47 research outputs found
Discovering New Physics in the Decays of Black Holes
If the scale of quantum gravity is near a TeV, the LHC will be producing one
black hole (BH) about every second, thus qualifying as a BH factory. With the
Hawking temperature of a few hundred GeV, these rapidly evaporating BHs may
produce new, undiscovered particles with masses ~100 GeV. The probability of
producing a heavy particle in the decay depends on its mass only weakly, in
contrast with the exponentially suppressed direct production. Furthemore, BH
decays with at least one prompt charged lepton or photon correspond to the
final states with low background. Using the Higgs boson as an example, we show
that it may be found at the LHC on the first day of its operation, even with
incomplete detectors.Comment: 4 pages, 3 figure
Quantum Gravity Effects in Black Holes at the LHC
We study possible back-reaction and quantum gravity effects in the
evaporation of black holes which could be produced at the LHC through a
modification of the Hawking emission. The corrections are phenomenologically
taken into account by employing a modified relation between the black hole mass
and temperature. The usual assumption that black holes explode around TeV
is also released, and the evaporation process is extended to (possibly much)
smaller final masses. We show that these effects could be observable for black
holes produced with a relatively large mass and should therefore be taken into
account when simulating micro-black hole events for the experiments planned at
the LHC.Comment: 14 pages, 8 figures, extended version of hep-ph/0601243 with new
analysis of final products, final version accepted for publication in J.
Phys.
Black Holes at Future Colliders and Beyond: a Topical Review
One of the most dramatic consequences of low-scale (~1 TeV) quantum gravity
in models with large or warped extra dimension(s) is copious production of mini
black holes at future colliders and in ultra-high-energy cosmic ray collisions.
Hawking radiation of these black holes is expected to be constrained mainly to
our three-dimensional world and results in rich phenomenology. In this topical
review we discuss the current status of astrophysical observations of black
holes and selected aspects of mini black hole phenomenology, such as production
at colliders and in cosmic rays, black hole decay properties, Hawking radiation
as a sensitive probe of the dimensionality of extra space, as well as an
exciting possibility of finding new physics in the decays of black holes.Comment: 31 pages, 10 figures To appear in the Journal of Physics
Black Hole Chromosphere at the LHC
If the scale of quantum gravity is near a TeV, black holes will be copiously
produced at the LHC. In this work we study the main properties of the light
descendants of these black holes. We show that the emitted partons are closely
spaced outside the horizon, and hence they do not fragment into hadrons in
vacuum but more likely into a kind of quark-gluon plasma. Consequently, the
thermal emission occurs far from the horizon, at a temperature characteristic
of the QCD scale. We analyze the energy spectrum of the particles emerging from
the "chromosphere", and find that the hard hadronic jets are almost entirely
suppressed. They are replaced by an isotropic distribution of soft photons and
hadrons, with hundreds of particles in the GeV range. This provides a new
distinctive signature for black hole events at LHC.Comment: Incorporates changes made for the version to be published in Phys.
Rev. D. Additional details provided on the effect of the chromosphere in
cosmic ray shower
Large extra dimension effects in Higgs boson production at linear colliders and Higgs factories
In the framework of quantum gravity propagating in large extra dimensions,
the effects of virtual Kaluza-Klein graviton and graviscalar interference with
Higgs boson production amplitudes are computed at linear colliders and Higgs
factories. The interference of the almost-continuous spectrum of the KK
gravitons with the standard model resonant amplitude is finite and predictable
in terms of the fundamental D-dimensional Plank scale M_D and the number of
extra dimensions \delta. We find that, for M_D ~ 1 TeV and \delta=2, effects of
the order of a few percent could be detected for heavy Higgs bosons (m_H>500
GeV) in Higgs production both via WW fusion in e^+e^- colliders and at
\mu^+\mu^- Higgs-boson factories.Comment: 16 pages, 2 figures ; a few comments and references added ; version
to appear in JHE
Minimum length effects in black hole physics
We review the main consequences of the possible existence of a minimum
measurable length, of the order of the Planck scale, on quantum effects
occurring in black hole physics. In particular, we focus on the ensuing minimum
mass for black holes and how modified dispersion relations affect the Hawking
decay, both in four space-time dimensions and in models with extra spatial
dimensions. In the latter case, we briefly discuss possible phenomenological
signatures.Comment: 29 pages, 12 figures. To be published in "Quantum Aspects of Black
Holes", ed. X. Calmet (Springer, 2014
The Beyond the Standard Model Working Group: Summary Report
Report of the "Beyond the Standard Model" working group for the Workshop `Physics at TeV Colliders', Les Houches, France, 21 May - 1 June 2001. It consists of 18 separate parts: 1. Preface; 2. Theoretical Discussion; 3. Numerical Calculation of the mSUGRA and Higgs Spectrum; 4. Theoretical Uncertainties in Sparticle Mass Predictions; 5. High Mass Supersymmetry with High Energy Hadron Colliders; 6. SUSY with Heavy Scalars at LHC; 7. Inclusive Study of MSSM in CMS; 8. Establishing a No-Lose Theorem for NMSSM Higgs Boson Discovery at the LHC; 9. Effects of Supersymmetric Phases on Higgs Production in Association with Squark Pairs in the Minimal Supersymmetric Standard Model; 10. Study of the Lepton Flavour Violating Decays of Charged Fermions in SUSY GUTs; 11. Interactions of the Goldstino Supermultiplet with Standard Model Fields; 12. Attempts at Explaining the NuTeV Observation of Di-Muon Events; 13. Kaluza-Klein States of the Standard Model Gauge Bosons: Constraints From High Energy Experiments; 14. Kaluza-Klein Excitations of Gauge Bosons in the ATLAS Detector; 15. Search for the Randall Sundrum Radion Using the ATLAS Detector; 16. Radion Mixing Effects on the Properties of the Standard Model Higgs Boson; 17. Probing Universal Extra Dimensions at Present and Future Colliders; 18. Black Hole Production at Future Colliders.Report of the Beyond the Standard Model working group for the Workshop `Physics at TeV Colliders', Les Houches, France, 21 May - 1 June 2001. It consists of 18 separate parts: 1. Preface: 2. Theoretical Discussion: 3. Numerical Calculation of the mSUGRA and Higgs Spectrum: 4. Theoretical Uncertainties in Sparticle Mass Predictions: 5. High Mass Supersymmetry with High Energy Hadron Colliders: 6. SUSY with Heavy Scalars at LHC: 7. Inclusive Study of MSSM in CMS: 8. Establishing a No-Lose Theorem for NMSSM Higgs Boson Discovery at the LHC: 9. Effects of Supersymmetric Phases on Higgs Production in Association with Squark Pairs in the Minimal Supersymmetric Standard Model: 10. Study of the Lepton Flavour Violating Decays of Charged Fermions in SUSY GUTs: 11. Interactions of the Goldstino Supermultiplet with Standard Model Fields: 12. Attempts at Explaining the NuTeV Observation of Di-Muon Events: 13. Kaluza-Klein States of the Standard Model Gauge Bosons: Constraints From High Energy Experiments: 14. Kaluza-Klein Excitations of Gauge Bosons in the ATLAS Detector: 15. Search for the Randall Sundrum Radion Using the ATLAS Detector: 16. Radion Mixing Effects on the Properties of the Standard Model Higgs Boson: 17. Probing Universal Extra Dimensions at Present and Future Colliders: 18. Black Hole Production at Future Colliders
Critical Trapped Surfaces Formation in the Collision of Ultrarelativistic Charges in (A)dS
We study the formation of marginally trapped surfaces in the head-on
collision of two ultrarelativistic charges in space-time. The metric of
ultrarelativistic charged particles in is obtained by boosting
Reissner-Nordstr\"om space-time to the speed of light. We show that
formation of trapped surfaces on the past light cone is only possible when
charge is below certain critical - situation similar to the collision of two
ultrarelativistic charges in Minkowski space-time. This critical value depends
on the energy of colliding particles and the value of a cosmological constant.
There is richer structure of critical domains in case. In this case
already for chargeless particles there is a critical value of the cosmological
constant only below which trapped surfaces formation is possible. Appearance of
arbitrary small nonzero charge significantly changes the physical picture.
Critical effect which has been observed in the neutral case does not take place
more. If the value of the charge is not very large solution to the equation on
trapped surface exists for any values of cosmological radius and energy density
of shock waves. Increasing of the charge leads to decrease of the trapped
surface area, and at some critical point the formation of trapped surfaces of
the type mentioned above becomes impossible.Comment: 30 pages, Latex, 7 figures, Refs. added and typos correcte
A Quasi-Model-Independent Search for New Physics at Large Transverse Momentum
We apply a quasi-model-independent strategy ("Sleuth") to search for new high
p_T physics in approximately 100 pb^-1 of ppbar collisions at sqrt(s) = 1.8 TeV
collected by the DZero experiment during 1992-1996 at the Fermilab Tevatron.
Over thirty-two e mu X, W+jets-like, Z+jets-like, and 3(lepton/photon)X
exclusive final states are systematically analyzed for hints of physics beyond
the standard model. Simultaneous sensitivity to a variety of models predicting
new phenomena at the electroweak scale is demonstrated by testing the method on
a particular signature in each set of final states. No evidence of new high p_T
physics is observed in the course of this search, and we find that 89% of an
ensemble of hypothetical similar experimental runs would have produced a final
state with a candidate signal more interesting than the most interesting
observed in these data.Comment: 28 pages, 17 figures. Submitted to Physical Review
Black Hole Remnants at the LHC
We investigate possible signatures of black hole events at the LHC in the
hypothesis that such objects will not evaporate completely, but leave a stable
remnant. For the purpose of defining a reference scenario, we have employed the
publicly available Monte Carlo generator CHARYBDIS2, in which the remnant's
behavior is mostly determined by kinematic constraints and conservation of some
quantum numbers, such as the baryon charge. Our findings show that electrically
neutral remnants are highly favored and a significantly larger amount of
missing transverse momentum is to be expected with respect to the case of
complete decay.Comment: LaTeX, 13 pages, 2 tables, 5 figures, references added and typos
corrected. To appear in EPJ