Acts::Experimental::GbtsGraphBuilder::Config Struct Reference

Config for the prompt graph. More...

#include <Acts/Seeding/GbtsGraphBuilder.hpp>

Public Attributes
bool	calibrateStrips = true
	Resolve a doublet's strip endpoints against its own direction before cutting on them.
float	curvatureSplitAbsTau = 4.0f
	|cot(theta)| separating the two curvature cuts, corresponding to |eta| of about 2.1.
float	cutDCurvMax = 0.001f
	Maximum allowed curvature tolerance for candidate edge connections.
float	cutDPhiMax = 0.012f
	Maximum difference in allowed tangent between candidate edge connections.
float	d0Max = 3.0f * Acts::UnitConstants::mm
	Maximum d0 impact parameter when validating an edge-connection triplet.
bool	doubletFilterRZ = true
	Apply RZ cuts on doublets.
bool	matchBeforeCreate = false
	Match seeds before creating them.
std::int32_t	matchBeforeCreateMaxBarrelOrder = 1
	Highest pixel barrel layer, counted inside out, to which matchBeforeCreate applies when it is enabled.
std::uint32_t	matchBeforeCreateMaxEdges = 2
	Incoming edge count below which a node is accepted without a tau match.
float	maxAbsTau = 36.0f
	Largest |cot(theta)| accepted for a doublet.
float	maxCurvatureHighEta = 4.75e-4f / Acts::UnitConstants::mm
	Maximum |curvature| above curvatureSplitAbsTau, before that scaling.
float	maxCurvatureLowEta = 3.75e-4f / Acts::UnitConstants::mm
	Maximum |curvature| below curvatureSplitAbsTau, before that scaling.
float	maxEdgesPerSP = 30.0f
	Maximum number of GBTS edges/doublets per space point.
float	maxOuterRadius = 550.0f
	Maximum radius of the pixel detector.
float	maxStripLengthFraction = 1.1f
	How far along a strip a crossing may land and still be recovered, as a multiple of the strip half-length, so 1 is the strip itself.
float	maxZ0 = 600.0f
	Maximum z0 value. In pixel mode the value is picked from the RoI.
float	minDeltaRadius = 2.0f * Acts::UnitConstants::mm
	Minimum delta radius between layers.
float	minPt = 1.0f * Acts::UnitConstants::GeV
	Minimum transverse momentum.
float	minZ0 = -600.0f
	Minimum z0 value. In pixel mode the value is picked from the RoI.
float	phiWindowFarOffset = 0.015f
	Phi window above phiWindowSplitDeltaRadius, in the same form.
float	phiWindowFarSlope = 2.2e-4f / Acts::UnitConstants::mm
	Slope of the far phi window per unit radial separation.
float	phiWindowNearOffset = 0.002f
	Phi window below phiWindowSplitDeltaRadius, as an offset plus a slope times the radial separation.
float	phiWindowNearSlope = 4.33e-4f / Acts::UnitConstants::mm
	Slope of the near phi window per unit radial separation.
float	phiWindowSplitDeltaRadius = 60.0f * Acts::UnitConstants::mm
	Radial separation splitting the two phi-window slopes below.
float	sumRatioCutMax = 1.3f
	Threshold of the summed ratios, between 1 (only one difference can use its full cut) and 3 (no effect beyond the individual cuts).
float	tauRatioCut = 0.007f
	Tau ratio scale of the validateTriplets high-pT check.
float	tauRatioPrecut = 0.009f
	Tau ratio precut threshold.
float	tripletPtFraction = 0.8f
	Fraction of minPt a triplet may fall to, allowing for three-point pT resolution.
float	tuningPt = 0.9f * Acts::UnitConstants::GeV
	pT at which the default cut coefficients were tuned; they scale by tuningPt / minPt.
bool	useEtaBinning = true
	Use eta binning from geometry structure.
bool	useSumRatioCut = false
	Reject a candidate edge connection whose tau ratio, phi and curvature differences, each divided by its own cut, add up to more than sumRatioCutMax: a pair that is marginal in all three at once.
bool	validateTriplets = true
	Optional validation for barrel triplets.
std::int32_t	z0HistogramMaxBarrelOrder = 0
	Highest pixel barrel layer, counted inside out, whose nodes are cut against the z0 histogram of their outer neighbourhood and whose isolated nodes are skipped.
float	z0Resolution = 2.5f * Acts::UnitConstants::mm
	Half-width of the z0 window against which a node is matched in the histogram.

Detailed Description

Config for the prompt graph.

Member Data Documentation

calibrateStrips

bool Acts::Experimental::GbtsGraphBuilder::Config::calibrateStrips = true

Resolve a doublet's strip endpoints against its own direction before cutting on them.

Nothing is written back; the correction belongs to the pair.

matchBeforeCreateMaxBarrelOrder

std::int32_t Acts::Experimental::GbtsGraphBuilder::Config::matchBeforeCreateMaxBarrelOrder = 1

Highest pixel barrel layer, counted inside out, to which matchBeforeCreate applies when it is enabled.

A negative value disables it.

maxAbsTau

float Acts::Experimental::GbtsGraphBuilder::Config::maxAbsTau = 36.0f

Largest |cot(theta)| accepted for a doublet.

The default corresponds to |eta| of about 4.3, beyond the acceptance of any current tracker.

maxStripLengthFraction

float Acts::Experimental::GbtsGraphBuilder::Config::maxStripLengthFraction = 1.1f

How far along a strip a crossing may land and still be recovered, as a multiple of the strip half-length, so 1 is the strip itself.

This is the same quantity as TripletSeedFinder::Config::toleranceParam.

phiWindowFarSlope

float Acts::Experimental::GbtsGraphBuilder::Config::phiWindowFarSlope = 2.2e-4f / Acts::UnitConstants::mm

Slope of the far phi window per unit radial separation.

Scaled by tuningPt / minPt.

phiWindowNearSlope

float Acts::Experimental::GbtsGraphBuilder::Config::phiWindowNearSlope = 4.33e-4f / Acts::UnitConstants::mm

Slope of the near phi window per unit radial separation.

Scaled by tuningPt / minPt.

tauRatioCut

float Acts::Experimental::GbtsGraphBuilder::Config::tauRatioCut = 0.007f

Tau ratio scale of the validateTriplets high-pT check.

The linking cut comes from the layer pairs, see GbtsLayerConnection.

z0HistogramMaxBarrelOrder

std::int32_t Acts::Experimental::GbtsGraphBuilder::Config::z0HistogramMaxBarrelOrder = 0

Highest pixel barrel layer, counted inside out, whose nodes are cut against the z0 histogram of their outer neighbourhood and whose isolated nodes are skipped.

A negative value disables the cut.