Core (or COG) Fit¶
I3TopRecoCore
calculates a Shower core, using the sqrts of the pulse
amplitude as weights and calculating the COG of these. If no Pulses
are available, it can also be run with Hits, but then no sqrt is
used and the result is worse (no equal distribution between the
tanks).
datareadout [string, DEFAULT=”ITSimData”] Name of the input Pulses from the data to be used
showercore [string, DEFAULT=”ShowerCOG”] Name of the output I3Particle
ntanks [DEFAULT=all of them] Number of highest-charge tanks to use
weighting_power [DEFAULT=0.5] power for the weighting - the weight will be PE^power
verbose [bool, DEFAULT=false]
Plane Wave Fit¶
I3TopRecoPlane
calculates what plane wave fits the shower front best. Therefore it calculates the minimum of this:
The fit parameters are the average time \(T_0\) and the shower direction, represented by u and v. Using the COG of the x and y in that weights (\(w_i=1/\sigma^2\)), \(T_0\) decouples from the other parameters and they all can be calculated easily from the matrix of their linear system. The \(\sigma\) is set to 5 ns for all pulses equally as a rough approximation.
The calculation goes through 2 iterations. In between, a correction for the different tank heights is applied.
datareadout [string, DEFAULT=”ITSimData”] Name of the input Pulses from the data to be used
showerplane [string, DEFAULT=”ShowerPlane”] Name of the output I3Particle
trigger [int, DEFAULT=3] Set a software trigger on how many stations required in the input Pulses.
EventHeaderName [DEFAULT=”IceTopEventHeader”] Event header name
verbose [bool, DEFAULT=false]