Observation of tt¯γγ production at s=13 TeV with the ATLAS detector
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, cilt.874, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 874
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.physletb.2026.140195
- Dergi Adı: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, INSPEC, MathSciNet, zbMATH, Directory of Open Access Journals
- Anahtar Kelimeler: Top-quark pair production in association with two photons
- Ankara Üniversitesi Adresli: Evet
Özet
This paper presents the first observation of top-quark pair production in association with two photons (tt¯γγ). The measurement is performed in the single-lepton decay channel using proton-proton collision data collected by the ATLAS detector at the Large Hadron Collider. The data correspond to an integrated luminosity of 140 fb−1 recorded during Run 2 at a centre-of-mass energy of 13 TeV. The tt¯γγ production cross section, measured in a fiducial phase space based on particle-level kinematic criteria for the lepton, photons, and jets, is found to be 2.42−0.53+0.58fb, corresponding to an observed significance of 5.2 standard deviations. Additionally, the ratio of the production cross section of tt¯γγ to top-quark pair production in association with one photon is determined, yielding (3.30−0.65+0.70)×10−3.