3,018 research outputs found
Supersymmetric solutions of gauged five-dimensional supergravity with general matter couplings
We perform the characterization program for the supersymmetric configurations
and solutions of the , Supergravity Theory coupled to an
arbitrary number of vectors, tensors and hypermultiplets and with general
non-Abelian gaugins. By using the conditions yielded by the characterization
program, new exact supersymmetric solutions are found in the
model for the hyperscalars and with as the gauge group. The
solutions also content non-trivial vector and massive tensor fields, the latter
being charged under the U(1) sector of the gauge group and with selfdual
spatial components. These solutions are black holes with
near horizon geometry in the gauged version of the theory and for the ungauged
case we found naked singularities. We also analyze supersymmetric solutions
with only the scalars of the vector/tensor multiplets and the metric
as the non-trivial fields. We find that only in the null class the scalars
can be non-constant and for the case of constant we refine
the classification in terms of the contributions to the scalar potential.Comment: Minor changes in wording and some typos corrected. Version to appear
in Class. Quantum Grav. 38 page
All the timelike supersymmetric solutions of all ungauged d=4 supergravities
We determine the form of all timelike supersymmetric solutions of all N
greater or equal than 2, d=4 ungauged supergravities, for N less or equal than
4 coupled to vector supermultiplets, using the $Usp(n+1,n+1)-symmetric
formulation of Andrianopoli, D'Auria and Ferrara and the spinor-bilinears
method, while preserving the global symmetries of the theories all the way. As
previously conjectured in the literature, the supersymmetric solutions are
always associated to a truncation to an N=2 theory that may include
hypermultiplets, although fields which are eliminated in the truncations can
have non-trivial values, as is required by the preservation of the global
symmetry of the theories. The solutions are determined by a number of
independent functions, harmonic in transverse space, which is twice the number
of vector fields of the theory (n+1). The transverse space is flat if an only
if the would-be hyperscalars of the associated N=2 truncation are trivial.Comment: v3: Some changes in the introduction. Version to be published in JHE
All null supersymmetric backgrounds of N=2, D=4 gauged supergravity coupled to abelian vector multiplets
The lightlike supersymmetric solutions of N=2, D=4 gauged supergravity
coupled to an arbitrary number of abelian vector multiplets are classified
using spinorial geometry techniques. The solutions fall into two classes,
depending on whether the Killing spinor is constant or not. In both cases, we
give explicit examples of supersymmetric backgrounds. Among these BPS
solutions, which preserve one quarter of the supersymmetry, there are
gravitational waves propagating on domain walls or on bubbles of nothing that
asymptote to AdS_4. Furthermore, we obtain the additional constraints obeyed by
half-supersymmetric vacua. These are divided into four categories, that include
bubbles of nothing which are asymptotically AdS_4, pp-waves on domain walls,
AdS_3 x R, and spacetimes conformal to AdS_3 times an interval.Comment: 55 pages, uses JHEP3.cls. v2: Minor errors corrected, small changes
in introductio
M-Horizons
We solve the Killing spinor equations and determine the near horizon
geometries of M-theory that preserve at least one supersymmetry. The M-horizon
spatial sections are 9-dimensional manifolds with a Spin(7) structure
restricted by geometric constraints which we give explicitly. We also provide
an alternative characterization of the solutions of the Killing spinor
equation, utilizing the compactness of the horizon section and the field
equations, by proving a Lichnerowicz type of theorem which implies that the
zero modes of a Dirac operator coupled to 4-form fluxes are Killing spinors. We
use this, and the maximum principle, to solve the field equations of the theory
for some special cases and present some examples.Comment: 36 pages, latex. Reference added, minor typos correcte
Superembeddings, Non-Linear Supersymmetry and 5-branes
We examine general properties of superembeddings, i.e., embeddings of
supermanifolds into supermanifolds. The connection between an embedding
procedure and the method of non-linearly realised supersymmetry is clarified,
and we demonstrate how the latter arises as a special case of the former. As an
illustration, the super-5-brane in 7 dimensions, containing a self-dual 3-form
world-volume field strength, is formulated in both languages, and provides an
example of a model where the embedding condition does not suffice to put the
theory on-shell.Comment: plain tex, 28 p
All the supersymmetric solutions of N=1,d=5 ungauged supergravity
We classify the supersymmetric solutions of ungauged N=1 d=5 SUGRA coupled to
vector multiplets and hypermultiplets. All the solutions can be seen as
deformations of solutions with frozen hyperscalars. We show explicitly how the
5-dimensional Reissner-Nordstrom black hole is deformed when hyperscalars are
living on SO(4,1)/SO(4) are turned on, reducing its supersymmetry from 1/2 to
1/8. We also describe in the timelike and null cases the solutions that have
one extra isometry and can be reduced to N=2,d=4 solutions. Our formulae allows
the uplifting of certain N=2,d=4 black holes to N=1,d=5 black holes on KK
monopoles or to pp-waves propagating along black strings.Comment: Some typos fixed and some paragraphs improved. 44 pages, Latex 2e
file, no figures. Version to be published in JHE
AdS4 flux vacua in type II superstrings and their domain-wall solutions
We investigate the emergence of supersymmetric negative-vacuum-energy ground
states in four dimensions. First, we rely on the analysis of the effective
superpotential, which depends on the background fluxes of the internal
manifold, or equivalently has its origin in the underlying gauged supergravity.
Four-dimensional, supersymmetric anti-de Sitter vacua with all moduli
stabilized appear when appropriate Ramond and Neveu--Schwarz fluxes are
introduced in IIA. Geometric fluxes are not necessary. Then the whole setup is
analyzed from the perspective of the sources, namely D/NS-branes or
Kaluza--Klein monopoles. Orientifold planes are also required for tadpole
cancellation. The solutions found in four dimensions correspond to domain walls
interpolating between AdS4 and flat spacetime. The various consistency
conditions (equations of motion, Bianchi identities and tadpole cancellation
conditions) are always satisfied, albeit with source terms. We also speculate
on the possibility of assigning (formal) entropies to AdS4 flux vacua via the
corresponding dual brane systems.Comment: Acknowledgment replace
Proper motions in the VVV Survey: Results for more than 15 million stars across NGC 6544
Context: In the last six years, the VVV survey mapped 562 sq. deg. across the
bulge and southern disk of the Galaxy. However, a detailed study of these
regions, which includes globular clusters (GCs) and thousands of open
clusters is by no means an easy challenge. High differential reddening and
severe crowding along the line of sight makes highly hamper to reliably
distinguish stars belonging to different populations and/or systems. Aims: The
aim of this study is to separate stars that likely belong to the Galactic GC
NGC 6544 from its surrounding field by means of proper motion (PM) techniques.
Methods: This work was based upon a new astrometric reduction method optimized
for images of the VVV survey. Results: Photometry over the six years baseline
of the survey allowed us to obtain a mean precision of mas/yr, in
each PM coordinate, for stars with Ks < 15 mag. In the area studied here,
cluster stars separate very well from field stars, down to the main sequence
turnoff and below, allowing us to derive for the first time the absolute PM of
NGC 6544. Isochrone fitting on the clean and differential reddening corrected
cluster color magnitude diagram yields an age of 11-13 Gyr, and
metallicity [Fe/H] = -1.5 dex, in agreement with previous studies restricted to
the cluster core. We were able to derive the cluster orbit assuming an
axisymmetric model of the Galaxy and conclude that NGC 6544 is likely a halo
GC. We have not detected tidal tail signatures associated to the cluster, but a
remarkable elongation in the galactic center direction has been found. The
precision achieved in the PM determination also allows us to separate bulge
stars from foreground disk stars, enabling the kinematical selection of bona
fide bulge stars across the whole survey area. Our results show that VVV data
is perfectly suitable for this kind of analysis.Comment: 13 pages, 12 figures, accepted in A&
Three-dimensional N=8 conformal supergravity and its coupling to BLG M2-branes
This paper is concerned with the problem of coupling the N=8 superconformal
Bagger-Lambert-Gustavsson (BLG) theory to N=8 conformal supergravity in three
dimensions. We start by constructing the on-shell N=8 conformal supergravity in
three dimensions consisting of a Chern-Simons type term for each of the gauge
fields: the spin connection, the SO(8) R-symmetry gauge field and the spin 3/2
Rarita-Schwinger (gravitino) field. We then proceed to couple this theory to
the BLG theory. The final theory should have the same physical content, i.e.,
degrees of freedom, as the ordinary BLG theory. We discuss briefly the
properties of this "topologically gauged" BLG theory and why this theory may be
useful.Comment: 20 pages, v2: references and comments added, presentation in section
3.2 extended. v3: misprints and a sign error corrected, version published in
JHE
A Three-Dimensional Code for Muon Propagation through the Rock: MUSIC
We present a new three-dimensional Monte-Carlo code MUSIC (MUon SImulation
Code) for muon propagation through the rock. All processes of muon interaction
with matter with high energy loss (including the knock-on electron production)
are treated as stochastic processes. The angular deviation and lateral
displacement of muons due to multiple scattering, as well as bremsstrahlung,
pair production and inelastic scattering are taken into account. The code has
been applied to obtain the energy distribution and angular and lateral
deviations of single muons at different depths underground. The muon
multiplicity distributions obtained with MUSIC and CORSIKA (Extensive Air
Shower simulation code) are also presented. We discuss the systematic
uncertainties of the results due to different muon bremsstrahlung
cross-sections.Comment: 24 pages, 11 Postscript figures, LaTeX, to be published in
Astroparticle Physic
- …
