4,188 research outputs found

    Methods of Communicating with and Relating to the Parents of Migrant Children

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    It is the purpose of this study to (1) determine the present status of efforts, techniques, and materials used by school personnel to communicate with parents of migrant and culturally deprived or disadvantaged children, and (2) identify ways and methods of improving the presently used efforts, techniques, and materials

    Direct Evidence for the Source of Reported Magnetic Behavior in "CoTe"

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    In order to unambiguously identify the source of magnetism reported in recent studies of the Co-Te system, two sets of high-quality, epitaxial CoTex_x films (thickness ≃\simeq 300 nm) were prepared by pulse laser deposition (PLD). X-ray diffraction (XRD) shows that all of the films are epitaxial along the [001] direction and have the hexagonal NiAs structure. There is no indication of any second phase metallic Co peaks (either fccfcc or hcphcp) in the XRD patterns. The two sets of CoTex_x films were grown on various substrates with PLD targets having Co:Te in the atomic ratio of 50:50 and 35:65. From the measured lattice parameters c=5.396A˚c = 5.396 \AA for the former and c=5.402A˚c = 5.402\AA for the latter, the compositions CoTe1.71_{1.71} (63.1% Te) and CoTe1.76_{1.76} (63.8% Te), respectively, are assigned to the principal phase. Although XRD shows no trace of metallic Co second phase, the magnetic measurements do show a ferromagnetic contribution for both sets of films with the saturation magnetization values for the CoTe1.71_{1.71} films being approximately four times the values for the CoTe1.76_{1.76} films. 59^{59}Co spin-echo nuclear magnetic resonance (NMR) clearly shows the existence of metallic Co inclusions in the films. The source of weak ferromagnetism reported in several recent studies is due to the presence of metallic Co, since the stoichiometric composition "CoTe" does not exist.Comment: 19 pages, 7 figure

    Young stars and dust in AFGL437: NICMOS/HST polarimetric imaging of an outflow source

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    We present near infrared broad band and polarimetric images of the compact star forming cluster AFGL437 obtained with the NICMOS instrument aboard HST. Our high resolution images reveal a well collimated bipolar reflection nebulosity in the cluster and allow us to identify WK34 as the illuminating source. The scattered light in the bipolar nebulosity centered on this source is very highly polarized (up to 79%). Such high levels of polarization implies a distribution of dust grains lacking large grains, contrary to the usual dust models of dark clouds. We discuss the geometry of the dust distribution giving rise to the bipolar reflection nebulosity and make mass estimates for the underlying scattering material. We find that the most likely inclination of the bipolar nebulosity, south lobe inclined towards Earth, is consistent with the inclination of the large scale CO molecular outflow associated with the cluster, strengthening the identification of WK34 as the source powering it.Comment: 26 pages, 10 figues. Accepted for publication in the Astrophysical Journa

    Are There Any Type 2 QSOs? The Case of AXJ0341.4-4453

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    The X-ray source AXJ0341.4-4453 was described by Boyle et al. as a Type 2 AGN at z = 0.672 based on the absence of broad emission lines in the observed wavelength range 4000-7000 Angstroms. We obtained a new spectrum of AXJ0341.4-4453 extending to 9600 Angstroms which reveals broad Balmer lines and other characteristics of Seyfert 1 galaxies. The FWHM of broad H-beta is at least 1600 km/s, while [O III]5007 has FWHM = 730 km/s. The flux ratio [O III]5007/H-beta = 1. Thus, AXJ0341.4-4453 is by definition a narrow-line Seyfert 1 galaxy, or perhaps a moderately reddened Seyfert 1 galaxy, but it is not a Type 2 QSO. Although examples of the latter have long been sought, particularly in connection with the problem of the X-ray background, there is still virtually no evidence for the existence of any Type 2 QSO among X-ray selected samples.Comment: 4 pages, 3 figures, to appear in MNRA
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