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Heidi Sandaker

Professor - Norwegian center for CERN research

E-post heidi.sandaker@fys.uio.no

Brukernavn

Besøksadresse Sem Sælandsvei 24 Fysikkbygget 0371 Oslo

Postadresse Postboks 1072 Blindern 0316 Oslo

Last ned visittkort

Faglige interesser

Partikkelfysikk, astropartikkel fysikk, detektorutvikling

Mørk materie søk, supersymmetri og silisium detektor R&D

Medlem av ATLAS og AEGIS eksperimentene på CERN og CTA observatoriet

Undervisning

Mini-vinterskole CERN

Bakgrunn

2010 - 2014 : Forsker Universitetet i Bergen

2007 - 2010 : Postdoktor Universitetet i Bergen

2005 - 2007 : Fellow CERN

2005 : PhD Universitetet i Oslo

Priser

2009 - Stipend fra Bergens forskningsstiftelse
2008 - Meltzer stipend

Verv

Leder av SDI endringsmiljø

Leder av AEGIS prosjektet i Norge (NFR - FRINATTEK)

Leder CTA Norge

Samarbeid

Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 863 forfattere av denne artikkelen] (2026). Measurements of Z-Boson Pair Entanglement in Decays of Higgs Bosons at the ATLAS Experiment. Physical Review Letters. ISSN 0031-9007. 137(11). doi: 10.1103/y1nh-1b82.
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 842 forfattere av denne artikkelen] (2026). Evidence of ZZγ Production with the ATLAS Detector. Physical Review Letters. ISSN 0031-9007. 137(9), s. 091804–091804. doi: 10.1103/jngg-1nf3. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 860 forfattere av denne artikkelen] (2026). Measurement of Charged-Particle Production in sqrt[s_{NN}]=9.62 TeV Proton-Oxygen Collisions as a Probe of Cosmic-Ray Air Showers with the ATLAS Detector. Physical Review Letters. ISSN 0031-9007. 137(12), s. 121901–121901. doi: 10.1103/f3nk-5lt9. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 875 forfattere av denne artikkelen] (2026). Search for charginos and neutralinos with B - L R-parity violating decays inpffisffi=13 TeV and 13.6 TeV pp collisions with the ATLAS detector. Physical Review D. ISSN 2470-0010. 114(5). doi: 10.1103/RP69-XGKD. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 865 forfattere av denne artikkelen] (2026). Measurements of the Higgs boson production, fiducial and differential cross-sections in the four lepton decay channel using 164 fb−1of data collected at √s=13.6 TeV with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2026(8). doi: 10.1007/JHEP08(2026)052. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 843 forfattere av denne artikkelen] (2026). Search for displaced decays of long-lived particles in events with missing transverse momentum in √s=13 TeV pp collisions with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2026(8). doi: 10.1007/JHEP08(2026)016. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 849 forfattere av denne artikkelen] (2026). Search for Higgs boson pair production in association with top-quark pairs using 196 fb−1of proton–proton collision data at √s=13 and 13.6 TeV with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2026(8). doi: 10.1007/JHEP08(2026)020. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 850 forfattere av denne artikkelen] (2026). A search for lepton-flavour violating t ? 3µ decays with the ATLAS detector. Physics Letters B. ISSN 0370-2693. 880. doi: 10.1016/j.physletb.2026.140748.
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 928 forfattere av denne artikkelen] (2026). Measurement of the azimuthal anisotropy of charged particles in √sNN = 5.36 TeV16O+16O and20Ne+20Ne collisions with the ATLAS detector. Physical Review C. ISSN 2469-9985. 113(4). doi: 10.1103/XQXZ-8BHF.
Zwalinski, L.; Zormpa, O.; Zorbas, T. G.; Zografos, A.; Zoch, K. & Zoccoli, A. [Vis alle 2 934 forfattere av denne artikkelen] (2026). Precise measurement of the tt¯ production cross-section and lepton differential distributions in eμ dilepton events from √s=13TeVpp collisions with the ATLAS detector. European Physical Journal C. ISSN 1434-6044. 86(5). doi: 10.1140/epjc/s10052-026-15311-0. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 925 forfattere av denne artikkelen] (2026). Characterization of nuclear breakup as a function of hard-scattering kinematics using dijets measured by ATLAS in p+Pb collisions. Physics Letters B. ISSN 0370-2693. 877. doi: 10.1016/j.physletb.2026.140440.
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 939 forfattere av denne artikkelen] (2026). Search for a resonance decaying into a scalar particle and a Higgs boson in the final state with two bottom quarks and two photons with 199 fb−1 of data collected at √s=13 and 13.6 TeV with the ATLAS detector. Physics Letters B. ISSN 0370-2693. 877. doi: 10.1016/j.physletb.2026.140425. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 842 forfattere av denne artikkelen] (2026). Search for massive, long-lived particles in events with displaced vertices and displaced muons in pp collisions at √s=13.6 TeV with the ATLAS experiment. Physics Letters B. ISSN 0370-2693. 878. doi: 10.1016/j.physletb.2026.140509. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 939 forfattere av denne artikkelen] (2026). Search for higgsinos in compressed mass spectra using low-momentum tracks in pp collisions at √s=13 TeV with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2026(6). doi: 10.1007/JHEP06(2026)094. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 859 forfattere av denne artikkelen] (2026). Search for dimuon resonance in the 35 to 75 GeV mass range using 140 fb−1 of 13 TeV pp collisions with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2026(6). doi: 10.1007/JHEP06(2026)165. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 863 forfattere av denne artikkelen] (2026). Combined effective field theory interpretation of measurements sensitive to quartic gauge boson couplings in pp collisions at √s=13 TeV with the ATLAS detector. Physics Letters B. ISSN 0370-2693. 879. doi: 10.1016/j.physletb.2026.140683. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 934 forfattere av denne artikkelen] (2026). Differential cross-section measurements of coherent production of singly and doubly resonant top-quark in WWbb events with one lepton at √s=13 TeV with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2026(7). doi: 10.1007/JHEP07(2026)028. Fulltekst i vitenarkiv
Zwalinski, L.; Zormpa, O.; Zorbas, T. G.; Zografos, A.; Zoch, K. & Zoccoli, A. [Vis alle 2 932 forfattere av denne artikkelen] (2026). Search for emerging jets in pp collisions at √s=13TeV with the ATLAS experiment. European Physical Journal C. ISSN 1434-6044. 86(7). doi: 10.1140/epjc/s10052-026-15693-1. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 860 forfattere av denne artikkelen] (2026). Measurement of the |Vcb| element of the CKM matrix in tt¯ decays with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2026(7). doi: 10.1007/JHEP07(2026)078. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 860 forfattere av denne artikkelen] (2026). Measurement of the Higgs boson production in association with top quarks in multilepton final states in pp collisions at √s=13 TeV with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2026(5). doi: 10.1007/JHEP05(2026)183. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 934 forfattere av denne artikkelen] (2026). Measurement of differential t-channel single top (anti)quark production cross-sections at 13 TeV with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2026(5). doi: 10.1007/JHEP05(2026)174. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 933 forfattere av denne artikkelen] (2026). Search for long-lived particles using displaced vertices of oppositely charged leptons in 140fb−1 of pp collisions at √s=13 TeV with the ATLAS detector. Physics Letters B. ISSN 0370-2693. 878. doi: 10.1016/j.physletb.2026.140497. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 938 forfattere av denne artikkelen] (2026). Study of Higgs boson pair production in the HH→bb‾γγ final state with 308 fb−1 of data collected at √s= 13 TeV and 13.6 TeV by the ATLAS experiment. Physics Letters B. ISSN 0370-2693. 876. doi: 10.1016/j.physletb.2026.140280. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 923 forfattere av denne artikkelen] (2026). Search for Higgs bosons produced in association with a high-energy photon via vector-boson fusion and decaying to a pair of b-quarks in the ATLAS detector. Physics Letters B. ISSN 0370-2693. doi: 10.1016/j.physletb.2026.140279. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 925 forfattere av denne artikkelen] (2026). Measurement of coherent exclusive J/ψ → μ+μ−production in ultraperipheral Pb+Pb collisions at √sNN = 5.36 TeV with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2026(4). doi: 10.1007/JHEP04(2026)020. Fulltekst i vitenarkiv
Zwalinski, L.; Zormpa, O.; Zorbas, T. G.; Zografos, A.; Zoch, K. & Zoccoli, A. [Vis alle 2 931 forfattere av denne artikkelen] (2026). Search for Beyond the Standard Model physics with anomaly detection in multilepton final states in pp collisions at √s = 13 TeV with the ATLAS detector. European Physical Journal C. ISSN 1434-6044. 86(3). doi: 10.1140/epjc/s10052-025-15218-2. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 929 forfattere av denne artikkelen] (2026). Measurement of the top-quark Yukawa coupling from tt production in the lepton+jets final state using pp collisions at √s = 13 TeV with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2026(1). doi: 10.1007/JHEP01(2026)117. Fulltekst i vitenarkiv
Zwalinski, L.; Zormpa, O.; Zorbas, T. G.; Zografos, A.; Zoch, K. & Zoccoli, A. [Vis alle 2 929 forfattere av denne artikkelen] (2026). Search for heavy neutral leptons in decays of W bosons produced in 13 TeV pp collisions using prompt signatures in the ATLAS detector. European Physical Journal C. ISSN 1434-6044. 86(2). doi: 10.1140/epjc/s10052-025-15191-w. Fulltekst i vitenarkiv
Zwalinski, L.; Zormpa, O.; Zorbas, T. G.; Zografos, A.; Zoch, K. & Zoccoli, A. [Vis alle 2 926 forfattere av denne artikkelen] (2026). Transforming jet flavour tagging at ATLAS. Nature Communications. 17(1). doi: 10.1038/s41467-025-65059-6. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 934 forfattere av denne artikkelen] (2026). Observation of tt¯γγ production at √s=13 TeV with the ATLAS detector. Physics Letters B. ISSN 0370-2693. 874. doi: 10.1016/j.physletb.2026.140195. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 911 forfattere av denne artikkelen] (2026). Evidence for the Collective Nature of Radial Flow in Pb+Pb Collisions with the ATLAS Detector. Physical Review Letters. ISSN 0031-9007. 136(3). doi: 10.1103/ldcn-r2lq. Fulltekst i vitenarkiv
Kłosowski; Piwiński, M.; Linek, A.; Grosbart, M.; Ciuryło, R. & Zawada, M. [Vis alle 64 forfattere av denne artikkelen] (2026). Production of negatively charged atomic ions inside a linear Paul trap for the formation of antiprotonic atoms. Radiation Physics and Chemistry. ISSN 0969-806X. 245. doi: 10.1016/j.radphyschem.2026.113884. Fulltekst i vitenarkiv
Zwalinski, L.; Zou, W.; Zormpa, O.; Zorbas, T. G.; Zoch, K. & Zoccoli, A. [Vis alle 2 908 forfattere av denne artikkelen] (2025). Search for tt¯H/A→tt¯tt¯ production in proton–proton collisions at √s=13 TeV with the ATLAS detector. European Physical Journal C. ISSN 1434-6044. 85(5). doi: 10.1140/epjc/s10052-025-14041-z. Fulltekst i vitenarkiv
Zwalinski, L.; Zou, W.; Zormpa, O.; Zorbas, T. G.; Zoch, K. & Zoccoli, A. [Vis alle 2 919 forfattere av denne artikkelen] (2025). Precision measurement of the B0 meson lifetime using B0→J/ψK∗0 decays with the ATLAS detector. European Physical Journal C. ISSN 1434-6044. 85(7). doi: 10.1140/epjc/s10052-025-14232-8. Fulltekst i vitenarkiv
Zwalinski, L.; Zou, W.; Zormpa, O.; Zorbas, T. G.; Zoch, K. & Zoccoli, A. [Vis alle 2 914 forfattere av denne artikkelen] (2025). A continuous calibration of the ATLAS flavour-tagging classifiers via optimal transportation maps. European Physical Journal C. ISSN 1434-6044. 85(11). doi: 10.1140/epjc/s10052-025-14682-0. Fulltekst i vitenarkiv
Zwalinski, L.; Zormpa, O.; Zorbas, T. G.; Zografos, A.; Zoch, K. & Zoccoli, A. [Vis alle 2 903 forfattere av denne artikkelen] (2025). Search for a new pseudoscalar decaying into a pair of bottom and antibottom quarks in top-associated production in √s=13 TeV proton–proton collisions with the ATLAS detector. European Physical Journal C. ISSN 1434-6044. 85(8). doi: 10.1140/epjc/s10052-025-14507-0. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 887 forfattere av denne artikkelen] (2025). Observation of 𝑉 𝑉 𝑍 production at √𝑠 = 13 TeV with the ATLAS detector. Physics Letters B. ISSN 0370-2693. 866. doi: 10.1016/j.physletb.2025.139527. Fulltekst i vitenarkiv
Zwalinski, L.; Zou, W.; Zormpa, O.; Zorbas, T. G.; Zoch, K. & Zoccoli, A. [Vis alle 2 873 forfattere av denne artikkelen] (2025). Energy scale and resolution for anti-kt jets with radius parameters R=0.2 and 0.6 measured in proton-proton collisions at √s=13 TeV with the ATLAS detector. European Physical Journal C. ISSN 1434-6044. 85(7). doi: 10.1140/epjc/s10052-025-14226-6. Fulltekst i vitenarkiv
Zwalinski, L.; Zou, W.; Zormpa, O.; Zorbas, T. G.; Zoch, K. & Zoccoli, A. [Vis alle 2 918 forfattere av denne artikkelen] (2025). Measurement of W±-boson differential cross-sections in proton–proton collisions with low pile-up data at √s=5.02 TeV and 13TeV with the ATLAS detector. European Physical Journal C. ISSN 1434-6044. 85(7). doi: 10.1140/epjc/s10052-025-14178-x. Fulltekst i vitenarkiv Vis sammendrag
High precision single-differential W ±-boson pro- duction cross-sections as a function of electron or muon transverse momentum pT or their pseudorapity η, as well as double-differential cross-sections as functions of these vari- ables, are measured in proton–proton collisions at centre-of- mass energies √s = 5.02 TeV and 13 TeV. The W -boson charge asymmetry as a function of lepton η is also measured. The data, collected in dedicated runs at reduced instantaneous luminosity with the ATLAS detector at the Large Hadron Collider, correspond to integrated luminosities of 255 pb−1 at 5.02 TeV and 338 pb−1 at 13 TeV. The measurements are in agreement with Standard-Model predictions calculated at next-to-next-to-leading-order in the strong coupling constant αs including transverse-momentum resummation at next-to- next-to-leading logarithmic accuracy using several parton distribution functions. The impact of the measured differen- tial cross-sections as a function of lepton η on the determina- tion of these functions is studied using a profiling technique.
Zwalinski, L.; Zou, W.; Zormpa, O.; Zorbas, T. G.; Zoch, K. & Zoccoli, A. [Vis alle 2 871 forfattere av denne artikkelen] (2025). Improved reconstruction of highly boosted τ-lepton pairs in the ττ→(μνμντ)(hadrons+ντ) decay channels with the ATLAS detector. European Physical Journal C. ISSN 1434-6044. 85(6). doi: 10.1140/epjc/s10052-025-14012-4. Fulltekst i vitenarkiv
Zwalinski, L.; Zou, W.; Zormpa, O.; Zorbas, T. G.; Zoch, K. & Zoccoli, A. [Vis alle 2 926 forfattere av denne artikkelen] (2025). Measurement of the associated production of a top-antitop-quark pair and a Higgs boson decaying into a bb¯ pair in pp collisions at √s=13 TeV using the ATLAS detector at the LHC. European Physical Journal C. ISSN 1434-6044. 85(2). doi: 10.1140/epjc/s10052-025-13740-x. Fulltekst i vitenarkiv
Zwalinski, L.; Zou, W.; Zormpa, O.; Zorbas, T. G.; Zoch, K. & Zoccoli, A. [Vis alle 2 921 forfattere av denne artikkelen] (2025). Reconstruction and identification of pairs of collimated τ-leptons decaying hadronically using √s=13 TeV pp collision data with the ATLAS detector. European Physical Journal C. ISSN 1434-6044. 85(5). doi: 10.1140/epjc/s10052-025-14075-3. Fulltekst i vitenarkiv
Caravita, R.; Campos, S. Alfaro; Auzins, M.; Berghold, M.; Bergmann, B. & Burian, P. [Vis alle 64 forfattere av denne artikkelen] (2025). The AEgIS Experiment: Progress and Future Outlook. Proceedings of Science (PoS). 480. doi: 10.22323/1.480.0024. Fulltekst i vitenarkiv Vis sammendrag
The AEgIS experiment at CERN is pioneering measurements of gravity, spectroscopy, and interferometry using pulsed antimatter atomic sources. This work provides an overview of the AEgIS experimental setup and highlights recent advancements in antihydrogen production, positronium laser cooling, and the creation of antiprotonic atoms. Key technological developments, including the overhaul of the control system and its impact on precision experiments, are reviewed. Future perspectives for AEgIS before CERN Long Shutdown 3 and beyond are summarized.
Camper, Antoine Yves Marie Charles; Campos, S. Alfaro; Auzins, M.; Berghold, M.; Bergmann, B. & Burian, P. [Vis alle 64 forfattere av denne artikkelen] (2025). Positronium laser cooling: results and perspectives. Proceedings of Science (PoS). 480. doi: 10.22323/1.480.0047. Fulltekst i vitenarkiv Vis sammendrag
The experimental demonstration of positronium laser cooling with stationary broadband laser pulses with negative detuning is briefly described. Considerations on the limits of the current experiment and possible future developments follow. In particular, the benefit of positron remoderation, use of a magnetic field, positronium polarization, pulse shaping, coherent laser cooling and deceleration are shortly discussed.
Ferguson, R. C.; Campos, S. Alfaro; Auzins, M.; Berghold, M.; Bergmann, B. & Burian, P. [Vis alle 52 forfattere av denne artikkelen] (2025). Positron-Positronium Converters in Reflection and Transmission Geometry for Gravitational Experiments with Antihydrogen using Moiré Deflectometry. Journal of Physics: Conference Series (JPCS). ISSN 1742-6588. 3029(1). doi: 10.1088/1742-6596/3029/1/012005. Fulltekst i vitenarkiv
Caravita, R.; Campos, S. Alfaro; Auzins, M.; Berghold, M.; Bergmann, B. & Burian, P. [Vis alle 65 forfattere av denne artikkelen] (2025). Laser Cooling Positronium with Broadband Laser Pulses. Journal of Physics: Conference Series (JPCS). ISSN 1742-6588. 3029(1). doi: 10.1088/1742-6596/3029/1/012002. Fulltekst i vitenarkiv Vis sammendrag
The first successful demonstration of broadband laser cooling of positronium (Ps) atoms, obtained within the AEgIS experiment at CERN, is presented here. By employing a custom-designed pulsed alexandrite laser system at 243 nm featuring long-duration pulses of 70 ns and an energy able to saturate the 13S–23P transition over the broad spectrum range of 360 GHz, the temperature of a room-temperature Ps cloud was reduced from 380 K to 170 K in 70 ns. This advancement opens new avenues for precision spectroscopy, antihydrogen production, and fundamental tests with antimatter.
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 915 forfattere av denne artikkelen] (2025). Probing the Higgs boson CP properties in vector-boson fusion production in the H → τ+τ− channel with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2025(10). doi: 10.1007/JHEP10(2025)092. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 924 forfattere av denne artikkelen] (2025). Measurements and interpretations of W±Z production cross-sections in pp collisions at √s=13 TeV with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2025(11). doi: 10.1007/JHEP11(2025)006. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 867 forfattere av denne artikkelen] (2025). An implementation of neural simulation-based inference for parameter estimation in ATLAS. Reports on progress in physics (Print). ISSN 0034-4885. 88(6). doi: 10.1088/1361-6633/add370. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 913 forfattere av denne artikkelen] (2025). Search for emerging jets in pp collisions at √s = 13.6 TeV with the ATLAS experiment. Reports on progress in physics (Print). ISSN 0034-4885. 88(9). doi: 10.1088/1361-6633/adfe17. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 874 forfattere av denne artikkelen] (2025). Configuration, Performance, and Commissioning of the ATLAS b-jet Triggers for the 2022 and 2023 LHC data-taking periods. Journal of Instrumentation (JINST). 20(3). doi: 10.1088/1748-0221/20/03/P03002. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 863 forfattere av denne artikkelen] (2025). Measurement of off-shell Higgs boson production in the H∗ → ZZ → 4ℓ decay channel using a neural simulation-based inference technique in 13 TeV pp collisions with the ATLAS detector. Reports on progress in physics (Print). ISSN 0034-4885. 88(5). doi: 10.1088/1361-6633/adcd9a. Fulltekst i vitenarkiv
Aad, G.; Abbott, B.; Abeling, K.; Abicht, N. J.; Abidi, S. H. & Aboulhorma, A. [Vis alle 2 924 forfattere av denne artikkelen] (2025). Measurements of W+W−production cross-sections in pp collisions at s=13 TeV with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2025(8). doi: 10.1007/JHEP08(2025)142. Fulltekst i vitenarkiv Vis sammendrag
Measurements of W+W− → e±νμ∓ν production cross-sections are presented, providing a test of the predictions of perturbative quantum chromodynamics and the electroweak theory. The measurements are based on data from pp collisions at √s = 13 TeV recorded by the ATLAS detector at the Large Hadron Collider in 2015–2018, corresponding to an integrated luminosity of 140 fb−1. The number of events due to top-quark pair production, the largest background, is reduced by rejecting events containing jets with b-hadron decays. An improved methodology for estimating the remaining top-quark background enables a precise measurement of W+W− cross-sections with no additional requirements on jets. The fiducial W+W− cross-section is determined in a maximum-likelihood fit with an uncertainty of 3.1%. The measurement is extrapolated to the full phase space, resulting in a total W+W− cross-section of 127 ± 4 pb. Differential cross-sections are measured as a function of twelve observables that comprehensively describe the kinematics of W+W− events. The measurements are compared with state-of-the-art theory calculations and excellent agreement with predictions is observed. A charge asymmetry in the lepton rapidity is observed as a function of the dilepton invariant mass, in agreement with the Standard Model expectation. A CP-odd observable is measured to be consistent with no CP violation. Limits on Standard Model effective field theory Wilson coefficients in the Warsaw basis are obtained from the differential cross-sections.
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 883 forfattere av denne artikkelen] (2025). Measurement of tt¯ production in association with additional b-jets in the eμ final state in proton–proton collisions at √s = 13 TeV with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2025(1). doi: 10.1007/JHEP01(2025)068. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 874 forfattere av denne artikkelen] (2025). Cross-section measurements for the production of a W-boson in association with high-transverse-momentum jets in pp collisions at √s = 13 TeV with the ATLAS detector. European Physical Journal C. ISSN 1434-6044. 85(7). doi: 10.1140/epjc/s10052-025-14078-0. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 909 forfattere av denne artikkelen] (2025). Evidence for Longitudinally Polarized W Bosons in the Electroweak Production of Same-Sign W Boson Pairs in Association with Two Jets in pp Collisions at √s = 13 TeV with the ATLAS Detector. Physical Review Letters. ISSN 0031-9007. 135(11). doi: 10.1103/bpln-ccql. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 946 forfattere av denne artikkelen] (2025). Measurements of the production cross-sections of a Higgs boson in association with a vector boson and decaying into WW∗ with the ATLAS detector at √s = 13 TeV. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2025(8). doi: 10.1007/JHEP08(2025)034. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 889 forfattere av denne artikkelen] (2025). Differential cross-section measurements of Higgs boson production in the H→τ+τ− decay channel in pp collisions at √s = 13 TeV with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2025(3). doi: 10.1007/JHEP03(2025)010. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 933 forfattere av denne artikkelen] (2025). Differential cross-section measurements of D± and D±s meson production in proton-proton collisions at √s = 13 TeV with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2025(7). doi: 10.1007/JHEP07(2025)086. Fulltekst i vitenarkiv
Aad, G.; Abbott, B.; Abeling, K.; Abicht, N. J.; Abidi, S. H. & Aboulhorma, A. [Vis alle 2 877 forfattere av denne artikkelen] (2025). Search for diphoton resonances in the 66 to 110 GeV mass range using pp collisions at (Formula presented.) TeV with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2025(1). doi: 10.1007/JHEP01(2025)053. Fulltekst i vitenarkiv Vis sammendrag
A search is performed for light, spin-0 bosons decaying into two photons in the 66 to 110 GeV mass range, using 140 fb−1 of proton-proton collisions at √s = 13 TeV produced by the Large Hadron Collider and collected by the ATLAS detector. Multivariate analysis techniques are used to define event categories that improve the sensitivity to new resonances beyond the Standard Model. A model-independent search for a generic spin-0 particle and a model-dependent search for an additional low-mass Higgs boson are performed in the diphoton invariant mass spectrum. No significant excess is observed in either search. Mass-dependent upper limits at the 95% confidence level are set in the model-independent scenario on the fiducial cross-section times branching ratio into two photons in the range of 8 fb to 53 fb. Similarly, in the model-dependent scenario upper limits are set on the total cross-section times branching ratio into two photons as a function of the Higgs boson mass in the range of 19 fb to 102 fb.
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 898 forfattere av denne artikkelen] (2025). Searches for direct slepton production in the compressed-mass corridor in √s = 13 TeV pp collisions with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2025(8). doi: 10.1007/JHEP08(2025)053. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 920 forfattere av denne artikkelen] (2025). Measurement of the top quark mass with the ATLAS detector using tt¯ events with a high transverse momentum top quark. Physics Letters B. ISSN 0370-2693. 867. doi: 10.1016/j.physletb.2025.139608. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 830 forfattere av denne artikkelen] (2025). Search for Higgs boson decays into a pair of pseudoscalar particles in the γγτhadτhad final state using pp collisions at √s = 13 TeV with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2025(3). doi: 10.1007/JHEP03(2025)190. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 914 forfattere av denne artikkelen] (2025). A measurement of the high-mass ττ¯ production cross-section at √s = 13 TeV with the ATLAS detector and constraints on new particles and couplings. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2025(10). doi: 10.1007/JHEP10(2025)054. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 885 forfattere av denne artikkelen] (2025). Observation of 𝑡⁢ ¯ 𝑡 Production in Pb+Pb Collisions at √𝑠NN=5.02 TeV with the ATLAS Detector. Physical Review Letters. ISSN 0031-9007. 134(14). doi: 10.1103/PhysRevLett.134.142301. Fulltekst i vitenarkiv
Aad, G.; Abbott, B.; Abeling, K.; Abicht, N. J.; Abidi, S. H. & Aboulhorma, A. [Vis alle 2 925 forfattere av denne artikkelen] (2025). Search for a new scalar decaying into new spin-1 bosons in four-lepton final states with the ATLAS detector. Physics Letters B. ISSN 0370-2693. 865. doi: 10.1016/j.physletb.2025.139472. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 942 forfattere av denne artikkelen] (2025). Search for the jet-induced diffusion wake in the quark-gluon plasma via measurements of jet-track correlations in photon-jet events in Pb + Pb collisions at √𝑠𝑁⁢𝑁 = 5.02TeV with the ATLAS detector. Physical Review C. ISSN 2469-9985. 111(4). doi: 10.1103/PhysRevC.111.044909. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 887 forfattere av denne artikkelen] (2025). Search for the associated production of charm quarks and a Higgs boson decaying into a photon pair with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2025(2). doi: 10.1007/JHEP02(2025)045. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 867 forfattere av denne artikkelen] (2025). Search for charged Higgs bosons produced in top-quark decays or in association with top quarks and decaying via 𝐻± →𝜏±⁢𝜈𝜏 in 13 TeV 𝑝⁢𝑝 collisions with the ATLAS detector. Physical Review D. ISSN 2470-0010. 111(7). doi: 10.1103/PhysRevD.111.072006. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 922 forfattere av denne artikkelen] (2025). Search for the production of a Higgs boson in association with a single top quark in pp collisions at √s=13 TeV with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2025(10). doi: 10.1007/JHEP10(2025)093. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 876 forfattere av denne artikkelen] (2025). Search for boosted low-mass resonances decaying into hadrons produced in association with a photon in pp collisions at √s = 13 TeV with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2025(1). doi: 10.1007/JHEP01(2025)099. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 927 forfattere av denne artikkelen] (2025). Measurement of jet track functions in pp collisions at √s=13 TeV with the ATLAS detector. Physics Letters B. ISSN 0370-2693. 868. doi: 10.1016/j.physletb.2025.139680. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 826 forfattere av denne artikkelen] (2025). Search for a heavy charged Higgs boson decaying into a W boson and a Higgs boson in final states with leptons and b-jets in √s = 13 TeV pp collisions with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2025(2). doi: 10.1007/JHEP02(2025)143. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 882 forfattere av denne artikkelen] (2025). Search for vector-like leptons coupling to first- and second-generation Standard Model leptons in pp collisions at √s = 13 TeV with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2025(5). doi: 10.1007/JHEP05(2025)075. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 920 forfattere av denne artikkelen] (2025). Test of lepton flavour universality in W-boson decays into electrons and τ-leptons using pp collisions at √s = 13 TeV with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2025(5). doi: 10.1007/JHEP05(2025)038. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 876 forfattere av denne artikkelen] (2025). Search for same-charge top-quark pair production in pp collisions at √s = 13 TeV with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2025(2). doi: 10.1007/JHEP02(2025)084. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abeling, K.; Abicht, N. J. & Abidi, S. H. [Vis alle 2 880 forfattere av denne artikkelen] (2025). The performance of missing transverse momentum reconstruction and its significance with the ATLAS detector using 140 fb-1 of √s=13 TeV pp collisions. European Physical Journal C. ISSN 1434-6044. 85(6). doi: 10.1140/epjc/s10052-025-14062-8. Fulltekst i vitenarkiv
Zwalinski, L.; Zou, W.; Zormpa, O.; Zorbas, T. G.; Zoch, K. & Zoccoli, A. [Vis alle 2 903 forfattere av denne artikkelen] (2025). Total Cost of Ownership and Evaluation of Google Cloud Resources for the ATLAS Experiment at the LHC. Computing and Software for Big Science. ISSN 2510-2036. 9(1). doi: 10.1007/s41781-024-00128-x. Fulltekst i vitenarkiv Vis sammendrag
The ATLAS Google Project was established as part of an ongoing evaluation of the use of commercial clouds by the ATLAS Collaboration, in anticipation of the potential future adoption of such resources by WLCG grid sites to fulfil or complement their computing pledges. Seamless integration of Google cloud resources into the worldwide ATLAS distributed computing infrastructure was achieved at large scale and for an extended period of time, and hence cloud resources are shown to be an effective mechanism to provide additional, flexible computing capacity to ATLAS. For the first time a total cost of ownership analysis has been performed, to identify the dominant cost drivers and explore effective mechanisms for cost control. Network usage significantly impacts the costs of certain ATLAS workflows, underscoring the importance of implementing such mechanisms. Resource bursting has been successfully demonstrated, whilst exposing the true cost of this type of activity. A follow-up to the project is underway to investigate methods for improving the integration of cloud resources in data-intensive distributed computing environments and reducing costs related to network connectivity, which represents the primary expense when extensively utilising cloud resources.
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 923 forfattere av denne artikkelen] (2025). A search for dark matter produced in association with a dark Higgs boson decaying into a Higgs boson pair in 3b or 4b final states using pp collisions at √s = 13 TeV with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2025(9). doi: 10.1007/JHEP09(2025)067. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 901 forfattere av denne artikkelen] (2025). Search for heavy neutral leptons in decays of W bosons using leptonic and semi-leptonic displaced vertices in √s = 13 TeV pp collisions with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2025(7). doi: 10.1007/JHEP07(2025)196. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 905 forfattere av denne artikkelen] (2025). Measurement of double-differential charged-current Drell-Yan cross-sections at high transverse masses in pp collisions at √s = 13 TeV with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2025(7). doi: 10.1007/JHEP07(2025)026. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 892 forfattere av denne artikkelen] (2025). Measurements of WH and ZH production with Higgs boson decays into bottom quarks and direct constraints on the charm Yukawa coupling in 13 TeV pp collisions with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2025(4). doi: 10.1007/JHEP04(2025)075. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 903 forfattere av denne artikkelen] (2025). Search for long-lived charged particles using large specific ionisation loss and time of flight in 140 fb−1 of pp collisions at √s = 13 TeV with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2025(7). doi: 10.1007/JHEP07(2025)140. Fulltekst i vitenarkiv
Zwalinski, L.; Zou, W.; Zormpa, O.; Zorbas, T. G.; Zoch, K. & Zoccoli, A. [Vis alle 2 925 forfattere av denne artikkelen] (2025). A precise measurement of the jet energy scale derived from single-particle measurements and in situ techniques in proton–proton collisions at √s = 13 TeV with the ATLAS detector. European Physical Journal C. ISSN 1434-6044. 85(9). doi: 10.1140/epjc/s10052-025-14409-1. Fulltekst i vitenarkiv
Zwalinski, L.; Zormpa, O.; Zorbas, T. G.; Zografos, A.; Zoch, K. & Zoccoli, A. [Vis alle 2 902 forfattere av denne artikkelen] (2025). Search for electroweak production of vector-like leptons in τ-lepton and b-jet final states in pp collisions at √s = 13 TeV with the ATLAS detector. European Physical Journal C. ISSN 1434-6044. 85(11). doi: 10.1140/epjc/s10052-025-14748-z. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 931 forfattere av denne artikkelen] (2025). Evidence for the Dimuon Decay of the Higgs Boson in 𝑝⁢𝑝 Collisions with the ATLAS Detector. Physical Review Letters. ISSN 0031-9007. 135(23). doi: 10.1103/gzdh-p159. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 916 forfattere av denne artikkelen] (2025). Observation of double parton scattering in same-sign W boson pair production in pp collisions at s=13 TeV with the ATLAS detector. Physics Letters B. ISSN 0370-2693. 870. doi: 10.1016/j.physletb.2025.139892. Fulltekst i vitenarkiv Vis sammendrag
This letter reports the measurement of double parton scattering in same-sign W boson pair production with the ATLAS detector. The data set used corresponds to an integrated luminosity of 140 fb−1 of proton–proton collisions at a center-of-mass energy of 13 TeV, collected during Run 2 of the Large Hadron Collider. The study is performed in final states including two same-charge leptons, electron or muon, missing transverse momentum, and up to one jet. An excess of events is observed over the expected background contributions with a significance of 8.8 standard deviations. The measured fiducial cross section times leptonic branching fraction is 4.59 ± 0.64 fb. The measurement corresponds to a double parton scattering effective cross section of 10.6 ± 1.8 mb.
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 909 forfattere av denne artikkelen] (2025). Constraining off-shell Higgs boson production and the Higgs boson total width using WW → ℓνℓν final states with the ATLAS detector. Physics Letters B. ISSN 0370-2693. 870. doi: 10.1016/j.physletb.2025.139898. Fulltekst i vitenarkiv
Aad, G.; Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S. & Abeling, K. [Vis alle 2 924 forfattere av denne artikkelen] (2025). Search for electroweak-scale dijet resonances using trigger-level analysis with the ATLAS detector in 132 fb− 1 of pp collisions at √s = 13 TeV. Physical Review D. ISSN 2470-0010. 112(9). doi: 10.1103/15p2-bkg8. Fulltekst i vitenarkiv
Aad, G.; Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S. & Abeling, K. [Vis alle 2 902 forfattere av denne artikkelen] (2025). Search for events with one displaced vertex from long-lived neutral particles decaying into hadronic jets in the ATLAS muon spectrometer in 𝑝⁢𝑝 collisions at √𝑠 = 13 TeV. Physical Review D. ISSN 2470-0010. 112(9). doi: 10.1103/cmql-s9sq. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 2 914 forfattere av denne artikkelen] (2025). Measurement of substructure-dependent suppression of large-radius jets with charged particles in Pb+Pb collisions with ATLAS. Physics Letters B. ISSN 0370-2693. 871. doi: 10.1016/j.physletb.2025.139929. Fulltekst i vitenarkiv
Zwalinski, L.; Zormpa, O.; Zorbas, T. G.; Zografos, A.; Zoch, K. & Zoccoli, A. [Vis alle 2 910 forfattere av denne artikkelen] (2025). Measurements of Higgs boson production via gluon–gluon fusion and vector-boson fusion using H→WW∗→ℓνℓν decays in pp collisions with the ATLAS detector and their effective field theory interpretations. European Physical Journal C. ISSN 1434-6044. 85(12). doi: 10.1140/epjc/s10052-025-14761-2. Fulltekst i vitenarkiv
Rienäcker, Benjamin; Campos, S. Alfaro; Auzins, M.; Berghold, M.; Bergmann, B. & Burian, P. [Vis alle 64 forfattere av denne artikkelen] (2025). Prospects for forward emitted positronium from nanoporous membranes at AEgIS. Proceedings of Science (PoS). 480. doi: 10.22323/1.480.0082. Fulltekst i vitenarkiv
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 51 forfattere av denne artikkelen] (2025). Search for light neutral particles decaying promptly into collimated pairs of electrons or muons in pp collisions at √s = 13 Te V with the ATLAS detector. European Physical Journal C. ISSN 1434-6044. doi: 10.1140/epjc/s10052-025-13916-5. Fulltekst i vitenarkiv Vis sammendrag
A search for a dark photon, a new light neutral particle, which decays promptly into collimated pairs of electrons or muons is presented. The search targets dark photons resulting from the exotic decay of the Standard Model Higgs boson, assuming its production via the dominant gluon-gluon fusion mode. The analysis is based on 140 fb - 1 of data collected with the ATLAS detector at the Large Hadron Collider from proton-proton collisions at a center-of-mass energy of 13 Te V . Events with collimated pairs of electrons or muons are analysed and background contributions are estimated using data-driven techniques. No significant excess in the data above the Standard Model background is observed. Upper limits are set at 95% confidence level on the branching ratio of the Higgs boson decay into dark photons between 0.001% and 5%, depending on the assumed dark photon mass and signal model.
Aad, G.; Aakvaag, Erlend; Abbott, B.; Abdelhameed, S.; Abeling, K. & Abicht, N. J. [Vis alle 50 forfattere av denne artikkelen] (2025). Measurement of the Lund jet plane in hadronic decays of top quarks and W bosons with the ATLAS detector. European Physical Journal C. ISSN 1434-6044. 85. doi: 10.1140/epjc/s10052-025-13924-5. Fulltekst i vitenarkiv Vis sammendrag
The Lund jet plane (LJP) is measured for the first time in t t ¯ events, using 140 fb - 1 of s = 13 TeV pp collision data collected with the ATLAS detector at the LHC. The LJP is a two-dimensional observable of the sub-structure of hadronic jets that acts as a proxy for the kinematics of parton showers and hadron formation. The observable is constructed from charged particles and is measured for R = 1.0 anti- k t jets with transverse momentum above 350 GeV containing the full decay products of either a top quark or a daughter W boson. The other top quark in the event is identified from its decay into a b-quark, an electron or a muon and a neutrino. The measurement is corrected for detector effects and compared with a range of Monte Carlo predictions sensitive to different aspects of the hadronic decays of the heavy particles. In the W-boson-initiated jets, all the predictions are incompatible with the measurement. In the top quark initiated jets, disagreement with all predictions is observed in smaller subregions of the plane, and with a subset of the predictions across the fiducial plane. The measurement could be used to improve the tuning of Monte Carlo generators, for better modelling of hadronic decays of heavy quarks and bosons, or to improve the performance of jet taggers.
Zwalinski, L.; Zou, W.; Zormpa, O.; Zorbas, T. G.; Zoch, K. & Zoccoli, A. [Vis alle 2 911 forfattere av denne artikkelen] (2025). Estimation of backgrounds from jets misidentified as τ-leptons using the Universal Fake Factor method with the ATLAS detector. European Physical Journal C. ISSN 1434-6044. 85(12). doi: 10.1140/epjc/s10052-025-14916-1. Fulltekst i vitenarkiv
Zwalinski, L.; Zormpa, O.; Zorbas, T. G.; Zografos, A.; Zoch, K. & Zoccoli, A. [Vis alle 2 935 forfattere av denne artikkelen] (2025). Search for squarks and gluinos in pp collisions at √s = 13 TeV and 13.6 TeV in events with τ-leptons, jets and missing transverse momentum using the ATLAS detector. European Physical Journal C. ISSN 1434-6044. 85(12). doi: 10.1140/epjc/s10052-025-14957-6. Fulltekst i vitenarkiv
Zwalinski, L.; Zormpa, O.; Zorbas, T. G.; Zografos, A.; Zoch, K. & Zoccoli, A. [Vis alle 2 914 forfattere av denne artikkelen] (2025). Measurement of high-mass tt¯ℓ+ℓ- production and lepton flavour universality-inspired effective field theory interpretations at √s=13 TeV with the ATLAS detector. European Physical Journal C. ISSN 1434-6044. 85(12). doi: 10.1140/epjc/s10052-025-14695-9. Fulltekst i vitenarkiv

Se alle arbeider i NVA

Aad, G.; Abbott, B.; Abbott, D. C.; Abeling, K.; Abidi, S. H. & Aboulhorma, A. [Vis alle 2 906 forfattere av denne artikkelen] (2025). Erratum: Search for boosted diphoton resonances in the 10 to 70 GeV mass range using 138 fb−1 of 13 TeV pp collisions with the ATLAS detector. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2025(12). doi: 10.1007/JHEP12(2025)143. Fulltekst i vitenarkiv
Lunde, Jenny; Sandaker, Heidi & Pernegger, Heinz (2026). ATLAS Inner Tracker and Monolithic Sensors for future applications. Universitetet i Oslo. Fulltekst i vitenarkiv Vis sammendrag
Future collider experiments will require trackers that can handle high luminosity environments. The requirements for future trackers include high spatial and temporal resolution, low material budget, radiation hardness and low power consumption. The High-Luminosity LHC is expected to start during the summer of 2030, and is expected to deliver an integrated luminosity up to 4000 fb−1 over 10 years of operation. In preparation for the increased luminosity, ATLAS will replace its current tracker, the Inner Detector, with a new all-silicon tracker called the Inner Tracker (ITk). The work presented in this thesis addresses the development of detectors for high luminosity environments, including testing and production of modules for the ITk, as well as developments for a monolithic sensor with internal amplification. During the time of operation, the ITk detector can undergo large temperature variations, in case of power or cooling failures. The bump bond connections of hybrid pixel detectors need to be able to withstand the thermal stress due to differences in thermal expansion coefficients between the detector materials. To ensure the robustness of the bump bonds, a thermal cycling campaign was conducted, with an overestimation of the temperature variations and number of cycles expected for the lifetime of the ITk detector. After 100 thermal cycles, none of the modules showed a significant increase in disconnected bump bonds. The study led to the qualification of the hybridization vendors, which was needed to start full scale production of planar detector modules for ITk. To cope with high pile-up in high-luminosity environments, timing information is becoming increasingly important. The CMOS Active SenSor with Internal Amplification (CASSIA) project aims to develop a monolithic sensor with gain, to be used for time tagging or 4D tracking, where temporal resolution within a bunch crossing is added to the 3 spatial tracking dimensions. The monolithic implementation may allow for a low material budget and low power consumption, while the internal amplification gives improved timing resolution, with an aim of reaching below 100 ps timing resolution. Initial measurements and simulations of CASSIA will be presented, with a focus on gain characteristics, breakdown mechanisms and dark count rate. Different sensor design parameters, including variations in electrode and gain layer implantation, are studied to see how they affect the sensor performance. The work presents developments of pixel detectors for high luminosity collider experiments, from conceptualization and prototyping, to testing, verification and production of detector modules.