Publications

Order by: publication date number of citations

DIS physics at the EIC and LHeC and connections to the future LHC and $\nu$A programs

T. J. Hobbs

SciPost Phys. Proc. 8, 155 (2022) · published 14 July 2022 | · pdf

Deeply-inelastic scattering (DIS) stands to enter a golden age with the prospect of precision programs at the Electron-Ion Collider (EIC) and Large Hadron-electron Collider (LHeC). While these programs will be of considerable importance to resolving longstanding issues in (non)perturbative QCD as well as hadronic and nuclear structure, they will also have valuable implications for a wider range of physics at the Energy and Intensity Frontiers, including at the High-Luminosity LHC (HL-LHC) and future $\nu A$ facilities. In this plenary contribution, we highlight a number of salient examples of the potential HEP impact from the complementary EIC and LHeC programs drawn from their respective Yellow Report and Whitepaper. Interested readers are encouraged to consult the extensive studies and literature from which these examples are taken for more detail.

1 citation
Applying Quantum Tomography to Hadronic Interactions

J. C. Martens, J. P. Ralston, D. Tapia Takaki

SciPost Phys. Proc. 8, 154 (2022) · published 14 July 2022 | · pdf

A proper description of inclusive reactions is expressed with density matrices. Quantum tomography reconstructs density matrices from experimental observables. We review recent work that applies quantum tomography to practical experimental data analysis. Almost all field-theoretic formalism and modeling used in a traditional approach is circumvented with great efficiency. Tomographically-determined density matrices can express information about quantum systems which cannot in principle be expressed with distributions defined by classical probability. Topics such as entanglement and von Neumann entropy can be accessed using the same natural language where they are defined. A deep relation exists between {\it separability}, as defined in quantum information science, and {\it factorization}, as defined in high energyphysics. Factorization acquires a non-perturbative definition when expressed in terms of a conditional form of separability. An example illustrates how to go from data for momentum 4-vectors to a density matrix while bypassing almost all the formalism of the Standard Model.
Towards DIS at N4LO

Avanish Basdew-Sharma

SciPost Phys. Proc. 8, 153 (2022) · published 14 July 2022 | · pdf

We will report on an ongoing effort towards calculating the N4LO perturbative QCD corrections to the DIS total inclusive cross-section. We are developing a method based on differential equations and series expansion in the inverse Bjorken parameter. As a byproduct our calculation should also deliver analytic or at least precise numerical approximations for the four-loop splitting functions.
Multidimensional partial wave analysis of SIDIS dihadron beam spin asymmetries at CLAS12

C. Dilks

SciPost Phys. Proc. 8, 152 (2022) · published 14 July 2022 | · pdf

Dihadron beam spin asymmetries provide a wide range of insights into nucleon structure and hadronization. Recent measurements at CLAS12 provide the first empirical evidence of nonzero $G_1^\perp$, the parton helicity-dependent dihadron fragmentation function (DiFF) encoding spin-momentum correlations in hadronization. These measurements also allow for a point-by-point extraction of the subleading-twist PDF $e(x)$ in a collinear framework. We observe different behavior of the asymmetries in different invariant mass regions, motivating a fully multidimensional study. The DiFFs also expand in terms of partial waves, each corresponding to the interference of dihadrons of particular polarizations. Altogether a fully multidimensional partial wave analysis is needed, and this presentation will summarize the efforts and results obtained thus far.

2 citations
Drell-Yan transverse spectra at the LHC: a comparison of parton branching and analytical resummation approaches

Aron Mees van Kampen

SciPost Phys. Proc. 8, 151 (2022) · published 14 July 2022 | · pdf

I report on precision comparisons of theoretical predictions for Drell-Yan (DY) transverse momentum spectra from two approaches: the analytical resummation approach based on Collins-Soper-Sterman (CSS) formalism and the parton branching (PB) approach to the evolution of transverse momentum dependent (TMD) parton distributions.

1 citation
Exclusive electro-weak production of a charmed meson at high energy

B. Pire, L. Szymanowski, J. Wagner

SciPost Phys. Proc. 8, 150 (2022) · published 14 July 2022 | · pdf

Exclusive electro-weak processes have peculiar features which make them complementary to usually discussed deeply virtual electroproduction processes such as deep virtual Compton scattering or meson production (and the corresponding crossed reactions). They allow in particular single charmed meson production, which we study in two different contexts : electroproduction at an electron ion collider and neutrino-production at a medium energy neutrino facility. We rely on the QCD collinear factorization framework where generalized parton distributions allow physicists to perform a nucleon tomography.
Multidimensional, high precision beam spin asymmetry measurements of semi-inclusive pion production off the proton with CLAS12

S. Diehl

SciPost Phys. Proc. 8, 149 (2022) · published 14 July 2022 | · pdf

High precision measurements of the polarized electron beam-spin asymmetry in SIDIS from the proton have been performed using a 10.6 GeV incident electron beam and the CLAS12 spectrometer at Jefferson Lab. The proceeding reports a multidimensional study of the structure function ratio $F^{sin\phi}_{LU}/F_{UU}$ extracted from single pion ($\pi^{+}$, $\pi^{-}$, $\pi^{0}$) SIDIS data over a large kinematic range in $z$, $x_{B}$, $P_{T}$ and virtualities $Q^{2}$ ranging from 1~GeV$^2$ up to 7~GeV$^2$. $F^{sin\phi}_{LU}$ is a twist-3 quantity that can reveal novel properties of quark-gluon correlations within the nucleon.

1 citation
Subnucleon fluctuations in coherent and incoherent ultra-peripheral AA collisions at LHC and RHIC with the Sartre event generator

Tobias Toll

SciPost Phys. Proc. 8, 148 (2022) · published 14 July 2022 | · pdf

Sartre has been extensively used for describing photon-nuclei processes at the electron-ion collider (EIC) as well as ultra-peripheral collisions (UPC) at LHC and RHIC. Sartre is an event generator which implements the dipole model for DIS, and models the transverse geometry of the target nucleus or proton in coordinate space. It uses the Good-Walker mechanism for simulating fluctuations which contribute to the incoherent cross section for which the target breaks up after the interaction. With improved precision of UPC measurements in the last years, a detailed test of the dipole model has become possible, and Sartre's model was found lacking. In these proceedings we add subnucleon fluctuations to the nucleus and show that this is sufficient for describing the vast majority of the present measurements. We also find that for larger momentum transfers in the nucleus, which probes gluon fluctuations at higher resolution, the current complexity of the model may not suffice. Future measurements at the LHC, RHIC and especially the EIC has the potential to reveal these gluon vacuum fluctuations and glean novel insights into the self-interacting quantum field of QCD.

2 citations
Probing quantum entanglement and collectivity effects in e+p collisions at HERA H1

Chuan Sun

SciPost Phys. Proc. 8, 147 (2022) · published 14 July 2022 | · pdf

Charged particle multiplicity spectra are measured at HERA H1 in DIS process at 319 GeV. The hadron entropy determined from the multiplicity spectra is compared to the gluon entropy predicted from a quantum-entanglement model. On the other hand, observed collective behaviours in high multiplicity pA, pp and ultra-peripheral PbPb collisions at RHIC and LHC motivate a study in ep collisions. Two- and multi-particle correlations are studied in DIS, as well as photoproduction events with collision energy <Wγp>~270 GeV.
Transverse spin asymmetries for inclusive $\rho^0$ production in SIDIS at COMPASS

A. Kerbizi

SciPost Phys. Proc. 8, 146 (2022) · published 14 July 2022 | · pdf

The production of vector mesons in SIDIS is a particularly interesting channel to study the polarized fragmentation and related phenomena. Preliminary COMPASS results for the first measurement of inclusive $\rho^0$ Collins and Sivers transverse-spin asymmetries are presented here for the first time. The analysis is based on the data-set collected by COMPASS in $2010$ using a $160\, \rm{GeV}/c$ $\mu^+$ beam and a transversely polarized $NH_3$ target. The asymmetries are extracted as function of Bjorken-$x$, of the total transverse momentum of the oppositely charged hadron pair and of the fraction of available energy $z$ carried by the pair. Indications for positive Collins and Sivers asymmetries are obtained as expected from models.

Previous 1 ... 24 25 26 27 28 29 30 31 32 33 34 ... 67 Next

Publications

1 citation

2 citations

1 citation

1 citation

2 citations