Multi-hyperons in p-p events X- X+ X(1530)0 X(1530)0 W- W+ Tome Anticic Kreso Kadija Tatjana Susa Vedran Nikolic 1996 1.03 M 1999 1.21 M Rudjer Boskovic Institute Zagreb, Croatia 2000 2.67 M 2001 0.67 M 2002 2.84 M NA49 collaboration meting, Krakow, 2008

Data corrected with millepede Main vertex with improved method X signal 13 parameter fitter 3 MeV/bin Data corrected with millepede Main vertex with improved method about 3800 X- about 1200 X+ tome.anticic@cern.ch

X cuts X cuts X p p all tracks need at least 8 VTPC points Lrap < -1.0 |Lim -1.11567| < 8 MeV (by/0.5)2 + (bx)2 < 12 -1.0 < Lrap < -0.5 |Lim -1.11567| < 12 MeV X -0.5 < Lrap < 0.5 |Lim -1.11567| < 18 MeV (pby/0.2)2 + (pbx/0.4)2 > 0.5 2 0.5 < Lrap |Lim -1.11567| < 20 MeV p proton Xrap < -1.75 zX - zmain < 0 cm -1.75< Xrap < 0.75 zX - zmain < 5 cm p 0.75 < Xrap < 1.25 zX - zmain < 12 cm 1.25 < XXap zX - zmain < 20 cm all tracks need at least 8 VTPC points Spectra with minmal cuts: 5 cm vertex 20 MeV around L mass No impact cuts all tracks are +- 3 s (dE/dX) Rejected spectra due to above cuts tome.anticic@cern.ch

Includes contribution of neutral lambda decay X acceptance Includes contribution of neutral lambda decay tome.anticic@cern.ch

X- signal- rapidity mb mb rapidity pt tome.anticic@cern.ch

X- signal,error and temperature Rapidity Signal (mb) Statistical error Systematic error Temperature (MeV) Error -1.5 0.0160 0.0022 0.0009 -1.0 0.0229 0.0014 0.0004 152 3 -0.5 0.0298 0.0012 0.0006 169 0.0 0.0333 0.0013 0.0005 155 0.5 0.0308 0.0015 170 4 1.0 0.0225 0.0019 5 1.5 0.0145 0.0039 tome.anticic@cern.ch

X- cross section s= 0.090 +- 0.004 mb Venus tome.anticic@cern.ch

X- signal- inv. xf tome.anticic@cern.ch

X- signal- xf tome.anticic@cern.ch

X+ - rapidity mb mb rapidity pt tome.anticic@cern.ch

X+ signal and temperature Rapidity Signal (mb) Statistical error Systematic error Temperature (MeV) Error -1.5 0.00232 0.0012 0.00022 -1.0 0.00611 0.00093 0.00039 -0.5 0.01056 0.00071 0.00016 133 3 0.0 0.01387 0.00078 0.00014 147 4 0.5 0.00950 0.00080 0.00033 129 1.0 0.0056 0.0011 0.0003 tome.anticic@cern.ch

Rapidity- data and Venus X+ – cross section mb s= 0.026 +- 0.002 mb Rapidity- data and Venus Venus tome.anticic@cern.ch

X+ - inv xf mb mb tome.anticic@cern.ch

X+ - xf tome.anticic@cern.ch

Prim track selection: D c2 < 0.5 between ttrack and rtrack X(1530)0 2.5 MeV binning About 550 X(1530)0 selection: +- 6 MeV around Xmass if Xrap < 0.25, +- 20 MeV otherwise Prim track selection: D c2 < 0.5 between ttrack and rtrack tome.anticic@cern.ch

X(1530)0 T = 150 +- 20 tome.anticic@cern.ch

X(1530)0 signal and temperature Rapidity Signal (mb) Statistical error Systematic error -1.0 0.0050 0.0012 0.0005 -0.5 0.0066 0.0010 0.0006 0.0 0.0083 0.5 0.0059 0.0011 1.0 0.0049 0.0015 tome.anticic@cern.ch

X(1530)0 cross section s= 0.020 +- 0.002 mb Venus tome.anticic@cern.ch

X(1530)0 xf and inv. xf Invariant xf xf tome.anticic@cern.ch

Central rapidity only +- 0.25 X(1530)0 Central rapidity only +- 0.25 scentralrap= 0.0020 +- 0.0008 mb tome.anticic@cern.ch

DATA(after all other cuts) W : additional cuts zW - zmain > 12 cm DATA(after all other cuts) MC Rap = -0.5 Ptot of Kaon candidate Ptot of Kaon tome.anticic@cern.ch

Asymetric dedx cut on Kaon (pion main contaminant) W: additional cuts II Asymetric dedx cut on Kaon (pion main contaminant) Rap = -0.5 Rap = 0 Rap = 0.5 tome.anticic@cern.ch

Inv mass W- Rap = -0.5 Rap = 0.0 Rap = 0.5 about 70 W- tome.anticic@cern.ch

W- pt only 1 rap bin, from -1.25 to 1.25 Invariant xf T = 163 +- 4 rapidity tome.anticic@cern.ch

W- -0.5 0.0 0.5 Rapidity Signal (mb) Statistical error Systematic error -0.5 0.00107 0.00048 0.00004 0.0 0.00197 0.00052 0.00003 0.5 0.00132 0.00040 tome.anticic@cern.ch

W- s= 0.0045 +- 0.001 mb Invariant xf Venus tome.anticic@cern.ch

W- inv. Xf and xf Invariant xf xf tome.anticic@cern.ch

W+ scentralrap= 0.00095 + - 0.0004 mb tome.anticic@cern.ch

Things to come Things to be in the next paper: singly strange hyperon paper- L, L(1520), S(1385) What about K*, Ks ? pA also worked on in parallel tome.anticic@cern.ch

L new pt and rapidity acceptance previous rap range up to +- 1.5 pt at midrap previous pt range up to 1.35 GeV pt = 1.5 GeV pt = 1.7 GeV all L pt = 1.9 GeV pt = 2.1 GeV rap = - 2.0 tome.anticic@cern.ch

More hyperons L(1520) tome.anticic@cern.ch

S(1385)+ -> L p+ S(1385)- -> L p- Width ~ 38 MeV

S(1385)+, S(1385)- ~ 4000 ~ 6000 tome.anticic@cern.ch

S(1385)+ _ Rap -1.0 Rap -1.5 Rap -0.5 Rap 0.0 tome.anticic@cern.ch

S(1385)+ _ Rap 0.5 Rap 1.0 Rap 1.5 tome.anticic@cern.ch

S(1385)+/- counts, ratios (NO ERRORS, NO MC CORRECTION FACTOR) -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5 rapidity tome.anticic@cern.ch

S(1385)+ pt 0.1 0.3 0.5 0.9 1.1 0.7 tome.anticic@cern.ch

S(1385)+ pt 1.3 1.5 tome.anticic@cern.ch

S(1385)+ , S(1385)- tome.anticic@cern.ch

Backup slides tome.anticic@cern.ch

Omega II DATA MC Impact of Omega Impact of Kaon (Wby/0.5)2 + (Wbx)2 < 12 Impact of Kaon (Kby/0.2)2 + (Kbx/0.4)2 > 0.5 2 tome.anticic@cern.ch

Inv mass W- Rap = 0.0 Rap = -1.0 Rap = 0.5 Rap = -0.5 Rap = 1.0 tome.anticic@cern.ch

Omega/AntiOmega cuts (same) DATA MC Rap = -1 Rap = -0.5 Ptot of Kaon tome.anticic@cern.ch

Inv mass W+ tome.anticic@cern.ch

X spectra in the 1999 data set new X- old X- tome.anticic@cern.ch

aomega tome.anticic@cern.ch

Experimental data using Gap TPC S4 trigger effect Min bias Venus events Experimental data using Gap TPC tome.anticic@cern.ch

X reconstruction correction factors improved R3D/main vertex/ X finder/ geometry standard R3D/main vertex/ X finder/ geometry The correction factors include the loss due to neutral L decays, as well as the loss due to 18 cm cut from the 20 cm target tome.anticic@cern.ch

New residuals, new impact parameters new L forward rap. (1999 data) Impact parameter in x Impact parameter in y old L forward rap. tome.anticic@cern.ch

Cross section determination weight = gTriggerCS(year)*nMcOrig/nMcRec/nPPEvents nPPEvents=nFullEvents*(1.-rateEmpty/rateFull) tome.anticic@cern.ch

Gauss main vertex fit R3D main vertex accuracy Gauss main vertex accuracy R3D main vertex accuracy vs track number Comparison Gauss main vertex accuracy vs track number Gauss significantly better Mean closer to zero RMS better by 30 % Much smaller tails