting for three days and without using any corrections for variations in atmospheric conditions. A numerical experiment using a set of hypothetical data indicates that reasonable estimates of the present shear strain rate and the direction of the principal axes in southern California can be deduced from such measurements over an interval of one to two years

    Examination of Percieved Stress and Coping Mechanisms Among Midwest, Undergraduate, Bachelor of Science Nursing Students

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    Stress is a concept that affects everyone and has been linked to increased incidences of depression and anxiety as well as causing a variety of physical symptoms. College students have been shown to be at an increased risk for higher levels of stress. While studies have been conducted looking at stress levels and causes of stress in undergraduate nursing students in other countries, very few of these studies have been conducted on a population of students within the United States. The purpose of this study was to examine variables that affect levels of stress in undergraduate Bachelor of Science nursing students from an accredited Midwestern nursing college. This study looked at perceived levels of stress in terms of demographic variables, physical and mental symptoms of stress, sources of stress, and coping mechanisms. A questionnaire was developed by combining previously developed surveys on stress. Surveys integrated into the questionnaire included the Life Stress Questionnaire, brief COPE, and Psychological Stress Measure. The instrument measures stress symptoms, perceived levels of stress, sources of stress, and coping mechanisms. The survey was administered to students in three different semester levels within an accredited undergraduate school of nursing school in a Midwestern setting. The results of this study revealed that stress has a significant impact on the lives of nursing students. A statistical significant association of increased age and higher levels of stress was found. School exams were found to be the largest source of stress followed by paperwork, clinical, and not enough money. The group with higher levels of stress reported using the following coping mechanisms to a significant degree: substance abuse, behavioral disengagement, venting, and self-blame. The results of this study are helpful to better understand stress in baccalaureate nursing students. A better understanding of the variables that affect stress levels may help faculty implement interventions to reduce stress. Results may increase student awareness of sources of stress and coping mechanisms that have potential to decrease stress and improve the students’ physical and mental health

    The rotational velocity of the sdOB primary of the eclipsing binary system LB 3459 (AA Dor)

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    We present an analysis of the rotational velocity of the primary of LB 3459 based on 107 new high-resolution and high-S/N ESO VLT UVES spectra. 105 of them cover a complete orbital period (0.26 d) of this binary system. We have determined an orbital period of P = 22600.702 +/- 0.005 sec, a radial velocity amplitude of A_1 = 39.19 +/- 0.05 km/sec, and T_0 = 2451917.152690 +/- 0.000005. From simulations of the He II 4686A line profile (based on NLTE model atmosphere calculations), we derive v_rot = 47 +/- 5 km/sec. We present an animation which shows the orbital movement of the binary system, its synthetic lightcurve, and compares the phase-dependent variation of the predicted with the observed He II 4686A line profile. The radius of the cool component is almost the same size like Jupiter but its mass is about 70 times higher than Jupiter's mass. Thus, from its present mass (M_2 = 0.066 M_sun), the secondary of LB 3459 lies formally within the brown-dwarf mass range (0.013 - 0.08 M_sun). It might be a former planet which has survived the previous common-envelope phase and even has gained mass.Comment: 7 pages, 11 Postscript figures, to appear in A&

    Coupling functions for lead and lead-free neutron monitors from the latitudinal measurements performed in 1982 in the research station Academician Kurchatov

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    The latitudinal behavior of intensities and multiplicities was registered by the neutron monitor 2 NM and the lead-free neutron monitor 3 SND (slow-neuron detector) in the equator-Kaliningrad line in the Atlantic Ocean. Coupling coefficients for 3 SND show the sensitivity of this detector to primary particles of cosmic rays of energies on the average lower than for 2 NM. As multiplicities increase, the coupling coefficients shift towards higher energies

    Long-period cosmic ray variations and their altitude dependence

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    Long-period variations were studied from the data of ground-based cosmic ray (CR) observations. In spite of a large value of an 2-year variation, it is more difficult to obtain its spectrum than the spectrum of a solar diurnal variation. Serious obstacles are caused by changes in individual detectors and in the whole world wide network of CR detectors, by the absence of continuity and uniformity of data series, by various apparatus variations. In discrimination and investigation of long-period variations an important and determining point is preparation and preliminary analysis of data
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