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Measurements of the Higgs boson inclusive and differential fiducial cross-sections in the diphoton decay channel with pp collisions at √s=13 TeV with the ATLAS detector
A measurement of inclusive and differential fiducial cross-sections for the production of the Higgs boson decaying into two photons is performed using 139 fb−1 of proton-proton collision data recorded at = 13 TeV by the ATLAS experiment at the Large Hadron Collider. The inclusive cross-section times branching ratio, in a fiducial region closely matching the experimental selection, is measured to be 67 ± 6 fb, which is in agreement with the state-of-the-art Standard Model prediction of 64 ± 4 fb. Extrapolating this result to the full phase space and correcting for the branching ratio, the total cross-section for Higgs boson production is estimated to be 58 ± 6 pb. In addition, the cross-sections in four fiducial regions sensitive to various Higgs boson production modes and differential cross-sections as a function of either one or two of several observables are measured. All the measurements are found to be in agreement with the Standard Model predictions. The measured transverse momentum distribution of the Higgs boson is used as an indirect probe of the Yukawa coupling of the Higgs boson to the bottom and charm quarks. In addition, five differential cross-section measurements are used to constrain anomalous Higgs boson couplings to vector bosons in the Standard Model effective field theory framework.</p
Testing Linear-Invariant Non-Linear Properties
We consider the task of testing properties of Boolean functions that are
invariant under linear transformations of the Boolean cube. Previous work in
property testing, including the linearity test and the test for Reed-Muller
codes, has mostly focused on such tasks for linear properties. The one
exception is a test due to Green for "triangle freeness": a function
f:\cube^{n}\to\cube satisfies this property if do not all
equal 1, for any pair x,y\in\cube^{n}.
Here we extend this test to a more systematic study of testing for
linear-invariant non-linear properties. We consider properties that are
described by a single forbidden pattern (and its linear transformations), i.e.,
a property is given by points v_{1},...,v_{k}\in\cube^{k} and
f:\cube^{n}\to\cube satisfies the property that if for all linear maps
L:\cube^{k}\to\cube^{n} it is the case that do
not all equal 1. We show that this property is testable if the underlying
matroid specified by is a graphic matroid. This extends
Green's result to an infinite class of new properties.
Our techniques extend those of Green and in particular we establish a link
between the notion of "1-complexity linear systems" of Green and Tao, and
graphic matroids, to derive the results.Comment: This is the full version; conference version appeared in the
proceedings of STACS 200
Formation of antideuterons in heavy ion collisions
The antideuteron production rate at high-energy heavy ions collisions is
calculated basing on the concept of anti-d formation by antinucleons which move
in the mean field of the fireball constituents (mainly pions). The explicit
formula is presented for the coalescence parameter B_2 in terms of deuteron
binding energy and fireball volume.Comment: 7 pages, 1 figure, latex. v3: argumentation improved, references
adde
Production Mechanism for Quark Gluon Plasma in Heavy Ion Collisions
A general scheme is proposed here to describe the production of semi soft and
soft quarks and gluons that form the bulk of the plasma in ultra relativistic
heavy ion collisions. We show how to obtain rates as a function of time in a
self consistent manner, without any ad-hoc assumption. All the required
features - the dynamical nature of QCD vacuum, the non-Markovian nature of the
production, and quasi particle nature of the partons, and the importance of
quantum interference effects are naturally incorporated. We illustrate the
results with a realistic albeit toy model and show how almost all the currently
employed source terms are unreliable in their predictions. We show the rates in
the momentum space and indicate at the end how to extract the full phase-space
dependence.Comment: 4 pages, 4 figures, two colum
Continuous melting of compact polymers
The competition between chain entropy and bending rigidity in compact
polymers can be addressed within a lattice model introduced by P.J. Flory in
1956. It exhibits a transition between an entropy dominated disordered phase
and an energetically favored crystalline phase. The nature of this
order-disorder transition has been debated ever since the introduction of the
model. Here we present exact results for the Flory model in two dimensions
relevant for polymers on surfaces, such as DNA adsorbed on a lipid bilayer. We
predict a continuous melting transition, and compute exact values of critical
exponents at the transition point.Comment: 5 pages, 1 figur
An Exactly Solvable Anisotropic Directed Percolation Model in Three Dimensions
We solve exactly a special case of the anisotropic directed bond percolation
problem in three dimensions, in which the occupation probability is 1 along two
spatial directions, by mapping it to a five-vertex model. We determine the
asymptotic shape of the ininite cluster and hence the direction dependent
critical probability. The exponents characterising the fluctuations of the
boundary of the wetted cluster in d-dimensions are related to those of the
(d-2)-dimensional KPZ equation.Comment: 4 pages, RevTex, 4 figures. 1 reference added, minor change
Theory of tricriticality for miscut surfaces
We propose a theory for the observed tricriticality in the orientational
phase diagram of Si(113) misoriented towards [001]. The systems seems to be at
or close to a very special point for long range interactions.Comment: Revtex, 1 ps figur
Ground State Entropy of Potts Antiferromagnets: Bounds, Series, and Monte Carlo Measurements
We report several results concerning , the
exponent of the ground state entropy of the Potts antiferromagnet on a lattice
. First, we improve our previous rigorous lower bound on for
the honeycomb (hc) lattice and find that it is extremely accurate; it agrees to
the first eleven terms with the large- series for . Second, we
investigate the heteropolygonal Archimedean lattice, derive a
rigorous lower bound, on , and calculate the large- series
for this function to where . Remarkably, these agree
exactly to all thirteen terms calculated. We also report Monte Carlo
measurements, and find that these are very close to our lower bound and series.
Third, we study the effect of non-nearest-neighbor couplings, focusing on the
square lattice with next-nearest-neighbor bonds.Comment: 13 pages, Latex, to appear in Phys. Rev.
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