Argus Case File: ZTF18abbdazk

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

Evidence Narrative

Mixed evidence with cautious interpretation

The Gaussian bump comparator fit, but reduced chi-squared is 2.2, so the single smooth bump captures only part of the point-to-point behavior. The variability texture comparator found changes that are comparable to the reported photometric errors. Together, these suggest the r-band detections are not fully captured by one smooth bump.

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 2.2).
Variability texture measurement_level
The measured changes are comparable to reported photometric errors.
Standard feature summary computed
Descriptive light-curve features were computed from 13 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.
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.
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: ZTF18abbdazk
Source date: 2026-05-20
Available data sources: parquet_detections, raw_lightcurve_json, tensor_manifest
Coordinates: RA=286.629, Dec=1.94183
Detections: 19
Non-detections: 201
Filters observed: g, r
First MJD: 58283.4
Last MJD: 61180.4
Time span days: 2897.04
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: 19
Non-detections: 201
Filters observed: g, r
First MJD: 58283.4
Last MJD: 61180.4
Time span days: 2897.04
Most recent detection MJD: 61180.4
Longest detection gap days: 623.14

Per-Filter Summary

Filter	Detections	Non-detections	Mag min	Mag max	Delta mag
g	5	82	19.9722	20.156	0.183842
r	13	98	18.3986	18.8844	0.485804

Feature Summary

Source: light-curve
Band: r
Status: computed
Usable points: 13

Feature Values

amplitude	0.242902
inter_percentile_range_25	0.26614
maximum_slope	37.6421
median	18.5573
median_absolute_deviation	0.104815
standard_deviation	0.16469

Feature Quality Notes

maximum_slope is cadence-sensitive: the steepest adjacent pair is separated by 3.6 minute(s). Treat this as a sampling diagnostic, not a robust physical rate.
Minimum adjacent detection spacing is 3.6 minute(s).

Feature Diagnostics

cadence_sensitive_maximum_slope	True
cadence_sensitive_slope_threshold_days	0.05
maximum_slope_pair_delta_mag	0.094542
maximum_slope_pair_delta_time_days	0.0025116
maximum_slope_pair_delta_time_minutes	3.6167
maximum_slope_pair_value_mag_per_day	37.6421
minimum_delta_time_days	0.0025116
minimum_delta_time_minutes	3.6167

Interpretation: Descriptive light-curve features were computed for r-band detections using the light-curve package. The r-band observed brightness range is moderate (0.49 mag). Standardized scatter is moderate for this detection set (0.16 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: 8
Label: high

Drivers

19 detections provide a usable local record.
Coverage spans 2897 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 moderate (0.49 mag).
Median g/r magnitudes differ enough to merit cross-band inspection (1.52 mag).
Standard descriptive light-curve features were computed.
Gaussian bump fit leaves elevated residual structure (reduced chi-squared about 2.2).
Tensor mask diagnostics are available (89% bins masked).

Cautions

maximum_slope is cadence-sensitive: the steepest adjacent pair is separated by 3.6 minute(s). Treat this as a sampling diagnostic, not a robust physical rate.
Minimum adjacent detection spacing is 3.6 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": 0.10847099999999799, "r": 0.15868000000000038}
cross_survey_context_status	not_requested
data_sources	["parquet_detections", "raw_lightcurve_json", "tensor_manifest"]
dual_band_median_difference_mag	1.52337
feature_summary_status	computed
gaussian_status	fitted_baseline
max_brightest_to_median_delta_mag	0.15868
max_observed_mag_range	0.485804
non_detection_count	201
observation_count	19
per_filter_mag_range	{"g": 0.1838419999999985, "r": 0.4858039999999981}
sncosmo_template_probe_status	missing_required_context
tensor_flux_medians	{"g": 0.0, "r": 127.14203643798828}
tensor_frac_bins_masked	0.89
tensor_manifest_available	True
tensor_observation_counts	{"g": 0, "g_upper_limits": 28, "r": 2, "r_upper_limits": 20}
tensor_total_unmasked_bins	44
time_span_days	2897.04
variability_behavior_hint	flat_or_measurement_level
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

Single smooth bump leaves residual structure

Caveat: This is not a physical classification. It does not identify the object type, physical cause, or special status.
Recommended next check: Inspect the largest residuals and review cadence gaps before adding richer comparators.

Model Comparisons

Gaussian bump (r-band)

Model type: gaussian_bump
Filter used: r
Status: fitted_baseline

Parameters

amplitude_mag	-857.877
baseline_mag	876.434
peak_mjd	60200.9
sigma_days	86854.9

Fit Metrics

largest_abs_residual	0.327377
largest_residual_mjd	60193.3
mae	0.111401
n_points	13
reduced_chi2	2.2375
residual_mean	0.00625633
residual_std	0.143152
rmse	0.143288

Residual Summary

No striking residual structure relative to the fit.

Interpretation: A single Gaussian bump was fit to the r-band detections. RMSE = 0.14 mag, reduced χ² ≈ 2.2 — 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	flat_or_measurement_level
local_extrema_count_after_smoothing	3
mag_max	18.8844
mag_median	18.5573
mag_min	18.3986
median_photometric_error_mag	0.121953
n_points	13
observed_mag_range	0.485804
range_to_error_ratio	3.98354
robust_scatter_mag	0.155399
scatter_to_error_ratio	1.27425
sign_change_tolerance_mag	0.0609765
smoothed_sign_changes	3
smoothing_window_points	3
time_span_days	2747.36
variability_materially_larger_than_errors	False

Residual Summary

Observed r-band range: 0.49 mag; robust scatter: 0.16 mag.
After 3-point smoothing, counted 3 local extrema/sign change(s).
Robust scatter is comparable to the reported errors.

Interpretation: The r-band detections (13 point(s)) span 0.49 mag with robust scatter 0.16 mag. After 3-point smoothing, 3 local extrema/sign change(s) were counted. The scatter is comparable to the reported photometric errors. The measured changes are small relative to the reported errors, so this check treats the sequence as measurement-level or nearly flat. 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	18
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 19 rb-filtered detection(s) and 201 non-detection(s) on file.
Filters observed: g, r.
Coverage spans MJD 58283.40 to 61180.44 (2897 days).
Most recent detection: MJD 61180.44.
Longest gap between consecutive detections: 623 days.
In g-band: 5 detection(s), magnitude 19.97–20.16 (Δm = 0.18); 82 non-detection(s).
In r-band: 13 detection(s), magnitude 18.40–18.88 (Δm = 0.49); 98 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=286.62936, Dec=1.94183 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.