Fri·Aug 19, 2011Friday·August 19, 2011

1. 01*

   The puzzle of anomalously large isospin violations in $\eta (1405/1475)\to 3\pi$

   Jia-Jun Wu🇨🇳 · Xiao-Hai Liu🇨🇳 · Qiang Zhao🇨🇳 · Bing-Song Zou🇨🇳

   The BES-III Collaboration recently report the observation of anomalously large isospin violations in $J/\psi \to \gamma \eta (1405/1475)\to \gamma {\pi }^0{f}_0(980)\to \gamma +3\pi$, where the $f_0(980)$ in the $\pi \pi$ invariant mass spectrum appears to be much narrower ($\sim$ 10 MeV) than the peak width ($\sim$50 MeV) measured in other processes. We show that a mechanism, named as triangle singularity (TS), can produce a narrow enhancement between the charged and neutral $K\bar{K}$ thresholds, i.e., $2m_{K^{\pm }}\sim 2m_{K^0}$. It can also lead to different invariant mass spectra for $\eta (1405/1475)\to a_0(980)\pi$ and $K{\bar{K}}^{\ast }+c.c.$, which can possibly explain the long-standing puzzle about the need for two close states $\eta (1405)$ and $\eta (1475)$ in $\eta \pi \pi$ and $K\bar{K}\pi$, respectively. The TS could be a key to our understanding of the nature of $\eta (1405/1475)$ and advance our knowledge about the mixing between $a_0(980)$ and $f_0(980)$.

   ↳ hep-phhep-exnucl-exnucl-thPRL(2012)·188 citations
2. 02*

   J/Psi production at forward rapidity in Pb-Pb collisions at sqrt(s_NN) = 2.76 TeV, measured with the ALICE detector

   P. Pillot (for the ALICE Collaboration)🇫🇷

   In the ALICE experiment, at forward rapidity (2.5 < y < 4), the production of heavy quarkonium states is measured via their mu+ mu- decay channels. We present the first measurement of inclusive J/Psi production, down to pT = 0, from Pb-Pb data collected at the LHC at sqrt(s_NN) = 2.76 TeV. Preliminary results on the nuclear modification factor (R_AA) and the central to peripheral nuclear modification factor (R_CP) show J/Psi suppression with no significant centrality dependence and an integrated R_AA(0-80%) = 0.49 \pm 0.03(stat.) \pm 0.11(syst.).

   ↳ hep-exnucl-exJ.Phys.G(2011)·41 citations
3. 03*

   Pionic Supergiant Radiohalos as Integral Record of Pion Emission During Nuclear Fission

   D. B. Ion (1 and 3)🇷🇴 · Reveica Ion-Mihai (2)🇷🇴 · M. L. Ion (2) ((1) Institute for Physics and Nuclear Engineering, IFIN-HH, Bucharest Romania, (2) Bucharest University, Faculty of Physics, Bucharest, Romania, (3) Academy of Romanian Scientists)🇷🇴

   In this paper we presented a short review of radioactive halos as from the perspective of their interpretation as integral record in time of different kind of known or unknown radioactivities. A special attention is paid for the unified interpretation of the supergiant halos (SGH), discovered by Grady, Walker and Laemlein, as integral record of pion emission during fission.

   ↳ nucl-thnucl-ex0 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.