Properties

Label 40.20.1.a.1
Level $40$
Index $20$
Genus $1$
Analytic rank $0$
Cusps $2$
$\Q$-cusps $0$

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Invariants

Level: $40$ $\SL_2$-level: $10$ Newform level: $1600$
Index: $20$ $\PSL_2$-index:$20$
Genus: $1 = 1 + \frac{ 20 }{12} - \frac{ 0 }{4} - \frac{ 2 }{3} - \frac{ 2 }{2}$
Cusps: $2$ (none of which are rational) Cusp widths $10^{2}$ Cusp orbits $2$
Elliptic points: $0$ of order $2$ and $2$ of order $3$
Analytic rank: $0$
$\Q$-gonality: $2$
$\overline{\Q}$-gonality: $2$
Rational cusps: $0$
Rational CM points: none

Other labels

Cummins and Pauli (CP) label: 10C1
Rouse, Sutherland, and Zureick-Brown (RSZB) label: 40.20.1.1

Level structure

$\GL_2(\Z/40\Z)$-generators: $\begin{bmatrix}5&12\\3&23\end{bmatrix}$, $\begin{bmatrix}9&12\\8&11\end{bmatrix}$, $\begin{bmatrix}37&20\\23&13\end{bmatrix}$, $\begin{bmatrix}39&7\\23&12\end{bmatrix}$
Contains $-I$: yes
Quadratic refinements: none in database
Cyclic 40-isogeny field degree: $72$
Cyclic 40-torsion field degree: $1152$
Full 40-torsion field degree: $36864$

Jacobian

Conductor: $2^{6}\cdot5^{2}$
Simple: yes
Squarefree: yes
Decomposition: $1$
Newforms: 1600.2.a.w

Models

Embedded model Embedded model in $\mathbb{P}^{3}$

$ 0 $ $=$ $ 2 x z - x w + y z - y w $
$=$ $6 x^{2} + 8 x y + 16 y^{2} - z^{2} + 3 z w - w^{2}$
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Singular plane model Singular plane model

$ 0 $ $=$ $ 4 x^{4} - 16 x^{3} z - 54 x^{2} y^{2} + 17 x^{2} z^{2} + 52 x y^{2} z - 7 x z^{3} - 14 y^{2} z^{2} + z^{4} $
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Rational points

This modular curve has real points and $\Q_p$ points for $p$ not dividing the level, but no known rational points.

Maps between models of this curve

Birational map from embedded model to plane model:

$\displaystyle X$ $=$ $\displaystyle z$
$\displaystyle Y$ $=$ $\displaystyle y$
$\displaystyle Z$ $=$ $\displaystyle w$

Maps to other modular curves

$j$-invariant map of degree 20 from the embedded model of this modular curve to the modular curve $X(1)$ :

$\displaystyle j$ $=$ $\displaystyle 5^3\,\frac{317634048xy^{5}+17556672xy^{3}w^{2}-5594808xyw^{4}+244477440y^{6}+115146304y^{4}w^{2}-255928y^{2}w^{4}-34816z^{6}+186880z^{5}w-1534656z^{4}w^{2}+4368424z^{3}w^{3}-6566455z^{2}w^{4}+3954621zw^{5}-928931w^{6}}{22977000xy^{5}+2315500xy^{3}w^{2}+14250xyw^{4}+17685000y^{6}+5371000y^{4}w^{2}+121750y^{2}w^{4}-2327z^{6}+18112z^{5}w-67714z^{4}w^{2}+160194z^{3}w^{3}-209749z^{2}w^{4}+108617zw^{5}-18512w^{6}}$

Modular covers

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Cover information

Click on a modular curve in the diagram to see information about it.

The following modular covers realize this modular curve as a fiber product over $X(1)$.

Factor curve Level Index Degree Genus Rank Kernel decomposition
$X_{\mathrm{ns}}^+(5)$ $5$ $2$ $2$ $0$ $0$ full Jacobian
8.2.0.a.1 $8$ $10$ $10$ $0$ $0$ full Jacobian

This modular curve minimally covers the modular curves listed below.

Covered curve Level Index Degree Genus Rank Kernel decomposition
$X_{\mathrm{ns}}^+(5)$ $5$ $2$ $2$ $0$ $0$ full Jacobian
8.2.0.a.1 $8$ $10$ $10$ $0$ $0$ full Jacobian

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

Covering curve Level Index Degree Genus Rank Kernel decomposition
40.40.1.b.1 $40$ $2$ $2$ $1$ $0$ dimension zero
40.40.1.c.1 $40$ $2$ $2$ $1$ $0$ dimension zero
40.40.1.e.1 $40$ $2$ $2$ $1$ $0$ dimension zero
40.40.1.f.1 $40$ $2$ $2$ $1$ $0$ dimension zero
40.40.1.n.1 $40$ $2$ $2$ $1$ $0$ dimension zero
40.40.1.o.1 $40$ $2$ $2$ $1$ $0$ dimension zero
40.40.1.q.1 $40$ $2$ $2$ $1$ $0$ dimension zero
40.40.1.r.1 $40$ $2$ $2$ $1$ $0$ dimension zero
40.60.3.a.1 $40$ $3$ $3$ $3$ $0$ $1^{2}$
40.60.3.r.1 $40$ $3$ $3$ $3$ $1$ $1^{2}$
40.80.5.a.1 $40$ $4$ $4$ $5$ $4$ $1^{4}$
120.40.1.b.1 $120$ $2$ $2$ $1$ $?$ dimension zero
120.40.1.c.1 $120$ $2$ $2$ $1$ $?$ dimension zero
120.40.1.e.1 $120$ $2$ $2$ $1$ $?$ dimension zero
120.40.1.f.1 $120$ $2$ $2$ $1$ $?$ dimension zero
120.40.1.n.1 $120$ $2$ $2$ $1$ $?$ dimension zero
120.40.1.o.1 $120$ $2$ $2$ $1$ $?$ dimension zero
120.40.1.q.1 $120$ $2$ $2$ $1$ $?$ dimension zero
120.40.1.r.1 $120$ $2$ $2$ $1$ $?$ dimension zero
120.60.5.bw.1 $120$ $3$ $3$ $5$ $?$ not computed
120.80.5.a.1 $120$ $4$ $4$ $5$ $?$ not computed
200.100.5.a.1 $200$ $5$ $5$ $5$ $?$ not computed
280.40.1.b.1 $280$ $2$ $2$ $1$ $?$ dimension zero
280.40.1.c.1 $280$ $2$ $2$ $1$ $?$ dimension zero
280.40.1.e.1 $280$ $2$ $2$ $1$ $?$ dimension zero
280.40.1.f.1 $280$ $2$ $2$ $1$ $?$ dimension zero
280.40.1.n.1 $280$ $2$ $2$ $1$ $?$ dimension zero
280.40.1.o.1 $280$ $2$ $2$ $1$ $?$ dimension zero
280.40.1.q.1 $280$ $2$ $2$ $1$ $?$ dimension zero
280.40.1.r.1 $280$ $2$ $2$ $1$ $?$ dimension zero
280.160.11.a.1 $280$ $8$ $8$ $11$ $?$ not computed