Near-ThresholdΛ(1520)Production by theγ→p→K+Λ(

Abstract

Differential cross sections and photon-beam asymmetries for the gamma(p)-->K{+}Lambda(1520) reaction have been measured with linearly polarized photon beams at energies from the threshold to 2.4 GeV at 0.6<cos(theta){c.m.}{K}<1. A new bump structure was found at W approximately 2.11 GeV in the cross sections. The bump is not well reproduced by theoretical calculations introducing a nucleon resonance with J<or=3/2. This result suggests that the bump might be produced by a nucleon resonance possibly with J>or=5/2 or by a new reaction process, for example, an interference effect with the phi photoproduction having a similar bump structure in the cross sections.

Differential photoproduction cross sections of theΣ0(1385),Λ(1405), andMoriya1, Schumacher2, Adhikari3 et al. 2013Phys. Rev. CSelf Cite

“…In the threshold region, Ref. [14] measured the rapidly-rising differential cross section with finer energy binning than our present results. Points that overlap with our bins are shown as the open circles in Fig.…”

“…Their affirmative conclusion about the need for these resonances is in disagreement with the previous work by Nam et al cited in Ref. [14], and their quantitative agreement with the Λ(1520) differential cross section and with the beam asymmetry were not good. We can expect that the more complete angular distributions presented below will be useful in refining these models.…”

“…This model includes K * exchange, and although this is more important at higher energies, it may help reproduce the forward-angle behavior we see. This model also includes the s-channel N (2080)D 13 resonance that was quite significant when matching the data of Kohri et al from LEPS [14]. (See also the earlier work in Ref.…”

“…In more recent times, the LEPS Collaboration has looked at photoproduction of this hyperon in the energy region 1.9 < E γ < 2.8 GeV using a forward-angle spectrometer [13,14]. They showed that the cross section is forward peaked, and that this behavior is more consistent with a model dominated by a gauge-invariance-preserving contact term [15,16], and less consistent with models dominated by t−channel vector meson K * exchange [17,18].…”

Photoproduction of $\pi^{-}\Delta^{++}$ and $\pi^{+}\Delta^{0}$ on the proton for the comparison of $\bar{u}u$ and $\bar{d}d$ productions

“…The LEPS spectrometer was designed to efficiently detect φ -mesons decaying to K + and K − at forward angles [1,2,3,4,5]. Not only φ but also K + photoproduction reactions are extensively studied [6,7,8,9,10,11,12,13].…”