12th International workshop on Multiple Partonic Interactions at the LHC

Session

WG4: small-x and diffraction

11 Oct 2021, 16:45

Auditorium (LIP Lisbon)

Conveners

WG4: small-x and diffraction: WG4: Small x & Diffraction

• Albert Bursche (South China Normal University)
• Martin Hentschinski (Universidad de las Americas Puebla)
• Michele Gallinaro (LIP)

WG4: small-x and diffraction

• Martin Hentschinski (Universidad de las Americas Puebla)
• Albert Bursche (South China Normal University)
• Michele Gallinaro (LIP)

WG4: small-x and diffraction

• Albert Bursche (South China Normal University)
• Michele Gallinaro (LIP)
• Martin Hentschinski (Universidad de las Americas Puebla)

WG4: small-x and diffraction

• Albert Bursche (South China Normal University)
• Martin Hentschinski (Universidad de las Americas Puebla)
• Michele Gallinaro (LIP)

WG4: small-x and diffraction

• Michele Gallinaro (LIP)
• Martin Hentschinski (Universidad de las Americas Puebla)
• Albert Bursche (South China Normal University)

WG4: small-x and diffraction: summary and discussion

• Martin Hentschinski (Universidad de las Americas Puebla)
• Michele Gallinaro (LIP)
• Albert Bursche (South China Normal University)

21. Measurement of lepton-jet correlation in deep-inelastic scattering with the H1 detector using machine learning for unfolding

Ben Nachman (LBNL)

11/10/2021, 16:45

WG4: Small-x and Diffraction

The first measurement of lepton-jet momentum imbalance and azimuthal correlation in lepton-proton scattering at high momentum transfer is presented. These data, taken with the H1 detector at HERA, are corrected for detector effects using an unbinned machine learning algorithm (OmniFold), which considers eight observables simultaneously in this first application. The unfolded cross sections are...

7. Forward dijet production at the EIC: beyond the TMD factorization

Farid Salazar (Stony Brook University)

11/10/2021, 17:10

WG4: Small-x and Diffraction

The measurement of azimuthal correlations in the production of forward dijet in deep inelastic scattering provides a unique channel to access the small-x regime of the Weizsäcker-Williams gluon TMD. Its study could potentially provide signatures of gluon saturation at the future Electron-Ion Collider.

While the TMD factorization for semi-inclusive dijet production is expected to hold in...

39. Double parton scattering via photon-proton interactions and the transverse proton structure

Matteo Rinaldi (Dipartimento di Fisica e Geologia. Università degli studi di Perugia. Istituto Nazionale di Fisica Nucleare, sezione di Perugia.)

13/10/2021, 11:00

WG4: Small-x and Diffraction

In this contribution, we present possible appealing advantages offered by double parton scattering (DPS) processes via photon-proton interactions. In fact, as discussed in the proton-proton collisions framework, the DPS cross section depends on the double parton distribution functions (dPDFs) of the protons. These new quantities encode new information on the 3D partonic structure of the...

93. Very forward particle production and searches (FASER, etc)

Maria Vittoria Garzelli (Universitaat Hamburg (DE))

13/10/2021, 11:30

3. Elastic photon-initiated production at the LHC: the role of hadron-hadron interactions

Lucian Harland-Lang (University of Oxford)

13/10/2021, 13:30

WG4: Small-x and Diffraction

We discuss the role of additional hadron-hadron interactions in elastic photon-initiated production at the LHC, both in proton and heavy ion collisions. We in particular assess different sources of uncertainty associated with these cross sections, and compare with other calculations in the literature. A key result of our analysis is that the uncertainty associated with the survival factor is...

94. Parton distribution functions: measurements and interpretations

Mark Sutton (ATLAS Collaboration)

13/10/2021, 14:00

95. Results on diffraction and exclusive production

Gustavo Gil Da Silveira (Universidade do Estado do Rio de Janeiro)

13/10/2021, 14:30

5. The Electron Ion Collider and gluon imaging using azimuthal correlations at the EIC

Heikki Mäntysaari (University of Jyväskylä)

13/10/2021, 15:15

WG4: Small-x and Diffraction

We calculate azimuthal correlations between the exclusively produced virtual photon or vector meson and the scattered electron in Deep Inelastic Scattering processes at the future Electron-Ion Collider (EIC). We identify "kinematical" and "intrinsic" contributions to these correlations. Performing explicit calculations within the Color Glass Condensate framework we show that the correlations...

96. Results from peripheral and ultra-peripheral collisions at the LHC

Giulia Manca (Universita` degli studi di Cagliari and INFN, Cagliari, IT)

13/10/2021, 15:40

18. Small x gluon PDF from LHCb exclusive J/psi data

Chris Flett (The University of Jyväskylä)

14/10/2021, 11:00

WG4: Small-x and Diffraction

The exclusive J/psi production process within a `tamed’ collinear factorisation approach to NLO is described, giving a stable and reliable theoretical prediction owing to the resummation of a class of large logarithms and implementation of a crucial low Q_0 subtraction. A comparison with data from HERA and LHCb is made, before an extraction of a low x ~ 3*10^{-6} and low scale mu^2 ~ 2.4 GeV^2...

12. Accessing the proton UGD via exclusive polarized rho-meson leptoproduction at HERA and the EIC

Francesco Giovanni Celiberto (ECT*/FBK Trento & INFN-TIFPA)

14/10/2021, 11:20

WG4: Small-x and Diffraction

We study the exclusive polarized leptoproduction of ρ-mesons within the framework of high-energy factorization. Cross sections for longitudinally and transversally polarized mesons are presented. We employ a wide variety of unintegrated gluon distributions available in the literature and compare to HERA data. The resulting cross sections strongly depend on the choice of unintegrated gluon...

23. Measurement of exclusive pi+pi- and rho0 meson photoproduction at HERA

Sergey Levonian (DESY)

14/10/2021, 11:40

WG4: Small-x and Diffraction

Exclusive photoproduction of $\rho^0(770)$ mesons is studied using the H1 detector at the ep collider HERA. A sample of about 900000 events is used to measure single- and double-differential cross sections for the reaction $\gamma{}p\to\pi^{+}\pi^{-}Y$. Reactions where the proton stays intact ($m_Y=m_p$) are statistically separated from those where the proton dissociates to a low-mass hadronic...

101. WG4: summary and discussion (20´+15´)

Albert Bursche (South China Normal University), Martin Hentschinski (Universidad de las Americas Puebla), Michele Gallinaro (LIP)

15/10/2021, 14:50