20.13.10 vari_rad_vel_statistics
Statistical parameters of radial velocity time series, using only transits not rejected, see rejected_by_variability column in vari_epoch_radial_velocity.
Note that NaN will be reported when the parameter value is missing or cannot be calculated.
Columns description:
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
A unique single numerical identifier of the source obtained from gaia_source (for a detailed description see gaia_source.source_id).
num_selected_rv : Total number of radial velocity transits selected for variability analysis (short)
The number of processed observations for variability analyses of this source, using only transits not rejected, see rejected_by_variability column in vari_epoch_radial_velocity.
mean_obs_time_rv : Mean observation time for radial velocity transits (double, Time[Barycentric JD in TCB 2 455 197.5 (day)])
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Name: The mean observation time
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Control parameters: None
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Output: Let be a time series of size at times . The mean is defined as
(20.37)
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Name: The time duration of the time series
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Control parameters: None
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Output: Let be a time series of size at times , with to . The time duration of the time series is equal to .
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Name: The minimum value of the time series
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Control parameters: None
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Output: Let be a time series of size at times , with to . The minimum value of the time series is defined as:
(20.38)
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Name: The maximum value of the time series
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Control parameters: None
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Output: Let be a time series of size at times , with to . The maximum value of the time series is defined as:
(20.39)
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Name: The mean of the time series
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Control parameters: None
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Output: Let be a time series of size . The mean is defined as
(20.40)
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Name: The median of the time series
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Control parameters: None
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Output: The 50th percentile unweighted value.
Let be a time series of size ordered such as . The -th (per cent) percentile is defined for as follows:
(20.41)
range_rv : Difference between the highest and lowest radial velocity transits (float, Velocity[km s])
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Name: The range of the time series
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Control parameters: None
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Output: Let be a time series, its largest element, and its smallest element, then the range is defined as
(20.42)
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Name: The square root of the unbiased unweighted variance.
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Output: Let be a time series of size . The unweighted standard deviation is defined as the square root of the sample-size unbiased unweighted variance:
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Name: The standardised unbiased unweighted skewness.
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Output: Let be a time series of size . The sample-size unbiased unweighted skewness moment is defined as:
The standardized unbiased skewness is defined as:
where is the square root of the unbiased unweighted variance around the unweighted mean. While is an unbiased estimate of the population value, becomes unbiased in the limit of large .
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Name: The standardised unbiased unweighted kurtosis.
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Output: Let be a time series of size . The sample-size unbiased unweighted kurtosis cumulant is defined as:
The standardized unbiased kurtosis is defined as:
where is the unbiased unweighted variance around the unweighted mean. While is an unbiased estimate of the population value, becomes unbiased in the limit of large .
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Name: The Median Absolute Deviation (MAD)
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Control parameters: None
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Output: Let be a time series of size . The MAD is defined as the median of the absolute deviations from the median of the data, scaled by a factor of (where is the inverse of the cumulative distribution function for the standard normal distribution), so that the expectation of the scaled MAD at large equals the standard deviation of a normal distribution:
(20.43)
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Name: The Abbe value
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Control parameters: None
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Output: Let be a time-sorted time series of size , such that for all . The Abbe value is defined as
(20.44) where is the unweighted mean.
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Name: The Interquartile Range (IQR)
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Control parameters: None
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Output: The difference between the (unweighted) 75th and 25th percentile values: IQR.
Let be a time series of size ordered such as . The -th (per cent) percentile is defined for as follows:
(20.45)