JOPSS - Search Results

Journal Articles

Identified charged hadron production in collisions at = 200 and 62.4 GeV

Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Yasuyuki*; Al-Bataineh, H.*; Alexander, J.*; Aoki, Kazuya*; Aphecetche, L.*; Armendariz, R.*; et al.

Physical Review C, 83(6), p.064903_1 - 064903_29, 2011/06

https://doi.org/10.1103/PhysRevC.83.064903

Times Cited Count：184 Percentile：99.44(Physics, Nuclear)

Transverse momentum distributions and yields for $pi^{pm}, K^{pm}, p$ , and in collisions at = 200 and 62.4 GeV at midrapidity are measured by the PHENIX experiment at the RHIC. We present the inverse slope parameter, mean transverse momentum, and yield per unit rapidity at each energy, and compare them to other measurements at different collisions. We also present the scaling properties such as and scaling and discuss the mechanism of the particle production in collisions. The measured spectra are compared to next-to-leading order perturbative QCD calculations.

Journal Articles

Azimuthal correlations of electrons from heavy-flavor decay with hadrons in and Au+Au collisions at $sqrt{s_{NN}}$ = 200 GeV

Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Yasuyuki*; Al-Bataineh, H.*; Alexander, J.*; Aoki, Kazuya*; Aphecetche, L.*; Aramaki, Y.*; et al.

Physical Review C, 83(4), p.044912_1 - 044912_16, 2011/04

https://doi.org/10.1103/PhysRevC.83.044912

Times Cited Count：8 Percentile：49.7(Physics, Nuclear)

Measurements of electrons from the decay of open-heavy-flavor mesons have shown that the yields are suppressed in Au+Au collisions compared to expectations from binary-scaled collisions. Here we extend these studies to two particle correlations where one particle is an electron from the decay of a heavy flavor meson and the other is a charged hadron from either the decay of the heavy meson or from jet fragmentation. These measurements provide more detailed information about the interaction between heavy quarks and the quark-gluon matter. We find the away-side-jet shape and yield to be modified in Au+Au collisions compared to collisions.

Journal Articles

The Upper pliocene diatom zone and fission-track age of the upper Koetoi Formation around the Sarobetsu anticline, northern Hokkaido

Yasue, Kenichi; Akiba, Fumio*; Ohira, Hiroto*; Ishii, Eiichi

Chishitsugaku Zasshi, 112(4), p.284 - 293, 2006/04

https://doi.org/10.5575/geosoc.112.284

The Upper Pliocene Neodenticula koizumii Zone was recognized near the boundary between the Koetoi and Yuchi Formations in the western part of the Horonobe area, northern Hokkaido. In previous studies, numerous reworked fossil diatoms from underlying strata have obscured the recognition of the zone. However, this study samples include commonly both N. seminae and N. koizumii as probable autochthonous diatoms and almost no reworked fossil diatoms. Therefore, the samples belong obviously to the Neodenticula koizumii Zone. In addition, fission track ages of zircon crystals from a tuff between the diatom samples show 2.20.1 Ma and 2.30.1 Ma (2.50.1 Ma:). The diatoms and FT age data indicate that the depositional age around the boundary between the Koetoi and Yuchi Formations in the study area is 2.1-2.4 Ma. The age is younger than that in the eastern part of the Horonobe area for about one million years, which is concordant with the previously suggested westward migration of the Tenpoku Basin after Pliocene.