1,484 research outputs found

    SEGUE: A Spectroscopic Survey of 240,000 Stars with g = 14-20

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    The Sloan Extension for Galactic Understanding and Exploration (SEGUE) Survey obtained ≈240,000 moderateresolution (R ~ 1800) spectra from 3900 Å to 9000 Å of fainter Milky Way stars (14.0 < g < 20.3) of a wide variety of spectral types, both main-sequence and evolved objects, with the goal of studying the kinematics and populations of our Galaxy and its halo. The spectra are clustered in 212 regions spaced over three quarters of the sky. Radial velocity accuracies for stars are σ(RV) ~ 4 km s^(−1) at g < 18, degrading to σ(RV) ~ 15 km s^(−1) at g ~ 20. For stars with signal-to-noise ratio >10 per resolution element, stellar atmospheric parameters are estimated, including metallicity, surface gravity, and effective temperature. SEGUE obtained 3500 deg^2 of additional ugriz imaging (primarily at low Galactic latitudes) providing precise multicolor photometry (σ(g, r, i) ~ 2%), (σ(u, z) ~ 3%) and astrometry (≈0".1) for spectroscopic target selection. The stellar spectra, imaging data, and derived parameter catalogs for this survey are publicly available as part of Sloan Digital Sky Survey Data Release 7

    Milky Way Tomography with K and M Dwarf Stars: the Vertical Structure of the Galactic Disk

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    We use the number density distributions of K and M dwarf stars with vertical height from the Galactic disk, determined using observations from the Sloan Digital Sky Survey, to probe the structure of the Milky Way disk across the survey's footprint. Using photometric parallax as a distance estimator we analyze a sample of several million disk stars in matching footprints above and below the Galactic plane, and we determine the location and extent of vertical asymmetries in the number counts in a variety of thin- and thick-disk subsamples in regions of some 200 square degrees within 2 kpc in vertical distance from the Galactic disk. These disk asymmetries present wave-like features as previously observed on other scales and at other distances from the Sun. We additionally explore the scale height of the disk and the implied offset of the Sun from the Galactic plane at different locations, noting that the scale height of the disk can differ significantly when measured using stars only above or only below the plane. Moreover, we compare the shape of the number density distribution in the north for different latitude ranges with a fixed range in longitude and find the shape to be sensitive to the selected latitude window. We explain why this may be indicative of a change in stellar populations in the latitude regions compared, possibly allowing access to the systematic metallicity difference between thin- and thick-disk populations through photometry.Comment: 41 pages, 17 figures, accepted for publication in ApJ; published version [oversight in Fig. 12 fixed

    The Orbit of the Orphan Stream

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    We use recent SEGUE spectroscopy and SDSS and SEGUE imaging data to measure the sky position, distance, and radial velocities of stars in the tidal debris stream that is commonly referred to as the "Orphan Stream." We fit orbital parameters to the data, and find a prograde orbit with an apogalacticon, perigalacticon, and eccentricity of 90 kpc, 16.4 kpc and 0.7, respectively. Neither the dwarf galaxy UMa II nor the Complex A gas cloud have velocities consistent with a kinematic association with the Orphan Stream. It is possible that Segue-1 is associated with the Orphan Stream, but no other known Galactic clusters or dwarf galaxies in the Milky Way lie along its orbit. The detected portion of the stream ranges from 19 to 47 kpc from the Sun and is an indicator of the mass interior to these distances. There is a marked increase in the density of Orphan Stream stars near (l,b)=(253,49) deg., which could indicate the presence of the progenitor at the edge of the SDSS data. If this is the progenitor, then the detected portion of the Orphan Stream is a leading tidal tail. We find blue horizontal branch (BHB) stars and F turnoff stars associated with the Orphan Stream. The turnoff color is (g-r)_0=0.22. The BHB stars have a low metallicity of [Fe/H]=-2.1. The orbit is best fit to a halo potential with a halo plus disk mass of about 2.6x10^11 Solar masses, integrated to 60 kpc from the Galactic center. Our best fit is found with a logarithmic halo speed of v_halo=73+/-24 km/s, a disk+bulge mass of M(R< 60 kpc) = 1.3x10^11 Solar masses, and a halo mass of M(R< 60 kpc) = 1.4x10^11 Solar masses. The Orphan Stream is projected to extend to 90 kpc from the Galactic center, and measurements of these distant parts of the stream would be a powerful probe of the mass of the Milky Way (truncated).Comment: 17 Figures, ApJ accepte

    DAMPAK PERNIKAHAN USIA DINI TERHADAP KEHARMONISAN DALAM KELUARGA(SUATU STUDI DI KECAMATAN SEUNAGAN KABUPATEN NAGAN RAYA)

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    ABSTRAKPernikahan usia dini adalah pernikahan di bawah usia yang seharusnya belum siap untuk melaksanakan pernikahan. Untuk menikah ada 2 hal yang perlu diperhatikan yaitu kesiapan fisik dan kesiapan mental. Kesiapan fisik seseorang dilihat dari faktor ekonomi, sedangkan kesiapan mental dilihat dari faktor usia. Akan timbul permasalahan jika pernikahan dilakukan di usia yang sangat muda yaitu menikah dini yang secara fisik dan mental memang belum siap. Pernikahan dini cenderung terjadi dalam kehidupan masyarakat desa yang telah berlangsung sejak dulu dan masih bertahan sampai sekarang. Bagi masyarakat sekarang pernikahan usia dini terjadi karena faktor ekonomi semata, faktor keinginan sendiri dan keinginan orang tua (terpaksa). Faktor ini yang banyak terjadi di Kecamatan Seunagan Kabupaten Nagan Raya. Penelitian menggunakan teori Fungsionalisme Struktural yang dikembangkan oleh A.R. Radcliffe-Brown yang mengemukakan bahwa berbagai aspek perilaku sosial, bukanlah berkembang untuk memuaskan kebutuhan individual, tapi justru timbul untuk mempertahankan struktur sosial masyarakat. Penelitian ini dilakukan di Kecamatan Seunagan Kabupaten Nagan Raya. Metode yang digunakan dalam penelitian ini adalah kualitatif deskriptif. Jenis penelitian yang di lakukan adalah penelitian lapangan(field research) yaitu penelitian langsung yang dilakukan di Kecamatan Seunagan Kabupaten Nagan Raya. Data yang didapatkan penulis diperoleh dari observasi, dokumentasi dan wawancara. Hasil penelitian menemukan bahwa penyebabnya karena faktor ekonomi, keinginan diri sendiri dan keinginan orang tua. Harmonisnya suatu keluarga tidak mesti menikah di usia matang, tapi usia dini keluarganya banyak juga yang harmonis. Dampak dari pernikahan dini tidak hanya memiliki dampak negatif tetapi juga dampak positif yakni; menambah ilmu pengalaman hidup rumah tangga dan menimbulkan rasa tanggung jawab.Kata Kunci: Penyebab, Keharmonisan, Dampak dan Pernikahan Usia Dini

    Hubungan Kepatuhan Pasien Gagal Ginjal Kronik Dengan Keteraturan Tindakan Haemodialisa Di Blu Rsup Prof Dr. R.d Kandou Manado

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    Prevalance of population chronic renal failurein the North Celebes be in the second position of national that is 0,4%. Obedience of the chronic renal failure patient based on the survey on the February 2014 on going haemodialysis treatmen as much as 167 patients, as amount 38,9% don\u27t followed haemodilysis treatment.Purpose of the research is to knowing relationship between obedience of patient chronic renal failure with haemodialysis treatment as regularly in BLU RSUP Prof. Dr. R.D. Kandou Manado. Type of this research is analytic descriptive with cross sectional approach designs. Population and sample as amount as 64 respondens in Dahlia rooms. Result of the research as following, as much as (98%) respondens obey and regularly, (2%) respondens obey and not regularly, (50%) respondens not obey and obey, and (50%) respondens not obey and not regularly. Result of the Chi Square test showed that there were signidicantly relationship between obedience chronic renal failure patient with haemodialysis treatment as regularly pvalue=0,000&lt;p0,05.Conclusion that obedience chronic renal failure patient significantly relationship with haemodialysis treatment as regularly. Suggestion, hoping to continuously research, so that can be development this research with searching for the other factors had be done, so can met describing as overall about obedience of the ongoing haemodialysis treatment patient

    Teaching Communicative Translation Through Skopos Theory

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    Communication is considered successful when the people involved understand each others. Since there are many languages around their world, languages can also be a barrier in communicating. People with a particular language cannot interact with other who has different language than his to link this shortage, it requires the role of a translator. Nowadays many people are just taking the opportunity to be translators just because they are bilingual without any awareness of what it is called as successful in translation People with a particular language cannot interact with other who has different language than his. In this regard, this paper will discuss what aspect are necessary to be a professional translator. This understanding will lead us to know how to teach translation to students in order to achieve a communicative translation

    Teaching Communicative Translation through Skopos Theory

    Get PDF
    Communication is considered successful when the people involved understand each others. Since there are many languages around their world, languages can also be a barrier in communicating. People with a particular language cannot interact with other who has different language than his to link this shortage, it requires the role of a translator. Nowadays many people are just taking the opportunity to be translators just because they are bilingual without any awareness of what it is called as successful in translation People with a particular language cannot interact with other who has different language than his. In this regard, this paper will discuss what aspect are necessary to be a professional translator. This understanding will lead us to know how to teach translation to students in order to achieve a communicative translation

    Mapping the stellar structure of the Milky Way thick disk and halo using SEGUE photometry

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    We map the stellar structure of the Galactic thick disk and halo by applying color-magnitude diagram (CMD) fitting to photometric data from the SEGUE survey, allowing, for the first time, a comprehensive analysis of their structure at both high and low latitudes using uniform SDSS photometry. Incorporating photometry of all relevant stars simultaneously, CMD fitting bypasses the need to choose single tracer populations. Using old stellar populations of differing metallicities as templates we obtain a sparse 3D map of the stellar mass distribution at |Z|>1 kpc. Fitting a smooth Milky Way model comprising exponential thin and thick disks and an axisymmetric power-law halo allows us to constrain the structural parameters of the thick disk and halo. The thick-disk scale height and length are well constrained at 0.75+-0.07 kpc and 4.1+-0.4 kpc, respectively. We find a stellar halo flattening within ~25 kpc of c/a=0.88+-0.03 and a power-law index of 2.75+-0.07 (for 7<R_{GC}<~30 kpc). The model fits yield thick-disk and stellar halo densities at the solar location of rho_{thick,sun}=10^{-2.3+-0.1} M_sun pc^{-3} and rho_{halo,sun}=10^{-4.20+-0.05} M_sun pc^{-3}, averaging over any substructures. Our analysis provides the first clear in situ evidence for a radial metallicity gradient in the Milky Way's stellar halo: within R<~15 kpc the stellar halo has a mean metallicity of [Fe/H]=-1.6, which shifts to [Fe/H]=-2.2 at larger radii. Subtraction of the best-fit smooth and symmetric model from the overall density maps reveals a wealth of substructures at all latitudes, some attributable to known streams and overdensities, and some new. A simple warp cannot account for the low latitude substructure, as overdensities occur simultaneously above and below the Galactic plane. (abridged)Comment: 13 pages, 10 figures, accepted for publication in Astrophysical Journa
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