Double differential K+cross sections have been measured in p+C collisions at 1.2, 1.5 and 2.5 GeV beam energy and in p+Pb collisions at 1.2 and 1.5 GeV. The K+ spectrum taken at 2.5 GeV can be reproduced quantitatively by a model calculation which takes into account first chance proton-nucleon collisions and internal momentum with energy distribution of nucleons according to the spectral function. At 1.2 and 1.5 GeV beam energy the K+ data excess significantly the model predictions for first chance collisions. When taking secondary processes into account the results of the calculations are in much better agreement with the data.
Measurements of the invariant cross sections for the reaction p(400 GeV)+(Li6, Be,C,Al,Cu,Ta)→(π±, K±)+X at laboratory angles from 70° to 160° are reported. Upper limits for p¯ production are given. Comparisons of the data are made using several scaling variables. NUCLEAR REACTIONS Inclusive cross section; 400 GeV incident protons; Li6, Be, C, Al, Cu, Ta targets; production of π, K, and p¯; lab angles 70° to 160°.
No description provided.
No description provided.
No description provided.
The production of K^+ mesons in pA (A = D, C, Cu, Ag, Au) collisions has been investigated at the COoler SYnchrotron COSY-Julich for beam energies T_p = 1.0 - 2.3 GeV. Double differential inclusive pC cross sections at forward angles theta < 12 degrees as well as the target-mass dependence of the K^+ momentum spectra have been measured with the ANKE spectrometer. Far below the free NN threshold at T_{NN}=1.58 GeV the spectra reveal a high degree of collectivity in the target nucleus. From the target-mass dependence of the cross sections at higher energies, the repulsive in-medium potential of K^+ mesons can be deduced. Using pN cross-section parameterisations from literature and our measured pD data we derive a cross-section ratio of sigma(pn -> K^+ X) / sigma(pp -> K^+ X) ~ (3-4).
Double differential cross section for P C --> K+ X obtained in the 1.3 T mode. Errors do not include systematic uncertainties.
Double differential cross section for P C --> K+ X obtained in the 1.6 T mode. Errors do not include systematic uncertainties.
Cross section ratios CU/C and AU/C measured with the 1.3 T mode. Errors include statistical and systematic uncertainties.
The production of the Lambda and Sigma0 hyperons has been measured via the pp->pK+Lambda / Sigma0 reaction at the internal COSY-11 facility in the excess energy range between 14 and 60 MeV. The transition of the Lambda/Sigma0 cross section ratio from about 28 at Q<=13 MeV to the high energy level of about 2.5 is covered by the data showing a strong decrease of the ratio between 10 and 20 MeV excess energy. Effects from the final state interactions in the p-Sigma0 channel seem to be much smaller compared to the p-Lambda one. Estimates of the effective range parameters are given for the N-Lambda and the N-Sigma systems.
Cross section for LAMBDA production.. Statistical errors only.
Cross section for SIGMA0 production.. Statistical errors only.
Energy dependence of the LAMBDA/SIGMA0 ratio.
We report on a measurement of the differential cross sections of inclusive$K^{\pm}_{890}$production in$\sigma^-, pi^-$and ne
The production cross sections for K*+- per nucleus and per nucleon for the SIGMA- beam.
The production cross sections for K*+- per nucleus and per nucleon for the PI- beam.
The production cross sections for K*+- per nucleus and per nucleon for the NEUTRON- beam.
The differential cross sections of the combined elastic and break-up K − d reaction have been measured at 1.21, 1.42 and 2.61 GeV/ c incident K − momentum. The measurements have been performed at the CERN PS using multiwire proportional chambers. The values of the invariant momentum transfer t explored (0.0005<| t |<0.1 GeV 2 ) include the Coulomb-nuclear interference region. The differential cross sections have been analysed in the framework of the Glauber impact-parameter formalism. The observed interference effects have been used to derive the ratio of the real to imaginary part of the forward K − n nuclear amplitude.
SUM OF COHERENT AND BREAK-UP SCATTERING.
SUM OF COHERENT AND BREAK-UP SCATTERING.
SUM OF COHERENT AND BREAK-UP SCATTERING.
The production of Λ,\(\bar \Lambda\) andKs0 has been studied in 200 GeV/nucleonp+S and S+S collisions in the streamer chamber of the NA35 experiment at the CERN SPS. Significant enhancement of the multiplicities of all observed strange particles relative to negative hadrons was observed in central S+S collisions, as compared top+p andp+S collisions. The latter collisions show no overall (relative) strangeness enhancement overp+p, but the rapidity distributions and hadron multiplicities indicate some secondary cascading production of Λ particles in thep+S andp+Au collisions. The Λ polarization in central S+S collisions was found to be compatible with zero up topT=2 GeV/c.
Tranverse kinetic energy spectra of neutral strange particles in P SU collisions.
Tranverse kinetic energy spectra of neutral strange particles in P SU collisions.
Tranverse kinetic energy spectra of neutral strange particles in SU SU collisions.
The production of neutral strange particlesKso, Λ and\(\bar \Lambda \) has been studied in 60 and 200 GeV per nucleon OAu and pAu collisions with the streamer chamber vertex spectrometer of the NA35 experiment at the CERN-SPS accelerator. Ratios of neutral strange particle production to negatively charged particle production in selected regions of phase space were measured to be the same in OAu and pAu reactions. The rates of strange particle production in central OAu collisions are about a factor of 16 higher than in pAu collisions when compared in the same regions of phase space. If an enhancement of strange particle production in OAu collisions relative to pAu collisions is considered to be a signature for quark-gluon plasma formation, no evidence supporting it is observed. The experimental results are compared to the Lund FRITIOF model.
Data requested from authors.
Mid-rapidity open charm spectra from direct reconstruction of $D^{0}$($\bar{D^0}$)$\to K^{\mp}\pi^{\pm}$ in d+Au collisions and indirect electron/positron measurements via charm semileptonic decays in p+p and d+Au collisions at \srt = 200 GeV are reported. The $D^{0}$($\bar{D^0}$) spectrum covers a transverse momentum ($p_T$) range of 0.1 $<p_T<$ 3 \GeVc whereas the electron spectra cover a range of 1 $<p_T<$ 4 GeV/$c$. The electron spectra show approximate binary collision scaling between p+p and d+Au collisions. From these two independent analyses, the differential cross section per nucleon-nucleon binary interaction at mid-rapidity for open charm production from d+Au collisions at RHIC is $d\sigma^{NN}_{c\bar{c}}/dy$=0.30$\pm$0.04 (stat.)$\pm$0.09(syst.) mb. The results are compared to theoretical calculations. Implications for charmoniumm results in A+A collisions are discussed.
Inclusive electrons yield versus transverse momentum in D+AU collisions Data points at PT = 2.2, 2.7 and 3.5 GeV/c was obtained using only the TPC (Time Projection Chamber) and cover a pseudo-rapidity range of -1<eta<1, while other points were obtained using both a prototypeTime-of-Flight System and the TPC and cover a pseudo-rapidity range of -1<eta<0.
Inclusive electrons yield versus transverse momentum in P+P collisions.
D0 yield versus transverse momentum in D+AU collisions.
Transverse momentum distributions and yields for $\pi^{\pm}$, $K^{\pm}$, $p$ and $\bar{p}$ in $p+p$ collisions at $\sqrt{s}$=200 and 62.4 GeV at midrapidity are measured by the PHENIX experiment at the Relativistic Heavy Ion Collider (RHIC). These data provide important baseline spectra for comparisons with identified particle spectra in heavy ion collisions at RHIC. We present the inverse slope parameter $T_{\rm inv}$, mean transverse momentum $<p_T>$ and yield per unit rapidity $dN/dy$ at each energy, and compare them to other measurements at different $\sqrt{s}$ in $p+p$ and $p+\bar{p}$ collisions. We also present the scaling properties such as $m_T$ scaling, $x_T$ scaling on the $p_T$ spectra between different energies. To discuss the mechanism of the particle production in $p+p$ collisions, the measured spectra are compared to next-to-leading-order or next-to-leading-logarithmic perturbative quantum chromodynamics calculations.
Invariant cross sections for inclusive PI+ and PI- production in P P collisions at a centre-of-mass energy of 200 GeV. There is an additional normalization uncertainty of 9.7 PCT.
Invariant cross sections for inclusive K+ and K- production in P P collisions at a centre-of-mass energy of 200 GeV. There is an additional normalization uncertainty of 9.7 PCT.
Invariant cross sections for inclusive P and PBAR production in P P collisions at a centre-of-mass energy of 200 GeV with feed-down weak decay corrections NOT applied. There is an additional normalization uncertainty of 9.7 PCT.
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