Mathematische Zeitschrift

, 264:1 | Cite as

On newforms for Kohnen plus spaces

  • Masaru Ueda
  • Shunsuke Yamana


In this article, we investigate the plus space of level N, where 4−1 N is a square-free (not necessarily odd) integer. This is a generalization of Kohnen’s work. We define a Hecke isomorphism \({\wp_k}\) of M k+1/2(4M) onto \({M_{k+1/2}^+(8M)}\) for any odd positive integer M. The methods of the proof of the newform theory are this isomorphism, Waldspurger’s theorem, and the dimension identity.


Forms of half-integral weight Newforms Shimura correspondence Kohnen plus space 

Mathematics Subject Classification (2000)



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Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  1. 1.Department of Mathematics, Faculty of ScienceNara Women’s UniversityNaraJapan
  2. 2.Graduate School of MathematicsKyoto UniversityKyotoJapan

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