Planck 2013 results. I. Overview of products and scientific results

Peer reviewe

Planck intermediate results X : Physics of the hot gas in the Coma cluster

Peer reviewe

Planck Intermediate Results II: Comparison of Sunyaev–Zeldovich measurements from Planck and from the Arcminute Microkelvin Imager for 11 galaxy clusters

A comparison is presented of Sunyaev–Zeldovich measurements for 11 galaxy clusters as obtained by Planck and by the ground-based interferom- eter, the Arcminute Microkelvin Imager. Assuming a universal spherically-symmetric Generalised Navarro, Frenk & White (GNFW) model for the cluster gas pressure profile, we jointly constrain the integrated Compton-Y parameter (Y500) and the scale radius (θ500) of each cluster. Our resulting constraints in the Y500 − θ500 2D parameter space derived from the two instruments overlap significantly for eight of the clusters, although, overall, there is a tendency for AMI to find the Sunyaev–Zeldovich signal to be smaller in angular size and fainter than Planck. Significant discrepancies exist for the three remaining clusters in the sample, namely A1413, A1914, and the newly-discovered Planck cluster PLCKESZ G139.59+24.18. The robustness of the analysis of both the Planck and AMI data is demonstrated through the use of detailed simulations, which also discount confusion from residual point (radio) sources and from diffuse astrophysical foregrounds as possible explanations for the discrepancies found. For a subset of our cluster sample, we have investigated the dependence of our results on the assumed pressure profile by repeating the analysis adopting the best-fitting GNFW profile shape which best matches X-ray observations. Adopting the best-fitting profile shape from the X-ray data does not, in general, resolve the discrepancies found in this subset of five clusters. Though based on a small sample, our results suggest that the adopted GNFW model may not be sufficiently flexible to describe clusters universally

Hypertriton Production in p-Pb Collisions at √sNN = 5.02 TeV

The study of nuclei and antinuclei production has proven to be a powerful tool to investigate the formation mechanism of loosely bound states in high-energy hadronic collisions. The first measurement of the production of ${\rm ^{3}_{\Lambda}\rm H}$ in p-Pb collisions at $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV is presented in this Letter. Its production yield measured in the rapidity interval -1 < y < 0 for the 40% highest multiplicity p-Pb collisions is ${\rm d} N /{\rm d} y =[\mathrm{6.3 \pm 1.8 (stat.) \pm 1.2 (syst.) ] \times 10^{-7}}$. The measurement is compared with the expectations of statistical hadronisation and coalescence models, which describe the nucleosynthesis in hadronic collisions. These two models predict very different yields of the hypertriton in small collision systems such as p-Pb and therefore the measurement of ${\rm d} N /{\rm d} y$ is crucial to distinguish between them. The precision of this measurement leads to the exclusion with a significance larger than 6$\sigma$ of some configurations of the statistical hadronisation, thus constraining the production mechanism of loosely bound states

Characterizing the initial conditions of heavy-ion collisions at the LHC with mean transverse momentum and anisotropic flow correlations

Correlations between mean transverse momentum and anisotropic flow coefficients or are measured as a function of centrality in Pb–Pb and Xe–Xe collisions at sqrt(sNN) = 5.02 TeV and 5.44 TeV, respectively, with ALICE. In addition, the recently proposed higher-order correlation between [pt], v2, and v3 is measured for the first time, which shows an anticorrelation for the presented centrality ranges. These measurements are compared with hydrodynamic calculations using IP-Glasma and TRENTO initial-state shapes, the former based on the Color Glass Condensate effective theory with gluon saturation, and the latter a parameterized model with nucleons as the relevant degrees of freedom. The data are better described by the IP-Glasma rather than the TRENTO based calculations. In particular, Trajectum and JETSCAPE predictions, both based on the TRENTO initial state model but with different parameter settings, fail to describe the measurements. As the correlations between [pt] and vn are mainly driven by the correlations of the size and the shape of the system in the initial state, these new studies pave a novel way to characterize the initial state and help pin down the uncertainty of the extracted properties of the quark–gluon plasma recreated in relativistic heavy-ion collisions

General balance functions of identified charged hadron pairs of (pi,K,p) in Pb-Pb collisions at 2.76 TeV

First measurements of balance functions (BFs) of all combinations of identified charged hadron ( π , K, p) pairs in Pb–Pb collisions at √sNN = 2.76 TeV recorded by the ALICE detector are presented. The BF measurements are carried out as two-dimensional differential correlators versus the relative rapidity (delta-y) and azimuthal angle (delta-φ) of hadron pairs, and studied as a function of collision centrality. The delta-φ dependence of BFs is expected to be sensitive to the light quark diffusivity in the quark–gluon plasma. While the BF azimuthal widths of all pairs substantially decrease from peripheral to central collisions, the longitudinal widths exhibit mixed behaviors: BFs of π π and cross-species pairs narrow significantly in more central collisions, whereas those of KK and pp are found to be independent of collision centrality. This dichotomy is qualitatively consistent with the presence of strong radial flow effects and the existence of two stages of quark production in relativistic heavy-ion collisions. Finally, the first measurements of the collision centrality evolution of BF integrals are presented, with the observation that charge balancing fractions are nearly independent of collision centrality in Pb–Pb collisions. Overall, the results presented provide new and challenging constraints for theoretical models of hadron production and transport in relativistic heavy-ion collisions

K∗(892)0 and φ(1020) production in p-Pb collisions at √s NN = 8.16 TeV

The production of K*(892)(0) and phi(1020) resonances has been measured in p-Pb collisions at root s(NN) = 8.16 TeV using the ALICE detector. Resonances are reconstructed via their hadronic decay channels in the rapidity interval -0.5 8 GeV/c), the R-pPb values of all hadrons are consistent with unity within uncertainties. The R-pPb of K*(892)(0) and phi(1020) at root s(NN) = 8.16 and 5.02 TeV show no significant energy dependence

The histology of ovarian cancer: worldwide distribution and implications for international survival comparisons (CONCORD-2)

Objective Ovarian cancers comprise several histologically distinct tumour groups with widely different prognosis. We aimed to describe the worldwide distribution of ovarian cancer histology and to understand what role this may play in international variation in survival. Methods The CONCORD programme is the largest population-based study of global trends in cancer survival. Data on 681,759 women diagnosed during 1995â\u80\u932009 with cancer of the ovary, fallopian tube, peritoneum and retroperitonum in 51 countries were included. We categorised ovarian tumours into six histological groups, and explored the worldwide distribution of histology. Results During 2005â\u80\u932009, type II epithelial tumours were the most common. The proportion was much higher in Oceania (73.1%), North America (73.0%) and Europe (72.6%) than in Central and South America (65.7%) and Asia (56.1%). By contrast, type I epithelial tumours were more common in Asia (32.5%), compared with only 19.4% in North America. From 1995 to 2009, the proportion of type II epithelial tumours increased from 68.6% to 71.1%, while the proportion of type I epithelial tumours fell from 23.8% to 21.2%. The proportions of germ cell tumours, sex cord-stromal tumours, other specific non-epithelial tumours and tumours of non-specific morphology all remained stable over time. Conclusions The distribution of ovarian cancer histology varies widely worldwide. Type I epithelial, germ cell and sex cord-stromal tumours are generally associated with higher survival than type II tumours, so the proportion of these tumours may influence survival estimates for all ovarian cancers combined. The distribution of histological groups should be considered when comparing survival between countries and regions