uc l - ex / 0 20 90 12 v 1 1 7 Se p 20 02 Sub - threshold φ - meson yield in central 58 Ni + 58 Ni collisions
نویسندگان
چکیده
The φ-meson production cross section is measured for the first time at a subthreshold energy of 1.93 AGeV in Ni+Ni central collisions. The φ data were obtained within the acceptance of the CDC/Barrel subsystem of FOPI. For a sample of 4.7 · 10 central events, after background subtraction, 23 candidates were observed. Extensive GEANT simulations of the detector performance are shown in a thorough comparison to the real response, aiming at a good understanding of the apparatus and at a trustable determination of the efficiencies, production probability and possible systematic errors. A filter procedure is elaborated, which is meant to facilitate the comparison of any theoretical calculation with the data. How to extrapolate the present value to a φ-meson cross section in 4π is also discussed. This result on pseudo-vector mesons can now be compared to existing experimental knowledge for the same reaction at the same incident energy for various outgoing channels, K and K included. A significant fraction (at least 20%) of the Kmesons is originating in the decay of the φ, supporting the statement that the two channels are strongly correlated.
منابع مشابه
ar X iv : n uc l - ex / 0 20 90 28 v 1 2 8 Se p 20 02 1 φ meson production in Au - Au collisions at √ s NN = 200 GeV
متن کامل
2 00 2 Sub - threshold φ - meson yield in central 58 Ni + 58 Ni collisions
The φ-meson production cross section is measured for the first time at a subthreshold energy of 1.93 AGeV in Ni+Ni central collisions. The φ data were obtained within the acceptance of the CDC/Barrel subsystem of FOPI. For a sample of 4.7 · 10 central events, after background subtraction, 23 candidates were observed. Extensive GEANT simulations of the detector performance are shown in a thoroug...
متن کاملuc l - ex / 0 20 90 29 v 1 2 8 Se p 20 02 1 Charged Hadron Spectra in PHENIX
PHENIX has measured transverse momentum spectra of charged particles at mid-rapidity up to 10 GeV/c in Au+Au collisions at √ s nn = 200 GeV. For central collisions, the yield at high p T is significantly suppressed comparing to binary scaled p+p data, and this suppression is stronger than observed at 130 GeV [1,2]. Above 4 GeV/c, the deficit of high momentum particles is almost independent of p...
متن کاملar X iv : n uc l - ex / 0 60 90 20 v 1 1 4 Se p 20 06 φ meson production and partonic collectivity
New results on φ-meson production and elliptic flow v 2 measurements from RHIC 2004 run (Run-IV) have been reviewed. In addition, the di-hadron correlation function between the trigged φ and Ω and the associated soft particles was simulated. Knowledge about these results are discussed.
متن کاملar X iv : n uc l - ex / 0 20 90 30 v 1 2 9 Se p 20 02 1 High p T identified hadron ratios in √ s NN = 200 GeV Au + Au Collisions
The PHENIX detector at RHIC measured high p T identified hadron ratios in √ s N N = 200 GeV Au+Au collisions. Within the current systematic and statistical errors, p/p ratios that are measured up to 3.8 GeV/c are almost independent of both p T and centrality. The baryon to meson ratio is measured through p/π and p/π ratios up to 3.8 GeV/c, showing they are strongly centrality dependent.
متن کامل