## Structural properties of quotient surfaces of a Hecke group

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- by K. Farooq PDF
- Conform. Geom. Dyn.
**23**(2019), 262-282 Request permission

## Abstract:

We study the properties of the surface $\Sigma _q$, which is a $2q$-fold cover of $\mathbb H/G_q$, where $G_q$ is a Hecke group and $q$ is an integer greater than $3$. We have slightly different situations for the even and odd values of $q$. For odd values of $q$ the surface $\Sigma _q$ is a $\frac {q-1}{2}$ genus surface with a cusp, whereas, for even values it is a $\frac {q-2}{2}$ genus surface with two cusps. We prove that there exist $g$ embedded tori with a hole on $\Sigma _q$, where $g=\frac {q-1}{2}$ when $q$ is an odd integer and $g=\frac {q-2}{2}$ when $q$ is even, with $g$ boundary geodesics at different heights. These boundary geodesics are the separating geodesics intersecting each other transversally. We also prove that the surface $\Sigma _q$ is a hyper-elliptic surface for every integer $q>3$.## References

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## Additional Information

**K. Farooq**- Affiliation: WMI, Univesity of Warwick, Coventry, CV4 7AL, United Kingdom
- Address at time of publication: Department of Sciences and Humanities, National University of Emerging Sciences, FAST, A.K. Brohi Road, H-11/4, Islamabad, Pakistan
- Email: khadija.farooq@nu.edu.pk
- Received by editor(s): September 4, 2014
- Received by editor(s) in revised form: July 26, 2017, and July 13, 2019
- Published electronically: December 3, 2019
- Additional Notes: The author was supported by WPRS grant from the University of Warwick, and HEC Partial Support by the Government of Pakistan
- © Copyright 2019 American Mathematical Society
- Journal: Conform. Geom. Dyn.
**23**(2019), 262-282 - MSC (2010): Primary 20H10, 30B70, 57M50; Secondary 11K60
- DOI: https://doi.org/10.1090/ecgd/341
- MathSciNet review: 4038021