For a given MomentumArray, calculate the distance every particle is from a centroid location, and return a MaskArray for all of the particles which are within a given radius. If centre is not provided, the transverse momentum weighted centroid will be used.

Parameters:¶

pmu : MomentumArray¶

Four-momenta, \(p_\mu\), of particles in the set.

radius : float¶

Euclidean distance, or Radius \(R\), in the pseudorapidity-azimuth, \(\eta-\phi\), plane from the centroid, beyond which particles will be filtered out.

mask : MaskArray, optional¶

If provided, will apply the mask to the passed pmu, and output MaskArray will have the same length.

centre : tuple[float, float]¶

Pseudorapidity and azimuth coordinates for a user-defined centroid.

Returns:¶

Mask which retains only the particles within radius of the centroid.

Return type:¶

MaskArray