Properties

Label 40.240.8-40.c.1.18
Level $40$
Index $240$
Genus $8$
Analytic rank $2$
Cusps $6$
$\Q$-cusps $2$

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Invariants

Level: $40$ $\SL_2$-level: $40$ Newform level: $1600$
Index: $240$ $\PSL_2$-index:$120$
Genus: $8 = 1 + \frac{ 120 }{12} - \frac{ 0 }{4} - \frac{ 0 }{3} - \frac{ 6 }{2}$
Cusps: $6$ (of which $2$ are rational) Cusp widths $20^{6}$ Cusp orbits $1^{2}\cdot2^{2}$
Elliptic points: $0$ of order $2$ and $0$ of order $3$
Analytic rank: $2$
$\Q$-gonality: $3 \le \gamma \le 5$
$\overline{\Q}$-gonality: $3 \le \gamma \le 5$
Rational cusps: $2$
Rational CM points: none

Other labels

Cummins and Pauli (CP) label: 20A8
Rouse, Sutherland, and Zureick-Brown (RSZB) label: 40.240.8.663

Level structure

$\GL_2(\Z/40\Z)$-generators: $\begin{bmatrix}3&2\\36&21\end{bmatrix}$, $\begin{bmatrix}23&22\\28&33\end{bmatrix}$, $\begin{bmatrix}25&38\\34&25\end{bmatrix}$, $\begin{bmatrix}27&38\\28&13\end{bmatrix}$, $\begin{bmatrix}29&26\\16&11\end{bmatrix}$
Contains $-I$: no $\quad$ (see 40.120.8.c.1 for the level structure with $-I$)
Cyclic 40-isogeny field degree: $12$
Cyclic 40-torsion field degree: $192$
Full 40-torsion field degree: $3072$

Jacobian

Conductor: $2^{30}\cdot5^{16}$
Simple: no
Squarefree: no
Decomposition: $1^{8}$
Newforms: 50.2.a.b$^{3}$, 200.2.a.e, 1600.2.a.a, 1600.2.a.i, 1600.2.a.q, 1600.2.a.y

Models

Canonical model in $\mathbb{P}^{ 7 }$ defined by 15 equations

$ 0 $ $=$ $ x t + x r + y r + z v $
$=$ $2 x r - y t + w v$
$=$ $x u + x v + y u - z r - w t$
$=$ $2 x w + 2 y z + u r + v r$
$=$$\cdots$
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Singular plane model Singular plane model

$ 0 $ $=$ $ - 32 x^{10} - 16 x^{8} y^{2} + 32 x^{8} z^{2} - 2 x^{6} y^{4} + 44 x^{6} y^{2} z^{2} + \cdots + 8 y^{2} z^{8} $
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Rational points

This modular curve has 2 rational cusps but no known non-cuspidal rational points. The following are the coordinates of the rational cusps on this modular curve.

Canonical model
$(0:0:0:0:1:-1:1:0)$, $(0:0:0:0:-1:-1:1:0)$

Maps to other modular curves

Map of degree 2 from the canonical model of this modular curve to the canonical model of the modular curve 20.60.4.b.1 :

$\displaystyle X$ $=$ $\displaystyle x$
$\displaystyle Y$ $=$ $\displaystyle y$
$\displaystyle Z$ $=$ $\displaystyle z$
$\displaystyle W$ $=$ $\displaystyle -w$

Equation of the image curve:

$0$ $=$ $ X^{2}+XY+2Y^{2}-Z^{2}-ZW $
$=$ $ 2X^{2}Y+2XY^{2}+2XZW+YZW+XW^{2}+YW^{2} $

Map of degree 1 from the canonical model of this modular curve to the plane model of the modular curve 40.120.8.c.1 :

$\displaystyle X$ $=$ $\displaystyle x$
$\displaystyle Y$ $=$ $\displaystyle w$
$\displaystyle Z$ $=$ $\displaystyle \frac{1}{2}t$

Equation of the image curve:

$0$ $=$ $ -32X^{10}-16X^{8}Y^{2}+32X^{8}Z^{2}-2X^{6}Y^{4}+44X^{6}Y^{2}Z^{2}-8X^{6}Z^{4}-X^{4}Y^{4}Z^{2}+2X^{4}Y^{2}Z^{4}-6X^{2}Y^{6}Z^{2}-8X^{2}Y^{4}Z^{4}-24X^{2}Y^{2}Z^{6}-Y^{8}Z^{2}+6Y^{6}Z^{4}-12Y^{4}Z^{6}+8Y^{2}Z^{8} $

Modular covers

This modular curve minimally covers the modular curves listed below.

Covered curve Level Index Degree Genus Rank Kernel decomposition
40.48.0-8.c.1.7 $40$ $5$ $5$ $0$ $0$ full Jacobian
40.120.4-20.b.1.15 $40$ $2$ $2$ $4$ $0$ $1^{4}$
40.120.4-20.b.1.18 $40$ $2$ $2$ $4$ $0$ $1^{4}$

This modular curve is minimally covered by the modular curves in the database listed below.

Covering curve Level Index Degree Genus Rank Kernel decomposition
40.480.16-40.g.1.4 $40$ $2$ $2$ $16$ $6$ $2^{4}$
40.480.16-40.g.1.13 $40$ $2$ $2$ $16$ $6$ $2^{4}$
40.480.16-40.h.1.8 $40$ $2$ $2$ $16$ $2$ $2^{4}$
40.480.16-40.h.1.9 $40$ $2$ $2$ $16$ $2$ $2^{4}$
40.480.16-40.i.1.8 $40$ $2$ $2$ $16$ $2$ $2^{4}$
40.480.16-40.i.1.15 $40$ $2$ $2$ $16$ $2$ $2^{4}$
40.480.16-40.i.2.7 $40$ $2$ $2$ $16$ $2$ $2^{4}$
40.480.16-40.i.2.16 $40$ $2$ $2$ $16$ $2$ $2^{4}$
40.480.16-40.j.1.6 $40$ $2$ $2$ $16$ $4$ $2^{4}$
40.480.16-40.j.1.16 $40$ $2$ $2$ $16$ $4$ $2^{4}$
40.480.16-40.j.2.6 $40$ $2$ $2$ $16$ $4$ $2^{4}$
40.480.16-40.j.2.16 $40$ $2$ $2$ $16$ $4$ $2^{4}$
40.480.16-40.k.1.4 $40$ $2$ $2$ $16$ $2$ $2^{4}$
40.480.16-40.k.1.13 $40$ $2$ $2$ $16$ $2$ $2^{4}$
40.480.16-40.l.1.2 $40$ $2$ $2$ $16$ $2$ $2^{4}$
40.480.16-40.l.1.15 $40$ $2$ $2$ $16$ $2$ $2^{4}$
40.480.17-40.bd.1.6 $40$ $2$ $2$ $17$ $5$ $1^{7}\cdot2$
40.480.17-40.bd.1.12 $40$ $2$ $2$ $17$ $5$ $1^{7}\cdot2$
40.480.17-40.bi.1.3 $40$ $2$ $2$ $17$ $6$ $1^{7}\cdot2$
40.480.17-40.bi.1.16 $40$ $2$ $2$ $17$ $6$ $1^{7}\cdot2$
40.480.17-40.br.1.7 $40$ $2$ $2$ $17$ $5$ $1^{7}\cdot2$
40.480.17-40.br.1.16 $40$ $2$ $2$ $17$ $5$ $1^{7}\cdot2$
40.480.17-40.bt.1.8 $40$ $2$ $2$ $17$ $5$ $1^{7}\cdot2$
40.480.17-40.bt.1.14 $40$ $2$ $2$ $17$ $5$ $1^{7}\cdot2$
40.720.22-40.c.1.31 $40$ $3$ $3$ $22$ $6$ $1^{14}$
40.960.29-40.t.1.16 $40$ $4$ $4$ $29$ $9$ $1^{21}$
120.480.16-120.g.1.11 $120$ $2$ $2$ $16$ $?$ not computed
120.480.16-120.g.1.29 $120$ $2$ $2$ $16$ $?$ not computed
120.480.16-120.h.1.7 $120$ $2$ $2$ $16$ $?$ not computed
120.480.16-120.h.1.27 $120$ $2$ $2$ $16$ $?$ not computed
120.480.16-120.i.1.3 $120$ $2$ $2$ $16$ $?$ not computed
120.480.16-120.i.1.29 $120$ $2$ $2$ $16$ $?$ not computed
120.480.16-120.i.2.7 $120$ $2$ $2$ $16$ $?$ not computed
120.480.16-120.i.2.27 $120$ $2$ $2$ $16$ $?$ not computed
120.480.16-120.j.1.4 $120$ $2$ $2$ $16$ $?$ not computed
120.480.16-120.j.1.21 $120$ $2$ $2$ $16$ $?$ not computed
120.480.16-120.j.2.11 $120$ $2$ $2$ $16$ $?$ not computed
120.480.16-120.j.2.20 $120$ $2$ $2$ $16$ $?$ not computed
120.480.16-120.k.1.8 $120$ $2$ $2$ $16$ $?$ not computed
120.480.16-120.k.1.11 $120$ $2$ $2$ $16$ $?$ not computed
120.480.16-120.l.1.3 $120$ $2$ $2$ $16$ $?$ not computed
120.480.16-120.l.1.16 $120$ $2$ $2$ $16$ $?$ not computed
120.480.17-120.bo.1.4 $120$ $2$ $2$ $17$ $?$ not computed
120.480.17-120.bo.1.26 $120$ $2$ $2$ $17$ $?$ not computed
120.480.17-120.br.1.12 $120$ $2$ $2$ $17$ $?$ not computed
120.480.17-120.br.1.18 $120$ $2$ $2$ $17$ $?$ not computed
120.480.17-120.ca.1.14 $120$ $2$ $2$ $17$ $?$ not computed
120.480.17-120.ca.1.18 $120$ $2$ $2$ $17$ $?$ not computed
120.480.17-120.cd.1.6 $120$ $2$ $2$ $17$ $?$ not computed
120.480.17-120.cd.1.26 $120$ $2$ $2$ $17$ $?$ not computed
280.480.16-280.g.1.9 $280$ $2$ $2$ $16$ $?$ not computed
280.480.16-280.g.1.31 $280$ $2$ $2$ $16$ $?$ not computed
280.480.16-280.h.1.11 $280$ $2$ $2$ $16$ $?$ not computed
280.480.16-280.h.1.23 $280$ $2$ $2$ $16$ $?$ not computed
280.480.16-280.i.1.11 $280$ $2$ $2$ $16$ $?$ not computed
280.480.16-280.i.1.21 $280$ $2$ $2$ $16$ $?$ not computed
280.480.16-280.i.2.11 $280$ $2$ $2$ $16$ $?$ not computed
280.480.16-280.i.2.23 $280$ $2$ $2$ $16$ $?$ not computed
280.480.16-280.j.1.5 $280$ $2$ $2$ $16$ $?$ not computed
280.480.16-280.j.1.20 $280$ $2$ $2$ $16$ $?$ not computed
280.480.16-280.j.2.11 $280$ $2$ $2$ $16$ $?$ not computed
280.480.16-280.j.2.20 $280$ $2$ $2$ $16$ $?$ not computed
280.480.16-280.k.1.11 $280$ $2$ $2$ $16$ $?$ not computed
280.480.16-280.k.1.20 $280$ $2$ $2$ $16$ $?$ not computed
280.480.16-280.l.1.3 $280$ $2$ $2$ $16$ $?$ not computed
280.480.16-280.l.1.24 $280$ $2$ $2$ $16$ $?$ not computed
280.480.17-280.bo.1.2 $280$ $2$ $2$ $17$ $?$ not computed
280.480.17-280.bo.1.30 $280$ $2$ $2$ $17$ $?$ not computed
280.480.17-280.br.1.4 $280$ $2$ $2$ $17$ $?$ not computed
280.480.17-280.br.1.26 $280$ $2$ $2$ $17$ $?$ not computed
280.480.17-280.ca.1.10 $280$ $2$ $2$ $17$ $?$ not computed
280.480.17-280.ca.1.20 $280$ $2$ $2$ $17$ $?$ not computed
280.480.17-280.cd.1.2 $280$ $2$ $2$ $17$ $?$ not computed
280.480.17-280.cd.1.24 $280$ $2$ $2$ $17$ $?$ not computed