pinecone/core-2020-05-10-deduplication huggingface dataset:
Distributed SUSY Breaking: Dark Energy, Newton's Law and the LHC

We identify the underlying symmetry mechanism that suppresses the low-energy
effective 4D cosmological constant within 6D supergravity models, leading to
results suppressed by powers of the KK scale relative to the much larger masses
associated with particles localized on codimension-2 branes. In these models
the conditions for unbroken supersymmetry can be satisfied locally everywhere
within the extra dimensions, but are obstructed by global conditions like flux
quantization or the mutual inconsistency of boundary conditions at the various
branes. Consequently quantities forbidden by supersymmetry cannot be nonzero
until wavelengths of order the KK scale are integrated out, since only such
long wavelength modes see the entire space and so know that supersymmetry
breaks. We verify these arguments by extending earlier rugby-ball calculations
of one-loop vacuum energies to more general pairs of branes within two warped
extra dimensions. The predicted effective 4D vacuum energy density can be of
order C (m Mg/4 pi Mp)^4, where Mg (Mp) is the rationalized 6D (4D) Planck
scale and m is the heaviest brane-localized particle. Numerically this is C
(5.6 x 10^{-5} eV)^4 if we take m = 173 GeV and take Mg as small as possible
(10 TeV corresponding to KK size r < 1 micron), consistent with supernova
bounds. C is a constant depending on details of the bulk spectrum, which could
be ~ 500 for each of hundreds of fields. The value C ~ 6 x 10^6 gives the
observed Dark Energy density
Holographic probes of collapsing black holes

We continue the programme of exploring the means of holographically decoding
the geometry of spacetime inside a black hole using the gauge/gravity
correspondence. To this end, we study the behaviour of certain extremal
surfaces (focusing on those relevant for equal-time correlators and
entanglement entropy in the dual CFT) in a dynamically evolving asymptotically
AdS spacetime, specifically examining how deep such probes reach. To highlight
the novel effects of putting the system far out of equilibrium and at finite
volume, we consider spherically symmetric Vaidya-AdS, describing black hole
formation by gravitational collapse of a null shell, which provides a
convenient toy model of a quantum quench in the field theory. Extremal surfaces
anchored on the boundary exhibit rather rich behaviour, whose features depend
on dimension of both the spacetime and the surface, as well as on the anchoring
region. The main common feature is that they reach inside the horizon even in
the post-collapse part of the geometry. In 3-dimensional spacetime, we find
that for sub-AdS-sized black holes, the entire spacetime is accessible by the
restricted class of geodesics whereas in larger black holes a small region near
the imploding shell cannot be reached by any boundary-anchored geodesic. In
higher dimensions, the deepest reach is attained by geodesics which (despite
being asymmetric) connect equal time and antipodal boundary points soon after
the collapse; these can attain spacetime regions of arbitrarily high curvature
and simultaneously have smallest length. Higher-dimensional surfaces can
penetrate the horizon while anchored on the boundary at arbitrarily late times,
but are bounded away from the singularity. We also study the details of length
or area growth during thermalization. While the area of extremal surfaces
increases monotonically, geodesic length is neither monotonic nor continuous.Comment: 44 pages + appendices, 21 figures; v2: references added, improved
  Discussion; v3: minor typos corrected, matches the published versio
Explicit computation of the electrostatic energy for an elliptical
  charged disc

This letter describes a method for obtaining an explicit expression for the
electrostatic energy of a charged elliptical infinitely thin disc. The charge
distribution is assumed to be polynomial. Such explicit values for this energy
are fundamental for assessing the accuracy of boundary element codes. The main
tools used are an extension of Copson's method and a diagonalization, given by
Leppington and Levine, of the single-layer potential operator associated with
the electrostatic potential created by a distribution of charges on the
elliptical disc
A Spitzer-IRS view of early-type galaxies with cuspy/core nuclei and
  with fast/slow rotation

The recent literature suggests that an evolutionary dichotomy exists for
early-type galaxies (Es and S0s, ETGs) whereby their central photometric
structure (cuspy versus core central luminosity profiles), and figure of
rotation (fast (FR) vs. slow (SR) rotators), are determined by whether they
formed by "wet" or "dry" mergers. We consider whether the mid infrared (MIR)
properties of ETGs, with their sensitivity to accretion processes in particular
in the last few Gyr (on average z < 0.2), can put further constraints on this
picture. We investigate a sample of 49 ETGs for which nuclear MIR properties
and detailed photometrical and kinematical classifications are available from
the recent literature. In the stellar light cuspy/core ETGs show a dichotomy
that is mainly driven by their luminosity. However in the MIR, the brightest
core ETGs show evidence that accretions have triggered both AGN and star
formation activity in the recent past, challenging a "dry" merger scenario. In
contrast, we do find, in the Virgo and Fornax clusters, that cuspy ETGs,
fainter than M$_{K_s}=-24$, are predominantly passively evolving in the same
epoch, while, in low density environments, they tend to be more active. A
significant and statistically similar fraction of both FR (38$^{+18}_{-11}$\%)
and SR (50$^{+34}_{-21}$\%) shows PAH features in their MIR spectra. Ionized
and molecular gas are also frequently detected. Recent star formation episodes
are then a common phenomenon in both kinematical classes, even in those
dominated by AGN activity, suggesting a similar evolutionary path in the last
few Gyr. MIR spectra suggest that the photometric segregation between cuspy and
core nuclei and the dynamical segregation between FR and SR must have
originated before z~0.2.Comment: Research Note, 8 pages, 3 figures, accepted for publication in A&A
  main Journa
Minimal $R+R^2$ Supergravity Models of Inflation Coupled to Matter

The supersymmetric extension of "Starobinsky" $R+\alpha R^2$ models of
inflation is particularly simple in the "new minimal" formalism of
supergravity, where the inflaton has no scalar superpartners. This paper is
devoted to matter couplings in such supergravity models. We show how in the new
minimal formalism matter coupling presents certain features absent in other
formalisms. In particular, for the large class of matter couplings considered
in this paper, matter must possess an R-symmetry, which is gauged by the vector
field which becomes dynamical in the "new minimal" completion of the $R+\alpha
R^2$ theory. Thus, in the dual formulation of the theory, where the gauge
vector is part of a massive vector multiplet, the inflaton is the superpartner
of the massive vector of a nonlinearly realized R-symmetry. The F-term
potential of this theory is of no-scale type, while the inflaton potential is
given by the D-term of the gauged R-symmetry. The absolute minimum of the
potential is always exactly supersymmetric, so in this class of models if
realistic vacua exist, they must be always metastable. We also briefly comment
on possible generalizations of the examples discussed here and we exhibit some
features of higher-curvature supergravity coupled to matter in the "old
minimal" formalism.Comment: 9 page
Searching for highly obscured AGN in the XMM-Newton serendipitous source
  catalog

The majority of active galactic nuclei (AGN) are obscured by large amounts of
absorbing material that makes them invisible at many wavelengths. X-rays, given
their penetrating power, provide the most secure way for finding these AGN. The
XMM-Newton serendipitous source catalog is the largest catalog of X-ray sources
ever produced; it contains about half a million detections. These sources are
mostly AGN. We have derived X-ray spectral fits for very many 3XMM-DR4 sources
($\gtrsim$ 114 000 observations, corresponding to $\sim$ 77 000 unique
sources), which contain more than 50 source photons per detector. Here, we use
a subsample of $\simeq$ 1000 AGN in the footprint of the SDSS area (covering
120 deg$^2$) with available spectroscopic redshifts. We searched for highly
obscured AGN by applying an automated selection technique based on X-ray
spectral analysis that is capable of efficiently selecting AGN. The selection
is based on the presence of either a) flat rest-frame spectra; b) flat observed
spectra; c) an absorption turnover, indicative of a high rest-frame column
density; or d) an Fe K$\alpha$ line with an equivalent width > 500 eV. We found
81 highly obscured candidate sources. Subsequent detailed manual spectral fits
revealed that 28 of them are heavily absorbed by column densities higher than
10$^{23}$ cm$^{-2}$. Of these 28 AGN, 15 are candidate Compton-thick AGN on the
basis of either a high column density, consistent within the 90% confidence
level with N$_{\rm H}$ $>$10$^{24}$ cm$^{-2}$, or a large equivalent width
(>500 eV) of the Fe K$\alpha$ line. Another six are associated with
near-Compton-thick AGN with column densities of $\sim$ 5$\times$10$^{23}$
cm$^{-2}$. A combination of selection criteria a) and c) for low-quality
spectra, and a) and d) for medium- to high-quality spectra, pinpoint highly
absorbed AGN with an efficiency of 80%.Comment: 18 pages, 10 figures, accepted for publication in A&
Inelastic Dissipation in Tumbling Asteroids and Comets

Asteroids and comets dissipate energy when they rotate about the axis different from the axis of the maximal moment of inertia. We show that the most efficient internal relaxation happens at the double frequency of body's tumbling. Therefore the earlier estimates that ignore double frequency input underestimate the internal relaxation in asteroids and comets. We show that the Earth seismological data may poorly represent acoustic properties of asteroids and comet as internal relaxation increases in the presence of moisture. At the same time owing to non-linearlity of inelastic relaxation small angle nutations can persist for very long time spans
Resonant Amplification of Electromagnetic Fields

We investigate the possibility that electromagnetic fluctuations are amplified in an expanding universe by parametric resonance, during the oscillatory regime of a scalar field to which they are coupled. We examine two toy model couplings: scalar electrodynamics and axion electrodynamics. In both models, electromagnetic fluctuations undergo exponential instabilities. We discuss how plasma effects can counteract the resonance, but we argue that in some cases the resonance will persist and that hence this mechanism could have some relevance for the problem of large scale primordial magnetic fields
The BV-algebra structure of W_3 cohomology

We summarize some recent results obtained in collaboration with J. McCarthy
on the spectrum of physical states in $W_3$ gravity coupled to $c=2$ matter. We
show that the space of physical states, defined as a semi-infinite (or BRST)
cohomology of the $W_3$ algebra, carries the structure of a BV-algebra. This
BV-algebra has a quotient which is isomorphic to the BV-algebra of polyvector
fields on the base affine space of $SL(3,C)$. Details have appeared elsewhere.
[Published in the proceedings of "Gursey Memorial Conference I: Strings and
Symmetries," Istanbul, June 1994, eds. G. Aktas et al., Lect. Notes in Phys.
447, (Springer Verlag, Berlin, 1995)]Comment: 8 pages; uses macros tables.tex and amssym.def (version 2.1 or later
Moduli Spaces of D-branes in CFT-backgrounds

D-branes in curved backgrounds can be treated with techniques of boundary
conformal field theory. We discuss the influence of scalar condensates on such
branes, i.e. perturbations of boundary conditions by marginal boundary
operators. A general criterion is presented that guarantees a boundary
perturbation to be truly marginal in all orders of perturbation theory. Our
results on boundary deformations have several interesting applications which
are sketched at the end of this note.Comment: 8 pages, late
Properties of the Michaelis-Menten Mechanism in Phase Space

We study the two-dimensional reduction of the Michaelis-Menten reaction of
enzyme kinetics. First, we prove the existence and uniqueness of a slow
manifold between the horizontal and vertical isoclines. Second, we determine
the concavity of all solutions in the first quadrant. Third, we establish the
asymptotic behaviour of all solutions near the origin, which generally is not
given by a Taylor series. Finally, we determine the asymptotic behaviour of the
slow manifold at infinity.Comment: 29 pages, 8 figures, corrected a few typos and incorporated reviewer
  suggestion
On Fuglede's conjecture and the existence of universal spectra

Recent methods developed by Tao \cite{tao}, Kolountzakis and Matolcsi
\cite{nspec} have led to counterexamples to Fugelde's Spectral Set Conjecture
in both directions. Namely, in $\RR^5$ Tao produced a spectral set which is not
a tile, while Kolountzakis and Matolcsi showed an example of a non-spectral
tile. In search of lower dimensional non-spectral tiles we were led to
investigate the Universal Spectrum Conjecture (USC) of Lagarias and Wang
\cite{lagwang}. In particular, we prove here that the USC and the ``tile $\to$
spectral'' direction of Fuglede's conjecture are equivalent in any dimensions.
Also, we show by an example that the sufficient condition of Lagarias and
Szab\'o \cite{lagszab} for the existence of universal spectra is not necessary.
This fact causes considerable difficulties in producing lower dimensional
examples of tiles which have no spectra. We overcome these difficulties by
invoking some ideas of R\'ev\'esz and Farkas \cite{revfark}, and obtain
non-spectral tiles in $\RR^3$.
  Fuglede's conjecture and the Universal Spectrum Conjecture remains open in 1
and 2 dimensions. The 1 dimensional case is closely related to a number
theoretical conjecture on tilings by Coven and Meyerowitz \cite{covmey}.Comment: 12 page
The relativistic continuum Hartree-Bogoliubov description of
  charge-changing cross section for C,N,O and F isotopes

The ground state properties including radii, density distribution and one
neutron separation energy for C, N, O and F isotopes up to the neutron drip
line are systematically studied by the fully self-consistent microscopic
Relativistic Continuum Hartree-Bogoliubov (RCHB) theory. With the proton
density distribution thus obtained, the charge-changing cross sections for C,
N, O and F isotopes are calculated using the Glauber model. Good agreement with
the data has been achieved. The charge changing cross sections change only
slightly with the neutron number except for proton-rich nuclei. Similar trends
of variations of proton radii and of charge changing cross sections for each
isotope chain is observed which implies that the proton density plays important
role in determining the charge-changing cross sections.Comment: 10 pages, 4 figure
Straight macroscopic magnetic guide for cold atom interferometer

We demonstrate a macroscopic magnetic guide for cold atom interferometry, where the magnetic guiding field is generated by a symmetrical array of racetrack coils of copper tape. This system represents a conceptual advance over previous guided atom interferometers based on nonsymmetrical geometries because the symmetry provides a much lower magnetic field curvature per fixed length than equivalent nonsymmetrical geometries, permitting a decrease in system length without increasing the decoherence rate associated with field curvature. We realized a magnetic guide a few cm away from each coil, where smooth translation of the guided atoms is achieved by changing the currents in second array of the multiple-conductor tape.Physic
Ozone oxidation methods for aluminium oxide formation : application to low-voltage organic transistors

Four atmospheric pressure ozone oxidation methods were used to produce ultra-thin layers of aluminium oxide for organic thin-film transistors. They are UV/ozone oxidation in ambient (UV-AA) and dry (UV-DA) air, UV/ozone oxidation combined with high-voltage discharge-generated ozone in dry air (UV+O3-DA), and discharge-generated ozone in dry air (O3-DA). The lack of the high-energy UV photons during the O3-DA oxidation led to low relative permittivity and high leakage current density of the AlOx layer that rendered this method unsuitable for transistor dielectrics. Although this oxidation method led to the incorporation of oxygen into the film, the FTIR confirmed an increased concentration of the subsurface oxygen while the XPS showed the highest portion of the unoxidized Al among all four methods. The remaining three oxidation methods produced AlOx films with thicknesses in excess of 7 nm (2-hour oxidation time), relative permittivity between 6.61 and 7.25, and leakage current density of (1-7)x10-7 A/cm2 at 2 MV/cm, and were successfully implemented into organic thin-film transistors based on pentacene and DNTT. The presence of –OH groups in all oxides is below the detection limit, while some carbon impurities appear to be incorporated
230 GHz VLBI observations of M87: event-horizon-scale structure at the
  enhanced very-high-energy $\rm \gamma$-ray state in 2012

We report on 230 GHz (1.3 mm) VLBI observations of M87 with the Event Horizon
Telescope using antennas on Mauna Kea in Hawaii, Mt. Graham in Arizona and
Cedar Flat in California. For the first time, we have acquired 230 GHz VLBI
interferometric phase information on M87 through measurement of closure phase
on the triangle of long baselines. Most of the measured closure phases are
consistent with 0$^{\circ}$ as expected by physically-motivated models for 230
GHz structure such as jet models and accretion disk models. The brightness
temperature of the event-horizon-scale structure is $\sim 1 \times 10^{10}$ K
derived from the compact flux density of $\sim 1$ Jy and the angular size of
$\sim 40 $ $\rm \mu$as $\sim$ 5.5 $R_{{\rm s}}$, which is broadly consistent
with the peak brightness of the radio cores at 1-86 GHz located within $\sim
10^2$ $R_{{\rm s}}$. Our observations occurred in the middle of an enhancement
in very-high-energy (VHE) $\rm \gamma$-ray flux, presumably originating in the
vicinity of the central black hole. Our measurements, combined with results of
multi-wavelength observations, favor a scenario in which the VHE region has an
extended size of $\sim$20-60 $R_{{\rm s}}$.Comment: 11 pages, 4 figures, accepted to Ap
Quasi-periodic oscillations in accreting magnetic white dwarfs II. The
  asset of numerical modelling for interpreting observations

Magnetic cataclysmic variables are close binary systems containing a strongly
magnetized white dwarf that accretes matter coming from an M-dwarf companion.
High-energy radiation coming from those objects is emitted from the accretion
column close to the white dwarf photosphere at the impact region. Its
properties depend on the characteristics of the white dwarf and an accurate
accretion column model allows the properties of the binary system to be
inferred, such as the white dwarf mass, its magnetic field, and the accretion
rate. We study the temporal and spectral behaviour of the accretion region and
use the tools we developed to accurately connect the simulation results to the
X-ray and optical astronomical observations. The radiation hydrodynamics code
Hades was adapted to simulate this specific accretion phenomena. Classical
approaches were used to model the radiative losses of the two main radiative
processes: bremsstrahlung and cyclotron. The oscillation frequencies and
amplitudes in the X-ray and optical domains are studied to compare those
numerical results to observational ones. Different dimensional formulae were
developed to complete the numerical evaluations. The complete characterization
of the emitting region is described for the two main radiative regimes: when
only the bremsstrahlung losses and when both cyclotron and bremsstrahlung
losses are considered. The effect of the non-linear cooling in- stability
regime on the accretion column behaviour is analysed. Variation in luminosity
on short timescales (~ 1 s quasi-periodic oscillations) is an expected
consequence of this specific dynamic. The importance of secondary shock
instability on the quasi-periodic oscillation phenomenon is discussed. The
stabilization effect of the cyclotron process is confirmed by our numerical
simulations, as well as the power distribution in the various modes of
oscillation.Comment: 13 pages, 13 figures, 2 tables. Accepted for publication in A&
WASP-54b, WASP-56b, and WASP-57b : three new sub-Jupiter mass planets from SuperWASP

We present three newly discovered sub-Jupiter mass planets from the SuperWASP survey: WASP-54b is a heavily bloated planet of mass 0.636+0.025-0.024MJ and radius 1.653+0.090-0.083RJ. It orbits a F9 star, evolving off the main sequence, every 3.69 days. Our MCMC fit of the system yields a slightly eccentric orbit (e = 0.067+0.033-0.025) for WASP-54b. We investigated further the veracity of our detection of the eccentric orbit for WASP-54b, and we find that it could be real. However, given the brightness of WASP-54 V = 10.42 mag, we encourage observations of a secondary eclipse to draw robust conclusions on both the orbital eccentricity and the thermal structure of the planet. WASP-56b and WASP-57b have masses of 0.571+0.034-0.035MJ and 0.672+0.049-0.046MJ, respectively; and radii of 1.092+0.035-0.033RJ for WASP-56b and 0.916+0.017-0.014RJ for WASP-57b. They orbit main sequence stars of spectral type G6 every 4.67 and 2.84 days, respectively. WASP-56b and WASP-57b show no radius anomaly and a high density possibly implying a large core of heavy elements; possibly as high as ~50 M⊕ in the case of WASP-57b. However,the composition of the deep interior of exoplanets remains still undetermined. Thus, more exoplanet discoveries such as the ones presented in this paper, are needed to understand and constrain giant planets’ physical properties.Publisher PDFPeer reviewe
The role of HOX genes in normal hematopoiesis and acute leukemia

The homeobox (HOX) genes are a highly conserved family of homeodomain-containing transcription factors that specify cell identity in early development and, subsequently, in a number of adult processes including hematopoiesis. The dysregulation of HOX genes is associated with a number of malignancies including acute myeloid leukemia (AML) and acute lymphoid leukemia (ALL), where they have been shown to support the immortalization of leukemic cells both as chimeric partners in fusion genes and when overexpressed in their wild-type form. This review covers our current understanding of the role of HOX genes in normal hematopoiesis, AML and ALL, with particular emphasis on the similarities and differences of HOX function in these contexts, their hematopoietic downstream gene targets and implications for therapy. © 2013 Macmillan Publishers Limited All rights reserved