Invariants
Level: | $40$ | $\SL_2$-level: | $40$ | Newform level: | $1600$ | ||
Index: | $480$ | $\PSL_2$-index: | $240$ | ||||
Genus: | $13 = 1 + \frac{ 240 }{12} - \frac{ 0 }{4} - \frac{ 0 }{3} - \frac{ 16 }{2}$ | ||||||
Cusps: | $16$ (none of which are rational) | Cusp widths | $5^{8}\cdot10^{4}\cdot40^{4}$ | Cusp orbits | $4^{2}\cdot8$ | ||
Elliptic points: | $0$ of order $2$ and $0$ of order $3$ | ||||||
Analytic rank: | $6$ | ||||||
$\Q$-gonality: | $5 \le \gamma \le 8$ | ||||||
$\overline{\Q}$-gonality: | $5 \le \gamma \le 8$ | ||||||
Rational cusps: | $0$ | ||||||
Rational CM points: | none |
Other labels
Cummins and Pauli (CP) label: | 40G13 |
Rouse, Sutherland, and Zureick-Brown (RSZB) label: | 40.480.13.1443 |
Level structure
$\GL_2(\Z/40\Z)$-generators: | $\begin{bmatrix}5&29\\8&5\end{bmatrix}$, $\begin{bmatrix}9&18\\32&1\end{bmatrix}$, $\begin{bmatrix}15&19\\28&25\end{bmatrix}$, $\begin{bmatrix}27&33\\4&19\end{bmatrix}$ |
Contains $-I$: | no $\quad$ (see 40.240.13.oz.1 for the level structure with $-I$) |
Cyclic 40-isogeny field degree: | $12$ |
Cyclic 40-torsion field degree: | $96$ |
Full 40-torsion field degree: | $1536$ |
Jacobian
Conductor: | $2^{54}\cdot5^{26}$ |
Simple: | no |
Squarefree: | no |
Decomposition: | $1^{13}$ |
Newforms: | 50.2.a.b$^{4}$, 100.2.a.a, 1600.2.a.a$^{2}$, 1600.2.a.c, 1600.2.a.f, 1600.2.a.o, 1600.2.a.q$^{2}$, 1600.2.a.v |
Models
Canonical model in $\mathbb{P}^{ 12 }$ defined by 55 equations
$ 0 $ | $=$ | $ x z - x t + y w - y t $ |
$=$ | $2 x^{2} + x y + 2 y^{2} - z^{2} - z w - z t - w^{2} - w t$ | |
$=$ | $x z - 2 x w + x t - 2 y z + y w + y t + s^{2} - s b + a^{2} + a c + b c$ | |
$=$ | $x y + 2 x z + 2 x w - 2 y w + z^{2} - z w + z t + w^{2} + w t - s^{2} - s b + a b - a c + a d$ | |
$=$ | $\cdots$ |
Rational points
This modular curve has no real points and no $\Q_p$ points for $p=13,17$, and therefore no rational points.
Maps to other modular curves
Map of degree 4 from the canonical model of this modular curve to the canonical model of the modular curve 20.60.3.c.1 :
$\displaystyle X$ | $=$ | $\displaystyle 5x+5y-2z-2w-t$ |
$\displaystyle Y$ | $=$ | $\displaystyle -3z-3w+t$ |
$\displaystyle Z$ | $=$ | $\displaystyle z+w+3t$ |
Equation of the image curve:
$0$ | $=$ | $ 2X^{4}-4X^{3}Y+6X^{2}Y^{2}-4XY^{3}+2Y^{4}+4X^{3}Z+17X^{2}YZ-17XY^{2}Z-4Y^{3}Z+5X^{2}Z^{2}+18XYZ^{2}+5Y^{2}Z^{2}+3XZ^{3}-3YZ^{3}-2Z^{4} $ |
Modular covers
The following modular covers realize this modular curve as a fiber product over $X(1)$.
Factor curve | Level | Index | Degree | Genus | Rank | Kernel decomposition |
---|---|---|---|---|---|---|
5.20.0.b.1 | $5$ | $24$ | $12$ | $0$ | $0$ | full Jacobian |
8.24.0-8.p.1.7 | $8$ | $20$ | $20$ | $0$ | $0$ | full Jacobian |
This modular curve minimally covers the modular curves listed below.
Covered curve | Level | Index | Degree | Genus | Rank | Kernel decomposition |
---|---|---|---|---|---|---|
40.120.4-40.br.1.13 | $40$ | $4$ | $4$ | $4$ | $2$ | $1^{9}$ |
40.240.5-20.m.1.3 | $40$ | $2$ | $2$ | $5$ | $0$ | $1^{8}$ |
40.240.5-20.m.1.8 | $40$ | $2$ | $2$ | $5$ | $0$ | $1^{8}$ |
40.240.7-40.co.1.18 | $40$ | $2$ | $2$ | $7$ | $2$ | $1^{6}$ |
40.240.7-40.co.1.23 | $40$ | $2$ | $2$ | $7$ | $2$ | $1^{6}$ |
40.240.7-40.cx.1.19 | $40$ | $2$ | $2$ | $7$ | $4$ | $1^{6}$ |
40.240.7-40.cx.1.22 | $40$ | $2$ | $2$ | $7$ | $4$ | $1^{6}$ |
This modular curve is minimally covered by the modular curves in the database listed below.
Covering curve | Level | Index | Degree | Genus | Rank | Kernel decomposition |
---|---|---|---|---|---|---|
40.960.29-40.hc.1.12 | $40$ | $2$ | $2$ | $29$ | $9$ | $1^{16}$ |
40.960.29-40.ib.1.7 | $40$ | $2$ | $2$ | $29$ | $9$ | $1^{16}$ |
40.960.29-40.qs.1.2 | $40$ | $2$ | $2$ | $29$ | $15$ | $1^{16}$ |
40.960.29-40.qu.1.8 | $40$ | $2$ | $2$ | $29$ | $15$ | $1^{16}$ |
40.960.29-40.yp.1.4 | $40$ | $2$ | $2$ | $29$ | $14$ | $1^{16}$ |
40.960.29-40.yr.1.3 | $40$ | $2$ | $2$ | $29$ | $14$ | $1^{16}$ |
40.960.29-40.yx.1.3 | $40$ | $2$ | $2$ | $29$ | $9$ | $1^{16}$ |
40.960.29-40.yz.1.4 | $40$ | $2$ | $2$ | $29$ | $9$ | $1^{16}$ |
40.1440.37-40.mv.1.3 | $40$ | $3$ | $3$ | $37$ | $14$ | $1^{24}$ |