wsclean: an implementation of a fast, generic wide-field imager for radio astronomy

  title={wsclean: an implementation of a fast, generic wide-field imager for radio astronomy},
  author={Andr{\'e} R. Offringa and Benjamin McKinley and Natasha Hurley-Walker and Frank H. Briggs and Randall B. Wayth and David L. Kaplan and Martin E. Bell and L. L. Feng and Abraham R. Neben and J. D. Hughes and Jonghwan Rhee and Tara Murphy and N. D. Ramesh Bhat and Gianni Bernardi and Judd D. Bowman and Roger J. Cappallo and Brian E. Corey and Avinash A. Deshpande and David Emrich and Aaron Ewall-Wice and Bryan M. Gaensler and Robert F. Goeke and Lincoln J. Greenhill and Bryna J. Hazelton and Luke Hindson and Melanie Johnston-Hollitt and Daniel C. Jacobs and Justin C. Kasper and Eric Kratzenberg and Emil Lenc and Colin J. Lonsdale and Mervyn J. Lynch and Stephen R. McWhirter and Daniel A. Mitchell and Miguel F. Morales and Edward T. Morgan and N A Kudryavtseva and Divya Oberoi and Stephen M. Ord and Bart Pindor and Pietro Procopio and Thiagaraj Prabu and Jennifer Riding and D. Anish Roshi and N. Udaya Shankar and K. S. Srivani and Ravi Subrahmanyan and Steven J. Tingay and Mark F. Waterson and R. L. Webster and Alan R. Whitney and A. Williams and C. L. Williams},
  journal={Monthly Notices of the Royal Astronomical Society},
Astronomical widefield imaging of interferometric radio data is computationally expensive, especially for the large data volumes created by modern non-coplanar many-element arrays. We present a new widefield interferometric imager that uses the w-stacking algorithm and can make use of the w-snapshot algorithm. The performance dependencies of CASA's w-projection and our new imager are analysed and analytical functions are derived that describe the required computing cost for both imagers. On… 

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