Black holes and
"remnants" at the LHC
Benjamin Koch FIGSS/University of Frankfurt
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• What are Large eXtra Dimensions and Motivation
• Observables for LXDs
• Black holes in 4+d dimensions
• Production and decay of black holes in 4+d dimensions
• Results
• Outlook
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Models with LXDs
Main motivation hierachy problem: Why is gravitation so weak?
String theory suggests XDs but it is hard to make predictions
Effective theories with LXDs:
• Arkani-Hamed, Dimopoulos & Dvali (ADD)
• Randall & Sundrum (RS)
• Universal Extra Dimensions (UXD)
All contain one or more eXtra dimensions that are compactified on a radius
that is so small that it could not be observed up to now.
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The ADD model
• 3+d space like dimensions
• d dimensions on d-torus with radii R
• only gravity propagates in all dimensions (bulk)
• all other in 4-dim. space time (brane)
Newton with LXDs:
N. Arkani-Hamed, S. Dimopoulos and G. R. Dvali, Phys. Lett. B 429, 263 (1998);
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Observables of LXDs
MeV region
supernova and
neutronstar cooling
400 TeV ultra high
energetic cosmic rays
CM Energy/n
Newtons law
TeV region todays
More than 1 XD
Strongest constraints
Newton checked to m on R for all d
14 TeV Large
Hadron Collider LHC
Possible observables
- microscopic black holes
- graviton productionmodified cross sections
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Black holes in 4+d dimensions
- XD black hole in
-Topology of the
- XD black hole in
-Topology of the
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Vital discussion
- S. Dimopoulos and G. Landsberg Phys. Rev. Lett. 87, 161602 (2001).
- M. B. Voloshin, Phys. Lett. B 518, 137 (2001); Phys. Lett. B 524, 376 (2002).
- S. B. Giddings, ed. N. Graf, eConf C010630, P328 (2001).
- S. N. Solodukhin, Phys. Lett. B 533, 153 (2002).
- H. Yoshino and V. S. Rychkov, Phys. Rev. D 71 (2005) 104028 ...
Konsens finally...
most confirm geometrical
estimate of cross section;
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- "Balding phase":BH gets rid of its hair
mainly via gravitational radiation ->not visible in detector
- Hawking phase: decay
mainly into standard-model particles.
- R. Emparan, G. T. Horowitz and R. C. Myers Phys. Rev. Lett. 85, 499 (2000)
- S. B. Giddings and S. Thomas, Phys. Rev. D 65 056010 (2002).
- C. M. Harris, M. J. Palmer, M. A. Parker, P. Richardson, A. Sabetfakhri and B. R.
Webber, [arXiv:hep-ph/0411022]...
- Final state: Two possible scenarios
- Hawking radiation continues until MBH....Mf and then
performes something like a final decay
- Rapid decay slows down to form quasistable remnant
- Y. B. Zel’dovich, in: ”Proc. 2nd Seminar in Quantum Gravity”, edited by M. A. Markov
and P. C. West, Plenum, New York (1984).
- R. J. Adler, P. Chen and D. I. Santiago, Gen. Rel. Grav. 33, 2101 (2001)
- J. D. Barrow, E. J. Copeland and A. R. Liddle, Phys. Rev. D 46, 645 (1992).
- S. Coleman, J. Preskill and F. Wilczek, Mod. Phys. Lett. A6 1631 (1991).
- S. Hossenfelder, M. Bleicher, S. Hofmann, H. Stocker and A. Kotwal, Phys. Lett. B 566, 233
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Modified decay in the presence
of quasistable black hole
Corrections to the standard hawking evaporations
should are presumable suppressed by factors of Mf/MBH
therefore the entropy of a micro-black hole can be written as
In the micro canonical picture the Mass evotution is given by
This gives in the limit M>>MR the macro canonical Hawking rate
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Mass evolution
Black hole for
Mf=MR=1 TeV
These spectra were incorporated into an event generator(based on Pythia)
and the results were compared to an event generator without quasi stable
black holes: "charybdis"
C. M. Harris, P. Richardson and B. R. Webber, JHEP 0308, 033 (2003) [arXiv:hep-ph/0307305]
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Quasi-stable black holes distinguishable from complete BH decay:
B.Koch, M.Bleicher and S.Hossenfelder, ``Black hole remnants at the LHC,'' JHEP 0510 (2005) 053
But how can we tell that it was a BH at all?
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- A charged remnant could
be seen in the detector directely
S.Hossenfelder, B.Koch and M.Bleicher,
``Trapping black hole remnants,'' arXiv:hep-ph/0507140.
- A completely decaying BH
requests carefull triggering
and selection of observables:
T. Humanic, "Extra-dimensional
physics with p+p in the ALICE Experiment"
Alice-Internal note- (preliminary)
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- In LXD scenarios a large number of microsc black holes
will be produced at the LHC
- A final decay or a quasi stable black hole
should be distinguishable by just
observing the decay products!
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- Closer look at possible observables
and comparison to other beyond
the standard model scenarios
- Looking forward to LHC data
thanks to
Marcus Bleicher,
Sabine Hossenfelder,
Horst Stoecker,
Tom Humanic,
Ulrich Harbach
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Black holes and