Other Exotic Scenarios at the LHC Kamal Benslama
Other Exotic Scenarios at the LHC Kamal Benslama Columbia University On behalf of the ATLAS and CMS Collaborations May 23, 2006 Hadron Collider Symposium K. Benslama Hadron Collider Symposium 1
BSM Scenarios Extra Dimensions Additional dimensions New states at Te. V Scale SUSY New particles at Te. V scale Previous talk New Physics at Te. V Little Higgs SM embedded in larger group New particles at Te. V scale Scale to stabilize m. H q Other Scenarios of New Physics - Leptoquarks - Excited fermions - New gauge bosons K. Benslama Hadron Collider Symposium Technicolor New strong interactions break EW symmetry New particles at Te. V scale 2
BSM Physics: Real life… “deviation-from. SM” hunting by experimentalists, then “model hunting” by theorists. It is a real challenge! It’s a complicated environment K. Benslama Hadron Collider Symposium 3
Large Extra Dimensions ü Large extra dimensions (>> 1/Te. V) – ADD model (Arkani, Dimopoulos, Dvali) – SM particules on brane – Gravity propagates in bulk (Xtra Ds) • Hence new gravity scale MPL 2 ~ MD 2+ R • KK graviton excitations MD ~ Te. V for R < mm KK mode separation is very small: e. g. : MD = 1 Te. V, n = 2 R = 0. 08 mm R-1 = 2. 6 x 10 -3 e. V n = 4 R = 1600 fm R-1 = 120 ke. V → continuous spectrum → high density of states compensates low coupling (~1/MPl ) chance to observe effects at LHC K. Benslama Hadron Collider Symposium 4
ADD: Graviton Emission ü Process ATLAS 100 fb-1 ü Reach – g. G – G K. Benslama Hadron Collider Symposium 5
ADD: Virtual Graviton ü Final state – Use effective scale 10 fb-1 Ms ( diverges if 2) ü Observables – Excess in ll & – more central than SM K. Benslama M Mll n=3 pp gg h Hadron Collider Symposium ATLAS 6
Te. V-1 Extra Dimension • One extra dimension compactified on a S 1/Z 2 orbifold • radius of compactification small enough gauge bosons in the bulk • fermions localized on: • a fixed point (M 1 model): invariance under y -y • opposite fixed points (M 2 model): under y y + 2 R • Kaluza-Klein spectra for Z(k), W(k) : mk 2 = m 02 + k 2 MC 2 • for MC = 4 Te. V: m 1 = 4 Te. V, m 2 = 8 Te. V look for pp (1)/Z(1) l+l- on top of SM Drell-Yan K. Benslama Hadron Collider Symposium 7
Te. V-1: Direct (1)/Z (1) Look for resonances in ll spectrum ATLAS 4 Te. V M 2 M 1 SM Observation up to ~ 5. 8 Te. V with For 1 Te. V< m <2. 5 Te. V 100 fb-1 up to ~ 8 Te. V with 100 fb-1 K. Benslama Hadron Collider Symposium 8
Te. V-1: Asymmetry ü Look at Forward- Backward asymmetry ATLAS M 2 100 fb-1 G* Z’ M 1 100 fb-1 K. Benslama Hadron Collider Symposium 9
Randall-Sundrum ü Motivation – 2 branes (Te. V & Planck ) connected by 1 warped ED – Coupling of KK states ~ 1/ – Graviton excitations – Constraints K. Benslama 0. 01 < k/Mpl < 0. 1 Hadron Collider Symposium 10
RS: Graviton Resonance CMS ~1. 3 Te. V CMS K. Benslama Hadron Collider Symposium 11
RS: Graviton Spin ü Look at angular distribution ATLAS 90% exclusion of spin-1 for m. G < 1. 7 Te. V K. Benslama Hadron Collider Symposium 12
Little Higgs: Heavy T L = 3· 105 pb-1 ATLAS L = 3· 105 pb-1 1 = 2 S = 12 M = 1 Te. V ü The heavy quark T can be observed for a mass up to ~2 Te. V K. Benslama Hadron Collider Symposium 13
Little Higgs: AH and ZH Signal : di-lepton resonance Reach up to 5. 7 Te. V depending on the angle K. Benslama Hadron Collider Symposium 14
Technicolor 30 fb-1 ü T ATLAS WZ WZ o WZ K. Benslama Hadron Collider Symposium At least 3 charged leptons o with p. T > 25 Ge. V p. T(W), PT(Z) > 40 Ge. V o Use polarization of technirho 15
Excited Quarks & Leptons ü Excited quarks – Reach limit for q* -> q 6. 5 Te. V - Reach for qw: 7 Te. V - Reach for qz: 4. 5 Te. V f=f’=1 L = 300 fb-1, = m* ü Excited electrons ATLAS ü Reach: ~ 3 – 4 Te. V for = 6 Te. V, 300 fb-1 K. Benslama Hadron Collider Symposium 16
Leptoquarks ATLAS ü Motivation – SM extension: lepton-quark symmetry ü Study: Scalar LQ 30 fb-1 - 2 jets + 2 leptons: 1 st and 2 nd generation Sensitivity: M(LQ)~1. 3 Te. V Beta= 1 - 2 jets + Et: 3 rd generation Sensitivity: M(LQ) ~ 1 Te. V Beta= 0. 5 K. Benslama Hadron Collider Symposium 1 st generation 17
New Gauge Bosons (I) CMS A very low luminosity, less than 0. 1 fb-1, should be sufficient to discover Z' bosons at 1 Te. V K. Benslama Hadron Collider Symposium 18
New Gauge Bosons (II) CMS K. Benslama Hadron Collider Symposium 19
Doubly Charged Higgs L-R symmetric model would be a natural extension of the SM Ø SU(2)L x SU(2)R x U(1)B-L Ø predicts new fermions: heavy Majorana neutrino Ø predicts new gauge bosons: WR Ø predicts new Higgs sector Two high p. T leptons with same charge Two high p. T jets Parameters: In this analysis: K. Benslama Hadron Collider Symposium 20
ee, μμ Discovery Reach (a) 100 fb-1 (b) 300 fb-1 ATLAS tau (a) 100 fb-1 (b) 300 fb-1 ~1. 4 Te. V ~400 Ge. V Tevatron (a) 100 fb-1 (b) 300 fb-1 Full = 3 leptons are observed Dashed =4 leptons are observed K. Benslama Te. V Hadron Collider~1. 2 Symposium 21
Summary LHC will explore the Te. V scale in detail with direct discovery potential up to m ~ 5 -6 Te. V New Gauge Bosons? Extra Dimensions? K. Benslama Technicolor? Excited electrons? Hadron Collider Symposium Little Higgs? Black Holes? ? ? 22
Conclusion ü 403 days from now, particle physics will enter a new epoch of its history. ü The LHC will address many of the leading questions in particle physics: - Is nature supersymmetric? - Are there extra dimensions of space? - What unknown mechanism gives mass to particles? Solving these mysteries will be an important chapter in the history of science. K. Benslama Hadron Collider Symposium 23
Backup Slides K. Benslama Hadron Collider Symposium 24
ATLAS & CMS K. Benslama Hadron Collider Symposium 25
ATLAS & CMS at the Beginning? 3 layers of pixels No EE chambers K. Benslama Hadron Collider Symposium 26
The ATLAS Detector Inner Detector (2 T solenoid, |η|<2. 5): Calorimetry: * electromagnetic, |η|<3. 2 * hadronic (central, |η|<1. 7) * hadronic (endcaps, 1. 7<|η|<3. 2) * hadronic (forward, 3. 2<|η|<4. 9) Muon system (~4 T toroid, |η|<2. 7): K. Benslama Hadron Collider Symposium 27
CMS Detector K. Benslama Hadron Collider Symposium 28
ATLAS Trigger & Physics K. Benslama Hadron Collider Symposium 29
Charge sign misidentification K. Benslama Hadron Collider Symposium 30
Jets Calibration using /jet sample K. Benslama Hadron Collider Symposium 31
Large Extra-D: Direct Production Jet+MET K. Benslama Gamma+MET Hadron Collider Symposium 32
Extra-D Models Large Extra-D: Virtual Production K. Benslama Hadron Collider Symposium RS Graviton 33
Constraints on large ED constraint =2 =3 max R (mm) min MD (Te. V) 0. 2 0. 6 SN 1987 A cooling by graviton emission 7 x 10– 4 10 30 9 x 10– 7 0. 8 2. 5 Diffuse cosmic ray background (G(k) → gg ) other reheating scenarios decays after SN explosion 9 x 10– 25 2 x 10– 7 1. 9 heating of neutron stars (trapped G(k) decaying) 8 x 10 - Gravitational force law LEP: g G, ZG, virtual Tevatron K. Benslama 5 167 450 6 90 1700 22 30 3. 5 x 108 5 60 ~1 Te. V Hadron Collider Symposium 34
Radion ü Motivation – Scalar field representing fluctuations of the distance of the 2 branes – To stabilize krc ~ 35 (Golberger & Wise) ü Radion properties – Higgs-like couplings – Mixing to Higgs ü Signal K. Benslama Hadron Collider Symposium 35
Radion ü Other signals – ü x Lf (Te. V) mf=300 mf=600 0 1 4 43 0 10 333 - 1/6 1 2 57 1/6 10 250 - Required luminosity (fb-1) for 5 discovery ü Discrimination Higgs/ – Difficult at LHC – Look at & BR mods K. Benslama (Rizzo et al) Hadron Collider Symposium 36
Black Holes K. Benslama Hadron Collider Symposium 37
New Higgs ++ ü Production – Via WW fusion Forward jet tag essential W+ f++ 300 fb-1 W+ ü Decay – W+W+ to l+ l+ At 1 Te. V; Significance: 5 σ if v’ > 29 Ge. V K. Benslama Hadron Collider Symposium 38
BR Heavy Gauge Bosons e + e - + + - + + Zh cot Cross section and Br. fractions K. Benslama Accessible region for 5 s discovery Hadron Collider Symposium 39
Heavy Leptons ü Basics – Look at sequential leptons: 4 th family – Other models: VF, Chiral F, Singlets F – Final state ll. ZZ ü Analysis – gg & DY – 2 l, 2 Z (4 jets) – Bdg: tt, VV+jets Reach ~ 1 Te. V Depends on Z’ K. Benslama Significance Hadron Collider Symposium 40
- Slides: 40