Clues for the existence of twoK1(1270)resonances

Abstract

The axial vector meson K1(1270) was studied within the chiral unitary approach, where it was shown that it has a two-pole structure. We reanalyze the high-statistics WA3 experiment K − p → K − π + π − p at 63 GeV, which established the existence of both K1(1270) and K1(1400), and we show that it clearly favors our two-pole interpretation. We also reanalyze the traditional K-matrix interpretation of the WA3 data and find that the good fit of the data obtained there comes from large cancellations of terms of unclear physical interpretation.

S-waveKK*interactions in a finite volume and thefGeng1, Ren2, Zhou3 et al. 2015Phys. Rev. D292330View full textAdd to dashboardCite

“…In recent years, however, it has been suggested to be a dynamically generated state made from the KK * interaction, together with its axial-vector counterparts [2,3]. Such a picture has been extensively tested in the past decade [4][5][6][7][8][9][10][11][12][13][14]. All these studies yield consistent results that the ground-state axial-vector mesons can be understood as dynamically generated states or at least contain large pseudoscalar meson-vector meson components.…”

Pseudoscalar meson and vector meson interactions and dynamically generated axial-vector mesons

“…We have checked that including the widths as suggested in Ref. [18] does not change qualitatively the obtained pole positions and couplings. On the other hand, we have no information on how the widths change with varying light quark masses and therefore cannot incorporate the widths into our studies of the scattering lengths and the pole positions without making further assumptions.…”

“…[6] the two poles found in the isospin 1/2 and strangeness 1 channel are both claimed to be the K 1 (1270)-the so-called two-pole picture. 1 Such a dynamical picture has been put into test in many different scenarios, e.g., the two-pole structure of the K 1 (1270) [18], their radiative decays [19][20][21][22], their large N c behavior [23], the composite and elementary nature of the a 1 (1260) [24] and its finite volume dependence [25]. All these studies suggest that the axial-vector mesons contain large pseudoscalar meson-vector meson components.…”

Description of ρ(1700) as a $$\rho K\bar K$$ system with the fixed-center approximation

“…Namely in the present case of the ρKK system, the ρK (ρK) unitarized amplitude is necessary. In the previous work [29,30], the vector-pseudoscalar interaction in the sector with strangeness S = 1 and isospin I = 1/2 was studied within the framework of the chiral unitary approach and that interaction was shown to generate two resonance poles corresponding to the K 1 (1270) resonance. Here we are going to follow the scheme of refs.…”

“…In order to obtain the ρK amplitude, we follow the schemes given by refs. [29,30] and extend them to the isospin I = 3/2 sector.…”