The article discusses pathogenesis and treatment of COVID-19. The authors presented state-of-the-art insight into hemostatic disorders in patients with COVID-19 and clinical recommendations on ...prevention of thrombosis and thromboembolism in patients infected with SARS-CoV-2. The article discussed in detail a new hypothesis proposed by Chinese physicians about a new component in the pathogenesis of COVID-19, namely, about the effect of SARS-CoV-2 virus on the hemoglobin beta-chain and the formation of a complex with porphyrin, which results in displacement of the iron ion. Thus, hemoglobin loses the capability for transporting oxygen, which aggravates hypoxia and worsens the prognosis. The article stated rules of hemotransfusion safety in the conditions of COVID-19 pandemic.
The reconstruction of the signal from hadrons and jets emerging from the proton–proton collisions at the Large Hadron Collider (LHC) and entering the ATLAS calorimeters is based on a ...three-dimensional topological clustering of individual calorimeter cell signals. The cluster formation follows cell signal-significance patterns generated by electromagnetic and hadronic showers. In this, the clustering algorithm implicitly performs a topological noise suppression by removing cells with insignificant signals which are not in close proximity to cells with significant signals. The resulting
topological cell clusters
have shape and location information, which is exploited to apply a local energy calibration and corrections depending on the nature of the cluster. Topological cell clustering is established as a well-performing calorimeter signal definition for jet and missing transverse momentum reconstruction in ATLAS.
The jet energy scale (JES) and its systematic uncertainty are determined for jets measured with the ATLAS detector using proton–proton collision data with a centre-of-mass energy of
s
=
7
TeV ...corresponding to an integrated luminosity of
4.7
fb
-
1
. Jets are reconstructed from energy deposits forming topological clusters of calorimeter cells using the anti-
k
t
algorithm with distance parameters
R
=
0.4
or
R
=
0.6
, and are calibrated using MC simulations. A residual JES correction is applied to account for differences between data and MC simulations. This correction and its systematic uncertainty are estimated using a combination of in situ techniques exploiting the transverse momentum balance between a jet and a reference object such as a photon or a
Z
boson, for
20
≤
p
T
jet
<
1000
GeV
and pseudorapidities
|
η
|
<
4.5
. The effect of multiple proton–proton interactions is corrected for, and an uncertainty is evaluated using in situ techniques. The smallest JES uncertainty of less than 1 % is found in the central calorimeter region (
|
η
|
<
1.2
) for jets with
55
≤
p
T
jet
<
500
GeV
. For central jets at lower
p
T
, the uncertainty is about 3 %. A consistent JES estimate is found using measurements of the calorimeter response of single hadrons in proton–proton collisions and test-beam data, which also provide the estimate for
p
T
jet
>
1
TeV. The calibration of forward jets is derived from dijet
p
T
balance measurements. The resulting uncertainty reaches its largest value of 6 % for low-
p
T
jets at
|
η
|
=
4.5
. Additional JES uncertainties due to specific event topologies, such as close-by jets or selections of event samples with an enhanced content of jets originating from light quarks or gluons, are also discussed. The magnitude of these uncertainties depends on the event sample used in a given physics analysis, but typically amounts to 0.5–3 %.
A search for scalar particles decaying via narrow resonances into two photons in the mass range 65-600 GeV is performed using 20.3 fb(-1) of √s 8 TeV pp collision data collected with the ATLAS ...detector at the Large Hadron Collider. The recently discovered Higgs boson is treated as a background. No significant evidence for an additional signal is observed. The results are presented as limits at the 95% confidence level on the production cross section of a scalar boson times branching ratio into two photons, in a fiducial volume where the reconstruction efficiency is approximately independent of the event topology. The upper limits set extend over a considerably wider mass range than previous searches.
(ProQuest: ... denotes formulae and/or non-USASCII text omitted; see image) A search is presented for a high-mass Higgs boson in the ..., ..., ..., and ... decay modes using the ATLAS detector at the ...CERN Large Hadron Collider. The search uses proton-proton collision data at a centre-of-mass energy of 8 TeV corresponding to an integrated luminosity of 20.3 fb... The results of the search are interpreted in the scenario of a heavy Higgs boson with a width that is small compared with the experimental mass resolution. The Higgs boson mass range considered extends up to ... for all four decay modes and down to as low as 140 ..., depending on the decay mode. No significant excess of events over the Standard Model prediction is found. A simultaneous fit to the four decay modes yields upper limits on the production cross-section of a heavy Higgs boson times the branching ratio to ... boson pairs. 95 % confidence level upper limits range from 0.53 pb at ... GeV to 0.008 pb at ... GeV for the gluon-fusion production mode and from 0.31 pb at ... GeV to 0.009 pb at ... GeV for the vector-boson-fusion production mode. The results are also interpreted in the context of Type-I and Type-II two-Higgs-doublet models.
Studies of the spin, parity and tensor couplings of the Higgs boson in the
H
→
Z
Z
∗
→
4
ℓ
,
H
→
W
W
∗
→
e
ν
μ
ν
and
H
→
γ
γ
decay processes at the LHC are presented. The investigations are based on
...25
fb
-
1
of
pp
collision data collected by the ATLAS experiment at
s
=
7
TeV and
s
=
8
TeV. The Standard Model (SM) Higgs boson hypothesis, corresponding to the quantum numbers
J
P
=
0
+
, is tested against several alternative spin scenarios, including non-SM spin-0 and spin-2 models with universal and non-universal couplings to fermions and vector bosons. All tested alternative models are excluded in favour of the SM Higgs boson hypothesis at more than 99.9 % confidence level. Using the
H
→
Z
Z
∗
→
4
ℓ
and
H
→
W
W
∗
→
e
ν
μ
ν
decays, the tensor structure of the interaction between the spin-0 boson and the SM vector bosons is also investigated. The observed distributions of variables sensitive to the non-SM tensor couplings are compatible with the SM predictions and constraints on the non-SM couplings are derived.
(ProQuest: ... denotes formulae and/or non-USASCII text omitted; see image) The luminosity calibration for the ATLAS detector at the LHC during pp collisions at ... in 2010 and 2011 is presented. ...Evaluation of the luminosity scale is performed using several luminosity-sensitive detectors, and comparisons are made of the long-term stability and accuracy of this calibration applied to the pp collisions at ... A luminosity uncertainty of ... is obtained for the 47 pb^sup -1^ of data delivered to ATLAS in 2010, and an uncertainty of ... is obtained for the 5.5 fb^sup -1^ delivered in 2011.
A
bstract
Results of a search for
H
→
ττ
decays are presented, based on the full set of proton-proton collision data recorded by the ATLAS experiment at the LHC during 2011 and 2012. The data ...correspond to integrated luminosities of 4.5 fb
−1
and 20.3 fb
−1
at centre-of-mass energies of
s
=
7
TeV and
s
=
8
TeV respectively. All combinations of leptonic (
τ
→
ℓ
ν
ν
¯
with
ℓ
=
e, μ
) and hadronic (
τ
→ hadrons
ν
) tau decays are considered. An excess of events over the expected background from other Standard Model processes is found with an observed (expected) significance of 4.5 (3.4) standard deviations. This excess provides evidence for the direct coupling of the recently discovered Higgs boson to fermions. The measured signal strength, normalised to the Standard Model expectation, of
μ
= 1. 43
− 0.37
+ 0.43
is consistent with the predicted Yukawa coupling strength in the Standard Model.
This paper presents the performance of the ATLAS muon reconstruction during the LHC run with
p
p
collisions at
s
=
7
–8 TeV in 2011–2012, focusing mainly on data collected in 2012. Measurements of ...the reconstruction efficiency and of the momentum scale and resolution, based on large reference samples of
J
/
ψ
→
μ
μ
,
Z
→
μ
μ
and
Υ
→
μ
μ
decays, are presented and compared to Monte Carlo simulations. Corrections to the simulation, to be used in physics analysis, are provided. Over most of the covered phase space (muon
|
η
|
<
2.7
and
5
≲
p
T
≲
100
GeV) the efficiency is above
99
%
and is measured with per-mille precision. The momentum resolution ranges from
1.7
%
at central rapidity and for transverse momentum
p
T
≃
10
GeV, to
4
%
at large rapidity and
p
T
≃
100
GeV. The momentum scale is known with an uncertainty of
0.05
%
to
0.2
%
depending on rapidity. A method for the recovery of final state radiation from the muons is also presented.
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