731 research outputs found

    Oral Hisort of Wilena Peterson

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    Transcript of interview with Wilena Peterson.https://scholars.fhsu.edu/ors/1259/thumbnail.jp

    Observational evidence for the origin of X-ray sources in globular clusters

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    Low-mass X-ray binaries, recycled pulsars, cataclysmic variables and magnetically active binaries are observed as X-ray sources in globular clusters. We discuss the classification of these systems, and find that some presumed active binaries are brighter than expected. We discuss a new statistical method to determine from observations how the formation of X-ray sources depends on the number of stellar encounters and/or on the cluster mass. We show that cluster mass is not a proxy for the encounter number, and that optical identifications are essential in proving the presence of primordial binaries among the low-luminosity X-ray sources.Comment: 10 pages, 7 figures, to appear in IAUS 246, Dynamical evolution of dense stellar systems, ed. E. Vesperin

    Ground-water monitoring using polymer optical fibre Bragg gratings

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    Optical fibre Bragg grating sensors inscribed in polymer optical fibre have been shown to be sensitive to the water content of the medium surrounding the fibre and this property has been applied, for example, to the monitoring of humidity and the water content of aviation fuel. In this work we assess the feasibility of using such sensors for monitoring the saturation of soils, which is important for civil engineering applications. We find a very non-linear response, with a rapid increase in Bragg wavelength as the water content increases from 0 to 0.5%, with a much more gradual, but still monotonic, increase thereafter. We speculate on the causes of this response

    Design of ultraprecision machine tools with application to manufacturing of miniature and micro components

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    Currently the underlying necessities for predictability, producibility and productivity remain big issues in ultraprecision machining of miniature/microproducts. The demand on rapid and economic fabrication of miniature/microproducts with complex shapes has also made new challenges for ultraprecision machine tool design. In this paper the design for an ultraprecision machine tool is introduced by describing its key machine elements and machine tool design procedures. The focus is on the review and assessment of the state-of-the-art ultraprecision machining tools. It also illustrates the application promise of miniature/microproducts. The trends on machine tool development, tooling, workpiece material and machining processes are pointed out

    Large-scale structure in the Lyman-alpha forest II: analysis of a group of ten QSOs

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    The spatial distribution of Ly-alpha forest absorption systems towards ten QSOs has been analysed to search for large-scale structure over the redshift range 2.2 < z < 3.4. The QSOs form a closely spaced group on the sky and are concentrated within a 1 deg^2 field. We have employed a technique based on the first and second moments of the transmission probability density function which is capable of identifying and assessing the significance of regions of over- or underdense Ly-alpha absorption. We find evidence for large-scale structure in the distribution of Ly-alpha forest absorption at the > 99 per cent confidence level. In individual spectra we find overdense Ly-alpha absorption on scales of up to 1200 km s^-1. There is also strong evidence for correlated absorption across line of sight pairs separated by < 3 h^-1 proper Mpc (q_0 = 0.5). For larger separations the cross-correlation signal becomes progressively less significant.Comment: 15 pages, LaTeX, 6 Postscript figures, accepted for publication in MNRA

    The Canada-UK Deep Submillimetre Survey - VIII. Source identifications in the 3-hour field

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    We present optical, near-infrared (IR) and radio observations of the 3-hour field of the Canada-UK Deep Submillimetre Survey (CUDSS). Of the 27 submillimetre sources in the field, nine have secure identifications with either a radio source or a near-IR source. We show that the percentage of sources with secure identifications in the CUDSS is consistent with that found for the bright ‘8-mJy' submillimetre survey, once allowance is made for the different submillimetre and radio flux limits. Of the 14 secure identifications in the two CUDSS fields, eight are very red objects (VROs) or extremely red objects (EROs), five have colours typical of normal galaxies and one is a radio source that has not yet been detected at optical/near-IR wavelengths. 11 of the identifications have optical/near-IR structures which are either disturbed or have some peculiarity that suggests that the host galaxy is part of an interacting system. One difference between the CUDSS results and the results from the 8-mJy survey is the large number of low-redshift objects in the CUDSS. We give several arguments why these are genuine low-redshift submillimetre sources rather than being gravitational lenses that are gravitationally amplifying a high-z submillimetre source. We construct a K-z diagram for various classes of high-redshift galaxy and show that the SCUBA galaxies are on average less luminous than classical radio galaxies, but are very similar in both their optical/IR luminosities and their colours to the host galaxies of the radio sources detected in μJy radio survey

    Moyo Vol. III N 1

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    Boyden, John and Rich Vanderklok. Are You a $nob? . 2. Herman, James. River Phoenix: A Final Conversation . 4. Blake, Ben. Arbor Vitae Victories: Other Crafty Everyday Uses For Those Inconspicuous Little Trees . 9. Fischesser, S. Separate But Unequal: A View of Denison\u27s Black Orientation . 10. Gilmore, Seth. Evil Upheaval: The Reforming of Organized Religion... in Granville .; Boyden, John. “Reaching Out & Talking Dirty (When Touching Turns to Touch Tones)”. 20. Vanderklok, Rich. Gen-X Angst . 24. Driscoll, Julie. Bang! Thump (Getting A Taste For The Meat Processing Industry). 25. Stillman, Lisa. The Bare Facts: An Exposé on Public Nudity . 26. Endicott, Josh. Frames . 29. Emmons, Alex. Frames . 29. Emmons, Alex. Untitled. 11. Bussan, Dave. Bull Session With a Former Editor On Denison\u27s Sacred Cow . 30. Webb, Aaron. Color Blind: From Diversity Adversity to Racial Rapport . 33. Archer, Troy Color Blind: From Diversity Adversity to Racial Rapport . 33

    Precise Infrared Radial Velocities from Keck/NIRSPEC and the Search for Young Planets

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    We present a high-precision infrared radial velocity study of late-type stars using spectra obtained with NIRSPEC at the W. M. Keck Observatory. Radial velocity precisions of 50 m/s are achieved for old field mid-M dwarfs using telluric features for precise wavelength calibration. Using this technique, 20 young stars in the {\beta} Pic (age ~12 Myr) and TW Hya (age ~8 Myr) Associations were monitored over several years to search for low mass companions; we also included the chromospherically active field star GJ 873 (EV Lac) in this survey. Based on comparisons with previous optical observations of these young active stars, radial velocity measurements at infrared wavelengths mitigate the radial velocity noise caused by star spots by a factor of ~3. Nevertheless, star spot noise is still the dominant source of measurement error for young stars at 2.3 {\mu}m, and limits the precision to ~77 m/s for the slowest rotating stars (v sin i < 6 km/s), increasing to ~168 m/s for rapidly rotating stars (v sin i > 12 km/s). The observations reveal both GJ 3305 and TWA 23 to be single-lined spectroscopic binaries; in the case of GJ 3305, the motion is likely caused by its 0.09" companion, identified after this survey began. The large amplitude, short-timescale variations of TWA 13A are indicative of a hot Jupiter-like companion, but the available data are insufficient to confirm this. We label it as a candidate radial velocity variable. For the remainder of the sample, these observations exclude the presence of any 'hot' (P < 3 days) companions more massive than 8 MJup, and any 'warm' (P < 30 days) companions more massive than 17 MJup, on average. Assuming an edge-on orbit for the edge-on disk system AU Mic, these observations exclude the presence of any hot Jupiters more massive than 1.8 MJup or warm Jupiters more massive than 3.9 MJup.Comment: Accepted for publication in The Astrophysical Journal. 18 pages, 7 figure

    The Vehicle, Fall 2002

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    Table of Contents Caterpillar DreamsAubrey Bonannopage 4 GrandmotherNatalie Espositopage 5 PhotographNatalie Espositopage 5 For My SisterAnn Hudsonpage 6 BuckeyeCaleb Judypage 6 A Moment\u27s GlowMelissa Knoblockpage 7 April 8,1994Andy Kochpage 8 Koch FuneralsAndy Kochpage 9 Grandpa Koch\u27s Sense of HumorAndy Kochpage 10 DeparturesDave Moutraypage 11 1958 VetteAlex Nicolpage 11 HomelandDave Moutraypage 12 The TravelerDave Moutraypage 12 GrandpaJennifer Probstpage 13 Confusion upon LearningJody Sanchezpage 14 Chucktown PrideMike Scalespage 14 I Might be WrongDallas Schumacherpage 15-20 UntitledAlex Nicholpage 21 Late NightRachel Seftonpage 22 Old DreamsRachel Seftonpage 23 Two-Minded ThoughtsRachel Sefton & Jodi Sanchezpage 24 Strange GraffitiMike Scalespage 24 On PoetryNick Slicerpage 25-26 Sometimes Things Just Happen That WayThomas Webbpage 26-33 Biographiespage 34-35 Editor\u27s Notepage 36https://thekeep.eiu.edu/vehicle/1076/thumbnail.jp
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