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141.
A. D. Biggs D. Rusin I. W. A. Browne A. G. de Bruyn N. J. Jackson L. V. E. Koopmans J. P. McKean S. T. Myers R. D. Blandford K.-H. Chae C. D. Fassnacht M. A. Norbury T. J. Pearson P. M. Phillips A. C. S. Readhead P. N. Wilkinson 《Monthly notices of the Royal Astronomical Society》2003,338(4):1084-1088
142.
Rodger I. Thompson 《Astrophysics and Space Science》2003,284(2):353-356
Tests and constraints on current theories of galaxy formation and evolution are presented. They are derived from observations
of the Northern Hubble Deep Field with WFPC2 and NICMOS. Photometric redshifts, extinctions and spectral energy distributions
are calculated for all objects in the field. The tests and constraints are derived from the output of this analysis. The tests
of the predictions from hierarchical and pure luminosity evolution galaxy evolution calculations favor the hierarchical model.
Constraints are provided by the current luminosity function and its evolution to a redshift of 6.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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A flare of OH maser emission was discovered in W75N in 2000. Its location was determined with the Very Long Baseline Array (VLBA) to be within 110 au from one of the ultracompact H ii regions, Very Large Array 2 (VLA2). The flare consisted of several maser spots. Four of the spots were found to form Zeeman pairs, all of them with a magnetic field strength of about 40 mG. This is the highest ever magnetic field strength found in OH masers, an order of magnitude higher than in typical OH masers. Three possible sources for the enhanced magnetic field are discussed: (i) the magnetic field of the exciting star dragged out by the stellar wind; (ii) the general interstellar field in the gas compressed by the magnetohydrodynamic shock; and (iii) the magnetic field of planets which orbit the exciting star and produce maser emission in gaseous envelopes. 相似文献
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149.
Churyumov K. I. Klesachonok V. V. Mussaev F. A. Bikmaev I. F. Galazutdinov G. H. 《Earth, Moon, and Planets》1997,78(1-3):105-110
We present the results of the preliminary study of the comet Hale-Bopp spectrum obtained April 17, 1997 by K. Churyumov and F. Mussayev with the help of the 1-meter Zeiss reflector and the echelle spectrometer (spectral resolutionλ/Δ λ ≈ 50000), CCD and the long slit, oriented along the radius-vector(“Sun-comet direction”). Energy distributions for three selected regions including the C3, C2 (0-0) and CN(Δ ν = 0) molecules emissions of the comet Hale-Bopp spectrum were built. The rotational lines of the CN(Δ ν = 0) band were identified. The nature of the high emission peak near λ 4020 Å in the C3 band is discussed. The presence of the cometary continuum of the nonsolar origin is assumed. 相似文献
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