change # Time-stamp: "1-October-2000"
Hadident task home page
This page collects the information on the hadron identification
task i.e. pion, kaon and proton identification with the ionization loss
measured in the TPC or the vertex detector and the Cherenkov photons detected
in the RICHes. If you want to contribute, in case of problems or questions
You can access here the dE/dx
home page. It contains information on the software and the use of the
dE/dx for physics analysis purposes.
RICH and dE/dx
NEW! 183 GeV data: a plot for the dE/dx and RICHes used in the search for
heavy long-lived sleptons.
The analysis is extended to heavy long-lived squarks.
A plot for the dE/dx and RICHes used in the search
for heavy particles at 172 GeV can be found here.
A note - updated for the 94C processing -
is available on the RICH, TPC and combined RICH/TPC tags, with examples
and a description of the tagging commons, efficiencies and comparison of
data and simulation for the 94C2 processing.
The status of the new processing 94C can be found in
for the 94C combined dE/dx and RICH heavy particle tag is available. The
upper part shows the number of tagged events vs the momentum in data and
simulation. The green area corresponds to the pions in the sample. The
lower plot gives the efficiency vs the momentum: blue points for the protons,
red for the kaons and green for the pions. A plot for the mean Cherenkov
angle in the BRICH gas radiator (94C) for high momentum tracks above 7
GeV/c before and after a heavy TPC tag, shows clearly the proton
and kaon bands.
NEW! RICH plots for the 1997 data can be found for the 183 GeV
data , and a plot of the mass squared distibution for
kaons in the BRICH and FRICH.
Two DELPHI notes give a description of the reconstruction algorithm RIBMEAN
DELPHI 96-133 RICH 90 - updated for the 94C data - and of the tagging routine
DELPHI 96-103 RICH 89. Both notes give extensive information, examples
and comparison of data and simulation (measured misidentification rates,
efficiencies etc.) for the 94B3 processing.
the 94C2 data and simulation for RIBMEAN: the Cherenkov angle and number
of photons for both RICHes. The scanned transparencies of the talk on the
performance and improvements of the RICHes in 94C can be found on the DELPHI
A small note
has been written for user who want to use RIBMEAN tagging routines for
high efficiency kaon or proton tagging. It is explained how similar efficiencies
and purities as HADSIGN can be reached.
Some RICH results for the 1996 data can be found for the hadronic
data period 2, and a plot of the mass squared distibution for Z and
172 GeV data showing kaons.
To get started, read the user guide of the hadident/rich software:
(14-Jun-1996). Examples and instructions can also be found in the dstana
writeup and in the DELPHI notes on RIBMEAN and NEWTAG and the note
Some news items are in the status1.ps
You can find some RICH colour plots 94C for fast
kaons and for the liquid
radiator. More hadron identification plots can be found in figures.
Plots and notes were made in summer 1995, using the 94B2 processing. They
are obsolete both for RIBMEAN and HADSIGN, but you can still find them
Users can find information about
based on 94B2.
The new rich fullDST format
Other information on the RICH, as e.g. physics publications, can be found
on the DELPHI