dN/dEta analysis can be done in 2 ways:

1) For single centrality bin:
Using AliTrackletTaskUni.{h,cxx} steered by the
runAAF.C and MyAnalysisMacro.C

It will produce a file with 3D (sparse) histos "delta" vs Zv vs eta
where delta is either "weigted distance" and/or "dphi - bend", which is used
both the match the tails and to define the signal cut.
The exact value of cut can be decided at the stage of processing the histos,
so different signal and tail matching thresholds can be tested 

Note that wide Zv eta range can be processed and then restricted at 
the correction stage.

One has to run runAAF.C for over the data and MC datasets and then analyse them
using the CorrectSpectra.C macro (the cuts/variables use... must be set 
beforehand)


2) Mor multiple centrality bins at once:
AliTrackletTaskMulti.{h,cxx} steered by the 
runAAFMulti.C and MyAnalysisMacroTrackletMulti.C

It produces for each centrality bin a set of histos, particularly 2D histos for
Zv vs eta with the signal cut on "distance" already applied (by defaults one for 
"w.dist" another for "dphi-bend" + 1D histo of "distance" for selected Zv,eta
range (to be used for the bg matching the tails of data"

Note: Zv, eta ranges must be defined at data processing stage, as well as the 
signal cut (cutSigNStd in the runAAFMulti) and number of st.dev to keep (nStdDev)

One has to runAAFMulti.C for over the data and MC datasets and then analyse them
using the CorrectSpectraMulti.C macro 

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Both methods can use 3 types of generated bg: injection, rotation and mixing.
Simultaneous eployment of all these methods is also possible, but may create 
a memory problem.

The corresponding CorrectSpectra... macros must be tuned for the bg.type used.