Production of tetraquarks at the LHC

Abstract

The high prompt production cross section of Xð3872Þ at hadron colliders has shown to be very informative about the quark nature of the X, Y, Z states. We present here a number of results on X production in ppðpÞ collisions obtained with Monte Carlo hadronization methods and illustrate what can be learned from their use to improve our understanding of exotic states. In particular, a comparison between antideuteron and X production cross sections is proposed. Hadronization might be the key to solve the problem of the extra states expected in diquark-antidiquark models which are naturally favored after the recent confirmation of the Zð4430Þ tetraquark, together with its lower partners Z c ð3900Þ and Z 0 c ð4020Þ.

The hidden-charm pentaquark and tetraquark states

“…Its production at the Tevatron and LHC was studied in Refs. [707,708,709]. Its production at CDF was studied in Ref.…”

Tetraquarks in the 1/N expansion and meson-meson resonances

“…Thus far, no 'smoking gun' signature has been found to distinguish the different interpretations, with the exception of the naive, loosely bound, molecular model, largely unfavored by the production cross section of X(3872) at large p T in high energy hadron colliders [23][24][25][26]; for a compelling comparison with some recent Alice data see [27]. Perhaps, these models are, after all, different but complementary descriptions of the same QCD underlying reality.…”

Four-quark hadrons: An updated review

“…The validity of this qualitative expectation and of the coalescence model for the case of the anti-deuteron has been successfully tested 206 using the well-known Monte Carlo (MC) generator HERWIG. 207 In particular this tool has been used to evaluate the number ofpn pairs produced with small relative momentum (k 0 < 80 MeV) in pp collisions at √ s = 7 TeV in the interval 0.9 GeV< p T < 1.4 GeV.…”

“…38. Anti-deuteron events produced in pp collisions according to 10 9 HERWIG events with |η| < 0.9 (blue solid line) and |y| < 1.2 (green solid line) as a function of the transverse momentum of the molecule, from Guerrieri et al 206 The MC simulation is compared to the ALICE deuteron production data 208 (red circles) and with the CMS X(3872) data 93 (green squares).…”