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QA for AuAu@19.6GeV : old (P02ge) vs new (P07id) production

Updated on Thu, 2007-12-06 17:35. Originally created by chajecki on 2007-11-30 17:01.

A. Number of events that passed the following cuts

trigger word cut - (triggerWord==4608) || (triggerWord==4609)
refMult!=0
(V_x=V_y=V_z)!=0

Old (P02ge) Production	New (P07id) Production
173028	175984

B. V_z distribution (after the same cuts as in A.)

The shape of the vertex distribution from new production a little bit different than from the old production. Not sure if it's significant though.

C. Vertex distribution (Vx vs Vy) - (after cuts from A. plus V_z<=30cm)

Old (P02ge) Production	New (P07id) Production

I found that the vertex distribution in x-y plane is shifted by

Old (P02ge) Production - in [cm] (in parentheses - values from a draft AuAu@19.6GeV spectra paper)	New (P07id) Production - in [cm]
<V_x>= - 0.250 (-0.246 ) <V_y>= 0.371 ( 0.378 )	<V_x>= - 0.231 <V_y>= 0.359

I found a little bit different values of <V_x> and <V_y> in old (P02ge) production than Davis' group. Those values are also different in new production however I think it doesn't really matter a lot since we accept all events with x-y vertex within 1cm from the center.

D. Number of events after applying the following cuts

trigger word cut - (triggerWord==4608) || (triggerWord==4609)
refMult!=0
(V_x=V_y=V_z)!=0
|V_z|<=30 cm
(V_x-<V_x>)² + (V_y-<V_y>)² < 1.

Old (P02ge) Production	New (P07id) Production
43335	38280

Even though more events with reconstructed vertex were found in new production,the number of events that passed cuts seen above is larger in the old production. It's mostly because some events from new production have vertex in x-y plane outside the circle with radius 1cm (see fig. in C)

E. Multiplicity distribution

centrality	0-10 %		10-30 %		30-50 %		10-50 %
multiplicity range [based on P02ge]	237-375		117-236		48-116		48-236
production	P02ge	P07id	P02ge	P07id	P02ge	P07id	P02ge	P07id
# of events	5228	3363	8037	5926	11858	10185	19895	16111

Clearly ref. mult is lower in new (P07id) production than in old production (P02ge) so if one wants to use the new production than centrality has to be redefined.

E. Pion PID (plots after trigger and vertex cuts)

bool good = track && ( track->flag() > 0 ) && ( track->pt() > 0.1 ) && ( track->pt() < 1.0 ) && ( fabs(track->nSigmaPion()) <= 2.0 ) && ( fabs(track->nSigmaKaon()) > 2.0 ) && ( fabs(track->nSigmaProton()) > 2.0 ) && ( fabs(track->nSigmaElectron()) > 2.0 ) && ( track->topologyMap().numberOfHits(kTpcId) >= 10 ) && ( track->dca().perp() < 3.0 );