Properties

Label 2.5.ag_t
Base field $\F_{5}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple no
Geometrically simple no
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{5}$
Dimension:  $2$
L-polynomial:  $( 1 - 3 x + 5 x^{2} )^{2}$
  $1 - 6 x + 19 x^{2} - 30 x^{3} + 25 x^{4}$
Frobenius angles:  $\pm0.265942140215$, $\pm0.265942140215$
Angle rank:  $1$ (numerical)
Jacobians:  $1$

This isogeny class is not simple, primitive, ordinary, and not supersingular. It is principally polarizable and contains a Jacobian.

Newton polygon

This isogeny class is ordinary.

$p$-rank:  $2$
Slopes:  $[0, 0, 1, 1]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $9$ $729$ $20736$ $455625$ $10131489$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $0$ $28$ $162$ $724$ $3240$ $15478$ $77112$ $388324$ $1951290$ $9771628$

Jacobians and polarizations

This isogeny class contains the Jacobian of 1 curve (which is hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{5}$.

Endomorphism algebra over $\F_{5}$
The isogeny class factors as 1.5.ad 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-11}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.5.a_b$2$2.25.c_bz
2.5.g_t$2$2.25.c_bz
2.5.d_e$3$2.125.bk_wc

Below is a list of all twists of this isogeny class.

TwistExtension degreeCommon base change
2.5.a_b$2$2.25.c_bz
2.5.g_t$2$2.25.c_bz
2.5.d_e$3$2.125.bk_wc
2.5.a_ab$4$2.625.du_fkl
2.5.ad_e$6$(not in LMFDB)