pinecone/core-2020-05-10-deduplication huggingface dataset:
Gr\"obner bases of syzygies and Stanley depth

Let F. be a any free resolution of a Z^n-graded submodule of a free module
over the polynomial ring K[x_1, ..., x_n]. We show that for a suitable term
order on F., the initial module of the p'th syzygy module Z_p is generated by
terms m_ie_i where the m_i are monomials in K[x_{p+1}, ..., x_n]. Also for a
large class of free resolutions F., encompassing Eliahou-Kervaire resolutions,
we show that a Gr\"obner basis for Z_p is given by the boundaries of generators
of F_p. We apply the above to give lower bounds for the Stanley depth of the
syzygy modules Z_p, in particular showing it is at least p+1. We also show that
if I is any squarefree ideal in K[x_1, ..., x_n], the Stanley depth of I is at
least of order the square root of 2n.Comment: 13 page
Line-driven disk wind models with an improved line force

We describe an efficient method of calculating the radiation pressure due to
spectral lines, including all the terms in the velocity gradient tensor. We
apply this method to calculate the two-dimensional, time-dependent structure of
winds from luminous disks. Qualitative features of our new models are very
similar to those we calculated including only the dominant terms in the tensor
(Proga, Stone & Drew 1998, hereafter PSD). In particular, we find that models
which displayed unsteady behaviour in PSD are also unsteady with the new
method, and gross properties of the winds, such as mass-loss rate and
characteristic velocity are not changed by the more accurate approach. The
largest change caused by the new method is in the disk-wind opening angle:
winds driven only by the disk radiation are more polar with the new method
while winds driven by the disk and central object radiation are typically more
equatorial. In the closing discussion, we provide further insight into the way
the geometry of the radiation field and consequent flow determines the time
properties of the flow.Comment: LaTeX, 9 pages, including three tables, 10 postscript files, requires
  mn.sty, to appear in MNRA
Two-loop QCD corrections to massless identical quark scattering

We present the two-loop virtual QCD corrections to the scattering of massless
identical quarks, q qbar to q qbar, in conventional dimensional regularisation
and using the MSbar scheme. The structure of the infrared divergences agrees
with that predicted by Catani while expressions for the finite remainder are
given for the q qbar to qbar q and the q q to q q (qbar qbar to qbar qbar)
scattering processes in terms of polylogarithms. The results presented here
form a vital part of the next-to-next-to-leading order contribution to
inclusive jet production in hadron colliders and will play a crucial role in
improving the theoretical prediction for jet cross sections in hadron-hadron
collisions.Comment: 20 pages, journal version, title changed, latex with JHEP.cl
Higgsino and Wino Dark Matter from Q-ball Decay in Affleck-Dine
  Baryogenesis

We claim that the Higgsino-like and wino-like neutralinos can be good dark
matter candidates if they are produced by the late time decay of Q-ball, which
is generally formed in Affleck-Dine baryogenesis. The late time decays of the
Q-balls into these LSP's and subsequent pair annihilations of the LSP's
naturally lead to the desired mass density of dark matter. Furthermore, these
dark matter can be much more easily detected by the dark-matter search
experiments than the standard bino-like dark matter.Comment: 12 pages, LaTeX, 6 figures, version accepted for publication in PL
On the Colour Suppressed Decay Modes B^0 --> D_s^+ D_s^- and B_s^0 -->
  D^+ D^-

We point out that the decay modes B^0 --> D_s^+ D_s^- and B_s^0 --> D^+ D^-
have no factorized contribution. At quark level these dacays can only proceed
through the annihilation mechanism, which in the factorized limit give zero
amplitude due to current conservation. In this paper, we identify the
dominating non-factorizable (colour suppressed) contributions in terms of two
chiral loop contributions and one soft gluon emission contribution. The latter
contribution can be calculated in terms of the (lowest dimension) gluon
condensate within a recently developed heavy-light chiral quark model. We find
braching ratios BR(B^0 --> D_s^+ D_s^-) = 7*10^-5 and BR(B^0_s --> D^+ D^-) =
1*10^-3.Comment: 13 pages, 4 figure
Z' Mediated Flavor Changing Neutral Currents in B Meson Decays

We study the effects of an extra U(1)' gauge boson with flavor changing
couplings with fermion mass eigenstates on certain B meson decays that are
sensitive to such new physics contributions. In particular, we examine to what
extent the current data on B_d -> \phi K, B_d -> \eta' K and B_s -> \mu^+ \mu^-
decays may be explained in such models, concentrating on the example in which
the flavor changing couplings are left-chiral. We find that within reasonable
ranges of parameters, the Z' contribution can readily account for the anomaly
in S_{\phi K_S} but is not sufficient to explain large branching ratio of B_d
-> \eta' K with the same parameter value. S_{\phi K_S} and S_{\eta' K_S} are
seen to be the dominant observables that constrain the extra weak phase in the
model.Comment: 12 pages, 6 figures. Additional references added. Small modifications
  and corrections to Eq.(33) and (34) adde
Vector Mesons and Dence Skyrmion Matter

In our continuing effort to understand hadronic matter at high density, we
have developed a unified field theoretic formalism for dense skyrmion matter
using a single Lagrangian to describe simultaneously both matter and meson
fluctuations and studied in-medium properties of hadrons. Dropping the quartic
Skyrme term, we incorporate into our previous Lagrangian the vector mesons rho
and omega in a form which is consistent with the symmetries of QCD. The results
that we have obtained, reported here, expose a hitherto unsuspected puzzle
associated with the role the omega meson plays at short distance. Since the
omega meson couples to baryon density, it leads to a pseudo-gap scenario for
the chiral symmetry phase transition, which is at variance with standard
scenario of QCD at the phase transition. We find that in the presence of the
omega mesons, the scale-anomaly dilaton field is prevented from developing a
vanishing vacuum expectation value at the chiral restoration, as a consequence
of which the in-medium pion decay constant does not vanish. This seems to
indicate that the omega degree of freedom obstructs the vector manifestation
which is considered to be a generic feature of effective field theories matched
to QCD.Comment: 16 pages, 5 figures, references for Sec.5 adde
Combinatorial Hopf algebra structure on packed square matrices

We construct a new bigraded Hopf algebra whose bases are indexed by square
matrices with entries in the alphabet $\{0, 1, ..., k\}$, $k \geq 1$, without
null rows or columns. This Hopf algebra generalizes the one of permutations of
Malvenuto and Reutenauer, the one of $k$-colored permutations of Novelli and
Thibon, and the one of uniform block permutations of Aguiar and Orellana. We
study the algebraic structure of our Hopf algebra and show, by exhibiting
multiplicative bases, that it is free. We moreover show that it is self-dual
and admits a bidendriform bialgebra structure. Besides, as a Hopf subalgebra,
we obtain a new one indexed by alternating sign matrices. We study some of its
properties and algebraic quotients defined through alternating sign matrices
statistics.Comment: 35 page
Elliptic Fibrations with Rank Three Mordell-Weil Group: F-theory with
  U(1) x U(1) x U(1) Gauge Symmetry

We analyze general F-theory compactifications with U(1) x U(1) x U(1) Abelian
gauge symmetry by constructing the general elliptically fibered Calabi-Yau
manifolds with a rank three Mordell-Weil group of rational sections. The
general elliptic fiber is shown to be a complete intersection of two
non-generic quadrics in P^3 and resolved elliptic fibrations are obtained by
embedding the fiber as the generic Calabi-Yau complete intersection into Bl_3
P^3, the blow-up of P^3 at three points. For a fixed base B, there are finitely
many Calabi-Yau elliptic fibrations. Thus, F-theory compactifications on these
Calabi-Yau manifolds are shown to be labeled by integral points in reflexive
polytopes constructed from the nef-partition of Bl_3 P^3. We determine all 14
massless matter representations to six and four dimensions by an explicit study
of the codimension two singularities of the elliptic fibration. We obtain three
matter representations charged under all three U(1)-factors, most notably a
tri-fundamental representation. The existence of these representations, which
are not present in generic perturbative Type II compactifications, signifies an
intriguing universal structure of codimension two singularities of the elliptic
fibrations with higher rank Mordell-Weil groups. We also compute explicitly the
corresponding 14 multiplicities of massless hypermultiplets of a
six-dimensional F-theory compactification for a general base B.Comment: 48 pages, 1 figur
A neutron spectrometer for studying giant resonances with (p, n)
  reactions in inverse kinematics

A neutron spectrometer, the European Low-Energy Neutron Spectrometer (ELENS),
has been constructed to study exotic nuclei in inverse-kinematics experiments.
The spectrometer, which consists of plastic scintillator bars, can be operated
in the neutron energy range of 100 keV to 10 MeV. The neutron energy is
determined using the time-of-flight technique, while the position of the
neutron detection is deduced from the time-difference information from
photomultipliers attached to both ends of each bar. A novel wrapping method has
been developed for the plastic scintillators. The array has a larger than 25%
detection efficiency for neutrons of approximately 500 keV in kinetic energy
and an angular resolution of less than 1 degree. Details of the design,
construction and experimental tests of the spectrometer will be presented.Comment: 10 pages, 13 figure
Cogenesis in a universe with vanishing $B-L$ within a gauged $U(1)_x$
  extension

We consider a gauged $U(1)_x$ extension of the standard model and of the
minimal supersymmetric standard model where the dark matter fields are charged
under $U(1)_x$ and carry lepton number while the standard model fields and
fields of the minimal supersymmetric standard model are neutral under $U(1)_x$.
We consider leptogenesis in this class of models with all fundamental
interactions having no violation of lepton number, and the total $B-L$ in the
universe vanishes. Such leptogenesis leads to equal and opposite lepton numbers
in the visible sector and in the dark sector, and thus also produces asymmetric
dark matter. Part of the lepton numbers generated in the leptonic sector
subsequently transfer to the baryonic sector via sphaleron interactions. The
stability of the dark particles is protected by the $U(1)_x$ gauge symmetry. A
kinetic mixing between the $U(1)_x$ and the $U(1)_Y$ gauge bosons allows for
dissipation of the symmetric component of dark matter. The case when $U(1)_x$
is $U(1)_{B-L}$ is also discussed for the supersymmetric case. This case is
particularly interesting in that we have a gauged $U(1)_{B-L}$ which ensures
the conservation of $B-L$ with an initial condition of a vanishing $B-L$ in the
universe. Phenomenological implications of the proposed extensions are
discussed, which include implications for electroweak physics, neutrino masses
and mixings, and lepton flavor changing processes such as $\ell_i \to \ell_j
\gamma$. We also briefly discuss the direct detection of the dark matter in the
model.Comment: 9 pages, 3 figure
The superconformal index and an elliptic algebra of surface defects

In this paper we continue the study of the superconformal index of
four-dimensional $\mathcal{N}=2$ theories of class $\mathcal{S}$ in the
presence of surface defects. Our main result is the construction of an algebra
of difference operators, whose elements are labeled by irreducible
representations of $A_{N-1}$. For the fully antisymmetric tensor
representations these difference operators are the Hamiltonians of the elliptic
Ruijsenaars-Schneider system. The structure constants of the algebra are
elliptic generalizations of the Littlewood-Richardson coefficients. In the
Macdonald limit, we identify the difference operators with local operators in
the two-dimensional TQFT interpretation of the superconformal index. We also
study the dimensional reduction to difference operators acting on the
three-sphere partition function, where they characterize supersymmetric defects
supported on a circle, and show that they are transformed to supersymmetric
Wilson loops under mirror symmetry. Finally, we compare to the difference
operators that create 't Hooft loops in the four-dimensional $\mathcal{N}=2^*$
theory on a four-sphere by embedding the three-dimensional theory as an
S-duality domain wall.Comment: 53+16 pages, 12 figures; v2: minor corrections, references added;
  published versio
CSI 2264: Simultaneous optical and infrared light curves of young
  disk-bearing stars in NGC 2264 with CoRoT and Spitzer-- evidence for multiple
  origins of variability

We present the Coordinated Synoptic Investigation of NGC 2264, a continuous
30-day multi-wavelength photometric monitoring campaign on more than 1000 young
cluster members using 16 telescopes. The unprecedented combination of
multi-wavelength, high-precision, high-cadence, and long-duration data opens a
new window into the time domain behavior of young stellar objects. Here we
provide an overview of the observations, focusing on results from Spitzer and
CoRoT. The highlight of this work is detailed analysis of 162 classical T Tauri
stars for which we can probe optical and mid-infrared flux variations to 1%
amplitudes and sub-hour timescales. We present a morphological variability
census and then use metrics of periodicity, stochasticity, and symmetry to
statistically separate the light curves into seven distinct classes, which we
suggest represent different physical processes and geometric effects. We
provide distributions of the characteristic timescales and amplitudes, and
assess the fractional representation within each class. The largest category
(>20%) are optical "dippers" having discrete fading events lasting ~1-5 days.
The degree of correlation between the optical and infrared light curves is
positive but weak; notably, the independently assigned optical and infrared
morphology classes tend to be different for the same object. Assessment of flux
variation behavior with respect to (circum)stellar properties reveals
correlations of variability parameters with H$\alpha$ emission and with
effective temperature. Overall, our results point to multiple origins of young
star variability, including circumstellar obscuration events, hot spots on the
star and/or disk, accretion bursts, and rapid structural changes in the inner
disk.Comment: Published in AJ. 59 pages; 4 tables; 49 figures, most of which are
  highly degraded to fit size limits. Author name typo corrected. For a better
  resolution version, please visit
  http://web.ipac.caltech.edu/staff/amc/codyetal2014.pd
The windows for kinetically mixed Z'-mediated dark matter and the
  galactic center gamma ray excess

One of the simplest hidden sectors with signatures in the visible sector is
fermionic dark matter $\chi$ coupled to a $Z'$ gauge boson that has purely
kinetic mixing with the standard model hypercharge. We consider the combined
constraints from relic density, direct detection and collider experiments on
such models in which the dark matter is either a Dirac or a Majorana fermion.
We point out sensitivity to details of the UV completion for the Majorana
model. For kinetic mixing parameter $\epsilon \le 0.01$, only relic density and
direct detection are relevant, while for larger $\epsilon$, electroweak
precision, LHC dilepton, and missing energy constraints become important. We
identify regions of the parameter space of $m_\chi$, $m_{Z'}$, dark gauge
coupling and $\epsilon$ that are most promising for discovery through these
experimental probes. We study the compatibility of the models with the galactic
center gamma ray excess, finding agreement at the 2-3$\sigma$ level for the
Dirac model.Comment: 13 pages, 10 figures; v.2 added reference; v.3 minor clarifications,
  published versio
Covariant Residual Entropy

A recently explored interesting quantity in AdS/CFT, dubbed 'residual
entropy', characterizes the amount of collective ignorance associated with
either boundary observers restricted to finite time duration, or bulk observers
who lack access to a certain spacetime region. However, the previously-proposed
expression for this quantity involving variation of boundary entanglement
entropy (subsequently renamed to 'differential entropy') works only in a
severely restrictive context. We explain the key limitations, arguing that in
general, differential entropy does not correspond to residual entropy. Given
that the concept of residual entropy as collective ignorance transcends these
limitations, we identify two correspondingly robust, covariantly-defined
constructs: a 'strip wedge' associated with boundary observers and a 'rim
wedge' associated with bulk observers. These causal sets are well-defined in
arbitrary time-dependent asymptotically AdS spacetimes in any number of
dimensions. We discuss their relation, specifying a criterion for when these
two constructs coincide, and prove an inclusion relation for a general case. We
also speculate about the implications for residual entropy. Curiously, despite
each construct admitting a well-defined finite quantity related to the areas of
associated bulk surfaces, these quantities are not in one-to-one correspondence
with the defining regions of unknown. This has nontrivial implications about
holographic measures of quantum information.Comment: 35 pages, 6 figures; v2: references added, matches the published
  versio
Planck intermediate results. XXIV. Constraints on variation of
  fundamental constants

Any variation of the fundamental physical constants, and more particularly of
the fine structure constant, $\alpha$, or of the mass of the electron, $m_e$,
would affect the recombination history of the Universe and cause an imprint on
the cosmic microwave background angular power spectra. We show that the Planck
data allow one to improve the constraint on the time variation of the fine
structure constant at redshift $z\sim 10^3$ by about a factor of 5 compared to
WMAP data, as well as to break the degeneracy with the Hubble constant, $H_0$.
In addition to $\alpha$, we can set a constraint on the variation of the mass
of the electron, $m_{\rm e}$, and on the simultaneous variation of the two
constants. We examine in detail the degeneracies between fundamental constants
and the cosmological parameters, in order to compare the limits obtained from
Planck and WMAP and to determine the constraining power gained by including
other cosmological probes. We conclude that independent time variations of the
fine structure constant and of the mass of the electron are constrained by
Planck to ${\Delta\alpha}/{\alpha}= (3.6\pm 3.7)\times10^{-3}$ and ${\Delta
m_{\rm e}}/{m_{\rm e}}= (4 \pm 11)\times10^{-3}$ at the 68% confidence level.
We also investigate the possibility of a spatial variation of the fine
structure constant. The relative amplitude of a dipolar spatial variation of
$\alpha$ (corresponding to a gradient across our Hubble volume) is constrained
to be $\delta\alpha/\alpha=(-2.4\pm 3.7)\times 10^{-2}$.Comment: 25 pages, 16 figures, 11 tables, submitted to A&
Neutral Higgs Sector of the MSSM without $R_p$

We analyse the neutral scalar sector of the MSSM without R-parity. Our
analysis is performed for a one-generation model in terms of
``basis-independent'' parameters, and includes one-loop corrections due to
large yukawa couplings. We concentrate on the consequences of large $R_p$
violating masses in the soft sector, which mix the Higgses with the sleptons,
because these are only constrained by their one-loop contributions to neutrino
masses. We focus on the effect of $R_p$-violation on the Higgs mass and
branching ratios. We find that the experimental lower bound on the lightest
CP-even Higgs in this model can be lower than in the MSSM.Comment: minor changes, version to appear in journa
On topological 2D string and intersection theory

The topological description of 2D string theory at the self-dual radius is studied in the algebro-geometrical formulation of the A_{k+1} topological models at k=-3. Genus zero correlators of tachyons and their gravitational descendants are computed as intersection numbers on moduli space and compared to 2D string results. The interpretation of negative momentum tachyons as gravitational descendants of the cosmological constant, as well as modifications of this, is shown to imply a disagreement between 2D string correlators and the associated intersection numbers
Quantum chains with a Catalan tree pattern of conserved charges: the
  $\Delta = -1$ XXZ model and the isotropic octonionic chain

A class of quantum chains possessing a family of local conserved charges with
a Catalan tree pattern is studied. Recently, we have identified such a
structure in the integrable $SU(N)$-invariant chains. In the present work we
find sufficient conditions for the existence of a family of charges with this
structure in terms of the underlying algebra. Two additional systems with a
Catalan tree structure of conserved charges are found. One is the spin 1/2 XXZ
model with $\Delta=-1$. The other is a new octonionic isotropic chain,
generalizing the Heisenberg model. This system provides an interesting example
of an infinite family of noncommuting local conserved quantities.Comment: 20 pages in plain TeX; uses macro harvma
Analytic tools to brane technology in N=2 gauge theories with matter

Exact solutions to the low-energy effective action (LEEA) of the
four-dimensional N=2 supersymmetric gauge field theories are known to be
obtained either by quantum field theory methods from S-duality in the
Seiberg-Witten approach, or by the Type-IIA superstring/M-Theory methods of
brane technology. After a brief review of the standard field-theoretical
results for the N=2 gauge (Seiberg-Witten) LEEA, we consider a
field-theoretical derivation of the exact hypermultiplet LEEA by using the N=2
harmonic superspace methods. We illustrate our techniques on a number of
explicit examples. Our main purpose, however, is to discuss the existing
analytical (calculational) support for the alternative methods of brane
technology. We summarize known exact solutions to the eleven-dimensional and
ten-dimensional type-IIA supergravities, which describe classical
configurations of intersecting BPS branes with eight supercharges relevant to
the non-perturbative N=2 gauge field theory with fundamental hypermultiplet
matter. The crucial role of M-Theory in providing a classical resolution of
singularities in the ten-dimensional (Type-IIA superstring) brane picture, as
well as the N=2 extended supersymmetry in four dimensions, are made manifest.
The two approaches to a derivation of the exact N=2 gauge theory LEEA are thus
seen to be complementary to each other and mutually dependent.Comment: 80 pages, LaTeX, 7 pictures, macros include
Strangeness Production in Proton-Proton Collisions Close to Threshold

Exclusive data on the reactions pp -> ppK+K- and pp -> pK+ Lambda/Sigma0 have
been taken at the cooler synchrotron COSY close to threshold. At equal excess
energies, an enhancement of the Lambda/Sigma0 ratio by one order of magnitude
has been observed compared to data at higher excess energies. New results
obtained at the COSY-11 facility explore the transition region between this
low-energy Sigma0 suppression and excess energies of 60 MeV. A first total
cross section for elementary antikaon production below the phi threshold has
been determined, two orders of magnitude smaller compared to kaon production at
the same excess energy.Comment: 4 pages, 2 figures, Talk given by P. Moskal at 16th International
  Conference on Particles and Nuclei (PANIC 02), Osaka, Japan, 30 Sep - 4 Oct
  200