Argus Case File: ZTF18abujsbq

Static evidence report generated from the local case-file JSON.

Evidence Narrative

Complex light-curve behavior with limited physical interpretation

The object is not well explained by a single smooth bump. Its r-band detections show repeated or irregular variability texture, while template and catalog-context checks remain limited by available context.

Evidence Sections

Baseline transient-shape check not_well_fit
The Gaussian bump comparator fit the detections but left substantial residual structure (reduced chi-squared about 2.4).
Variability texture complex_variability
The light curve shows repeated or irregular directional changes (8 smoothed turn(s)) beyond a simple smooth event shape.
Standard feature summary computed
Descriptive light-curve features were computed from 145 usable r-band point(s) for comparison across objects.
Template-family probe limited
Template-family probing was limited because required context such as redshift is unavailable.
Cross-survey context not_requested
External catalog context was not requested for this case-file run.

What Argus Can Say

The r-band detections are not well explained by a single smooth bump.
The r-band detections show repeated or irregular variability texture.
Standard descriptive features are available for comparison across objects.
No spectroscopic information is recorded in this case file.

What Argus Cannot Say

Argus does not identify the object type.
Argus does not certify that the source is unusual.
Argus does not treat broker or catalog labels as ground truth.
Argus does not treat template-family probes as object identity.

Recommended Next Checks

Inspect residual structure visually.
Compare against known repeated-variability behavior.
Add verified redshift or context before interpreting template-family probes.
Run cross-survey context if network access and optional dependencies are available.
Inspect forced photometry around recent detections if available.

Caveat: This narrative summarizes evidence layers. It is not a physical classification.

Visual Summary

Gaussian comparator residuals show where the simple bump model under- or over-predicts the observed magnitudes.

Object Summary

Object ID: ZTF18abujsbq
Source date: 2026-05-20
Available data sources: parquet_detections, raw_lightcurve_json, tensor_manifest
Coordinates: RA=286.673, Dec=9.63316
Detections: 147
Non-detections: 674
Filters observed: g, r
First MJD: 58340.3
Last MJD: 61180.4
Time span days: 2840.14
Schema version: 1.12

Classification Metadata

No broker or catalog classification metadata is attached.

Any external labels shown here are metadata only, not Argus conclusions.

Light-Curve Summary

Detections: 147
Non-detections: 674
Filters observed: g, r
First MJD: 58340.3
Last MJD: 61180.4
Time span days: 2840.14
Most recent detection MJD: 61180.4
Longest detection gap days: 938.291

Per-Filter Summary

Filter	Detections	Non-detections	Mag min	Mag max	Delta mag
g	1	130	21.0457	21.0457	0
r	146	526	19.2748	20.3721	1.0973

Feature Summary

Source: light-curve
Band: r
Status: computed
Usable points: 145

Feature Values

amplitude	0.54865
inter_percentile_range_25	0.351097
maximum_slope	502.942
median	19.4947
median_absolute_deviation	0.124377
standard_deviation	0.255895

Feature Quality Notes

maximum_slope is cadence-sensitive: the steepest adjacent pair is separated by 0.7 minute(s). Treat this as a sampling diagnostic, not a robust physical rate.
Minimum adjacent detection spacing is 0.7 minute(s).

Feature Diagnostics

cadence_sensitive_maximum_slope	True
cadence_sensitive_slope_threshold_days	0.05
maximum_slope_pair_delta_mag	0.232862
maximum_slope_pair_delta_time_days	0.000463
maximum_slope_pair_delta_time_minutes	0.66672
maximum_slope_pair_value_mag_per_day	502.942
minimum_delta_time_days	0.0004629
minimum_delta_time_minutes	0.666576

Interpretation: Descriptive light-curve features were computed for r-band detections using the light-curve package. The r-band observed brightness range is wide (1.10 mag). Standardized scatter is high for this detection set (0.26 mag). These features support comparison across objects. The maximum_slope value is cadence-sensitive for this object and should be read with the feature quality notes.
Caveat: Feature values are descriptive summaries only and do not identify the object type.

Evidence Triage Assessment

anomaly_assessment is an evidence triage summary inside this case file. It summarizes available signals for review; it is not an object-identity claim.

Status: available
Score: 10
Label: high

Drivers

147 detections provide a relatively dense local record.
Coverage spans 2840 days, enough to inspect long-baseline behavior.
Both g and r observations are present for cross-band review.
The largest observed per-band magnitude range is wide (1.10 mag).
Median g/r magnitudes differ enough to merit cross-band inspection (1.55 mag).
Standard descriptive light-curve features were computed.
Feature amplitude implies a wide observed range (1.10 mag).
Feature scatter is high for this detection set (0.26 mag).
Gaussian bump fit leaves elevated residual structure (reduced chi-squared about 2.4).
Largest Gaussian residual is 0.81 mag.
Variability texture shows repeated or irregular directional changes.
Variability texture scatter is materially larger than typical reported errors.
Tensor mask diagnostics are available (92% bins masked).

Cautions

maximum_slope is cadence-sensitive: the steepest adjacent pair is separated by 0.7 minute(s). Treat this as a sampling diagnostic, not a robust physical rate.
Minimum adjacent detection spacing is 0.7 minute(s).
Template-family probe is limited: missing_required_context.
Catalog-context status is not_requested; external context remains limited.
This deterministic assessment supports review triage only. It is not a classification, model verdict, or claim about physical identity.

Input Summary

bands_present	["g", "r"]
brightest_to_median_delta_mag	{"g": 0.0, "r": 0.22502650000000202}
cross_survey_context_status	not_requested
data_sources	["parquet_detections", "raw_lightcurve_json", "tensor_manifest"]
dual_band_median_difference_mag	1.54587
feature_summary_status	computed
gaussian_status	fitted_baseline
max_brightest_to_median_delta_mag	0.225027
max_observed_mag_range	1.0973
non_detection_count	674
observation_count	147
per_filter_mag_range	{"g": 0.0, "r": 1.0973000000000006}
sncosmo_template_probe_status	missing_required_context
tensor_flux_medians	{"g": 13.858620643615724, "r": 33.20390701293945}
tensor_frac_bins_masked	0.9175
tensor_manifest_available	True
tensor_observation_counts	{"g": 1, "g_upper_limits": 19, "r": 1, "r_upper_limits": 19}
tensor_total_unmasked_bins	33
time_span_days	2840.14
variability_behavior_hint	repeated_or_irregular
variability_texture_status	computed

Caveat: This deterministic assessment supports review triage only. It is not a classification, model verdict, or claim about physical identity.

Comparison Summary

Not well explained by a single smooth bump

The Gaussian bump comparator fit, but reduced chi-squared is 2.4, so the single smooth bump captures only part of the point-to-point behavior. The variability texture comparator found repeated or irregular directional changes (8 smoothed turn(s)) and the scatter is larger than typical reported errors. Together, these suggest the r-band light curve is more complex than a single clean one-bump event. Coverage appears sparse or uneven, so cadence may affect the comparison.

Caveat: This is not a physical classification. It does not identify the object type, physical cause, or special status.
Recommended next check: Inspect the residual structure and compare against known repeated-variability behavior.

Model Comparisons

Gaussian bump (r-band)

Model type: gaussian_bump
Filter used: r
Status: fitted_baseline

Parameters

amplitude_mag	0.357512
baseline_mag	19.5076
peak_mjd	59702.1
sigma_days	205.354

Fit Metrics

largest_abs_residual	0.813989
largest_residual_mjd	60108.4
mae	0.190765
n_points	146
reduced_chi2	2.35454
residual_mean	0.0715583
residual_std	0.251967
rmse	0.261932

Residual Summary

Coverage is highly uneven (largest gap 938 days vs median gap 0.00 days); fit quality is limited by sparse coverage.
Residual scatter (σ ≈ 0.25 mag) is comparable to the fitted bump amplitude (0.36 mag) — the data is not well described by a single bump.

Interpretation: A single Gaussian bump was fit to the r-band detections. RMSE = 0.26 mag, reduced χ² ≈ 2.4 — the bump shape captures the average behavior but not the point-to-point variability. See residual_summary for where the fit fails.

Variability texture (r-band)

Model type: variability_texture
Filter used: r
Status: computed

Parameters

None recorded.

Fit Metrics

behavior_hint	repeated_or_irregular
local_extrema_count_after_smoothing	8
mag_max	20.3721
mag_median	19.4998
mag_min	19.2748
median_photometric_error_mag	0.12814
n_points	146
observed_mag_range	1.0973
range_to_error_ratio	8.56327
robust_scatter_mag	0.192464
scatter_to_error_ratio	1.50198
sign_change_tolerance_mag	0.0640701
smoothed_sign_changes	8
smoothing_window_points	5
time_span_days	2810.29
variability_materially_larger_than_errors	True

Residual Summary

Observed r-band range: 1.10 mag; robust scatter: 0.19 mag.
After 5-point smoothing, counted 8 local extrema/sign change(s).
Robust scatter is materially larger than the reported errors.

Interpretation: The r-band detections (146 point(s)) span 1.10 mag with robust scatter 0.19 mag. After 5-point smoothing, 8 local extrema/sign change(s) were counted. The scatter is materially larger than the reported photometric errors. The smoothed sequence has multiple meaningful turns, which suggests repeated or irregular brightness changes more than one smooth bump. This is descriptive only: it does not identify an object type, physical cause, or special status.

sncosmo template probe

Model type: sncosmo_template_probe
Filter used: g,r
Status: missing_required_context

Parameters

None recorded.

Fit Metrics

bands_used	["g", "r"]
magnitude_system	ab
missing_context	["redshift"]
model_family	sncosmo_template_family
n_points	147
template_name	hsiao
zeropoint	25

Residual Summary

Redshift is unavailable in the local case-file context.

Interpretation: sncosmo template fitting was not attempted because redshift is unavailable. Argus does not invent redshift for template-family comparisons.

Cross-Survey Context

Status: not_requested
Coordinates: Not available.
Search radius arcsec: Not available.

Sources

No catalog sources recorded.

Interpretation: Cross-survey catalog context was not requested for this run.
Caveat: No external catalog query was performed.

Uncertainty and Recommended Next Checks

Evidence Notes

Object has 147 rb-filtered detection(s) and 674 non-detection(s) on file.
Filters observed: g, r.
Coverage spans MJD 58340.30 to 61180.44 (2840 days).
Most recent detection: MJD 61180.44.
Longest gap between consecutive detections: 938 days.
In g-band: 1 detection(s), magnitude 21.05–21.05 (Δm = 0.00); 130 non-detection(s).
In r-band: 146 detection(s), magnitude 19.27–20.37 (Δm = 1.10); 526 non-detection(s).
No external classification label is attached to this object in local data.

Uncertainty Notes

Cross-survey catalog context is tracked in the cross_survey_context field; default offline runs record not_requested unless the optional lookup is explicitly enabled.
No spectroscopic information is on file.
No forced-photometry follow-up has been requested.
Candidate explanations above are placeholders, not fits, so mismatch magnitudes and goodness-of-fit values are not yet available.
No external classification label is present in local data.

Recommended Next Checks

Run the optional cross-survey context check at RA=286.67280, Dec=9.63316 if network access and optional dependencies are available.
Inspect archival image cutouts at this position and record any nearby source context as external metadata.
Pull ZTF forced photometry in a plus/minus 90-day window around the most recent detection (MJD 61180.44).
Add richer comparator families only when the required context is available, and record their residuals without treating them as object identity.
If the source is still active (last detection within ~60 days), request follow-up spectroscopy.