proteses para cabelo

The European Physical Journal C, 2012

Eur Phys J C, 2011

The nature of the X(3872) enhancement is analyzed in the framework of the Resonance-Spectrum Expansion, by studying it as a regular J PC =1++ charmonium state, though strongly influenced and shifted by open-charm decay channels. The observed but Okubo-Zweig-Iizuka-forbidden ρ 0 J/ ψ and ωJ/ ψ channels are coupled as well, but effectively smeared out by using complex ρ 0 and ω masses, in order to account for their physical widths, followed by a rigorous algebraic procedure to restore unitarity. A very delicate interplay between the D 0 D ∗0, ρ 0 J/ ψ, and ωJ/ ψ channels is observed. The data clearly suggest that the X(3872) is a very narrow axial-vector cbar{c} resonance, with a pole at or slightly below the D 0 D ∗0 threshold.

Physical review letters, 2014

With data samples collected with the BESIII detector operating at the BEPCII storage ring at center-of-mass energies from 4.009 to 4.420 GeV, the process e+e-→ γX(3872) is observed for the first time with a statistical significance of 6.3σ. The measured mass of the X(3872) is (3871.9 ± 0.7s tat ± 0.2 syst) MeV/c(2), in agreement with previous measurements. Measurements of the product of the cross section σ[e+e- → γX(3872)] and the branching fraction B[X(3872)→π+π-J/ψ] at center-of-mass energies 4.009, 4.229, 4.260, and 4.360 GeV are reported. Our measurements are consistent with expectations for the radiative transition process Y(4260) → γX(3872).

2012

AIP Conference Proceedings, 2006

The European Physical Journal C, 2015

X(3872) still presents many puzzles more than a decade after its discovery. Some of its properties, like the isospin violating decays, can easily be accommodated in a molecular model, whereas its other properties, such as radiative decays can be more naturally explained in the quarkonium picture. The best of these schemes can be combined in a picture of X(3872) where it is dominantly a molecular state with some charmonium components. In this work, we present a model based on heavy quark symmetry which describes X(3872) as a superposition of molecular and charmonium components.

Physical Review D, 2006

Physical Review Letters, 2004

Physical Review Letters, 2004

We report the observation of the X(3872) in the J/ψπ+π- channel, with J/ψ decaying to μ+μ-, in pp¯ collisions at √(s)=1.96 TeV. Using approximately 230 pb-1 of data collected with the RunII D0 detector, we observe 522±100 X(3872) candidates. The mass difference between the X(3872) state and the J/ψ is measured to be 774.9±3.1(stat)±3.0(syst) MeV/c2. We have investigated the production and decay characteristics of the X(3872) and find them to be similar to those of the ψ(2S) state.