Properties

Label 4.4.al_ci_ahz_sz
Base field $\F_{2^{2}}$
Dimension $4$
$p$-rank $4$
Ordinary yes
Supersingular no
Simple no
Geometrically simple no
Primitive yes
Principally polarizable yes
Contains a Jacobian no

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Invariants

Base field:  $\F_{2^{2}}$
Dimension:  $4$
L-polynomial:  $( 1 - 3 x + 4 x^{2} )^{2}( 1 - 5 x + 13 x^{2} - 20 x^{3} + 16 x^{4} )$
  $1 - 11 x + 60 x^{2} - 207 x^{3} + 493 x^{4} - 828 x^{5} + 960 x^{6} - 704 x^{7} + 256 x^{8}$
Frobenius angles:  $\pm0.140237960897$, $\pm0.230053456163$, $\pm0.230053456163$, $\pm0.387712212190$
Angle rank:  $3$ (numerical)

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

Newton polygon

This isogeny class is ordinary.

$p$-rank:  $4$
Slopes:  $[0, 0, 0, 0, 1, 1, 1, 1]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $20$ $70400$ $26394320$ $5497113600$ $1197211630500$

Point counts of the (virtual) curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $-6$ $16$ $93$ $320$ $1114$ $4237$ $16626$ $65600$ $260877$ $1044896$

Jacobians and polarizations

This isogeny class is principally polarizable, but does not contain a Jacobian.

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{2^{2}}$.

Endomorphism algebra over $\F_{2^{2}}$
The isogeny class factors as 1.4.ad 2 $\times$ 2.4.af_n and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. The endomorphism algebra for each factor is:

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
4.4.af_m_ap_t$2$(not in LMFDB)
4.4.ab_a_d_n$2$(not in LMFDB)
4.4.b_a_ad_n$2$(not in LMFDB)
4.4.f_m_p_t$2$(not in LMFDB)
4.4.l_ci_hz_sz$2$(not in LMFDB)
4.4.ac_d_g_ax$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
4.4.af_m_ap_t$2$(not in LMFDB)
4.4.ab_a_d_n$2$(not in LMFDB)
4.4.b_a_ad_n$2$(not in LMFDB)
4.4.f_m_p_t$2$(not in LMFDB)
4.4.l_ci_hz_sz$2$(not in LMFDB)
4.4.ac_d_g_ax$3$(not in LMFDB)
4.4.af_o_az_bt$4$(not in LMFDB)
4.4.f_o_z_bt$4$(not in LMFDB)
4.4.ai_bh_ads_ij$6$(not in LMFDB)
4.4.c_d_ag_ax$6$(not in LMFDB)
4.4.i_bh_ds_ij$6$(not in LMFDB)