New Physics Results from the FTPC Joern Putschke for the STAR FTPC group
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Transcript of New Physics Results from the FTPC Joern Putschke for the STAR FTPC group
STAR Analysis Meeting
June 5-7, 2003
New Physics ResultsNew Physics Results
from the FTPCfrom the FTPC
Joern Putschke
for the STAR FTPC group
June 2003 Joern Putschke / STAR Analysis Meeting 2
FTPC calibration finshed :-)
Thanks to all who helped us !
Special thanks toJerome, Lidia and Jeff
June 2003 Joern Putschke / STAR Analysis Meeting 3
Outline
• AuAu calibration quality
• Flow news v1 (Aihong)
• AuAu minbias spectra– <pt> vs. centrality– multiplicity FTPC/TPC
• Forward / backward <pt> correlation
• dAu centrality definition
• dAu spectra
• Outlook & toDo– analysis plans– dAu / pp calibration status
June 2003 Joern Putschke / STAR Analysis Meeting 4
AuAu calibration qualityr s
tep [c
m]
hardware sector
uncorrectedcorrected
For more details on calibration look at (under construction) :http://wwwstar.mppmu.mpg.de/ftpc_calibration_page/index.html
Inner cathode shift correction appliedand works with reasonable precision.
Vertex reconstruction with FTPC trackswith respect to TPC vertex :
x,y +- 200 muz +- 0.5 cm
June 2003 Joern Putschke / STAR Analysis Meeting 5
Flow news (v1)
(Aihong Tang)
v1 signal improvedwith final calibrated FTPC AuAu minbiasdataset !
v2 on the way ...
Flow with FTPCs looks very promising !
June 2003 Joern Putschke / STAR Analysis Meeting 6
AuAu minbias pt distribution1/
Nev
ent d
N/(
p t d
p t)
[1/G
eV2 ]
pt [GeV]
AuAu minbias68k (47K)
no corrections
dca<2cm0.1<=pt<13<=y_pion<3.2n_hits>=5|vertex_z|<=25
<pt>west=0.409 GeV<pt>east=0.394 GeV
June 2003 Joern Putschke / STAR Analysis Meeting 7
<pt> vs. centrality
centrality bin
<p t
> [G
eV]
FTPC westFTPC east
Only slight centralitydependence of <pt>for charged hadronsvisible in the FTPCs.
Same behaviour as for pions in the TPC.
June 2003 Joern Putschke / STAR Analysis Meeting 8
Multiplicity FTPC/TPC
FTPC westFTPC east
centrality bin
<dN
/dN
ch>
Nch,FTPC
Nch
ref
,TP
Cdca<2cm0.1<=pt<12.9<=eta<3.5n_hits>=5|vertex_z|<=25
dummy
June 2003 Joern Putschke / STAR Analysis Meeting 9
String fusion modell
June 2003 Joern Putschke / STAR Analysis Meeting 10
Forward / backward <pt> correlation
with string fusion, no resc.
without string fusion, no resc.
AuAu minbias
June 2003 Joern Putschke / STAR Analysis Meeting 11
Impact parameter vs. multiplicity FTPC east
50k dAu minbias Hijing
z-Vertex <= |60| cm
June 2003 Joern Putschke / STAR Analysis Meeting 12
dAu Multiplicity FTPC east
|vertexz| <= 50cm
dca <= 3cm
2.8 <= || < 3.8
nhits >= 5
triggerID cut (minbias)
# primary tracks FTPC east
1/N
even
tsdN
/dN
ch
June 2003 Joern Putschke / STAR Analysis Meeting 13
Multiplicity FTPC east vs. vertex-z
# prim. tracks FTPC east
dca [cm]
Slight Vertex-z dependence of FTPC east multiplicity for vz>30 cm could be explained due to <dca> shift and useddca cut < 3cm to minimize backgroundand fake tracks.
<dca> shift due to missalignement of FTPCs(not calibrated yet) !
June 2003 Joern Putschke / STAR Analysis Meeting 14
run day
perc
ent
of e
vent
sCentrality FTPC east
|vertexz| <= 50cmdca <= 3cm2.8 <= || < 3.8nhits >= 5triggerID cut (minbias)
nch (east) % of events
<=11 40-100
12-17 20-40
>=18 0-20
June 2003 Joern Putschke / STAR Analysis Meeting 15
dAu pt distribution
dAu minbias1.2 M (370K)
no corrections
dca<2cm0.1<=pt<13<=y_pion<3.2n_hits>=5|vertex_z|<=25
<pt>west=0.36 GeV<pt>east=0.367 GeV
1/N
even
t dN
/(p t
dp t
) [1
/GeV
2 ]
pt [GeV]
June 2003 Joern Putschke / STAR Analysis Meeting 16
FTPC east multiplicity neutron tag
minBiaszdcw<=17zdcw>17
# primary tracks FTPC east
1/N
even
tsdN
/dN
ch
June 2003 Joern Putschke / STAR Analysis Meeting 17
dAu pt distribution neutron tag
FTPC east FTPC west
1/N
eve
nt d
N/(
p t d
p t)
[1/G
eV
2]
1/N
eve
nt d
N/(
p t d
p t)
[1/G
eV
2]
pt [GeV] pt [GeV]
<pt>zdcw>17 =0.352 GeV<pt>zdcw<=17=0.369 GeV
<pt>zdcw>17 =0.359 GeV<pt>zdcw<=17=0.360 GeV
dummy
June 2003 Joern Putschke / STAR Analysis Meeting 18
Outlook & toDo
• Analysis plans– AuAu minbias spectra, flow ...
June 2003 Joern Putschke / STAR Analysis Meeting 19
The STAR FTPC group
• Volker Eckardt• Peter Maierbeck• Maria Mora Corral• Markus Oldenburg • Joern Putschke• Janet Seyboth• Peter Seyboth• Frank Simon
June 2003 Joern Putschke / STAR Analysis Meeting 20
FTPC pion acceptance
June 2003 Joern Putschke / STAR Analysis Meeting 21
AuAu efficiency
June 2003 Joern Putschke / STAR Analysis Meeting 22
dAu efficiency
|vertexz| < 20cm