The Forward Search Experiment (FASER) at CERN's Large Hadron Collider (LHC) has recently directly detected the first collider neutrinos. Neutrinos play an important role in all FASER analyses, either ...as signal or background, and it is therefore essential to understand the neutrino event rates. In this study, we update previous simulations and present prescriptions for theoretical predictions of neutrino fluxes and cross sections, together with their associated uncertainties. With these results, we discuss the potential for possible measurements that could be carried out in the coming years with the FASER neutrino data to be collected in LHC Run 3 and Run 4.
This paper presents the first results of the study of high-energy electron
and muon neutrino charged-current interactions in the FASER$\nu$
emulsion/tungsten detector of the FASER experiment at the ...LHC. A subset of the
FASER$\nu$ volume, which corresponds to a target mass of 128.6~kg, was exposed
to neutrinos from the LHC $pp$ collisions with a centre-of-mass energy of
13.6~TeV and an integrated luminosity of 9.5 fb$^{-1}$. Applying stringent
selections requiring electrons with reconstructed energy above 200~GeV, four
electron neutrino interaction candidate events are observed with an expected
background of $0.025^{+0.015}_{-0.010}$, leading to a statistical significance
of 5.2$\sigma$. This is the first direct observation of electron neutrino
interactions at a particle collider. Eight muon neutrino interaction candidate
events are also detected, with an expected background of
$0.22^{+0.09}_{-0.07}$, leading to a statistical significance of 5.7$\sigma$.
The signal events include neutrinos with energies in the TeV range, the
highest-energy electron and muon neutrinos ever detected from an artificial
source. The energy-independent part of the interaction cross section per
nucleon is measured over an energy range of 560--1740 GeV (520--1760 GeV) for
$\nu_e$ ($\nu_{\mu}$) to be $(1.2_{-0.7}^{+0.8}) \times
10^{-38}~\mathrm{cm}^{2}\,\mathrm{GeV}^{-1}$ ($(0.5\pm0.2) \times
10^{-38}~\mathrm{cm}^{2}\,\mathrm{GeV}^{-1}$), consistent with Standard Model
predictions. These are the first measurements of neutrino interaction cross
sections in those energy ranges.
This paper presents the first results of the study of high-energy electron and muon neutrino charged-current interactions in the FASER\(\nu\) emulsion/tungsten detector of the FASER experiment at the ...LHC. A subset of the FASER\(\nu\) volume, which corresponds to a target mass of 128.6~kg, was exposed to neutrinos from the LHC \(pp\) collisions with a centre-of-mass energy of 13.6~TeV and an integrated luminosity of 9.5 fb\(^{-1}\). Applying stringent selections requiring electrons with reconstructed energy above 200~GeV, four electron neutrino interaction candidate events are observed with an expected background of \(0.025^{+0.015}_{-0.010}\), leading to a statistical significance of 5.2\(\sigma\). This is the first direct observation of electron neutrino interactions at a particle collider. Eight muon neutrino interaction candidate events are also detected, with an expected background of \(0.22^{+0.09}_{-0.07}\), leading to a statistical significance of 5.7\(\sigma\). The signal events include neutrinos with energies in the TeV range, the highest-energy electron and muon neutrinos ever detected from an artificial source. The energy-independent part of the interaction cross section per nucleon is measured over an energy range of 560--1740 GeV (520--1760 GeV) for \(\nu_e\) (\(\nu_{\mu}\)) to be \((1.2_{-0.7}^{+0.8}) \times 10^{-38}~\mathrm{cm}^{2}\,\mathrm{GeV}^{-1}\) (\((0.5\pm0.2) \times 10^{-38}~\mathrm{cm}^{2}\,\mathrm{GeV}^{-1}\)), consistent with Standard Model predictions. These are the first measurements of neutrino interaction cross sections in those energy ranges.
Deficits of working memory (WM) are recognized as an important pathological feature in schizophrenia. Since the P600 component of event related potentials has been hypothesized that represents ...aspects of second-pass parsing processes of information processing, and is related to WM, the present study focuses on P600 elicited during a WM test in drug-naive first-episode schizophrenics (FES) compared to healthy controls. We examined 16 drug-naive first-episode schizophrenic patients and 23 healthy controls matched for age and sex. Compared with controls schizophrenic patients showed reduced P600 amplitude on left temporoparietal region and increased P600 amplitude on left occipital region. With regard to the latency, the patients exhibited significantly prolongation on right temporoparietal region. The obtained pattern of differences classified correctly 89.20% of patients. Memory performance of patients was also significantly impaired relative to controls. Our results suggest that second-pass parsing process of information processing, as indexed by P600, elicited during a WM test, is impaired in FES. Moreover, these findings lend support to the view that the auditory WM in schizophrenia involves or affects a circuitry including temporoparietal and occipital brain areas.
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