pinecone/core-2020-05-10-deduplication huggingface dataset:
Excited electronic states from a variational approach based on
  symmetry-projected Hartree--Fock configurations

Recent work from our research group has demonstrated that symmetry-projected
Hartree--Fock (HF) methods provide a compact representation of molecular ground
state wavefunctions based on a superposition of non-orthogonal Slater
determinants. The symmetry-projected ansatz can account for static correlations
in a computationally efficient way. Here we present a variational extension of
this methodology applicable to excited states of the same symmetry as the
ground state. Benchmark calculations on the C$_2$ dimer with a modest basis
set, which allows comparison with full configuration interaction results,
indicate that this extension provides a high quality description of the
low-lying spectrum for the entire dissociation profile. We apply the same
methodology to obtain the full low-lying vertical excitation spectrum of
formaldehyde, in good agreement with available theoretical and experimental
data, as well as to a challenging model $C_{2v}$ insertion pathway for BeH$_2$.
The variational excited state methodology developed in this work has two
remarkable traits: it is fully black-box and will be applicable to fairly large
systems thanks to its mean-field computational cost
ARRAKIS: Atlas of Resonance Rings As Known In the S4G

Resonance rings are the consequence of secular evolution processes that
redistribute material and angular momentum in discs. We produced a Catalogue
and an Atlas of the rings detected in the Spitzer Survey of Stellar Structure
in Galaxies (S4G) and to conduct a statistical study of the data in the
Catalogue.
  We traced the contours of rings previously identified by Buta et al. (in
preparation) and fitted them with ellipses. We found the orientation of bars by
studying the galaxy ellipse fits from S4G's Pipeline 4. We used the galaxy
orientation data obtained by S4G's Pipeline 4 to obtain intrinsic ellipticities
and orientations of rings and the bars.
  ARRAKIS contains data on 724 ringed galaxies in the S4G. The frequency of
resonance rings in the S4G is of 16+-1% and 35+-1% for outer and inner
features, respectively. Outer rings are mostly found in Hubble stages -1<=T<=4.
Inner rings are found in a distribution that covers the range -1<=T<=7. We
confirm that outer rings have two preferred orientations, parallel and
perpendicular to the bar. We confirm a tendency for inner rings to be oriented
parallel to the bar, but we find that a significant fraction (~50%) of them
have random orientations with respect to the bar. These misaligned inner rings
are mostly found in late-type galaxies (T>=4). This may be due to spiral modes
decoupled from the bar dominating the Fourier amplitude spectrum at the radius
of the inner ring.
  We find that the fraction of barred galaxies hosting outer (inner) rings is
~1.7 times (~1.3 times) that in unbarred galaxies. The fact that rings are only
mildly favoured by bars suggests that those in unbarred galaxies either formed
due to weak departures from the axisymmetry of the galactic potential or that
they are born because of bars that have been destroyed after the ring
formation.Comment: Accepted for publication in A&A. Some figures have a degraded
  resolution and the appendix with images of all the galaxies in ARRAKIS has
  been omitted. A version of the paper with the full resolution images and with
  the omitted appendix can be found at
  http://cc.oulu.fi/~scomeron/arrakis_v12_printer.pd
Equivariant Alexandrov geometry and orbifold finiteness

Let a compact Lie group act isometrically on a non-collapsing sequence of
compact Alexandrov spaces with fixed dimension and uniform lower curvature and
upper diameter bounds. If the sequence of actions is equicontinuous and
converges in the equivariant Gromov--Hausdorff topology, then the limit space
is equivariantly homeomorphic to spaces in the tail of the sequence.
  As a consequence, the class of Riemannian orbifolds of dimension $n$ defined
by a lower bound on the sectional curvature and the volume and an upper bound
on the diameter has only finitely many members up to orbifold homeomorphism.
Furthermore, any class of isospectral Riemannian orbifolds with a lower bound
on the sectional curvature is finite up to orbifold homeomorphism.Comment: 25 pages, in v2 citation for Theorem 2.13 was corrected, in this
  version the material of arXiv:1401.0739 was incorporated. The combined
  article has been published in the Journal of Geometric Analysi
CO excitation of normal star forming galaxies out to z=1.5 as regulated
  by the properties of their interstellar medium

We investigate the CO excitation of normal star forming disk galaxies at
z=1.5 using IRAM PdBI observations of the CO[2-1], CO[3-2] and CO[5-4]
transitions for 4 galaxies, including VLA observations of CO[1-0] for 3 of
them, with the aim of constraining the average state of H2 gas. Exploiting
prior knowledge of the velocity range, spatial extent and size of the CO
emission we measure reliable line fluxes with S/N>4-7 for individual
transitions. While the average CO Spectral Line Energy Distribution (SLED) has
a sub-thermal excitation similar to the Milky Way (MW) up to CO[3-2], we show
that the average CO[5-4] emission is four times stronger than assuming MW
excitation. This demonstrates the presence of an additional component of more
excited, denser and possibly warmer molecular gas. The ratio of CO[5-4] to
lower-J CO emission is lower than in local (U)LIRGs and high-redshift SMGs,
correlating closely with the average intensity of the radiation field <U> and
with the star formation surface density, but not with the SF efficiency (SFE).
The CO[5-4] luminosity correlates linearly with LIR over 4 orders of
magnitudes, with z=1.5 BzK galaxies following the same trend as local spirals
and (U)LIRGs and high redshift star bursting SMGs. The CO[5-4] luminosity is
thus empirically related to the dense gas, and might be a more convenient way
to probe it than standard high--density tracers that are much fainter than CO.
We see excitation variations among our sample galaxies, that can be linked to
their evolutionary state and clumpiness in optical rest frame images. In one
galaxy we see spatially resolved excitation variations, where the more highly
excited part of the galaxy corresponds to the location of massive SF clumps.
This supports to models that suggest that giant clumps are the main source of
the high excitation CO emission in high redshift disk-like galaxies.Comment: Accepted for publication in A&
Flat connections from flat gerbes

We discuss some aspects of heterotic-Type I duality. We focus on toroidal
compactification, with special attention for the topology of the gauge group,
and the topology of the bundle. We review the arguments leading to a
classification of Spin(32)/Z_2-bundles over tori, suitable for string
compactifications. A central role is played by n-gerbes with connection, a
generalization of bundles with connection.Comment: LaTex, 6 pages, contributed to the proceedings of the RTN meeting
  ``The Quantum Structure of Spacetime and the Geometric Nature of Fundamental
  Interactions'', (Corfu, September 2001
Covariant meson-baryon scattering with chiral and large $N_{c}$ constraints

We give a review of recent progress on the application of the relativistic chiral SU(3) Lagrangian to meson-baryon scattering. It is shown that a combined chiral and 1/N_c expansion of the Bethe-Salpeter interaction kernel leads to a good description of the kaon-nucleon, antikaon-nucleon and pion-nucleon scattering data typically up to laboratory momenta of p_lab about 500 MeV. We solve the covariant coupled channel Bethe-Salpeter equation with the interaction kernel truncated to chiral order Q^3 where we include only those terms which are leading in the large N_c limit of QCD
Fusion products of Kirillov-Reshetikhin modules and fermionic
  multiplicity formulas

We give a complete description of the graded multiplicity space which appears
in the Feigin-Loktev fusion product [FL99] of graded Kirillov-Reshetikhin
modules for all simple Lie algebras. This construction is used to obtain an
upper bound formula for the fusion coefficients in these cases. The formula
generalizes the case of g=A_r [AKS06], where the multiplicities are generalized
Kostka polynomials [SW99,KS02]. In the case of other Lie algebras, the formula
is the the fermionic side of the X=M conjecture [HKO+99]. In the cases where
the Kirillov-Reshetikhin conjecture, regarding the decomposition formula for
tensor products of KR-modules, has been been proven in its original, restricted
form, our result provides a proof of the conjectures of Feigin and Loktev
regarding the fusion product multiplicites.Comment: 22 pages; v2: minor changes; v3: exposition clarifie
Two-Proton Correlations near Midrapidity in p+Pb and S+Pb Collisions at
  the CERN SPS

Correlations of two protons emitted near midrapidity in p+Pb collisions at
450 GeV/c and S+Pb collisions at 200A GeV/c are presented, as measured by the
NA44 Experiment. The correlation effect, which arises as a result of final
state interactions and Fermi-Dirac statistics, is related to the space-time
characteristics of proton emission. The measured source sizes are smaller than
the size of the target lead nucleus but larger than the sizes of the
projectiles. A dependence on the collision centrality is observed; the source
size increases with decreasing impact parameter. Proton source sizes near
midrapidity appear to be smaller than those of pions in the same interactions.
Quantitative agreement with the results of RQMD (v1.08) simulations is found
for p+Pb collisions. For S+Pb collisions the measured correlation effect is
somewhat weaker than that predicted by the model simulations, implying either a
larger source size or larger contribution of protons from long-lived particle
decays.Comment: 10 pages (LaTeX) text, 4 (EPS) figures; accepted for publication in
  Phys. Lett.
Statistics of 2+ Levels in Even-Even Nuclei

Using all the available empirical information, we analyze the spacing
distributions of low-lying 2-plus levels of even-even nuclei. To obtain
statistically relevant samples, the nuclei are grouped into classes defined by
the ratio R4/2 of the excitation energies of the first 4-plus and 2-plus
levels. This ratio serves as a measure of collectivity in nuclei. With the help
of Bayesian inference, we determine the chaoticity parameter for each class.
This parameter is found to vary strongly with R4/2 and takes particularly small
values in nuclei that have one of the dynamical symmetries of the interacting
Boson model.Comment: 11 pages, 2 figures; v2: added references; layout improve
Field equations in teleparallel spacetime: Einstein's Fernparallelismus
  approach towards unified field theory

A historical account of Einstein's 'Fernparallelismus' approach towards a
unified field theory of gravitation and electromagnetism is given. In this
theory, a space-time characterized by a curvature-free connection in
conjunction with a metric tensor field, both defined in terms of a dynamical
tetrad field, is investigated. The approach was pursued by Einstein in a number
of publications that appeared in the period from summer 1928 until spring 1931.
In the historical analysis special attention is given to the question of how
Einstein tried to find field equations for the tetrads. We claim that it was
the failure to find and justify a uniquely determined set of acceptable field
equations which eventually led to Einstein's abandoning of this approach. We
comment on some historical and systematic similarities between the
'Fernparallelismus' episode and the 'Entwurf' theory, i.e. the precursor theory
of general relativity pursued by Einstein in the years 1912-1915.Comment: 47 page
Dispersive calculation of complex Regge trajectories for the lightest
  $f_2$ resonances

We apply a recently developed dispersive formalism to calculate the Regge
trajectories of the $f_2(1270)$ and $f_2'(1525)$ mesons. Trajectories are
calculated, not fitted to a family of resonances. Assuming that these spin-2
resonances can be treated in the elastic approximation the only input are the
pole position and residue of the resonances. In both cases, the predicted Regge
trajectories are almost real and linear, with slopes in agreement with the
universal value of order 1 GeV$^{-2}$.Comment: 8 pages, 4 figure
Search for heavy Majorana neutrinos with the ATLAS detector in pp
  collisions at $\sqrt{s} = 8$ TeV

A search for heavy Majorana neutrinos in events containing a pair of
high-$p_{\mathrm{T}}$ leptons of the same charge and high-$p_{\mathrm{T}}$ jets
is presented. The search uses $20.3 \mathrm{fb}^{-1}$ of $pp$ collision data
collected with the ATLAS detector at the CERN Large Hadron Collider with a
centre-of-mass energy of $\sqrt{s} = 8$ TeV. The data are found to be
consistent with the background-only hypothesis based on the Standard Model
expectation. In the context of a Type-I seesaw mechanism, limits are set on the
production cross-section times branching ratio for production of heavy Majorana
neutrinos in the mass range between 100 and 500 GeV. The limits are
subsequently interpreted as limits on the mixing between the heavy Majorana
neutrinos and the Standard Model neutrinos. In the context of a left-right
symmetric model, limits on the production cross-section times branching ratio
are set with respect to the masses of heavy Majorana neutrinos and heavy gauge
bosons $W_{\mathrm{R}}$ and $Z'$.Comment: 28 pages plus author list (44 pages total), 11 figures, 6 tables,
  submitted to JHEP, all figures including auxiliary figures are available at
  http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/EXOT-2012-24
Disrupted Globular Clusters Can Explain the Galactic Center Gamma Ray
  Excess

The Fermi satellite has recently detected gamma ray emission from the central
regions of our Galaxy. This may be evidence for dark matter particles, a major
component of the standard cosmological model, annihilating to produce
high-energy photons. We show that the observed signal may instead be generated
by millisecond pulsars that formed in dense star clusters in the Galactic halo.
Most of these clusters were ultimately disrupted by evaporation and
gravitational tides, contributing to a spherical bulge of stars and stellar
remnants. The gamma ray amplitude, angular distribution, and spectral
signatures of this source may be predicted without free parameters, and are in
remarkable agreement with the observations. These gamma rays are from fossil
remains of dispersed clusters, telling the history of the Galactic bulge.Comment: ApJ accepted, replaced with accepted version. Text reorganized,
  results and conclusions unchange
Hanbury-Brown-Twiss measurements at large rapidity separations, or can
  we measure the proton radius in p-A collisions?

We point out that current calculations of inclusive two-particle correlations
in p-A collisions based on the Color Glass Condensate approach exhibit a
contribution from Hanbury-Brown-Twiss correlations. These HBT correlations are
quite distinct from the standard ones, in that they are apparent for particles
widely separated in rapidity. The transverse size of the emitter which is
reflected in these correlations is the gluonic size of the proton. This raises
an interesting possibility of measuring the proton size directly by the HBT
effect of particle pairs produced in p-A collisions.Comment: 11 pages, 3 eps figures; v2: comments, discussions, references and
  acknowledgements added, conclusions unchanged, final versio
Combinatorial representations

23pp. Submitted to J. Combinatorial Theory (Series A)arXiv:1109.1216v1 [math.CO]23pp. Submitted to J. Combinatorial Theory (Series A)23pp. Submitted to J. Combinatorial Theory (Series A)This paper introduces combinatorial representations, which generalise the notion of linear representations of matroids. We show that any family of subsets of the same cardinality has a combinatorial representation via matrices. We then prove that any graph is representable over all alphabets of size larger than some number depending on the graph. We also provide a characterisation of families representable over a given alphabet. Then, we associate a rank function and a rank operator to any representation which help us determine some criteria for the functions used in a representation. While linearly representable matroids can be viewed as having representations via matrices with only one row, we conclude this paper by an investigation of representations via matrices with only two rows
Mitochondrial rhomboid PARL regulates cytochrome c release during apoptosis via OPA1-dependent cristae remodeling

Rhomboids, evolutionarily conserved integral membrane proteases, participate in crucial signaling pathways. Presenilin-associated rhomboid-like (PARL) is an inner mitochondrial membrane rhomboid of unknown function, whose yeast ortholog is involved in mitochondrial fusion. Parl-/- mice display normal intrauterine development but from the fourth postnatal week undergo progressive multisystemic atrophy leading to cachectic death. Atrophy is sustained by increased apoptosis, both in and ex vivo. Parl-/- cells display normal mitochondrial morphology and function but are no longer protected against intrinsic apoptotic death stimuli by the dynamin-related mitochondrial protein OPA1. Parl-/- mitochondria display reduced levels of a soluble, intermembrane space (IMS) form of OPA1, and OPA1 specifically targeted to IMS complements Parl-/- cells, substantiating the importance of PARL in OPA1 processing. Parl-/- mitochondria undergo faster apoptotic cristae remodeling and cytochrome c release. These findings implicate regulated intramembrane proteolysis in controlling apoptosis.status: publishe
If-then planning helps school-aged children to ignore attractive distractions

Can children improve shielding an ongoing task from distractions by if-then planning (i.e., by forming implementation intentions)? In an experimental study, the situational and personal limits of action control by distraction-inhibiting implementation intentions
(“If a distraction comes up, then I will ignore it!”) were tested by comparing them to simple goal intentions (“I will ignore distractions!”).Goal intentions were sufficient to successfully ignore distractions of low attractiveness. In the presence of moderately and highly attractive distractions, as well as a distraction presented out of the children’s sight, however, only implementation intentions improved children’s task shielding, as indicated by faster response times in an ongoing categorization task and shorter periods of looking at highly attractive distractions presented out of their field of vision. These findings held true regardless of the children’s temperament and language competency. Implications for research on planning and developmental research on self-control are discussed.status: publishe
Photoproduction of π + π − pairs in a model with tensor-pomeron and vector-odderon exchange

We consider the reaction γp → π + π − p at high energies. Our description includes dipion production via the resonances ρ , ω , ρ ′ and f 2 , and via non-resonant mechanisms. The calculation is based on a model of high energy scattering with the exchanges of photon, pomeron, odderon and reggeons. The pomeron and the C = +1 reggeons are described as effective tensor exchanges, the odderon and the C = −1 reggeons as effective vector exchanges. We obtain a gauge-invariant version of the Drell-Söding mechanism which produces the skewing of the ρ-meson shape. Starting from the explicit formulae for the matrix element for dipion production we construct an event generator which comprises all contributions mentioned above and includes all interference terms. We give examples of total and differential cross sections and discuss asymmetries which are due to interference of C = +1 and C = −1 exchange contributions. These asymmetries can be used to search for odderon effects. Our model is intended to provide all necessary theoretical tools for a detailed experimental analysis of elastic dipion production for which data exist from fixed target experiments, from HERA, and are now being collected by LHC experiments
Tri/Bi-maximal lepton mixing and leptogenesis

In models with flavour symmetries added to the gauge group of the Standard Model the CP-violating asymmetry necessary for leptogenesis may be related with low-energy parameters. A particular case of interest is when the flavour symmetry produces exact Tri/Bi-maximal lepton mixing leading to a vanishing CP-violating asymmetry. In this paper we present a model-independent discussion that confirms this always occurs for unflavoured leptogenesis in type I see-saw scenarios, noting however that Tri/Bi-maximal mixing does not imply a vanishing asymmetry in general scenarios where there is interplay between type I and other see-saws. We also consider a specific model where the exact Tri/Bi-maximal mixing is lifted by corrections that can be parametrised by a small number of degrees of freedom and analyse in detail the existing link between low and high-energy parameters - focusing on how the deviations from Tri/Bi-maximal are connected to the parameters governing leptogenesis.We thank Yin Lin and Enrico Nardi for useful discussions. The work of FB has been\ud
partially supported by European Commission Contracts MRTN-CT-2004-503369 and IL-\ud
IAS/N6 RII3-CT-2004-506222 and by the foundation for Fundamental Research of Matter\ud
(FOM) and the National Organization for Scienti c Research (NWO). The work of IdMV\ud
was supported by FCT under the grant SFRH/BPD/35919/2007. The work of IdMV was\ud
partially supported by FCT through the projects POCI/81919/2007, CERN/FP/83503/2008\ud
and CFTP-FCT UNIT 777 which are partially funded through POCTI (FEDER) and by\ud
the Marie Curie RTN MRTN-CT-2006-035505. LM recognises that this work has been\ud
partly supported by the European Commission under contract MRTN-CT-2004-503369\ud
and MRTN-CT-2006-035505. The work of SM supported by MEC-Valencia MEC grant\ud
FPA2008-00319/FPA, by European Commission Contracts MRTN-CT-2004-503369 and\ud
ILIAS/N6 RII3-CT-2004-506222