Black Holes at Accelerators: Problems and Perspectives Savina - - PowerPoint PPT Presentation

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Black Holes at Accelerators: Problems and Perspectives

Savina Maria, JINR, Dubna

International Workshop "Bogoliubov readings", Dubna, 22 September 2010

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Black Hole formation in TeV Black Hole formation in TeV-

• scale gravity

scale gravity

Pictures by Sabine Hossenfelder

In large extra dimension models

• Gravity stronger at small distances
• Horizon radius larger
• For M ~ TeV it increases from 10-38 fm to 10-4 fm

For these BH Rh<< R and they have approximately higher dimensional spherical symmetry At the LHC partons can come closer than their Schwarzschild horizon

black hole production

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Evolution stages for BH

II-III. Hawking radiation phases (short spindown +

more longer Schwarzschild)

Quantum-mechanical decay trough tunneling, transition from Kerr spinning BH to stationary Schwarzschild one. angular momentum shedding (up to ~ 50% mass loss).

Corrections with Gray Body Factors

After this – thermal decay to all SM particles with black body energy spectra. Accelerating decay with a varying growing temperature. No flavor dependence, only number

• f D.o.f.– “democratic” decay
• IV. Planck phase: final explosion (subj for QGr)

BH remnant (non-detectable energy losses), N-body decay, Q, B, color are conserved or not conserved

• I. Balding phase

Asymmetric production, but “No hair” theorem: BH sheds its high multipole moments for fields (graviton and GB emitting classically), as electric charge and color. Characteristic time is about t ~ RS Result: BH are classically stable objects

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5 5

BH production in pp collisions: some well BH production in pp collisions: some well-

• known formulas

known formulas

Schwarzschild raduis of a

multidimensional BH

(R.C. Myers and M.J. Perry, Ann. Phys. 172, 304, 1986)

BH production cross section

(S. Dimopoulos, G. Landsberg, Phys.Rev.Lett.87:161602, 2001 hep-ph/0106295v1)

PDF’s

1 1 BH

2 2 3 ( 8 1

+

⎥ ⎥ ⎥ ⎦ ⎤ ⎢ ⎢ ⎢ ⎣ ⎡ ⎟ ⎟ ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎜ ⎜ ⎝ ⎛ + + Γ =

n S

n n M M M R π

∑ ∫

⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛ =

b a a b s M a a a a

sx M f x f x dx s M dM dL

, 2 BH 1 BH BH

2 BH

) ( 2

2 BH

ˆ BH BH BH

) BH ( ˆ

M s

ab dM dL dM d

=

→ = σ σ

2 S

R π

3 1 1 S

) ( ~

− − D D D

M E M R

n D + = 4 ,

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BH Production in pp collisions at the LHC BH Production in pp collisions at the LHC

Increasing cross section, no suppression from small couplings

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Hawking evaporation of BH Hawking evaporation of BH

Hawking temperature

(R.C. Myers and M.J. Perry,

• Ann. Phys. 172, 304, 1986)

where

Multiplicity of produced particles in BH decay

S n BH H

R n n n n M M M T π π 4 1 4 1 2 3 8 2

1 1

+ = + × ⎟ ⎟ ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎜ ⎜ ⎝ ⎛ ⎟ ⎠ ⎞ ⎜ ⎝ ⎛ + Γ + =

+ H x x H

T a c e x dx c e x x dx T E = ± ± =

∫ ∫

∞ ∞ 2 2

1 1 1

E M N

BH

=

H

T E x =

Planckian spectrum (black body)

1 1 1 2 BH

2 2 3 8 1 2

+ + +

⎟ ⎟ ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎜ ⎜ ⎝ ⎛ + ⎟ ⎠ ⎞ ⎜ ⎝ ⎛ + Γ ⎟ ⎠ ⎞ ⎜ ⎝ ⎛ + =

n n n

n n M M n N π

) 3 ( 1 H − −

∝

D

M T

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Grey Body Factors for BH Decay Grey Body Factors for BH Decay

∑ ∑

+ =

−

m l m l m l m l W

dt d dN dt d dN dt d dN

, , , , , , 1

2 ω ω ω

1 ] exp[ 2 1

H , , , ,

m T dt d dN

m l s m l s

ω ω Γ =

Grey body factors # D.o.F. for e- # D.o.F. for GB

∑

=

−

m l m l e

dt d dN dt d dN

, , , 2 1

2 ω ω

h

r n T π 4 1

H

+ =

Papers on GBF:

• P. Kanti, J. March-Russell, I. Olasagasti K. Tamvakis, 2002;
• G. Duffy, C. Harris, P. Kanti and E. Winstanley, 2005;
• M. Casals, P. Kanti and E. Winstanley, S. R. Dolan, 2006-2007
• D. Ida, K.-y. Oda and S. C. Park, 2003-2006

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BH production in pp collisions at the LHC BH production in pp collisions at the LHC

DL ‘01 For the LHC energies: a) Parton-level production cross section b) Differential cross section c) Hawking temperature d) Average decay multiplicity for Schwarzschild BH n=4

(S. Dimopoulos, G. Landsberg, Phys.Rev.Lett.87:161602, 2001, hep-ph/0106295v1)

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Entropy, BH decay and Entropy, BH decay and M Mmin

min(BH

(BH) )

BH Entropy Democratic decay blinded to flavor: probabilities are the same for all species (violation of some conservation laws) SBH must be large enough to reproduce thermal BH decay

1 1 2 3 1 2 BH BH

2 2 3 2 2 4

+ − + +

⎟ ⎟ ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎜ ⎜ ⎝ ⎛ + ⎟ ⎠ ⎞ ⎜ ⎝ ⎛ + Γ ⎟ ⎠ ⎞ ⎜ ⎝ ⎛ + =

n n n n n

n n M M n S π π

(R.C. Myers and M.J. Perry,

• Ann. Phys. 172, 304, 1986)

(S.B. Giddings, hep-ph/0110127v3,

• K. Cheung, Phys. Rev. Lett. 88, 221602,

2002)

25 1 1

BH BH

> ⇒ << S S

• K. Cheung, PR D66, 036007 (2002).

M M 5

min BH ≥

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# # D.o.f D.o.f. counting and . counting and “ “democracy democracy” ” of decay

• f decay

4 3 4 2 1

color flavor

t b c s d u

3 4 6

, , , , ,

↓ ↓ × ×

12 12 12 12 12 12 2 2 2 4 4 4 1 16 2 6 3 , , , , , ; , , , , , ; , , , , ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓

± ± ± ±

t b c s d u e H g W Z

e τ µ ν

ν ν τ µ γ

The ratio of hadronic/leptonic is 5 : 1

(Gauge+Higgs) : (Leptons) : (Quarks) = 28 : 18 : 72

2 1 ; 2 1 2 − +

±

l

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Black Hole or String Ball? Black Hole or String Ball?

MBH >> MD : semiclassical well-known description for BH’s. What happens when MBH approach MD? BH becomes “stringy”, their properties become complex.

2 min s s BH

g M M =

2 2

) ( ) (

s s BH s s SB

g M M g M M

BH SB

= =

= σ σ

Matching:

Picture by Kingman Cheung

• S. Dimopoulos and R. Emparan, Phys. Lett. B526, 393 (2002), hep-ph/0108060

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Production cross section for BH, SB and p Production cross section for BH, SB and p-

• brane

brane

• K. Cheung, PR D66, 036007 (2002), hep-ph/0305003

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Final state of the SM process Final state of the SM process vs vs typical BH decay typical BH decay spectra spectra

Multi-jet and hard leptons events, spherical, typical temperature about 200 GeV

Pictures by Sabine Hossenfelder

SM BH decay

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BH Experimental Signatures BH Experimental Signatures

• Potentially large cross sections, approaching 103 fm or more
• An increase of cross sections with energy, according to an absense of gauge

coupling suppression (will be hard to see at the LHC)

• Relatively high sphericity for final states
• High multiplicity as proportional to the BH entropy of particles produced

(primaries)

• Hard trasverse leptons and jets, in significant numbers
• Approximately thermally determined ratios of species (democratic decay)
• Suppression of highest-energy jets
• Decrease of decay primary (lepton/parton) energy with total event transverse

energy (resulting from decreasing Hawking temperature with mass)

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Part II. Optimism Is fading Part II. Optimism Is fading… …

BH not as spectacular as advertized!!

• BH Production near the threshold and careful counting
• Conventions on a fundamental mass
• Inelasticity for BH formation at the LHC and in the UHECR
• Minimal M for a sensible definition of a BH
• LHC unlikely to make classical BH with thermal decay spectra.

So, what can we see, then?

• Two-body final states and QG

… … but it is not the end of the story

but it is not the end of the story

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Conventions on a fundamental mass Conventions on a fundamental mass

D=6 D=10

DL p

M M 3 . 1 =

DL p

M M 9 . 2 =

At least three definitions: Just numerical coefficients But: there is essential difference between M about 1 TeV and 2 TeV for the LHC!

L g x d g x d G S

D D D

∫ ∫

− + ℜ − = 2 1 8 1 π

D D D P

G M π π 4 ) 2 (

4 2 − − = D D D D

G M π π 8 ) 2 (

4 2 − − =

D D

G M 1

2 DL = −

2 DL 5 6 2

2

− − − − = D D D D P

M M π

D D P

M M

2 1

2

−

=

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At what energy can we safely speak about At what energy can we safely speak about “ “true true” ” BH BH production? production?

Clearly E > MD. But how much large?

From the talk by Lisa Randall at String’2007

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Inelasticity in BH production and Inelasticity in BH production and X Xmin

min

What part of initial collision energy actually was trapped in BH formation process?

inelasticity (pp → BH + X) – function of n,b

( )

∑ ∫ ∫ ∫

× =

j i j i u s s y x pp

Q v u f Q v f M n us r n F v dv du zdz M d x s

M

, 1 2 1 ( 1 min

) , ( ) , ( ) , , ( ) ( 2 , , ,

2 2 ) min

π σ

M M x

BH min min =

s M y

BH

ˆ ≡

max

b b z =

; ;

• H. Yoshino and Y. Nambu, Phys. Rev. D 67, 024009 (2003), gr-qc/0209003;
• L. A. Anchordoqui, J.L. Feng, H. Goldberg, and A.D. Shapere, hep-ph/0311365
• H. Yoshino, V.S. Rychkov, Phys. Rev. D71, 104028 (2005), hep-th/0503171

S S S

5 , , ; 5 , , 7 , : ) ( 5 , , ; 5 , , 6 , : ) ( R b M R b E M II R b M R b E M I

S

> = < = > = < = fb II fb I 1000 8 , 1 : ) ( 100 8 , 1 : ) ( × = × = σ σ

TSM 1034

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• J. A. Frost, J. R. Gaunt, M. O.P. Sampaio, M. Casals, S. R. Dolan, M. A. Parker, and B. R. Webber,

arXiv:0904.0979

Mass loss during BH formation in different models

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Inelasticity by TSM and predictions for the LHC

L.A. Anchordoqui, J.L. Feng, H. Goldberg, A.D. Shapere, Phys.Lett. B594 (2004), hep-ph/0311365

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BH production in UHECR

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BH Production in UHECR BH Production in UHECR

n=1-7, 5 Yrs. Pierre-Auger Observatory n=6

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The discovery reaches for the LHC The discovery reaches for the LHC

This region tested by PAO 5 Years (not excluded hardly) n=6

L.A. Anchordoqui, J.L. Feng, H. Goldberg, A.D. Shapere, Phys.Lett. B594 (2004), hep-ph/0311365

PAO didn’t see BH pruduction in HAS. It means what PAO didn’t see the signal in HAS

• Suppression of ν fluxes

in ED B conservation in νp We need wait for the LHC!

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Simulation of BH production and decay: event generators

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CHARYBDIS 1.003 (August 2006)

C.M. Harris, P. Richardson and B.R. Webber “CHARYBDIS: A Black Hole Event Generator”, JHEP 0308:033, hep-ph/0307305, 2003

http://www.ippp.dur.ac.uk/montecarlo/leshouches/generators/charybdis/

CHARYBDIS2 (April 2009)

• J. A. Frost, J. R. Gaunt, M. O.P. Sampaio, M. Casals, S. R. Dolan, M. A. Parker, and B. R.

Webber, arXiv:0904.0979

http://projects.hepforge.org/charybdis2/

CATFISH 1.1 (October 2006),

• M. Cavaglia, R. Godang, L. Cremaldi and D. Summers, “CATFISH:

A Monte Carlo simulator for black holes at the LHC", arXiv: hep-ph/0609001

http://www.phy.olemiss.edu/GR/catfish/catfish-v1.01.docu.pdf

BlackMax (April 2008, the latest version – March 2010)

De-Chang Dai, G. Starkman, D. Stojkovic, C. Issever, E. Rizvi, J. Tseng “BlackMax: A black-hole event generator with rotation, recoil, split branes and brane tension”, Phys.Rev. D77:076007, 2008, arXiv:0711.3012v4

http://projects.hepforge.org/blackmax/

Black Hole Event Generators

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CHARYBDIS1 Gen.: Analysis and results for the CMS CHARYBDIS1 Gen.: Analysis and results for the CMS

M_rec Sphericity CMS PTDR Vol. II, 2007 Hard jets, leptons and γ’s L = 30 fb-1 As a benchmark: 2 TeV/c2 fundamental Planck scale 4 TeV/c2 – 14 TeV/c2 BH mass n=3 number of ED

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Total vs visible energy of decay products

Sqrt(s)=14 TeV, n=6, M=1 TeV, MBH=5 TeV Cut on eta: |η|<3 can be applied

• M. Savina, V. Konoplianikov ’2010

all

• nly

visible all

• nly

visible

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Invariant mass of decay products (visible only + kin. cuts + acceptance)

• M. Savina, V. Konoplianikov ’2010

BH gen BH gen + acc. invisible excl. invisible excl. + rec. Sqrt(s) = 14 TeV, n = 6, M =1 TeV, MBH = 5 TeV

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Invisible energy (from neutrinos and gravitons), in percents of total energy, Charybdis2

• M. Savina, V. Konoplianikov ’2010

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M = 1 TeV MBH > 5 TeV M = 2 TeV MBH > 10 TeV M = 1 TeV MBH > 10 TeV M = 1 TeV MBH > 7 TeV

Charybdis2: S&B Sphericity for different fundamental scales and Xmin

• M. Savina, V. Konoplianikov ’2010

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CatFish (red) vs Charybdis (blue)

• M. Savina, V. Konoplianikov ’2010

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Charybdis2: S12 vs minimal visible mass, for different M def.

• M. Savina, V. Konoplianikov ’2010

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Charybdis2: S12 vs Planck mass, for different M def.

• M. Savina, V. Konoplianikov ’2010

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Charybdis2: number of partons in BH events

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Resume (not hard and final, because too many calculations and theoretical

Investigation are waiting to be done in this field)

• Black Holes is not a such spectacular signature as commonly advertized

earlier (from the very first papers in 1998).

• Likely the LHC will not be able to observe classical thermal BH decays.
• Careful counting pushes the minimal value of BH mass to higher energies what

make observation of BH hopeless at the LHC (important moment: there are alternative point of views on this problem, not just one possible).

• In any case for TeV scale gravity near the threshold we will see

signatures of QG (if one of them are realized by Nature).

• We can’t calculate its and make quantitative prediction. But

these signatures can be distinguished from other possible new physics (by high transversality for final states).