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K Corrections For Type Ia Supernovae and a Test for Spatial Variation of the Hubble Constant

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 نشر من قبل Saul Perlmutter
 تاريخ النشر 1996
  مجال البحث فيزياء
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Cross-filter K corrections for a sample of normal Type Ia supernovae (SNe) have been calculated for a range of epochs. With appropriate filter choices, the combined statistical and systematic K correction dispersion of the full sample lies within 0.05 mag for redshifts z<0.7. This narrow dispersion of the calculated K correction allows the Type Ia to be used as a cosmological probe. We use the K corrections with observations of seven SNe at redshifts 0.3 < z <0.5 to bound the possible difference between the locally measured Hubble constant (H_L) and the true cosmological Hubble constant (H_0).



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