Properties

Label 38.240.8-38.a.1.1
Level $38$
Index $240$
Genus $8$
Analytic rank $0$
Cusps $6$
$\Q$-cusps $6$

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Invariants

Level: $38$ $\SL_2$-level: $38$ Newform level: $76$
Index: $240$ $\PSL_2$-index:$120$
Genus: $8 = 1 + \frac{ 120 }{12} - \frac{ 0 }{4} - \frac{ 0 }{3} - \frac{ 6 }{2}$
Cusps: $6$ (all of which are rational) Cusp widths $2^{3}\cdot38^{3}$ Cusp orbits $1^{6}$
Elliptic points: $0$ of order $2$ and $0$ of order $3$
Analytic rank: $0$
$\Q$-gonality: $4 \le \gamma \le 6$
$\overline{\Q}$-gonality: $4 \le \gamma \le 6$
Rational cusps: $6$
Rational CM points: none

Other labels

Cummins and Pauli (CP) label: 38A8
Rouse, Sutherland, and Zureick-Brown (RSZB) label: 38.240.8.1

Level structure

$\GL_2(\Z/38\Z)$-generators: $\begin{bmatrix}7&0\\0&29\end{bmatrix}$, $\begin{bmatrix}23&12\\0&33\end{bmatrix}$
Contains $-I$: no $\quad$ (see 38.120.8.a.1 for the level structure with $-I$)
Cyclic 38-isogeny field degree: $1$
Cyclic 38-torsion field degree: $9$
Full 38-torsion field degree: $3078$

Jacobian

Conductor: $2^{6}\cdot19^{8}$
Simple: no
Squarefree: no
Decomposition: $1^{8}$
Newforms: 19.2.a.a$^{3}$, 38.2.a.a$^{2}$, 38.2.a.b$^{2}$, 76.2.a.a

Models

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

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

$ 0 $ $=$ $ 64 x^{12} - 352 x^{11} y + 960 x^{10} y^{2} - 80 x^{10} y z + 96 x^{10} z^{2} - 1724 x^{9} y^{3} + \cdots + y^{6} z^{6} $
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Rational points

This modular curve has 6 rational cusps but no known non-cuspidal rational points. The following are the coordinates of the rational cusps on this modular curve.

Canonical model
$(1:1:0:1:0:-1:1:1)$, $(1:1:0:0:0:-1:1:0)$, $(0:0:0:0:0:0:0:1)$, $(0:1:2:1:0:0:1:1)$, $(0:1:1:0:0:0:1:1)$, $(0:0:1:0:0:0:0:0)$

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 $X_0(38)$ :

$\displaystyle X$ $=$ $\displaystyle x-y+r$
$\displaystyle Y$ $=$ $\displaystyle -x-t-u$
$\displaystyle Z$ $=$ $\displaystyle -x+y-z+r$
$\displaystyle W$ $=$ $\displaystyle -x+v-r$

Equation of the image curve:

$0$ $=$ $ X^{2}-XY+2XZ-YZ+2XW-YW+ZW $
$=$ $ Y^{3}-X^{2}Z+XZ^{2}+X^{2}W-XYW+YZW+2XW^{2}+YW^{2}-ZW^{2} $

Map of degree 1 from the canonical model of this modular curve to the plane model of the modular curve 38.120.8.a.1 :

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

Equation of the image curve:

$0$ $=$ $ 64X^{12}-352X^{11}Y+960X^{10}Y^{2}-80X^{10}YZ+96X^{10}Z^{2}-1724X^{9}Y^{3}+296X^{9}Y^{2}Z-352X^{9}YZ^{2}+64X^{9}Z^{3}+2265X^{8}Y^{4}-594X^{8}Y^{3}Z+488X^{8}Y^{2}Z^{2}-280X^{8}YZ^{3}+144X^{8}Z^{4}-2278X^{7}Y^{5}+927X^{7}Y^{4}Z-330X^{7}Y^{3}Z^{2}+280X^{7}Y^{2}Z^{3}-280X^{7}YZ^{4}+48X^{7}Z^{5}+1762X^{6}Y^{6}-1125X^{6}Y^{5}Z+170X^{6}Y^{4}Z^{2}+96X^{6}Y^{3}Z^{3}+68X^{6}Y^{2}Z^{4}-80X^{6}YZ^{5}+16X^{6}Z^{6}-1016X^{5}Y^{7}+949X^{5}Y^{6}Z-198X^{5}Y^{5}Z^{2}-273X^{5}Y^{4}Z^{3}+216X^{5}Y^{3}Z^{4}-4X^{5}Y^{2}Z^{5}-16X^{5}YZ^{6}+412X^{4}Y^{8}-514X^{4}Y^{7}Z+225X^{4}Y^{6}Z^{2}+69X^{4}Y^{5}Z^{3}-175X^{4}Y^{4}Z^{4}+80X^{4}Y^{3}Z^{5}-12X^{4}Y^{2}Z^{6}-108X^{3}Y^{9}+167X^{3}Y^{8}Z-138X^{3}Y^{7}Z^{2}+90X^{3}Y^{6}Z^{3}-40X^{3}Y^{4}Z^{5}+16X^{3}Y^{3}Z^{6}+16X^{2}Y^{10}-29X^{2}Y^{9}Z+42X^{2}Y^{8}Z^{2}-65X^{2}Y^{7}Z^{3}+51X^{2}Y^{6}Z^{4}-14X^{2}Y^{5}Z^{5}-XY^{11}+2XY^{10}Z-5XY^{9}Z^{2}+15XY^{8}Z^{3}-22XY^{7}Z^{4}+15XY^{6}Z^{5}-4XY^{5}Z^{6}-Y^{9}Z^{3}+3Y^{8}Z^{4}-3Y^{7}Z^{5}+Y^{6}Z^{6} $

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
$X(2)$ $2$ $40$ $20$ $0$ $0$ full Jacobian
19.40.1-19.a.1.2 $19$ $6$ $6$ $1$ $0$ $1^{7}$

This modular curve minimally covers the modular curves listed below.

Covered curve Level Index Degree Genus Rank Kernel decomposition
38.80.2-38.a.1.1 $38$ $3$ $3$ $2$ $0$ $1^{6}$
38.120.4-38.a.1.2 $38$ $2$ $2$ $4$ $0$ $1^{4}$
38.120.4-38.a.1.3 $38$ $2$ $2$ $4$ $0$ $1^{4}$

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

Covering curve Level Index Degree Genus Rank Kernel decomposition
38.720.22-38.a.1.1 $38$ $3$ $3$ $22$ $0$ $2^{3}\cdot4^{2}$
38.720.22-38.a.2.2 $38$ $3$ $3$ $22$ $0$ $2^{3}\cdot4^{2}$
38.720.22-38.b.1.1 $38$ $3$ $3$ $22$ $4$ $1^{6}\cdot2^{4}$
38.4560.161-38.a.1.1 $38$ $19$ $19$ $161$ $56$ $1^{29}\cdot2^{23}\cdot3^{10}\cdot4^{7}\cdot6^{2}\cdot8$
76.480.16-76.a.1.2 $76$ $2$ $2$ $16$ $?$ not computed
76.480.16-76.a.2.4 $76$ $2$ $2$ $16$ $?$ not computed
76.480.17-76.a.1.2 $76$ $2$ $2$ $17$ $?$ not computed
76.480.17-76.b.1.2 $76$ $2$ $2$ $17$ $?$ not computed
76.480.17-76.c.1.2 $76$ $2$ $2$ $17$ $?$ not computed
76.480.17-76.d.1.2 $76$ $2$ $2$ $17$ $?$ not computed
76.480.18-76.a.1.6 $76$ $2$ $2$ $18$ $?$ not computed
76.480.18-76.a.2.8 $76$ $2$ $2$ $18$ $?$ not computed
152.480.16-152.a.1.4 $152$ $2$ $2$ $16$ $?$ not computed
152.480.16-152.a.2.8 $152$ $2$ $2$ $16$ $?$ not computed
152.480.17-152.a.1.6 $152$ $2$ $2$ $17$ $?$ not computed
152.480.17-152.b.1.6 $152$ $2$ $2$ $17$ $?$ not computed
152.480.17-152.c.1.8 $152$ $2$ $2$ $17$ $?$ not computed
152.480.17-152.d.1.8 $152$ $2$ $2$ $17$ $?$ not computed
152.480.18-152.a.1.11 $152$ $2$ $2$ $18$ $?$ not computed
152.480.18-152.a.2.14 $152$ $2$ $2$ $18$ $?$ not computed
228.480.16-228.a.1.4 $228$ $2$ $2$ $16$ $?$ not computed
228.480.16-228.a.2.8 $228$ $2$ $2$ $16$ $?$ not computed
228.480.17-228.a.1.3 $228$ $2$ $2$ $17$ $?$ not computed
228.480.17-228.b.1.4 $228$ $2$ $2$ $17$ $?$ not computed
228.480.17-228.c.1.4 $228$ $2$ $2$ $17$ $?$ not computed
228.480.17-228.d.1.4 $228$ $2$ $2$ $17$ $?$ not computed
228.480.18-228.a.1.9 $228$ $2$ $2$ $18$ $?$ not computed
228.480.18-228.a.2.10 $228$ $2$ $2$ $18$ $?$ not computed