H i 21 cm opacity fluctuations power spectra towards Cassiopeia A

  title={H i 21 cm opacity fluctuations power spectra towards Cassiopeia A},
  author={Nirupam Roy and J. N. Chengalur and Prasun Dutta and Somnath Bharadwaj},
  journal={Monthly Notices of the Royal Astronomical Society: Letters},
The angular power spectrum of H I 21 cm opacity fluctuations is a useful statistic for quantifying the observed opacity fluctuations as well as for comparing these with theoretical models. We present here the H I 21 cm opacity fluctuation power spectrum towards the supernova remnant Cas A from interferometric data with spacial resolution of 5 arcsec and spectral resolution of 0.4 km s −1 . The power spectrum has been estimated using a simple but robust visibility-based technique. We find that… Expand

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