| 1. |
- Aggarwal, MM, et al.
(författare)
-
Centrality dependence of charged-neutral particle fluctuations in 158A (GeVPb)-Pb-208+Pb-208 collisions
- 2003
-
Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 67:4
-
Tidskriftsartikel (refereegranskat)abstract
- Results on the study of localized fluctuations in the multiplicity of charged particles and photons produced in 158A GeV/c Pb+Pb collisions are presented for varying centralities. The charged versus neutral particle multiplicity correlations in common phase space regions of varying azimuthal sizes are analyzed by two different methods. Various types of mixed events are constructed to probe fluctuations arising from different sources. The measured results are compared to those from simulations and from mixed events. The comparison indicates the presence of nonstatistical fluctuations in both the charged particle and photon multiplicities in limited azimuthal regions. However, no correlated charged-neutral fluctuations, a possible signature of formation of disoriented chiral condensates, are observed. An upper limit on the production of disoriented chiral condensates is set.
|
|
| 2. |
- Aggarwal, MM, et al.
(författare)
-
Event-by-event fluctuations in particle multiplicities and transverse energy produced in 158A GeVPb plus Pb collisions
- 2002
-
Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 65:5
-
Tidskriftsartikel (refereegranskat)abstract
- Event-by-event fluctuations in the multiplicities of charged particles and photons, and the total transverse energy in 158A GeV Pb+Pb collisions are studied for a wide range of centralities. For narrow centrality bins the multiplicity and transverse energy distributions are found to be near perfect Gaussians. The effect of detector acceptance on the multiplicity fluctuations has been studied and demonstrated to follow statistical considerations. The centrality dependence of the charged particle multiplicity fluctuations in the measured data has been found to agree reasonably well with those obtained from a participant model. However, for photons the multiplicity fluctuations have been found to be lower compared to those obtained from a participant model. The multiplicity and transverse energy fluctuations have also been compared to those obtained from the VENUS event generator.
|
|
| 3. |
|
|
| 4. |
- Aggarwal, MM, et al.
(författare)
-
Transverse mass distributions of neutral pions from Pb-208-induced reactions at 158 center dot A GeV
- 2002
-
Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 23:2, s. 225-236
-
Tidskriftsartikel (refereegranskat)abstract
- Results on transverse mass spectra of neutral pious measured at central rapidity are presented for impact parameter selected 158-A GeV Pb + Pb-1 and Pb + Nb collisions. The distributions cover the range 0.5 GeV/c(2) less than or equal to MT - Mo less than or equal to 4 GeV/c(2). The change of the spectral shape and the multiplicity with centrality is studied in detail. In going from p+p to semi-peripheral Pb+Pb collisions there is a nuclear enhancement increasing with transverse mass similar to the well known Cronin effect, while for very central collisions this enhancement appears to be weaker than expected.
|
|
| 5. |
- Andreoiu, Corina, et al.
(författare)
-
Yrast Superdeformed Band in 59Cu
- 2000
-
Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 62:5, s. 513011-513015
-
Tidskriftsartikel (refereegranskat)abstract
- High-spin states in 59Cu were populated using the fusion-evaporation reactions 28Si+40Ca at a beam energy of 125 MeV and 36Ar+28Si at a beam energy of 143 MeV. The Gammasphere array in conjunction with ancillary detector systems allowed for the identification of a superdeformed rotational band in 59Cu, which was firmly linked to low-spin yrast states. Using directional correlations of oriented states, a spin-parity assignment of Iπ = 25/2+ to the band head was possible. The average quadrupole moment of the band is measured to be Qt = (2.24±0.40) e b. The characteristics of the band are compared to neighboring nuclei and predictions of different mean-field theories.
|
|
| 6. |
|
|
| 7. |
|
|
| 8. |
|
|
| 9. |
- Christensen, Torben, et al.
(författare)
-
Factors controlling large scale variations in methane emissions from wetlands
- 2003
-
Ingår i: Geophysical Research Letters. - 0094-8276 .- 1944-8007. ; 30:7
-
Tidskriftsartikel (refereegranskat)abstract
- [1] Global wetlands are, at estimate ranging 115-237 Tg CH4/yr, the largest single atmospheric source of the greenhouse gas methane (CH4). We present a dataset on CH4 flux rates totaling 12 measurement years at sites from Greenland, Iceland, Scandinavia and Siberia. We find that temperature and microbial substrate availability (expressed as the organic acid concentration in peat water) combined explain almost 100% of the variations in mean annual CH4 emissions. The temperature sensitivity of the CH4 emissions shown suggests a feedback mechanism on climate change that could validate incorporation in further developments of global circulation models.
|
|
| 10. |
|
|
