TY  - JOUR
AU  - Falcioni, G.
AU  - Herzog, F.
AU  - Moch, S.
AU  - Pelloni, A.
AU  - Vogt, A.
TI  - Four-loop splitting functions in QCD – the gluon-gluon case –
JO  - Physics letters / B
VL  - 860
IS  - DESY-24-144
SN  - 0031-9163
CY  - Amsterdam
PB  - North-Holland Publ.
M1  - PUBDB-2024-06094
M1  - DESY-24-144
M1  - arXiv:2410.08089
M1  - ZU-TH 47/24
M1  - LTH 1384
SP  - 139194
PY  - 2025
N1  -  the DFG through the Research Unit FOR 2926, project number 40824754, and DFG grant MO 1801/4-2, and the ERC Advanced Grant 101095857.
AB  - We present the even-N moments N ≤ 20 of the fourth-order (N<sup>3</sup>LO) contribution P<sub>gg</sub><sup> (3)</sup>(x) to the quark-to-gluon splitting function in perturbative QCD. These moments, obtained by analyticallycomputing off-shell operator matrix elements for a general gauge group, agree with all known results, in particular with the moments N ≤ 10 derived before from structure functions in deep-inelastic scattering.  Using the new moments and the available endpoint constraints, we construct approximations for P<sub>gg</sub><sup> (3)</sup>(x) which improve upon those obtained from the lowest five even moments. The remaining uncertainties of this function are now practically irrelevant at momentum fractions x  >  0.1. The resulting errors of the convolution ofP<sub>gg</sub> at N<sup>3</sup>LO with a typical gluon distribution are small at x  >~10<sup>−3</sup> and exceed 1% only at x  <~10<sup>−4</sup> for a strong coupling α<sub>s</sub> = 0.2. The present results for P<sub>gg</sub><sup> (3)</sup>(x) should thus be sufficient for most collider-physics applications.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:001394711600001
DO  - DOI:10.1016/j.physletb.2024.139194
UR  - https://bib-pubdb1.desy.de/record/615336
ER  -