CGC Friday Seminar

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CGC Friday Seminar
October 13, 2006
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HUNTING BLACK HOLES AT THE LHC
Luis Anchordoqui University of Wisconsin-Milwaukee
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OUTLINE
INTRODUCTION
BH PRODUCTION EVAPORATION
QUARK GLUON PLASMA
LHC DISCOVERY REACH
CONCLUSIONS
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INTRODUCTION
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Thorne Hoop Conjecture
Horizons form M compacted into a
region whose circunference in every direction lt 2
p r
s
BH
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12
Mass 10 kg
Mass 10 kg
-15
Radius 20 km
Radius 10 m
-8
19
-35
Lightest black holes Mass 10 kg
10 GeV Radius 10 m
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3
97
3
Highest density 10 kg/m
Highest density 10 kg/m
- 6
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Temperature 10 K
Temperature 10 K
67
10
Evaporation time 10 yr
Evaporation time 10 yr
Given currently accessible energies lt 2 TeV
Study of such black holes far beyond realm of
experimental particle physics
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Spacetimes unseen dimensions
Hypothesis Universe has D 4 n dimensions
SM physics
Sub-millimeter extra dimmensions
2 rc
Gravity only

• SM lives in 4 dimensions
• Gravity spills into internal dimensions

Arkani Hamed-Dimopoulos-Dvali PLB429 (1998) 263
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TeV Scale Gravity
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Black hole production in particle collisions
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Probes of TeV Scale Gravity
? Tests of Newtons law on sub- millimeter scale
Hoyle Schmidt Heckel Adelberger
Gundlach Kapner Swanson PRL 86 (2001) 1418 ?
Bounds from supernova cooling and neutron star
heating Hannestad Raffelt PRL 87 (2002)
071301 ? Searches for sub-Planckian signals at
the Tevatron D0 Collaboration PRL 86 (2001)
1156 ? Absence ? - showers mediated by BH
LAA Goldberg Feng Shapere PRD 68 (2003)
104025
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Orders of magnitude
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Schwarzschild phase
Planck phase
Balding phase
Spin-down phase
Birth
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Time Scales
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(No Transcript)
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Large Hadron Collider
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BH PRODUCTION EVAPORATION
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parton parton cross section
proton proton cross section
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Inelasticity
Spheroid Prolate Horizons
Classical gravitational radiation
Strong dependence with b
Yoshino - Nambu, PRD 67 (2003) 024009
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Homework
Design a detector with sensitivity to these
gravitational waves
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f gt 100 YHz 10 Hz
YES !
One hundred yottahertz !!!
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Event Rates
Inelasticity included (solid) neglected
(dashed)
LAA- Feng Goldberg Shapere PLB 594 (2004) 363
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Black Hole Evaporation

• Hawking Temperature

• Hawking Wavelength

gt BH size

• BH point radiator emits mostly s- waves

• Decays with equal probability on 3- brane/bulk

• Many more particles on 3-brane

Black Hole
3 brane
Emparan-Horowitz-Myers PRL 85 (2000)
499 Dimopoulos-Landsberg PRL 87 (2001) 161602
BH decays visibly to SM fields
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Thermal Spectrum
greybody absorption area
particle - spin
Average total emission rate
number of internal degrees of freedom
for bosons (fermions)
Instantaneous Schwarzschild radius
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Thermal Spectrum
greybody absorption area
particle - spin
Rate of change of BH mass

for bosons (fermions)
number of internal degrees of freedom
Instantaneous Schwarzschild radius
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Average multiplicity
Initial entropy
BH lifetime

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Quantitative measures of the validity of the
semiclassical analysis
Initial entropy large enough to ensure
well-defined thermodynamic description
BHs lifetime large compared to its inverse mass
to ensure it behaves like well-defined resonance
BHs mass large compared to scale of the 3-brane
tension to ensure brane does not perturb BH metric

All the criteria are satisfied for

LAA- Feng Goldberg Shapere PLB 594 (2004) 363
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Stringballs
STRING BH
correspondence principle
adiabatic transition to massive superstring mode
Horowitz, Polchinski, PRD 55 (1997) 6189 Damour,
Veneziano, NPB 568 (2000) 93
Energy radiation continues at unchanging
Hagedorn temperature
Amati, Russo, PLB 454 (1999) 207
Continuity in cross section at correspondence
point
(at least parametrically in energy and
string coupling)
provides independent supportive argument
Dimopoulos, Emparan, PLB 526 (2002) 393
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Stringballs
LAA, Feng, Goldberg, Shapere, COSMO 03 (hep-ph/
0309082)
can be though off as lower limit on as
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QUARK GLUON PLASMA
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Quark gluon plasma?
BH evaporation creates radiation shell
propagating outward at the speed of light
Radius
Thickness
After end of evaporation shell has radius
and thickness
Interaction rate for quarks and anti-quarks
cross section for gluon bremsstrahlung
effective density
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Quark gluon plasma?
Dominant diagram of gluon bremsstrahlung at low
momentum transfer
QCD coupling constant
Infared cutoff related to the off-shell momentum
of the exchanged gluon
Exchanged (virtual) gluon travels at most
distance during intaraction
Uncertainty principle
lower bound on the momentum transfer
At any time has a maximum value
corresponding to
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Quark gluon plasma?
BH evaporation creates radiation shell
propagating outward at the speed of light
Radius
Thickness
After end of evaporation shell has radius
and thickness
Interaction rate for quarks and anti-quarks
cross section for gluon bremsstrahlung
effective density
LAA, Goldberg PRD 67 (2003) 064010
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Quark gluon plasma?
Interaction rate for quarks and anti-quarks
For
To remain pertubative
cumulative number of interactions/quark for
down to some value
Taking
For
30 interactions per quark
LAA, Goldberg PRD 67 (2003) 064010
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Soft photon spectrum
Quark gluon spectrum of the outer surface of the
thermal cromosphere
Pothon spectrum
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Soft photon spectrum
LAA-Goldberg PRD 67 (2003) 064010
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Mean lifetime of the chromosphere
Full width at half maximum (max) of
distribution
Spectrum peaks at
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HINTS FROM COSMIC RAYS
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Black Holes from Cosmic Rays
Cosmic ray collisions in upper atmosphere
dominates by 5 orders
of magnitude
BH production by hadronic cosmic rays unobservable
orders of magnitude larger than SM but much less
than hadronic
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North
AMANDA
South Pole
Dome
road to work
Summer camp
1500 m
Amundsen-Scott South Pole station
2000 m
not to scale
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DOWN GOING EVENTS
UP GOING EVENTS
New physics beyond the electroweak scale can
distort the relative numbers of down and up
neutrinos detected
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DOWN GOING EVENTS
UP GOING EVENTS
Increases event rates
Increases event rates
At relevant energies neutrino interaction
length satisfies
Rate suppressed
Increases event rates
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PROBING NEUTRINO- NUCLEON CROSS SECTION

Neutrino lab energy

AMANDA Collaboration, Astropart. Phys. 22 (2005)
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In full generality
bound on flux x probability of
interaction (cross section)
LAA, Feng Goldberg Phys. Rev. Lett. 96 (2006)
021101
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PROBING NEUTRINO- NUCLEON CROSS SECTION

LAA, Feng Goldberg Phys. Rev. Lett. 96 (2006)
021101
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PROBING NEUTRINO- NUCLEON CROSS SECTION
UP- GOING EVENTS
DOWN GOING EVENTS

LAA, Feng Goldberg Phys. Rev. Lett. 96 (2006)
021101
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IceCube integrated
luminosity _at_

Waxman Bahcall Phys. Rev. D 59 (1999)
023002 Ahlers, LAA, Goldberg, Halzen, Ringwald,
Weiler, Phys. Rev. D 72 (2005) 023001
Stecker, Done, Salamon Sommers,
Phys. Rev. Lett. 69 (1992) 2738 Neronov, Semikoz,
Aharonian Kalashev, Phys. Rev. Lett. 89 (2002)
051101
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LHC DISCOVERY REACH
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BH SIGNAL
Events with total multiplicity and at
least one with energy gt 100 GeV
Dimopoulos-Landsberg PRL 87 (2001) 161602
Average multiplicity for any subset of states s
Branching fraction

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BH SIGNAL
Probability of and
Probability of and

Signal
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SM background dominated by jets
and jets
Background rates estimated using
PYTHIA Dimopoulos-Landsberg PRL 87 (2001) 161602
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Discovery reach
LAA-Feng-Goldberg-Shapere PLB 594 (2004) 363
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BH chromosphere at the LHC ?
Branching fraction to quarks/antiquarks is about
60

• For final states with 10 quarks/antiquarks the
  emitted partons are closely spaced outside the
  horizon

• Partons do not fragment into hadrons in vacuum
  but more likely into a kind of quark-gluon plasma

The requisite multiplicity will materialize at
large M gt 3 M

• Thermal emission occurs far from the horizon at
  temperature characteristic of QCD scale

gt
D
BH
EXAMPLE

• Hundreds of soft photons and charged pions can
  serve as an additional marker for discovery

For M 1.2 TeV and M 6 TeV
Poisson probability for
0.06 Leads to about 6
chromosphere events per 100 fb
BH
D
LAA-Goldberg PRD 67 (2003) 064010
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Monte Carlo simulations
Black hole production and decay CHARYBDIS
event generator
Harris, Richardson, Webber, JHEP 0308 (2003) 033
Parton evolution and hadronization HERWIG
and PYTHIA
Black Hole Event Display
CHARYBDIS output using ATLAS ATLANTIS program
http//atlantis.web.cern.ch/atlantis
BH mass 8 TeV - 9 quarks 1 gluon 1 electron
1 positron 3 neutrinos
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CONCLUSIONS
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If TeV scale gravity is realized in Nature

• First hints of BH production may come soon
  
  from cosmic ray observations

• LHC would become a BH factory
  with
  an event rate of up to 1 BH per s

• Perhaps as early as 2010 we may all witness
  the birth
  of experimental quantum gravity

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If TeV scale gravity is realized in Nature

• LHC would become a BH factory
  
  with an event rate of up to 1 BH per second

• BHs can also be produced by cosmic rays

(Stay tuned for Matthews seminar)

• Perhaps as early as 2010 we may all witness
  the birth
  of experimental quantum gravity

LAA Glenz- Parker, work in progress
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Cross section for absorption
Accreation rate
EPILOGUE
Gluon energy density
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HUNTING SEASON
opens
DECEMBER 2007
THANKS QUESTIONS
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ANGULAR DISTRIBUTION
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AMANDA Energy distribution
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Brookhaven National Laboratory
February 2006
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New physics beyond the electroweak scale can
distort the relative numbers of down and up
neutrinos detected