pinecone/core-2020-05-10-deduplication huggingface dataset:
More Benefits of Semileptonic Rare B Decays at Low Recoil: CP Violation

We present a systematic analysis of the angular distribution of Bbar ->
Kbar^\ast (-> Kbar pi) l^+ l^- decays with l = e, mu in the low recoil region
(i.e. at high dilepton invariant masses of the order of the mass of the
b-quark) to account model-independently for CP violation beyond the Standard
Model, working to next-to-leading order QCD. From the employed heavy quark
effective theory framework we identify the key CP observables with reduced
hadronic uncertainties. Since some of the CP asymmetries are CP-odd they can be
measured without B-flavour tagging. This is particularly beneficial for
Bbar_s,B_s -> phi(-> K^+ K^-) l^+ l^- decays, which are not self-tagging, and
we work out the corresponding time-integrated CP asymmetries. Presently
available experimental constraints allow the proposed CP asymmetries to be
sizeable, up to values of the order ~ 0.2, while the corresponding Standard
Model values receive a strong parametric suppression at the level of O(10^-4).
Furthermore, we work out the allowed ranges of the short-distance (Wilson)
coefficients C_9,C_10 in the presence of CP violation beyond the Standard Model
but no further Dirac structures. We find the Bbar_s -> mu^+ mu^- branching
ratio to be below 9*10^-9 (at 95% CL). Possibilities to check the performance
of the theoretical low recoil framework are pointed out.Comment: 18 pages, 3 fig.; 1 reference and comment on higher order effects
  added; EOS link fixed. Minor adjustments to Eqs 4.1-4.3 to match the (lower)
  q^2-cut as given in paper. Main results and conclusions unchanged; v3+v4:
  treatment of exp. uncert. in likelihood-function in EOS fixed and constraints
  from scan on C9,C10 updated (Fig 2,3 and Eqs 3.2,3.3). Main results and
  conclusions absolutely unchange
Maximal supergravity in three dimensions: supergeometry and differential
  forms

The maximal supergravity theory in three dimensions, which has local SO(16)
and rigid $E_8$ symmetries, is discussed in a superspace setting starting from
an off-shell superconformal structure. The on-shell theory is obtained by
imposing further constraints. It is essentially a non-linear sigma model that
induces a Poincar\'e supergeometry that is described in detail. The possible
$p$-form field strengths, for $p=2,3,4$, are explicitly constructed using
supersymmetry and $E_8$. The gauged theory is also discussed.Comment: 27 pages. Small changes to the text; added reference
Flavour physics constraints in the BMSSM

We study the implications of the presence of the two leading-order,
non-renormalizable operators in the Higgs sector of the MSSM to flavour physics
observables. We identify the constraints of flavour physics on the parameters
of the BMSSM when we: a) focus on a region of parameters for which electroweak
baryogenesis is feasible, b) use a CMSSM-like parametrization, and c) consider
the case of a generic NUHM-type model. We find significant differences as
compared to the standard MSSM case.Comment: 22 pages, 7 figure
The Conformal Sector of F-theory GUTs

D3-brane probes of exceptional Yukawa points in F-theory GUTs are natural
hidden sectors for particle phenomenology. We find that coupling the probe to
the MSSM yields a new class of N = 1 conformal fixed points with computable
infrared R-charges. Quite surprisingly, we find that the MSSM only weakly mixes
with the strongly coupled sector in the sense that the MSSM fields pick up
small exactly computable anomalous dimensions. Additionally, we find that
although the states of the probe sector transform as complete GUT multiplets,
their coupling to Standard Model fields leads to a calculable threshold
correction to the running of the visible sector gauge couplings which improves
precision unification. We also briefly consider scenarios in which SUSY is
broken in the hidden sector. This leads to a gauge mediated spectrum for the
gauginos and first two superpartner generations, with additional contributions
to the third generation superpartners and Higgs sector.Comment: v2: 51 pages, 2 figures, remark added, typos correcte
Diagonal deformations of thin center vortices and their stability in
  Yang-Mills theories

The importance of center vortices for the understanding of the confining
properties of SU(N) Yang-Mills theories is well established in the lattice.
However, in the continuum, there is a problem concerning the relevance of
center vortex backgrounds. They display the so called Savvidy-Nielsen-Olesen
instability, associated with a gyromagnetic ratio $g^{(b)}_m=2$ for the
off-diagonal gluons.
  In this work, we initially consider the usual definition of a {\it thin}
center vortex and rewrite it in terms of a local color frame in SU(N)
Yang-Mills theories. Then, we define a thick center vortex as a diagonal
deformation of the thin object. Besides the usual thick background profile,
this deformation also contains a frame defect coupled with gyromagnetic ratio
$g^{(d)}_m=1$, originated from the charged sector. As a consequence, the
analysis of stability is modified. In particular, we point out that the defect
should stabilize a vortex configuration formed by a pair of straight components
separated by an appropriate finite distance.Comment: 20 pages, LaTe
Some analytic results for two-loop scattering amplitudes

We present analytic results for the finite diagrams contributing to the
two-loop eight-point MHV scattering amplitude of planar N=4 SYM. We use a
recently proposed representation for the integrand of the amplitude in terms of
(momentum) twistors and focus on a restricted kinematics in which the answer
depends only on two independent cross-ratios. The theory of motives can be used
to vastly simplify the results, which can be expressed as simple combinations
of classical polylogarithms.Comment: 18 page
N=2 AdS supergravity and supercurrents

We consider the minimal off-shell formulation for four-dimensional N=2
supergravity with a cosmological term, in which the second compensator is an
improved tensor multiplet. We use it to derive a linearized supergravity action
(and its dual versions) around the anti-de Sitter (AdS) background in terms of
three N=2 off-shell multiplets: an unconstrained scalar superfield, vector and
tensor multiplets. This allows us to deduce the structure of the supercurrent
multiplet associated with those supersymmetric theories which naturally couple
to the supergravity formulation chosen, with or without a cosmological term.
Finally, our linearized N=2 AdS supergravity action is reduced to N=1
superspace. The result is a sum of two N=1 linearized actions describing (i)
old minimal supergravity; and (ii) an off-shell massless gravitino multiplet.
We also derive dual formulations for the massless N=1 gravitino multiplet in
AdS. As a by-product of our consideration, we derive the consistent
supergravity extension of the N=1 supercurrent multiplet advocated recently by
Komargodski and Seiberg.Comment: 53 pages; v2. typos corrected, references adde
Searching for sterile neutrinos in ice

Oscillation interpretation of the results from the LSND, MiniBooNE and some
other experiments requires existence of sterile neutrino with mass $\sim 1$ eV
and mixing with the active neutrinos $|U_{\mu 0}|^2 \sim (0.02 - 0.04)$. It has
been realized some time ago that existence of such a neutrino affects
significantly the fluxes of atmospheric neutrinos in the TeV range which can be
tested by the IceCube Neutrino Observatory. In view of the first IceCube data
release we have revisited the oscillations of high energy atmospheric neutrinos
in the presence of one sterile neutrino. Properties of the oscillation
probabilities are studied in details for various mixing schemes both
analytically and numerically. The energy spectra and angular distributions of
the $\nu_\mu-$events have been computed for the simplest $\nu_s-$mass, and
$\nu_s - \nu_\mu$ mixing schemes and confronted with the IceCube data. An
illustrative statistical analysis of the present data shows that in the
$\nu_s-$mass mixing case the sterile neutrinos with parameters required by
LSND/MiniBooNE can be excluded at about $3\sigma$ level. The $\nu_s- \nu_\mu$
mixing scheme, however, can not be ruled out with currently available IceCube
data.Comment: 41 pages, 16 figures. Accepted for publication in JHEP. Minor changes
  from the previous versio
Gravitational Chern-Simons Lagrangians and black hole entropy

We analyze the problem of defining the black hole entropy when Chern-Simons
terms are present in the action. Extending previous works, we define a general
procedure, valid in any odd dimensions both for purely gravitational CS terms
and for mixed gauge-gravitational ones. The final formula is very similar to
Wald's original formula valid for covariant actions, with a significant
modification. Notwithstanding an apparent violation of covariance we argue that
the entropy formula is indeed covariant.Comment: 39 page
Explicit BCJ Numerators from Pure Spinors

We derive local kinematic numerators for gauge theory tree amplitudes which
manifestly satisfy Jacobi identities analogous to color factors. They naturally
emerge from the low energy limit of superstring amplitudes computed with the
pure spinor formalism. The manifestation of the color--kinematics duality is a
consequence of the superstring computation involving no more than (n-2)!
kinematic factors for the full color dressed n-point amplitude. The bosonic
part of these results describe gluon scattering independent on the number of
supersymmetries and captures any N^kMHV helicity configuration after
dimensional reduction to D=4 dimensions.Comment: 32 pages, harvma
Top quark tensor couplings

We compute the real and imaginary parts of the one-loop electroweak contributions to the left and right tensorial anomalous couplings of the tbW vertex in the Standard Model (SM). For both tensorial couplings we find that the real part of the electroweak SM correction is close to 10 of the leading contribution given by the QCD gluon exchange. We also find that the electroweak real and imaginary parts for the anomalous right coupling are almost of the same order of magnitude. The one loop SM prediction for the real part of the left coupling is close to the 3σ discovery limit derived from b→sγ. Besides, taking into account that the predictions of new physics interactions are also at the level of a few percents when compared with the one loop QCD gluon exchange, these electroweak corrections should be taken into account in order to disentangle new physics effects from the standard ones. These anomalous tensorial couplings of the top quark will be investigated at the LHC in the near future where sensitivity to these contributions may be achieved
Shock waves in strongly coupled plasmas II

In a recent paper we have analyzed the AdS/CFT duals to shock waves
propagating in the N=4 plasma. Here we study further properties of the system.
In the gravity description we consider the properties of the dual black holes,
showing in particular that they are stationary black holes with expanding
horizons. This is possible because the horizon is not compact; in the fluid,
this corresponds to the situation when entropy is being produced and carried
away to infinity. We also consider shocks in dimensionalities d other than four
and find that, for plasmas whose duals are given by asymptotically AdS spaces,
the exponential tail of the shock on the supersonic side shrinks as
gamma^(-2/d) as the velocity approaches the speed of light (the Lorentz factor
gamma goes to infinity). This generalizes the behavior gamma^(-1/2) we have
found previously for d=4. Finally, we consider corrugations of the shock front
and show that the shock is stable under such perturbations. There are, however,
long lived modes, excitations of which describe generation of sound by the
shock wave, the energy for this being provided by the incoming fluid.Comment: 42 pages, 7 figure
Discovery reach for generic supersymmetry at the LHC: MT2 versus missing
  transverse momentum selections for pMSSM searches

Different search strategies for supersymmetry have been employed by the LHC
general-purpose experiments using early data. As proven by their early results,
these strategies are promising, but raise the question of how well they will
generalize for the future. We address this question by studying two thousand
phenomenological minimal supersymmetric standard model parameter space points
that come from a fit to indirect and cosmological data. We examine the 5 sigma
discoverability of the points employing a typical ATLAS-type search based on
missing transverse momentum (MET), a search based on an optimised MT2 cut and a
combination of the two, taking into account standard model backgrounds. The
discovery reach of the strategies can depend strongly on the systematic
uncertainty in the background, subject to the stringency of the cuts and the
details of the background simulation. By combining the MET and MT2 based
strategies, with an integrated luminosity of 1 fb^-1 (10 fb^-1) at 7 TeV, 4-8%
(42%) of the points are discoverable, depending on the systematic uncertainty
on the background. At 14 TeV and with 10 fb^-1, 96% of the points are
discoverable. While the majority of points can be discovered by both strategies
at sqrt{s} = 14 TeV and with 1 fb^-1, there are some that are left undiscovered
by a MET search strategy, but which are discovered by the MT2 strategy, and
vice versa, therefore it is essential that one performs both in parallel. We
discuss some of the factors that can make points more difficult to observe.Comment: 22 pages, 7 figures, 3 table
Minimal models with light sterile neutrinos

We study the constraints imposed by neutrino oscillation experiments on the minimal extensions of the Standard Model (SM) with nR gauge singlet fermions ('right-handed neutrinos'), that can account for neutrino masses. We consider the most general coupling to SM fields of the new fields, in particular those that break lepton number and we do not assume any a priori hierarchy in the mass parameters. We proceed to analyze these models starting from the lowest level of complexity, defined by the number of extra fermionic degrees of freedom. The simplest choice that has enough free parameters in principle (i.e. two mass differences and two angles) to explain the confirmed solar and atmospheric oscillations corresponds to nR=1. This minimal choice is shown to be excluded by data. The next-to-minimal choice corresponds to nR=2. We perform a systematic study of the full parameter space in the limit of degenerate Majorana masses by requiring that at least two neutrino mass differences correspond to those established by solar and atmospheric oscillations. We identify several types of spectra that can fit long-baseline reactor and accelerator neutrino oscillation data, but fail in explaining solar and/or atmospheric data. The only two solutions that survive are the expected seesaw and quasi-Dirac regions, for which we set lower and upper bounds respectively on the Majorana mass scale. Solar data from neutral current measurements provide essential information to constrain the quasi-Dirac region. The possibility to accommodate the LSND/MiniBoone and reactor anomalies, and the implications for neutrinoless double-beta decay and tritium beta decay are briefly discussed
Holographic fermions in charged Gauss-Bonnet black hole

We study the properties of the Green's functions of the fermions in charged
Gauss-Bonnet black hole. What we want to do is to investigate how the presence
of Gauss-Bonnet coupling constant $\alpha$ affects the dispersion relation,
which is a characteristic of Fermi or non-Fermi liquid, as well as what
properties such a system has, for instance, the Particle-hole (a)symmetry. One
important result of this research is that we find for $q=1$, the behavior of
this system is different from that of the Landau Fermi liquid and so the system
can be candidates for holographic dual of generalized non-Fermi liquids. More
importantly, the behavior of this system increasingly similar to that of the
Landau Fermi liquid when $\alpha$ is approaching its lower bound. Also we find
that this system possesses the Particle-hole asymmetry when $q\neq 0$, another
important characteristic of this system. In addition, we also investigate
briefly the cases of the charge dependence.Comment: 22 pages, 6 figures; version published in JHE
Constructing near-horizon geometries in supergravities with hidden
  symmetry

We consider the classification of near-horizon geometries in a general
two-derivative theory of gravity coupled to abelian gauge fields and uncharged
scalars in four and five dimensions, with one and two commuting rotational
symmetries respectively. Assuming that the theory of gravity reduces to a 3d
non-linear sigma model (as is typically the case for ungauged supergravities),
we show that the functional form of any such near-horizon geometry may be
determined. As an example we apply this to five dimensional minimal
supergravity. We also construct an example of a five parameter near-horizon
geometry solution to this theory with S^1 X S^2 horizon topology. We discuss
its relation to the near-horizon geometries of the yet to be constructed
extremal black rings with both electric and dipole charges.Comment: Latex, 30 pages. v2: discussion in section 5 modified and improved,
  other minor changes, references adde
Neutral Gauge Boson Contributions to the Dimuon Charge Asymmetry in B
  Decays

Recently, the D0 Collaboration measured the CP-violating like-sign dimuon
charge asymmetry in neutral B decays, finding a 3.2sigma difference from the
standard-model (SM) prediction. A non-SM charge asymmetry a_sl^s suggests a
new-physics (NP) contribution to Bs-Bsbar mixing. In this case, in order to
explain the measured value of a_sl^s within its 1sigma range, NP must be
present in Gamma_12^s, the absorptive part of the mixing. In this paper, we
examine whether such an explanation is possible in models with flavor-changing
Z (ZFCNC) or Z' (Z'FCNC) gauge bosons. The models must also reproduce the
measured values of the indirect CP asymmetry S_psi-phi in Bs -> J/psi phi, and
Delta Gamma_s, the Bs-Bsbar width difference. We find that the ZFCNC model
cannot reproduce the present measured values of S_psi-phi and a_sl^s within
their 1sigma ranges. On the other hand, in the Z'FCNC model, the values of all
three observables can be simultaneously reproduced.Comment: 18 pages, 7 figures, JHEP format. Some ZFCNC equations corrected,
  ZFCNC analysis redone, references added, conclusions unchange
Testing String Vacua in the Lab: From a Hidden CMB to Dark Forces in
  Flux Compactifications

We perform a detailed analysis of the phenomenological properties of hidden
Abelian gauge bosons with a kinetic mixing with the ordinary photon within type
IIB flux compactifications. We study the interplay between moduli stabilisation
and the Green-Schwarz mechanism that gives mass to the hidden photon paying
particular attention to the role of D-terms. We present two generic classes of
explicit Calabi-Yau examples with an isotropic and an anisotropic shape of the
extra dimensions showing how the last case turns out to be very promising to
make contact with current experiments. In fact, anisotropic compactifications
lead naturally to a GeV-scale hidden photon ("dark forces" that can be searched
for in beam dump experiments) for an intermediate string scale; or even to an
meV-scale hidden photon (which could lead to a "hidden CMB" and can be tested
by light-shining-through-a-wall experiments) in the case of TeV-scale strings.Comment: 37 pages, 3 figures. v2 some typos correcte
Effect of r averaging on Chiral Anomaly in Lattice QCD with Wilson
  Fermion: Finite volume and cutoff effects

We demonstrate the effectiveness of averaging over the Wilson parameter r
(which has been proposed earlier) in removing the cutoff effects of naive
Wilson fermions in both the anomaly term and the pseudoscalar density term in
the flavor singlet axial Ward identity at O(g^2) involving slowly varying
background gauge fields. We show that it is the physical fermion contribution
which is largely influenced by the r averaging. We have studied the possible
interplay between finite size and cutoff effects by investigating in detail
naive, O(a) improved and OStm Wilson fermion cases for a range of volumes and
lattice fermion mass (am). For naive Wilson fermions r averaging is shown to
remove the effects of the interplay. We have shown that for the pseudoscalar
density term to O (g^2) the lattice result differs from the continuum result by
exhibiting considerable am dependence which appears to be a manifestation of
cutoff effects with naive Wilson fermion. The pseudoscalar density term to
O(g^2) is shown to be almost independent of am when r-averaging is performed.Comment: 14 pages, 13 figures, revise
A local Monte Carlo framework for coherent QCD parton energy loss

Monte Carlo (MC) simulations are the standard tool for describing jet-like
multi-particle final states. To apply them to the simulation of medium-modified
jets in heavy ion collisions, a probabilistic implementation of medium-induced
quantum interference effects is needed. Here, we analyze in detail how the
quantum interference effects included in the BDMPS-Z formalism of
medium-induced gluon radiation can be implemented in a quantitatively
controlled, local probabilistic parton cascade. The resulting MC algorithm is
formulated in terms of elastic and inelastic mean free paths, and it is by
construction insensitive to the IR and UV divergences of the total elastic and
inelastic cross sections that serve as its basic building blocks in the
incoherent limit. Interference effects are implemented by reweighting gluon
production histories as a function of the number of scattering centers that act
within the gluon formation time. Unlike existing implementations based on gluon
formation time, we find generic arguments for why a quantitative implementation
of quantum interference cannot amount to a mere dead-time requirement for
subsequent gluon production. We validate the proposed MC algorithm by comparing
MC simulations with parametric dependencies and analytical results of the
BDMPS-Z formalism. In particular, we show that the MC algorithm interpolates
correctly between analytically known limiting cases for totally coherent and
incoherent gluon production, and that it accounts quantitatively for the
medium-induced gluon energy distribution and the resulting average parton
energy loss. We also verify that the MC algorithm implements the transverse
momentum broadening of the BDMPS-Z formalism. We finally discuss why the
proposed MC algorithm provides a suitable starting point for going beyond the
approximations of the BDMPS-Z formalism.Comment: 49 pages, 13 figures, v2: typos correcte
Properties of Schroedinger Black Holes from AdS Space

Properties of Schroedinger black holes are derived from AdS black holes
expressed in light-cone coordinates with a particular normalization. The
advantages of this method over the direct analysis of the Schroedinger geometry
are the simplicity and the well-defined Brown-York procedure with the standard
counterterms. The method is demonstrated for several physical interests,
including the computation of the DC conductivity and the derivation of the
R-charged black hole thermodynamic properties.Comment: 27 pages, 4 figures, minor changes, published versio
Non-perturbative transitions among intersecting-brane vacua

We investigate the transmutation of D-branes into Abelian magnetic backgrounds on the world-volume of higher-dimensional branes, within the framework of global models with compact internal dimensions. The phenomenon, T-dual to brane recombination in the intersecting-brane picture, shares some similarities to inverse small-instanton transitions in non-compact spaces, though in this case the Abelian magnetic background is a consequence of the compactness of the internal manifold, and is not ascribed to a zero-size non-Abelian instanton growing to maximal size. We provide details of the transition in various supersymmetric orientifolds and non-supersymmetric tachyon-free vacua with Brane Supersymmetry Breaking, both from brane recombination and from a field theory Higgs mechanism viewpoints