From Ds± production asymmetry at the LHC to prompt ν at IceCube

Abstract

The description of the heavy meson production at large energies and forward rapidities at the LHC is fundamental to derive realistic predictions of the prompt atmospheric neutrino flux at the IceCube Observatory. In particular, the prompt tau neutrino flux is determined by the decay of Ds mesons produced in cosmic ray -air interactions at high energies and large values of the Feynman -xF variable. Recent data from the LHCb Collaboration indicate a production asymmetry for D + s and D − s mesons, which cannot be explained in terms of the standard modelling of the hadronization process. In this paper we demonstrate that this asymmetry can be described assuming an asymmetric strange sea (s(x) =s(x)) in the proton wave function and taking into account of the charm and strange fragmentation into Ds mesons. Moreover, we show that the strange quark fragmentation contribution is dominant at large -xF (≥ 0.3). The prompt ντ flux is calculated and the enhancement associated to the strange quark fragmentation contribution, disregarded in previous calculations, is estimated.

New vistas in charm production

“…Here we have presented and discussed briefly some results on asymmetry in the production of D + and D − [6] as well as D + s D − s mesons [12] observed recently by the LHCb collaboration [4,5]. Here we have discussed a scenario in which subleading (unfavored) fragmentation q/q → D ± is responsible for the asymmetry.…”

“…In Ref. [12] we showed also results for √ s = 8 TeV. The data points are taken from IceCube analysis [11].…”

Production of $\nu_{\tau}$ neutrinos and ${\overline \nu}_{\tau}$ antineutrinos - elaborate calculation for a fixed target experiment SHiP

“…Similarly, fragmentation of light partons into heavy mesons may be well possible [8]. In the present study we will discuss also results of P hadronization to D s mesons in this context as well as our simple model of subleading fragmentation s → D − s ands → D + s [4]. The s ands distributions are calculated here in the leading-order (LO) collinear factorization approach with on-shell initial state partons and with a special treatment of minijets at low transverse momenta, as adopted e.g.…”

“…In our model D ± s mesons can be produced from both, charm and strange quark/antiquark fragmentation, with a similar probability of the transition. The s → D s mechanism is expected to be especially important at large rapidities (or large Feynman x F ) [4]. Here we wish to answer whether it has consequences for forward production of neutrinos/antineutrinos for the SHiP experiment or not.…”

Production asymmetry of ντ neutrinos and $$ {\overline{\nu}}_{\tau } $$ antineutrinos from a fixed target experiment SHiP

“…In our model D ± s mesons can be produced from both, charm and strange quark/antiquark fragmentation, with a similar probability of the transition. The s → D s mechanism is expected to be especially important at large rapidities (or large Feynman x F ) [13]. Does it has consequences for forward production of neutrinos/antineutrinos for the SHiP experiment?…”