# Preprints

 2020-06-2915:01 [PUBDB-2020-02516] Preprint Gharibyan, V. Explaining the Universe with gravitation dependent quantum vacuum [20-110] Recent experimental hints for the equivalence principle violation point to an effective vacuum polarization in gravitational fields.This will change vacuum properties altering magnitudes of the physical constants. Here I discuss how a variable Planck constant and light speed, modified by gravity, can explain the main cosmological observations without invoking the space expansion.The obtained results are suggesting a simplified Universe without theBig-Bang, Dark Energy or Dark Matter, pointing to gravitationally excited quantum vacuum as the source of the Cosmic Microwave Background.. Restricted: PDF PDF (PDFA); 2020-06-2914:26 [PUBDB-2020-02514] Preprint et al Search for Higgs boson decays into two new low-mass spin-0 particles in the 4$b$ channel with the ATLAS detector using $pp$ collisions at $\sqrt{s}= 13$ TeV [CERN-EP-2020-067; arXiv:2005.12236] This paper describes a search for beyond the Standard Model decays of the Higgs boson into a pair of new spin-0 particles subsequently decaying into $b$-quark pairs, $H \rightarrow aa \rightarrow (b\bar{b})(b\bar{b})$, using proton-proton collision data collected by the ATLAS detector at the Large Hadron Collider at center-of-mass energy $\sqrt{s}=13$ TeV. This search focuses on the regime where the decay products are collimated and in the range $15 \leq m_a \leq 30$ GeV and is complementary to a previous search in the same final state targeting the regime where the decay products are well separated and in the range $20 \leq m_a \leq 60$ GeV. [...] Restricted: PDF PDF (PDFA); 2020-06-2913:37 [PUBDB-2020-02512] Preprint et al Search for new non-resonant phenomena in high-mass dilepton final states with the ATLAS detector [CERN-EP-2020-066; arXiv:2006.12946] A search for new physics with non-resonant signals in dielectron and dimuon final states in the mass range above 2 TeV is presented. This is the first search for non-resonant signals in dilepton final states at the LHC to use a background estimate from the data. [...] Restricted: PDF PDF (PDFA); 2020-06-2512:13 [PUBDB-2020-02475] Preprint et al Measurement of the $t\bar{t}$ production cross-section in the lepton+jets channel at $\sqrt{s}=13\;$TeV with the ATLAS experiment [CERN-EP-2020-096; arXiv:2006.13076]   The $t\bar{t}$ production cross-section is measured in the lepton+jets channel using proton$-$proton collision data at a centre-of-mass energy of $\sqrt{s}=13$ TeV collected with the ATLAS detector at the LHC. The dataset corresponds to an integrated luminosity of 139 fb$^{-1}$. [...] OpenAccess: PDF PDF (PDFA); 2020-06-2212:36 [PUBDB-2020-02442] Preprint et al Search for $t\bar{t}$ resonances in fully hadronic final states in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector [CERN-EP-2020-055; arXiv:2005.05138] This paper presents a search for new heavy particles decaying into a pair of top quarks using 139 fb$^{-1}$ of proton$-$proton collision data recorded at a centre-of-mass energy of $\sqrt{s}=13$ TeV with the ATLAS detector at the Large Hadron Collider. The search is performed using events consistent with pair production of high-transverse-momentum top quarks and their subsequent decays into the fully hadronic final states. [...] Restricted: PDF PDF (PDFA); 2020-06-2210:15 [PUBDB-2020-02439] Preprint et al Dijet resonance search with weak supervision using $\sqrt{s}=13$ TeV $pp$ collisions in the ATLAS detector [CERN-EP-2020-062; arXiv:2005.02983] This Letter describes a search for resonant new physics using a machine-learning anomaly detection procedure that does not rely on a signal model hypothesis. Weakly supervised learning is used to train classifiers directly on data to enhance potential signals. [...] Restricted: PDF PDF (PDFA); 2020-06-2210:10 [PUBDB-2020-02438] Preprint Moch, S. Heavy-flavor PDF evolution and variable-flavor number scheme uncertainties in deep-inelastic scattering [DESY-20-061; DO-TH 20/05; SAGEX-20-09; arXiv:2006.07032] We consider a detailed account on the construction of the heavy-quark parton distribution functions for charm and bottom, starting from $n_f=3$ light flavors in the fixed-flavor number (FFN) scheme and by using the standard decoupling relations for heavy quarks in QCD. We also account for two-mass effects. [...] Restricted: PDF PDF (PDFA); 2020-06-1910:23 [PUBDB-2020-02411] Preprint et al Microscopic force for aerosol transport [arXiv:2006.10652]   A key ingredient for single particle diffractive imaging experiments is the successful and efficient delivery of sample. Current sample-delivery methods are based on aerosol injectors in which the samples are driven by fluid-dynamic forces. [...] OpenAccess: PDF PDF (PDFA); 2020-06-1815:05 [PUBDB-2020-02409] Preprint et al Search for heavy diboson resonances in semileptonic final states in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector [CERN-EP-2020-049; arXiv:2004.14636]   This paper reports on a search for heavy resonances decaying into $WW$, $ZZ$ or $WZ$ using proton-proton collision data at a centre-of-mass energy of $\sqrt{s}=13$ TeV. The data, corresponding to an integrated luminosity of 139 $\mathrm{fb^{-1}}$, were recorded with the ATLAS detector from 2015 to 2018 at the Large Hadron Collider. [...] OpenAccess: PDF PDF (PDFA); 2020-06-1814:35 [PUBDB-2020-02408] Preprint et al Search for a scalar partner of the top quark in the all-hadronic $t\bar{t}$ plus missing transverse momentum final state at $\sqrt{s}$=13 TeV with the ATLAS detector [CERN-EP-2020-044; arXiv:2004.14060]   A search for direct pair production of scalar partners of the top quark (top squarks or scalar third-generation up-type leptoquarks) in the all-hadronic $t\bar{t}$ plus missing transverse momentum final state is presented. The analysis of 139 fb$^{-1}$ of $\sqrt{s}$=13 TeV proton-proton collision data collected using the ATLAS detector at the LHC yields no significant excess over the Standard Model background expectation. [...] OpenAccess: PDF PDF (PDFA);