Image Parameters

This page lists the image parameters available in ctapipe. These definitions are pulled directly from the source code, ensuring they are always up to date.

Hillas Parameters

class ctapipe.containers.HillasParametersContainer(prefix=None, **fields)

Hillas Parameters in a spherical system centered on the pointing position (TelescopeFrame). The cog position is given as offset in longitude and latitude in degree.

Attributes:

intensityField(default=nan)

Total integrated charge (often called ‘size’)

skewnessField(default=nan)

Longitudinal asymmetry of the image

kurtosisField(default=nan)

measure of the longitudinal tailedness of the charges distribution (following Pearson’s definition: equals 3.0 for a normal distribution)

fov_lonField(default=nan deg, unit=deg)

Centroid longitude angle in a spherical system centered on the pointing position

fov_latField(default=nan deg, unit=deg)

Centroid latitude angle in a spherical system centered on the pointing position

rField(default=nan deg, unit=deg)

Radial coordinate of the centroid

phiField(default=nan deg, unit=deg)

Polar coordinate of the centroid

lengthField(default=nan deg, unit=deg)

standard deviation along the major-axis

length_uncertaintyField(default=nan deg, unit=deg)

uncertainty of length

widthField(default=nan deg, unit=deg)

standard spread along the minor-axis

width_uncertaintyField(default=nan deg, unit=deg)

uncertainty of width

psiField(default=nan deg, unit=deg)

Orientation (angle) of major axis relative to X-axis

psi_uncertaintyField(default=nan deg, unit=deg)

uncertainty of psi

transverse_cog_uncertaintyField(default=nan deg, unit=deg)

uncertainty on the centroid along the transverse axis of the image

metadict

dict of attached metadata

prefixstr

Prefix attached to column names when saved to a table or file

Timing Parameters

class ctapipe.containers.TimingParametersContainer(prefix=None, **fields)

Slope and Intercept of a linear regression of the arrival times along the shower main axis in a spherical system centered on the pointing position (TelescopeFrame)

Attributes:

interceptField(default=nan)

Arrival time at the COG (longitudinal = 0)

deviationField(default=nan)

Temporal dispersion around the linear model (RMSE)

slopeField(default=nan 1 / deg, unit=1 / deg)

Time gradient along the main shower axis (1/deg)

metadict

dict of attached metadata

prefixstr

Prefix attached to column names when saved to a table or file

Leakage Parameters

class ctapipe.containers.LeakageContainer(prefix=None, **fields)

Fraction of signal in 1 or 2-pixel width border from the edge of the camera, measured in number of signal pixels or in intensity.

Attributes:

pixels_width_1Field(default=nan)

fraction of pixels after cleaning that are in camera border of width=1

pixels_width_2Field(default=nan)

fraction of pixels after cleaning that are in camera border of width=2

intensity_width_1Field(default=nan)

Intensity in photo-electrons after cleaning that are in the camera border of width=1 pixel

intensity_width_2Field(default=nan)

Intensity in photo-electrons after cleaning that are in the camera border of width=2 pixels

metadict

dict of attached metadata

prefixstr

Prefix attached to column names when saved to a table or file

Concentration Parameters

class ctapipe.containers.ConcentrationContainer(prefix=None, **fields)

Concentrations are ratios between light amount in certain areas of the image and the full image.

Attributes:

cogField(default=nan)

Fraction of light within 1 pixel diameter of the COG

coreField(default=nan)

Fraction of light within the 1-sigma Hillas ellipse boundary

pixelField(default=nan)

Fraction of light in the brightest pixel

metadict

dict of attached metadata

prefixstr

Prefix attached to column names when saved to a table or file

Morphology Parameters

class ctapipe.containers.MorphologyContainer(prefix=None, **fields)

Parameters related to pixels surviving image cleaning

Attributes:

n_pixelsField(default=-1)

Number of pixels surviving cleaning

n_islandsField(default=-1)

Number of distinct pixel clusters (connected components)

n_small_islandsField(default=-1)

Number of islands with size <= 2 pixels

n_medium_islandsField(default=-1)

Number of islands with 3 <= size <= 50 pixels

n_large_islandsField(default=-1)

Number of islands with size > 50 pixels

metadict

dict of attached metadata

prefixstr

Prefix attached to column names when saved to a table or file

Intensity Statistics

class ctapipe.containers.IntensityStatisticsContainer(prefix=None, **fields)

Attributes:

maxField(default=nan)

Value of pixel with maximum intensity

minField(default=nan)

Value of pixel with minimum intensity

meanField(default=nan)

Mean intensity of pixels in the image

stdField(default=nan)

standard deviation of intensity of pixels in the image

skewnessField(default=nan)

Fisher skewness measuring the asymmetry of the intensity distribution)

kurtosisField(default=nan)

Fisher kurtosis measuring the tailedness of the intensity distribution (equals 0.0 for a normal distribution)

metadict

dict of attached metadata

prefixstr

Prefix attached to column names when saved to a table or file

Peak Time Statistics

class ctapipe.containers.PeakTimeStatisticsContainer(prefix=None, **fields)

Attributes:

maxField(default=nan)

Value of pixel with maximum intensity

minField(default=nan)

Value of pixel with minimum intensity

meanField(default=nan)

Mean intensity of pixels in the image

stdField(default=nan)

standard deviation of intensity of pixels in the image

skewnessField(default=nan)

Fisher skewness measuring the asymmetry of the intensity distribution)

kurtosisField(default=nan)

Fisher kurtosis measuring the tailedness of the intensity distribution (equals 0.0 for a normal distribution)

metadict

dict of attached metadata

prefixstr

Prefix attached to column names when saved to a table or file

Core Parameters

class ctapipe.containers.CoreParametersContainer(prefix=None, **fields)

Telescope-wise shower’s direction in the Tilted/Ground Frame

Attributes:

psiField(default=nan deg, unit=deg)

Orientation of major axis in the Tilted/Ground Frame

metadict

dict of attached metadata

prefixstr

Prefix attached to column names when saved to a table or file