20.13.8 vari_eclipsing_binary

This table describes the properties of the eclipsing binaries resulting from the variability analysis.

Columns description:

solution_id : Solution Identifier (long)

All Gaia data processed by the Data Processing and Analysis Consortium comes tagged with a solution identifier. This is a numeric field attached to each table row that can be used to unequivocally identify the version of all the subsystems that were used in the generation of the data as well as the input data used. It is mainly for internal DPAC use but is included in the published data releases to enable end users to examine the provenance of processed data products. To decode a given solution ID visit https://gaia.esac.esa.int/decoder/solnDecoder.jsp

source_id : Unique source identifier (long)

A unique single numerical identifier of the source obtained from gaia_source (for a detailed description see gaia_source.source_id).

global_ranking : Number between 0 (worst) and 1 (best) (float)

Number between 0 (worst) and 1 (best), based on the fraction of variance unexplained (FVU) for the geometrical model fit.

reference_time : Reference time used for the geometric model fit (double, Time[Barycentric JD in TCB $-$ 2 455 197.5 (day)])

Time with respect to which the phases of the gaussian components refer in the geometrical model, or of the cosine(s) if no gaussian component is present in the model.

frequency : Frequency of geometric model of the eclipsing binary light curve (double, Frequency[day${}^{-1}$])

Frequency of geometric model of the eclipsing binary light curve.

frequency_error : Uncertainty of frequency (float, Frequency[day${}^{-1}$])

Uncertainty of frequency.

geom_model_reference_level : Magnitude reference level of geometric model (float, Magnitude[mag])

Magnitude reference level of geometric model.

geom_model_reference_level_error : Uncertainty of geom_model_reference_level (float, Magnitude[mag])

Uncertainty of geom_model_reference_level.

geom_model_gaussian1_phase : Phase of the Gaussian 1 component (float)

Phase with respect to reference_time. NaN if no Gaussian component in the model. Note: Gaussian1 does not necessarily correspond to the deepest eclipse.

geom_model_gaussian1_phase_error : Uncertainty of geom_model_gaussian1_phase (float)

Uncertainty of geom_model_gaussian1_phase.

geom_model_gaussian1_sigma : Standard deviation [phase] of Gaussian 1 component (float)

NaN if no Gaussian component in the model. Note: Gaussian1 does not necessarily correspond to the deepest eclipse.

geom_model_gaussian1_sigma_error : Uncertainty of geom_model_gaussian1_sigma (float)

Uncertainty of geom_model_gaussian1_sigma.

geom_model_gaussian1_depth : Magnitude depth of Gaussian 1 component (float, Magnitude[mag])

NaN if no Gaussian component in the model. Note: Gaussian1 does not necessarily correspond to the deepest eclipse.

geom_model_gaussian1_depth_error : Uncertainty of geom_model_gaussian1_depth (float, Magnitude[mag])

Uncertainty of geom_model_gaussian1_depth. It can be null when the model could not derive it.

geom_model_gaussian2_phase : Phase of Gaussian 2 component (float)

Phase with respect to reference_time. NaN if no second Gaussian component in the model

geom_model_gaussian2_phase_error : Uncertainty of geom_model_gaussian2_phase (float)

Uncertainty of geom_model_gaussian2_phase.

geom_model_gaussian2_sigma : Standard deviation [phase] of Gaussian 2 component (float)

NaN if no second Gaussian component in the model

geom_model_gaussian2_sigma_error : Uncertainty of geom_model_gaussian2_sigma (float)

Uncertainty of geom_model_gaussian2_sigma.

geom_model_gaussian2_depth : Magnitude depth of Gaussian2 component (float, Magnitude[mag])

NaN if no second Gaussian component in the model

geom_model_gaussian2_depth_error : Uncertainty of geom_model_gaussian2_depth (float, Magnitude[mag])

Uncertainty of geom_model_gaussian2_depth. It can be null when the model could not derive it.

geom_model_cosine_half_period_amplitude : Amplitude of the cosine component with half the period of the geometric model (float, Magnitude[mag])

The amplitude is half peak-to-peak. NaN if no cosine component with half the period of the geometric model.

geom_model_cosine_half_period_amplitude_error : Uncertainty of geom_model_cosine_half_period_amplitude (float, Magnitude[mag])

Uncertainty of geom_model_cosine_half_period_amplitude.

geom_model_cosine_half_period_phase : Reference phase of the cosine component with half the period of the geometric model (float)

Phase with respect to reference_time. When model contains Gaussian(s) this phase is equal to either geom_model_gaussian1_phase or geom_model_gaussian2_phase. NaN if no cosine component with half the period of the geometric model.

geom_model_cosine_half_period_phase_error : Uncertainty of geom_model_cosine_half_period_phase (float)

When model contains Gaussian(s) this uncertainty is the same as either geom_model_gaussian1_phase_error or geom_model_gaussian2_phase_error.

model_type : Type of geometrical model of the light curve (string)

Type of eclipsing binary geometric model of the G-band light curve. For each model the frequency and geom_model_reference_level as well as their uncertainties (_error) are set. The additional fields (and their uncertainty) that are available for each model_type are specified below:

• •

  ONEGAUSSIAN
  Geometric model parameters defined:

  • –

    geom_model_gaussian1_phase

  • –

    geom_model_gaussian1_sigma

  • –

    geom_model_gaussian1_depth

  Derived parameters defined:

  • –

    derived_primary_ecl_phase

  • –

    derived_primary_ecl_duration

  • –

    derived_primary_ecl_depth

• •

  ONEGAUSSIAN_WITH_ELLIPSOIDAL
  Geometric model parameters defined:

  • –

    geom_model_gaussian1_phase

  • –

    geom_model_gaussian1_sigma

  • –

    geom_model_gaussian1_depth

  • –

    geom_model_cosine_half_period_amplitude

  • –

    geom_model_cosine_half_period_phase

  Derived parameters defined:

  • –

    derived_primary_ecl_phase

  • –

    derived_primary_ecl_duration

  • –

    derived_primary_ecl_depth

• •

  TWOGAUSSIANS
  Geometric model parameters defined:

  • –

    geom_model_gaussian1_phase

  • –

    geom_model_gaussian1_sigma

  • –

    geom_model_gaussian1_depth

  • –

    geom_model_gaussian2_phase

  • –

    geom_model_gaussian2_sigma

  • –

    geom_model_gaussian2_depth

  Derived parameters defined:

  • –

    derived_primary_ecl_phase

  • –

    derived_primary_ecl_duration

  • –

    derived_primary_ecl_depth

  • –

    derived_secondary_ecl_phase

  • –

    derived_secondary_ecl_duration

  • –

    derived_secondary_ecl_depth

• •

  TWOGAUSSIANS_WITH_ELLIPSOIDAL_ON_ECLIPSE1
  In this model geom_model_cosine_half_period_phase is the same as geom_model_gaussian1_phase. Geometric model parameters defined:

  • –

    geom_model_gaussian1_phase

  • –

    geom_model_gaussian1_sigma

  • –

    geom_model_gaussian1_depth

  • –

    geom_model_gaussian2_phase

  • –

    geom_model_gaussian2_sigma

  • –

    geom_model_gaussian2_depth

  • –

    geom_model_cosine_half_period_amplitude

  • –

    geom_model_cosine_half_period_phase

  Derived parameters defined:

  • –

    derived_primary_ecl_phase

  • –

    derived_primary_ecl_duration

  • –

    derived_primary_ecl_depth

  • –

    derived_secondary_ecl_phase

  • –

    derived_secondary_ecl_duration

  • –

    derived_secondary_ecl_depth

• •

  TWOGAUSSIANS_WITH_ELLIPSOIDAL_ON_ECLIPSE2
  In this model geom_model_cosine_half_period_phase is the same as geom_model_gaussian2_phase. Geometric model parameters defined:

  • –

    geom_model_gaussian1_phase

  • –

    geom_model_gaussian1_sigma

  • –

    geom_model_gaussian1_depth

  • –

    geom_model_gaussian2_phase

  • –

    geom_model_gaussian2_sigma

  • –

    geomModelGaussian2Fepth

  • –

    geom_model_cosine_half_period_amplitude

  • –

    geom_model_cosine_half_period_phase

  Derived parameters defined:

  • –

    derived_primary_ecl_phase

  • –

    derived_primary_ecl_duration

  • –

    derived_primary_ecl_depth

  • –

    derived_secondary_ecl_phase

  • –

    derived_secondary_ecl_duration

  • –

    derived_secondary_ecl_depth

• •

  ELLIPSOIDAL
  Geometric model parameters defined:

  • –

    geom_model_cosine_half_period_amplitude

  • –

    geom_model_cosine_half_period_phase

num_model_parameters : Number of free parameters of the geometric model (byte)

The number of parameters fitted for each model type. For each model the frequency and geom_model_reference_level are fitted, as well as the geometeric model parameters listed in the detailed description of model_type.

reduced_chi2 : Reduced Chi2 of the geometrical model fit (float)

The reduced Chi-square: ${\chi }^2/\nu$ computed over all observations, where $\nu$ is the number of degrees of freedom.

Note that for high signal to noise observations (i.e. small uncertainties), the reduced Chi-square will increase when the simple geometric model cannot sufficiently model the more complex true light curve shape. A low Chi-square is therefore not a good measure for eclipsing binary detection on itself.

derived_primary_ecl_phase : Primary eclipse: phase at geometrically deepest point (float)

Phase with respect to reference_time. This value is derived from the geometrical model. It can be offset from geom_model_gaussian1_phase or geom_model_gaussian2_phase if a cosine component is present. NaN if no Gaussian component in the geometric model.

derived_primary_ecl_phase_error : Primary eclipse: uncertainty of derived_primary_ecl_phase (float)

Primary eclipse: uncertainty of derived_primary_ecl_phase estimated by a Jackknife resampling method.

derived_primary_ecl_duration : Primary eclipse: duration [phase fraction] (float)

This value is derived from the geometrical model, taking the Gaussian width estimated at a depth of 2% of the Gaussian, with an upper limit of 0.4. NaN if no Gaussian component in the geometric model.

derived_primary_ecl_duration_error : Primary eclipse: uncertainty of derived_primary_ecl_duration (float)

Primary eclipse: uncertainty of derived_primary_ecl_duration. Uncertainties are derived by a Jackknife resampling method. In rare instances, the uncertainty can be artificially larger than 1.

derived_primary_ecl_depth : Primary eclipse: depth (float, Magnitude[mag])

This value is derived from the geometrical model. NaN if no Gaussian component in the geometric model.

derived_primary_ecl_depth_error : Primary eclipse: uncertainty of derived_primary_ecl_depth (float, Magnitude[mag])

Primary eclipse: uncertainty of derived_primary_ecl_depth estimated by a Jackknife resampling method. It can be null when the model could not derive it.

derived_secondary_ecl_phase : Secondary eclipse: phase at geometrically second deepest point (float)

This value is derived from the geometrical model. It can be offset from geom_model_gaussian1_phase or geom_model_gaussian2_phase if a cosine component is present. NaN if no secondary Gaussian component in the geometric model.

derived_secondary_ecl_phase_error : Secondary eclipse: uncertainty of derived_secondary_ecl_phase (float)

Secondary eclipse: uncertainty of derived_secondary_ecl_phase estimated by a Jackknife resampling method.

derived_secondary_ecl_duration : Secondary eclipse: duration [phase fraction] (float)

This value is derived from the geometrical model, taking the Gaussian width estimated at a depth of 2% of the Gaussian, with an upper limit of 0.4. NaN if no secondary Gaussian component in the geometric model.

derived_secondary_ecl_duration_error : Secondary eclipse: uncertainty of derived_secondary_ecl_duration (float)

Secondary eclipse: uncertainty of derived_secondary_ecl_duration. Uncertainties are derived by a Jackknife resampling method. In rare instances, the uncertainty can be artificially larger than 1.

derived_secondary_ecl_depth : Secondary eclipse: depth (float, Magnitude[mag])

This value is derived from the geometrical model. NaN if no secondary Gaussian component in the geometric model.

derived_secondary_ecl_depth_error : Secondary eclipse: uncertainty of derived_secondary_ecl_depth (float, Magnitude[mag])

Secondary eclipse: uncertainty of derived_secondary_ecl_depth estimated by a Jackknife resampling method. It can be null when the model could not derive it.