Leading Baryon Production Research Articles

Baryon production probability via the nuclear configurational entropy

We study the net-baryon production at forward rapidities within the Color Glass Condensate paradigm. At high energy regime, the leading baryon production mechanism is shown to change from recombination to independent fragmentation. The nuclear configurational entropy (NCE) constructed upon forward scattering amplitudes allows to predict the two free parameters that govern the anomalous dimension of the target gluon distribution. The global minimum of the NCE indicates a point of stability in pp/pA/AA collisions at LHC energies, corroborating and matching RHIC data for hadron spectra measured in pp and dAu collisions at RHIC energies, with accuracy between 1.2 and 1.8%, respectively, for the two free parameters.

Net baryon production in the CGC formalism

In this work the net-baryon production at forward rapiditiesis investigated considering the CGC formalism. We assume that at large energies the coherence of the projectile quarks is lost and that the leading baryon production mechanism changes from recombination to independent fragmentation. The phenomenological implications for net-baryon production in pp/pA/AA collisions are analyzed and predictions for LHC energies are presented. We also extend previous studies to pp and pA collisions and estimate for the first time the nuclear modification ratio, equal to the ratio of the net-proton production cross section in pA collisions over the one in pp collisions, scaled by the number of binary collisions, for leading baryon production.

Baryon stopping and Feynman scaling in the color glass condensate approach

In this work baryon stopping and leading baryon production are investigated in the context of the color glass condensate (CGC) formalism. We assume that at large energies the coherence of the projectile quarks is lost and that the leading baryon production mechanism changes from recombination to independent fragmentation. The phenomenological implications for net-baryon production in pp/pA/AA collisions are analyzed and predictions for LHC energies are presented. We find that at very high energies the leading baryon xF spectra become nearly energy independent and we reach the approximate Feynman scaling regime.

Baryon stopping in the color glass condensate formalism: A phenomenological study

The net-baryon production at forward rapidities is investigated considering the Color Glass Condensate formalism. We assume that at large energies the coherence of the projectile quarks is lost and that the leading baryon production mechanism changes from recombination to independent fragmentation. The phenomenological implications for net-baryon production in $pp/pA/AA$ collisions are analysed and predictions for LHC energies are presented.

Leading baryons at HERA

Recent results on leading baryon production in ep scattering from the ZEUS and H1 collaborations are presented and compared with different production models.

How to Probe High Gluon Densities inppCollisions at the Large Hadron Collider

We present a model for hadron production in the proton fragmentation region in pp collisions at the CERN Large Hadron Collider which accounts for the first time for effects of very strong small x gluon fields. Average transverse momenta acquired by the valence quarks exceed 1 GeV/c for central collisions and result in the suppression of leading baryon production and an additional energy flow to smaller rapidities. A strong dependence on the impact parameter will allow one to investigate the propagation of leading partons through gluon fields of a strength comparable to the ones encountered in heavy ion collisions at the LHC and in cosmic-ray-air interactions at highest energies.

Leading baryons at HERA

H1 and ZEUS results on leading baryon production in ep scattering are presented. The data are shown to be consistent with particle exchange models of baryon production, and the pion structure function is extracted.

Leading baryon production in p+A collisions at relativistic energies

Leading baryon production in p+A collisions at relativistic energies

Measurement of inclusive scattering and leading baryon production at HERA

Measurements of the proton structure function F 2 in inclusive deep inelastic e + p scattering at HERA are presented. For events with a leading proton or neutron detected in the forward region, semi-inclusive cross sections are shown. The leading neutron data allowed a first estimate of the pion structure function at small x.

Leading baryon production at ZEUS

Using the ZEUS forward detectors, the Leading Proton Spectrometer (LPS) and the Forward Neutron Calorimeter (FNC), the spectrum of neutrons and protons with fractional momentum with respect to the proton beam momentum, x L > 0.2, was measured. The structure function of Deep Inelastic Scattering (DIS) events with a leading baryon F 2 LB , were determined. It was found that DIS events with a leading baryon behave like normal DIS events with respect to x BJ and Q 2.

Leading baryon production in deep inelastic scattering at HERA

Deep-inelastic scattering events with a leading baryon have been detected by the H1 experiment at HERA using a forward proton spectrometer and a forward neutron calorimeter. Semi-inclusive cross sections have been measured in the kinematic region 2 ⩽ Q 2 ⩽ 50 GeV 2, 6·10 −5 ⩽ x ⩽ 6·10 −3 and baryon p T ⩽ 200 MeV. A Regge model of leading baryon production which consists of pion, pomeron and secondary reggeon exchanges gives an acceptable description of both semi-inclusive cross sections in the region 0.1 ⩽ x P ⩽ 0.3. The leading neutron data are used to estimate the structure function of the pion at small Bjorken- x.

Pion exchange and the H1 forward spectrometer data

We point out that the \(\Delta\pi\) component of the nucleon wave function is vital to the interpretation of the recent H1 data for leading baryon production. While the n/p ratio is equal to two with the \(N\pi\) component alone, the inclusion of the \(\Delta\pi\) component brings this ratio very near to unity, as observed in the experiment. This result demonstrates that pion exchange can not only account for leading neutron but also for a large fraction of the leading proton production.

Pion exchange and the H1 forward spectrometer data

We point out that the $\Delta\pi$ component of the nucleon wave function is vital to the interpretation of the recent H1 data for leading baryon production. While the $n/p$ ratio is equal to two with the $N\pi$ component alone, the inclusion of the $\Delta\pi$ component brings this ratio very near to unity, as observed in the experiment. This result demonstrates that pion exchange can not only account for leading neutron but also for a large fraction of the leading proton production.

Measurement of leading proton and neutron production in deep-inelastic scattering at HERA

Deep--inelastic scattering events with a leading baryon have been detected by the H1 experiment at HERA using a forward proton spectrometer and a forward neutron calorimeter. Semi--inclusive cross sections have been measured in the kinematic region 2 = 160 GeV. The measurements are used to test production models and factorization hypotheses. A Regge model of leading baryon production which consists of pion, pomeron and secondary reggeon exchanges gives an acceptable description of both semi-inclusive cross sections in the region 0.7 <= E'/E_p <= 0.9, where E_p is the proton beam energy. The leading neutron data are used to estimate for the first time the structure function of the pion at small Bjorken--x.

Differences in leading baryon production from p [formula omitted] and pp collisions with √ s=31 GeV at the CERN-ISR

Significant differences are observed between forward-produced Δ ++(1232) and Λ 0's in pp interactions and their corresponding anti-particles in p p interactions, as expected from quark counting and single q q annihilation. A possible relationship between these results and the p p -pp total cross section difference is discussed.