Diphoton searches. in ATLAS. Marco Delmastro CNRS/IN2P3 LAPP on behalf of the ATLAS Collaboration. Les Rencontres de Moriond EW 2016
|
|
- Lucy Jacobs
- 7 years ago
- Views:
Transcription
1 Diphoton searches in ATLAS Marco Delmastro CNRS/INP LAPP on behalf of the ATLAS Collaboration Les Rencontres de Moriond EW 6 Marco Delmastro Diphoton searches in ATLAS
2 Why diphoton searches? Clean signal over smooth and well known background (e.g. H(5)à γγ) Several extensions of the Standard Model predict high-mass states decaying to two photons Benchmark models HDM Spin- analysis e.g. extended Higgs sector ü 5 physical states h, H, A, H ± ü Under certain conditions, scalar and/or pseudo-scalar states can have sizable branching ratio to diphoton Spin- analysis e.g. Randall-Sundrum graviton Model predicts tower of Kaluza-Klein graviton states with TeV mass scale Phenomenology ü m G* = mass of lightest KK excitation ü κ/m Pl = dimensionless coupling to SM fields Marco Delmastro Diphoton searches in ATLAS
3 Recap of latest Run results Search for scalar diphoton resonances in the mass range 65-6 GeV with the ATLAS detector in pp collision data at s = 8 TeV Phys. Rev. Lett., 78 Search for high-mass diphoton resonances in pp collisions at s = 8 TeV with the ATLAS detector Phys. Rev. D 9, 4 (5) ] [GeV γ dn / dm γ ATLAS s = 8 TeV, Ldt =. fb Data Continuum+H fit (m X = 5 GeV) Continuum+H fit (m X = 5 GeV) Continuum+H fit (m X = 5 GeV) 8 H(5) 6 4 Data 8 Continuum+H fit (m X = 5 GeV) Continuum component of the fit m Events/bin Significance Control region ATLAS Data Total b ackground Reducible background syst stat (reducible) syst stat (total) RS, k/ M Pl =., m G* =.5 TeV RS, k/ M Pl =., m G* =. TeV L dt =. fb s = 8 TeV 4 5 m γ Marco Delmastro Diphoton searches in ATLAS
4 Overview of ATLAS TeV analyses Common pre-selections & photon identification ü E T γ > 4 GeV, E T γ > GeV ü Precision region of EM calorimeter: η <.7,.7.5 excluded ü Tight photon identification based on shower moments in EM calorimeter ü Photon isolation (calorimeter cone + track isolation) SPIN- ANALYSIS Optimized for Higgs-like signal ü E T γ >.4 m γγ, E T γ >. m γγ +% significance for m X > 6 GeV Effectively deplete forward regions As model-independent as possible ü Limit on fiducial cross section Search range ü m X = [ GeV TeV] ü Γ X /m X = [% - %] SPIN- ANALYSIS Loose selection ü E T γ > 55 GeV, E T γ > 55 GeV Preserve acceptance at high mass Use RS graviton as (kinematic) benchmark Search range ü m G = [5 GeV TeV] ü κ/m Pl = [.-.] ü Γ G /m G ~ [.% - %] Γ G ~.44 (κ/m Pl ) Marco Delmastro Diphoton searches in ATLAS 4
5 Photon energy calibration MV regression to calibrate photon cluster energy, optimized on MC ü i.e. Eur.Phys.J. C74 (4) 7 ü EMC longitudinal layers inter-calibration from from data + additional uncertainty Mostly affecting constant term ü Energy scale and resolution corrections validated with TeV Zà ee events At E T γ > - GeV, resolution dominated by constant term ü c =.6% -.5% E E = p a E b E c Entries / GeV 5 4 Data MC Stat. Syst. Unc. + - Z e e Diboson - Z τ + τ Top + - Z e e TeV, 85 pb Uncertainties ü Energy scale: ±(.4%-%) ü Energy resolution (E Tγ = GeV): ±(8%-%) m ee m ee Marco Delmastro Diphoton searches in ATLAS 5 Data/Pred.
6 Photon identification and isolation Identification ü 85% (E T ~5 GeV) -95% (E T ~ GeV) ü Uncertainty: full data/mc difference ±% - ±5% for E T > 5 GeV η dependent (tight) ε ID Simulation Pythia prompt photon MC s = TeV η <.6 iso E T < 4 GeV Converted Unconverted.6 4 E T 8 Isolation ü Calorimeter (ΔR=.4) E T iso <. E T γ +.45 GeV ü Track p T iso (ΔR=.) p T iso <.5 E T γ ü Uncertainty: full data/mc difference Marco Delmastro Diphoton searches in ATLAS E T -. x E T 6 Events < p < 45 T. < η <.6 iso Data Bkg template Sherpa Pythia
7 Sample composition Estimated for both selections using xd-sideband and Matrix Method ü As in SM diphoton cross section measurements (e.g. New J. Phys. 5 () 47) SPIN- ANALYSIS SPIN- ANALYSIS P γγ = % P γγ = % [/GeV] dn/dm γγ s= TeV,. fb Spin- Selection Data yield Estimated yield Estimated γ j+jγ yield Estimated jj yield [/GeV] dn/dm γγ s= TeV,. fb Spin- Selection Data yield Estimated yield Estimated γ j+jγ yield Estimated jj yield m γγ m γγ Matrix method.7 Matrix method.6 xd sidebands.6 xd sidebands m γγ m γγ Marco Delmastro Diphoton searches in ATLAS 7 fraction γγ fraction γγ
8 Events / GeV Signal modeling SPIN- ANALYSIS Heavy Higgs-like model ü Narrow-width (Γ X = 4 MeV) 6 ü Large-width (Γ X % m X ) Powheg line-shape assuming SM couplings convoluted to detector response (ggf) m X ± Γ X Double-Sided Crystal Ball ATLAS Simulation Preliminary s = TeV, X m X = 6 GeV 8 Γ X /m X = 6% Events / GeV 5 5 SPIN- ANALYSIS RS-graviton-like model ü κ/m Pl =. (Γ G =.% m G ) to measure and parameterize detector response (DSCB) Analytical convolution of theoretical line-shape with detector response ATLAS Simulation Preliminary s = TeV, G* γγ m G* = GeV k/m Pl =. (Γ G* /m G* = 5.8%) m γγ m Marco Delmastro Diphoton searches in ATLAS 8
9 Background modeling SPIN- ANALYSIS Functional form à sidebands ü Family of nested functions with increasing d.o.f. ü Validated on MC+data template ü All function parameters free Spurious signal uncertainty ü S+B fits on MC+data template SPIN- ANALYSIS MC+data template à high mass ü Irreducible (γγ) à MC DIPHOX NLO parton level SHERPA γγ including detector simulation, reweighted to DIPHOX m γγ ü Reducible (γj, jγ, jj) à data Inverting tight shower shape criteria Varying loose criteria Mixed according to data-driven purities F-test on binned data ü Validate need of additional d.o.f. (k= chosen) Marco Delmastro Diphoton searches in ATLAS 9
10 Results SPIN- ANALYSIS SPIN- ANALYSIS Events / GeV 4 ATLAS background-only fit Preliminary Data Background-only fit Spin- Selection Events / GeV 4 ATLAS background-only fit Preliminary Data Background-only fit Spin- Selection Data - fitted background events (m γγ > GeV) m γγ Data - fitted background events (m γγ > GeV) Marco Delmastro Diphoton searches in ATLAS m γγ
11 Results SPIN- ANALYSIS SPIN- ANALYSIS Γ X /m X [%] Spin- Selection Local significance [σ] ATLAS k/m Pl Preliminary s = TeV,. fb Spin- Selection Local significance [σ] m X Largest deviation from B-only hypothesis ü m X ~ 75 GeV, Γ X ~ 45 GeV (6%) ü Local Z =.9 σ ü Global Z =. σ m X = [ GeV - TeV] Γ X /m X = [% - %] m G* Largest deviation from B-only hypothesis ü m G ~ 75 GeV, κ/m Pl ~. (Γ G ~ 6% m G ) ü Local Z =.6 σ ü Global Z =.8 σ m X = [5 GeV.5 TeV] κ/m Pl = [..] Marco Delmastro Diphoton searches in ATLAS
12 /N dn/d Njets Properties of sideband and excess regions SPIN- ANALYSIS m γγ = [6-7] GeV m γγ = [7-84] GeV m γγ =[84- ] GeV Spin- Selection Data (6 GeV< m < 7 GeV) Sherpa (6 GeV< m < 7 GeV) Data MC γγ /N dn/d Njets Spin- Selection Data (7 GeV< m < 84 GeV) Sherpa (7 GeV< m < 84 GeV) /N dn/d Njets Spin- Selection N jets Data (m > 84 GeV) Sherpa (m > 84 GeV) SPIN- ANALYSIS N jets N jets N jets /N dn/d Njets.5.4. Spin- Selection Data (6 GeV< m < 7 GeV) Sherpa (6 GeV< m < 7 GeV) /N dn/d Njets.4. Spin- Selection Data (7 GeV< m < 84 GeV) Sherpa (7 GeV< m < 84 GeV) /N dn/d Njets.5.4. Spin- Selection Data (m > 84 GeV) Sherpa (m > 84 GeV) anti-k t R-.4 N jets y j <.4 à p T j > 5 GeV + JVT <.64 Marco Delmastro Diphoton searches in ATLAS N jets.4 < y j < 4.4 à p T j > 5 GeV N jets
13 ] [GeV γγ /N dn/dpt ] [GeV γγ /N dn/dpt Properties of sideband and excess regions SPIN- ANALYSIS m γγ = [6-7] GeV m γγ = [7-84] GeV m γγ =[84- ] GeV Spin- Selection SPIN- ANALYSIS Spin- Selection Data (6 GeV< m < 7 GeV) Sherpa (6 GeV< m < 7 GeV) Data MC γγ γγ pt Data (6 GeV< m < 7 GeV) Sherpa (6 GeV< m < 7 GeV) γγ pt ] [GeV γγ /N dn/dpt ] [GeV γγ /N dn/dpt Data (7 GeV< m < 84 GeV) Spin- Selection Spin- Selection Data (7 GeV< m < 84 GeV) Sherpa (7 GeV< m < 84 GeV) γγ pt Sherpa (7 GeV< m < 84 GeV) γγ pt ] [GeV γγ /N dn/dpt ] [GeV γγ /N dn/dpt Data (m > 84 GeV) Spin- Selection Spin- Selection p T γγ Sherpa (m > 84 GeV) Data (m > 84 GeV) γγ pt Sherpa (m > 84 GeV) γγ pt Marco Delmastro Diphoton searches in ATLAS
14 Limit on fiducial cross-section 4 4 BR [fb] 95% CL Upper Limit on σ fid BR [fb] 95% CL Upper Limit on σ fid 4 Observed CL s limit Expected CL s limit Expected ± σ Expected ± σ Γ X /m X = % Spin- selection Observed CL s limit Expected CL s limit Expected ± σ Expected ± σ m X Γ X /m X = 6 % Spin- Selection m X BR [fb] 95% CL Upper Limit on σ fid BR [fb] 95% CL Upper Limit on σ fid Observed CL s limit Expected CL s limit Expected ± σ Expected ± σ Γ X /m X = % Spin- selection E γ T >.4 m γγ, E γ T >. m γγ 4 E iso T (ΔR=.4) <.5 E γ T + 6 GeV m X ± Γ X Observed CL s limit Expected CL s limit Expected ± σ Expected ± σ SPIN- ANALYSIS m X m X Γ X /m X = % Spin- selection Marco Delmastro Diphoton searches in ATLAS 4
15 Limit on production cross section 95% CL limits on σ BR(G* γγ) [fb] Observed CL s limit Expected CL s Expected ± σ Expected ± σ limit Spin- Selection G*, k/m Pl =.5 95% CL limits on σ BR(G* γγ) [fb] Observed CL s limit Expected CL s Expected ± σ Expected ± σ limit SPIN- ANALYSIS Spin- Selection G*, k/m Pl = m G* m G* 95% CL limits on σ BR(G* γγ) [fb] Observed CL s limit Expected CL s Expected ± σ Expected ± σ limit Spin- Selection G*, k/m Pl =. 95% CL limits on σ BR(G* γγ) [fb] Observed CL s limit Expected CL s Expected ± σ Expected ± σ limit Spin- Selection G*, k/m Pl = m G* Marco Delmastro Diphoton searches in ATLAS 5 m G*
16 Compatibility with 8 TeV data 8 TeV data re-analyzed: latest Run γ calibration + same Run selections + TeV analysis methods Events / GeV 4 SPIN- ANALYSIS Data Background-only fit Spin- Selection s = 8 TeV,. fb Events / GeV 4 ATLAS SPIN- ANALYSIS Preliminary Data Background-only fit Spin- Selection s = 8 TeV,. fb Data - fitted background m γγ.9 σ at m X = 75 GeV, Γ X /m X = 6% Compatibility with TeV scalar ü gg (scaling: 4.7) à compatibility:. σ ü qq (scaling:.7) à compatibility:. σ No significant excess Compatibility with TeV graviton ü gg à compatibility:.7 σ Marco Delmastro Diphoton searches in ATLAS 6 Data - fitted background ü qq à compatibility:. σ m γγ
17 Summary Search for new resonances decaying to diphotons performed with. fb TeV data, with two analyses targeting spin- and spin- scenarios Most of the γγ spectrum consistent with B-only hypothesis Largest deviation from background-only hypothesis observed in broad region around 75 GeV, with global significance. (.8) σ for the spin- (spin-) analysis Numerous cross-checks of events with masses ~ 75 GeV performed 8 TeV data re-analyzed using latest Run calibration, compatibility with TeV results assessed ü Scalar. σ (gg). σ (qq) ü Graviton.7 σ (gg). σ (qq) More data needed to verify excess origin: looking forward to 6 LHC run! Marco Delmastro Diphoton searches in ATLAS 7
18 Additional information Marco Delmastro Diphoton searches in ATLAS 8
19 Systematic uncertainties Marco Delmastro Diphoton searches in ATLAS 9
20 Background modeling Relative uncertainty total sys reducible irreducible purity isolation SPIN- ANALYSIS m γγ Marco Delmastro Diphoton searches in ATLAS
21 Acceptance SPIN- ANALYSIS Fiducial region ü E γ (truth) T >.4 m γγ, E γ(truth) T >. m γγ ü E iso (truth) T (R=.4) <.5 E γ (truth T ) + 6 GeV ü m X ± Γ X ggf as baseline ü Difference to alternative production modes as systematics (ggf, VBF, WH, ZH, tth) As model-independent as possible C X = 55%-7% for m X = -7 GeV SPIN- ANALYSIS Total selection efficiency RS graviton as benchmark A G C G = 45%-6% for m G = 5- GeV Source of uncertanty Scalar Common Graviton Photon energy scale and resolution negligible Marco Delmastro Diphoton searches in ATLAS
22 Compatibility between spin- and spin- analyses Events in spin- analysis are subset of events in spin- analysis for m γγ > 85 GeV, so two analyses are not independent ü Resampling techniques (bootstrap) Union dataset is sliced into N blocks with events in each block. N blocks are randomly picked without considering possible duplication (i.e. the same block could be selected for more than one time). Resampled dataset will then pass spin- and spin- selections, outcome spectra are fed into max LL S+B fit assuming same signal hypothesis Procedure is repeated many times until decent statistics are accumulated for compatibility check Assuming spin- signal:. σ Assuming spin- signal:.9 σ Marco Delmastro Diphoton searches in ATLAS
23 8 TeV analysis selections Marco Delmastro Diphoton searches in ATLAS
24 * γγ /N dn/dcosθ Properties of sideband and excess regions SPIN- ANALYSIS Data (6 GeV< m < 7 GeV) 4 Spin- Selection SPIN- ANALYSIS Sherpa (6 GeV< m < 7 GeV) * cosθγγ * γγ /N dn/dcosθ Spin- Selection Data (7 GeV< m < 84 GeV) Sherpa (7 GeV< m < 84 GeV) * cosθγγ * γγ /N dn/dcosθ Spin- Selection cosθ * γγ m γγ = [6-7] GeV m γγ = [7-84] GeV m γγ =[84- ] GeV Data (m > 84 GeV) Sherpa (m > 84 GeV) * cosθγγ * γγ /N dn/dcosθ 5 4 Spin- Selection Data MC γγ Data (6 GeV< m < 7 GeV) Sherpa (6 GeV< m < 7 GeV) * γγ /N dn/dcosθ 7 Data (7 GeV< m < 84 GeV) Spin- Selection Sherpa (7 GeV< m < 84 GeV) * γγ /N dn/dcosθ Spin- Selection Data (m > 84 GeV) Sherpa (m > 84 GeV) * cosθγγ * cosθγγ * cosθγγ Marco Delmastro Diphoton searches in ATLAS 4
25 ] [GeV miss /N dn/de T Properties of sideband and excess regions SPIN- ANALYSIS m γγ = [6-7] GeV m γγ = [7-84] GeV m γγ =[84- ] GeV Spin- Selection SPIN- ANALYSIS Data (6 GeV< m < 7 GeV) Sherpa (6 GeV< m < 7 GeV) Data MC γγ miss E T ] [GeV miss /N dn/de T Spin- Selection Data (7 GeV< m < 84 GeV) Sherpa (7 GeV< m < 84 GeV) miss E T ] [GeV miss /N dn/de T Spin- Selection E T miss Data (m > 84 GeV) Sherpa (m > 84 GeV) miss E T ] [GeV miss /N dn/de T Spin- Selection Data (6 GeV< m < 7 GeV) Sherpa (6 GeV< m < 7 GeV) miss E T ] [GeV miss /N dn/de T.5 Data (7 GeV< m < 84 GeV).4... Spin- Selection Sherpa (7 GeV< m < 84 GeV) miss E T ] [GeV miss /N dn/de T Spin- Selection Data (m > 84 GeV) Sherpa (m > 84 GeV) miss E T Marco Delmastro Diphoton searches in ATLAS 5
26 EOYE NW results Local p-value 4 5 σ σ σ σ 4σ Observed m X BR [fb] 95% CL Upper Limit on σ fid Observed Expected ± σ ± σ m X Largest deviation from B-only hypothesis ü m X ~ 75 GeV ü Local Z =.6 σ ü Global Z =. σ m X = [ GeV - TeV] Marco Delmastro Diphoton searches in ATLAS 6
27 Recap of latest Run results Search for scalar diphoton resonances in the mass range 65-6 GeV with the ATLAS detector in pp collision data at s = 8 TeV Phys. Rev. Lett., 78 Search for high-mass diphoton resonances in pp collisions at s = 8 TeV with the ATLAS detector Phys. Rev. D 9, 4 (5) ] [GeV γ dn / dm γ 95% CL limit on σ fid BR [fb] ATLAS s = 8 TeV, Ldt =. fb Data Continuum+H fit (m X = 5 GeV) Continuum+H fit (m X = 5 GeV) Continuum+H fit (m X = 5 GeV) Data Continuum+H fit (m X = 5 GeV) Continuum component of the fit ATLAS internal s = 8 TeV, Ldt =. fb Observed Expected ± σ ± σ m Events/bin Significance Control region ATLAS Data Total background Reducible background syst stat (reducible) syst stat (total) RS, k/ M Pl =., m G* =.5 TeV RS, k/ M Pl =., m G* =. TeV L dt =. fb s = 8 TeV 4 5 [pb] )γ BR(G* σ - - m γ ATLAS Observed limit Expected limit s= 8 TeV Expected ± σ G* γ Expected ± σ k/ M Pl =. k/ M Pl =. k/ M Pl =.5 k/ M Pl =. L dt =. fb m X m G* [TeV] Marco Delmastro Diphoton searches in ATLAS 7-4
28 Recap of latest Run results Search for Extra Dimensions in diphoton events using proton-proton collisions recorded at s = 7 TeV with the ATLAS detector at the LHC New J. Phys. 5 () 47 Events/bin ATLAS L dt = 4.9 fb s = 7 TeV - - Control region data Total Background Reducible Background syst stat (total) syst stat (reducible) RS, k/ M Pl =., m G =.5 TeV ADD, GRW, M S =.5 TeV Significance - 4 m γ Marco Delmastro Diphoton searches in ATLAS 8
29 Data sample & Selections Luminosity & Trigger ü Trigger: E T γ 5 GeV, E T γ > 5 GeV + loose EM shower identification ~99% efficient w.r.t. final selections ü. fb ± 5% SCALAR E T γ >.4 m γγ, E T γ >. m γγ 79 events (m γγ > 5 GeV) 878 events (m γγ > GeV) GRAVITON E T γ > 55 GeV, E T γ > 55 GeV 566 events (m γγ > GeV) Marco Delmastro Diphoton searches in ATLAS 9
30 Background modeling IRREDUCIBLE born box parton fragmentation REDUCIBLE jets in γj and jj events with a neutral meson decaying in collimated photon pairs Marco Delmastro Diphoton searches in ATLAS
31 A photon showers in the EMC. Most of its energy is lost in Pb Electrons in EM shower ionize LAr Ionization electrons produce current Current is collected, amplified, shaped, sampled and digitized for each EMC cell E in-situ intercalibration MVA calibration cluster corrections clustering electronic calibration Photon energy scale is adjusted to EM scale from Zà ee events Cluster energy is corrected for loss to get photon energy Cluster energies are corrected for detectors effects Cells are grouped in clusters Energy in a cell is reconstructed from signal samples Marco Delmastro Diphoton searches in ATLAS
32 ATLAS liquid argon electromagnetic calorimeters sampling calorimeter Pb-LAr S X Cells in Layer ϕ η =.45.5 Trigger Tower η =. η = S 47 mm 6X E E = p a E % 5 MeV.7% b E c S 5 mm 4.X.7X ϕ=.45x4 Trigger Tower ϕ =. S (Presampler) Energy loss correction S (Strips) γ/π separation 4. X S 6.8mmx 4 =47.mm 7.5mm/8 = 4.69 mmm η =. ϕ =.45 Square cells in Layer S (Middle) Main energy deposit 6 X S (Back) High energy showers X ϕ Cells in PS η ϕ =.5. η =.5 Strip cells in L ayer Marco Delmastro Simulation of Electron and Photons in ATLAS η
33 ATLAS Inner Detector + IBL! Properties of track from charged particles ü momentum ü charge Transition Radiation ü e/pi discrimination e/γ discrimination γ conversion reconstruction Marco Delmastro Simulation of Electron and Photons in ATLAS
34 Electrons and photons in ATLAS Electron and photon candidates in ATLAS are built from EM sliding window fixed-size rectangular clusters, that can be associated to tracks ϕ ü η φ = (Barrel),.5.5 (Endcap) ü Unifed between electrons and photons in 5 ü Size is trade-off between energy leakage and noise pickup ϕ η η Cells in EM clusters are calibrated to EM scale ü Including expected average sampling fraction, from simulated electron at GeV Several corrections needed for e and γ, mostly based on simulation ü e.g. energy losses outside cluster, losses in upstream material, variable sampling fraction Marco Delmastro Simulation of Electron and Photons in ATLAS 4
35 Photon conversion reconstruction Candidate photon conversion vertices reconstructed from tracks pre-selected as loosely matching EMC clusters ü or tracks ü -track conversions from tracks that missing the hit in innermost ID layer Photon reconstruction expected efficiency ü ~ 98% for photons E T > 5 GeV ü > 99% for unconverted photons ü ~ 95% for converted (R < 8 cm) Expected fraction of converted photons ü ~ % at η - ~ 45% η.6 Relative fraction of reconstructed photon conversion depends on: ü Material upstream EMC ü In MC, on conversion model Marco Delmastro Simulation of Electron and Photons in ATLAS 5
36 Photon conversion reconstruction Fraction of photon candidates Unconverted Converted Single track conversion Double track conversion s = TeV, L dt = 9 pb γ γ η <.7 (.7 < η.5 excluded), E γ T > 5 GeV Fraction of photon candidates. Unconverted Converted Single track conversion Double track conversion s = TeV, L dt = 9 pb γ γ η <.7 (.7 < η.5 excluded), E γ T > 5 GeV γ E T γ η Marco Delmastro Diphoton searches in ATLAS 6
37 Photon pointing z position of diphoton primary vertex obtained by combining average beam-spot position with photon pointing, enhanced by using tracks from photon conversions with conversion radii in Si volume ü Resolution ~5 mm in z direction NN discriminant with Σp T,Σp T, diphoton balancing with vertex tracks, trajectory from calorimeter segmentation (z pointing) to choose best vertex candidate ü After this procedure contribution of the opening angle resolution to the mass resolution is negligible. ü Efficiency to reconstruct the correct primary vertex within ±. mm is about 88%. ε PV Data Z ee, ignoring lepton tracks MC Z ee, ignoring lepton tracks MC H γγ (ggf), m =5 GeV H Number of Primary Vertices Marco Delmastro Diphoton searches in ATLAS 7
38 Photon identification S ( Back ) ϒ candidate π candidate S ( Middle ) S ( Strips ) Presampler η Marco Delmastro Diphoton searches in ATLAS 8
39 Photon identification Marco Delmastro Diphoton searches in ATLAS 9
40 Photon identification 5 (tight) ε ID.95 Simulation (tight) ε ID.95 Simulation Pythia prompt photon MC s = TeV η <.6 iso E T < 4 GeV Converted Unconverted Pythia prompt photon MC s = TeV.6 < η <.7 iso E T < 4 GeV Converted Unconverted.6 4 E T E T 8 (tight) ε ID Simulation Pythia prompt photon MC s = TeV.5 < η <.8 iso E T < 4 GeV Converted Unconverted E T E T Marco Delmastro Diphoton searches in ATLAS 4 (tight) ε ID Simulation Pythia prompt photon MC s = TeV.8 < η <.7 iso E T < 4 GeV Converted Unconverted 8
41 Photon isolation Calorimetric isolation energy corrected event-by-event ü Leakage of photon cluster ü Underlying event and pileup contributions Average correction for PV ~54MeV Cacciari, Salam and Soyez, JHEP 4, 5 (8) Cacciari, Salam and Sapeta, JHEP 4, 65 () Per-event isolation efficiency H (ggf), m s = 8 TeV s = TeV ATLAS Simulation Preliminary H = 5 GeV Number of primary vertices Marco Delmastro Diphoton searches in ATLAS 4
42 Photon isolation 5 Events < p < 45 T. < η <.6 Data Bkg template Sherpa Pythia Events < p < 45 T.6 < η <.7 Data Bkg template Sherpa Pythia iso E T -. x E T iso E T -. x E T Events < p < 45 T.5 < η <.8 Data Bkg template Sherpa Pythia Events < p < 45 T.8 < η <.7 Data Bkg template Sherpa Pythia iso E T -. x E T E T -. x E T Marco Delmastro Diphoton searches in ATLAS 4 iso
43 Background estimates xd-sidebands L L sample, leading candidate D isolation template fit Identification cut TIGHT non-tight Control region C Signal region A D B Control region Control region events / GeV ATLAS Data, s γ > 6 GeV E T γγ γj jγ+jj γγ+γj+jγ+jj = 7 TeV, Ldt = 7 pb (leading photon) isol E iso T, iso E T, Identification cut TIGHT non-tight Control region C Signal region A A sample, sub-leading candidate D B Control region Control region events / GeV ATLAS Data, s γ > 6 GeV E T γγ jγ γj+jj γγ+γj+jγ+jj = 7 TeV, Ldt = 7 pb (sub leading photon) E iso T, iso E T, Marco Delmastro photon and diphoton production at ATLAS 4
44 Background estimates Matrix Method Passes or Fails isolation cut ε i = probability for a γ to pass isolation cut (data-driven) f i = probability for a jet to pass isolation cut (data-driven) accounting for the correlation of the isolation energy of the γ candidates Event weights Marco Delmastro photon and diphoton production at ATLAS 44
45 Do we need an additional free parameter? One might be tempted to use a more complex function to fit the data ü If a more complex function f b (x; {p b }) embeds the simpler one f a (x; {p a }) (e.g. there exist a choice of {p b } such that f b (x; {p b }) = one f a (x; {p a }), then the function with more degrees of freedom will have a smaller Χ The problem is to decide whether f b is more motivated than f a ü Eyes are not good judges ü F-test à the function F has Fisher distribution f(f; p, p ) if the added parameter is not improving the model One rejects the hypothesis that the additional parameter if useless if P <.5, where P is the probability of observing a F value at least as extreme as the one in data, if drawn from a Fisher distribution with the same degrees of freedom M. Delmastro on behalf of many High mass diphoton resonance search 45
46 Statistical procedure Marco Delmastro Diphoton searches in ATLAS 46
47 Double-Sided Crystal Ball function Arbitrary Units σ CB Gaussian Distribution σ CB.α Low ATLAS σ CB.α High X γγ Power Law -n Low ~(-m ) Power Law -n High ~(m ) m X m Marco Delmastro Diphoton searches in ATLAS 47
48 Signal modeling Events /( GeV) ATLAS Simulation Internal s = TeV, X m X = 6 GeV = 4 MeV 8 Γ X Events / 5 GeV 5 ATLAS simulation internal m G = GeV k/m Pl = Events /( GeV) ATLAS Simulation Internal s = TeV, X m X = 6 GeV Γ X /m X = 6% m γγ Events / GeV m γγ ATLAS m G = GeV k/m Pl =. simulation internal m γγ m Marco Delmastro Diphoton searches in ATLAS 48
49 JVF Jet Vertex Fraction Marco Delmastro Diphoton searches in ATLAS 49
PoS(Kruger 2010)013. Setting of the ATLAS Jet Energy Scale. Michele Petteni Simon Fraser University E-mail: mpetteni@sfu.ca
Setting of the ALAS Energy Scale Simon Fraser University E-mail: mpetteni@sfu.ca he setting of the energy scale and its uncertainty in the ALAS detector is presented. After a brief introduction of the
More informationJet Reconstruction in CMS using Charged Tracks only
Jet Reconstruction in CMS using Charged Tracks only Andreas Hinzmann for the CMS Collaboration JET2010 12 Aug 2010 Jet Reconstruction in CMS Calorimeter Jets clustered from calorimeter towers independent
More informationarxiv:hep-ph/0310021v2 4 Oct 2003
Physics in Collision - Zeuthen, Germany, June 6-8, 003 arxiv:hep-ph/0300v 4 Oct 003 SEARCHES FOR NEW PARTICLES AT THE ENERGY FRONTIER AT THE TEVATRON Patrice VERDIER LAL, Université Paris-Sud, 9898 Orsay
More informationMeasurement of Neutralino Mass Differences with CMS in Dilepton Final States at the Benchmark Point LM9
Measurement of Neutralino Mass Differences with CMS in Dilepton Final States at the Benchmark Point LM9, Katja Klein, Lutz Feld, Niklas Mohr 1. Physikalisches Institut B RWTH Aachen Introduction Fast discovery
More informationCMS Physics Analysis Summary
Available on the CERN CDS information server CMS PAS RK-10-002 CMS Physics Analysis Summary Contact: cms-pog-conveners-tracking@cern.ch 2010/07/20 Measurement of racking Efficiency he CMS Collaboration
More informationTop rediscovery at ATLAS and CMS
Top rediscovery at ATLAS and CMS on behalf of ATLAS and CMS collaborations CNRS/IN2P3 & UJF/ENSPG, LPSC, Grenoble, France E-mail: julien.donini@lpsc.in2p3.fr We describe the plans and strategies of the
More informationReal Time Tracking with ATLAS Silicon Detectors and its Applications to Beauty Hadron Physics
Real Time Tracking with ATLAS Silicon Detectors and its Applications to Beauty Hadron Physics Carlo Schiavi Dottorato in Fisica - XVII Ciclo Outline The ATLAS Experiment The SiTrack Algorithm Application
More informationTheory versus Experiment. Prof. Jorgen D Hondt Vrije Universiteit Brussel jodhondt@vub.ac.be
Theory versus Experiment Prof. Jorgen D Hondt Vrije Universiteit Brussel jodhondt@vub.ac.be Theory versus Experiment Pag. 2 Dangerous cocktail!!! Pag. 3 The basics in these lectures Part1 : Theory meets
More informationCalorimetry in particle physics experiments
Calorimetry in particle physics experiments Unit n. 8 Calibration techniques Roberta Arcidiacono Lecture overview Introduction Hardware Calibration Test Beam Calibration In-situ Calibration (EM calorimeters)
More informationMeasurement of the Mass of the Top Quark in the l+ Jets Channel Using the Matrix Element Method
Measurement of the Mass of the Top Quark in the l+ Jets Channel Using the Matrix Element Method Carlos Garcia University of Rochester For the DØ Collaboration APS Meeting 2007 Outline Introduction Top
More informationJets energy calibration in ATLAS
Jets energy calibration in ATLAS V.Giangiobbe Università di Pisa INFN sezione di Pisa Supported by the ARTEMIS Research Training Network Workshop sui Monte Carlo, la Fisica e le Simulazioni a LHC V.Giangiobbe
More informationTop-Quark Studies at CMS
Top-Quark Studies at CMS Tim Christiansen (CERN) on behalf of the CMS Collaboration ICHEP 2010, Paris 35th International Conference on High-Energy Physics tt 2 km 22 28 July 2010 Single-top 4 km New Physics
More informationStudy of the B D* ℓ ν with the Partial Reconstruction Technique
Study of the B D* ℓ ν with the Partial Reconstruction Technique + University of Ferrara / INFN Ferrara Dottorato di Ricerca in Fisica Ciclo XVII Mirco Andreotti 4 March 25 Measurement of B(B D*ℓν) from
More informationt th signal: theory status
t th signal: theory status M.V. Garzelli MTA - DE Particle Physics Research Group, Univ. Debrecen, Hungary e-mail: garzelli@to.infn.it LHC HXSWG Workshop CERN, June 12-13th, 2014 t th production at LHC
More informationBounding the Higgs width at the LHC
Bounding the Higgs width at the LHC Higgs XSWG workshop, June 2014 John Campbell, Fermilab with K. Ellis, C. Williams 1107.5569, 1311.3589, 1312.1628 Reminder of the method This is the essence of the original
More informationHighlights of Recent CMS Results. Dmytro Kovalskyi (UCSB)
Highlights of Recent CMS Results Dmytro Kovalskyi (UCSB) Introduction Number of CMS publication is over 0 already It is very hard to review all the recent results in one talk This talk concentrates on
More informationValidation of the MadAnalysis 5 implementation of ATLAS-SUSY-13-05
Validation of the MadAnalysis 5 implementation of ATLAS-SUSY-3-5 Guillaume Chalons (LPSC Grenoble) email: chalons@lpsc.in2p3.fr October 27, 24 Abstract In this note we summarise our validation of the ATLAS
More informationSingle-Top Production at the Tevatron and the LHC: Results and Prospects
Single-Top Production at the Tevatron and the LHC: Results and Prospects Wolfgang Wagner Bergische Universität Wuppertal DESY Zeuthen, June 16, 2011 Content: 1) Introduction / History 2) Experimental Status
More informationATLAS NOTE ATLAS-CONF-2010-063. July 21, 2010. Search for top pair candidate events in ATLAS at s = 7 TeV. The ATLAS Collaboration.
ATLAS NOTE ATLAS-CONF-2010-063 July 21, 2010 Search for top pair candidate events in ATLAS at s = 7 TeV The ATLAS Collaboration Abstract A search is performed for events consistent with top quark pair
More informationHow To Find The Higgs Boson
Dezső Horváth: Search for Higgs bosons Balaton Summer School, Balatongyörök, 07.07.2009 p. 1/25 Search for Higgs bosons Balaton Summer School, Balatongyörök, 07.07.2009 Dezső Horváth MTA KFKI Research
More informationSingle Top Production at the Tevatron
Single Top Production at the Tevatron Daniel Wicke (Bergische Universität Wuppertal) Introduction Outline DØ Cross Section CDF Results DØ V tb Conclusions Revision : 1.7 DESY-Zeuthen, 21-Feb-2007 1 Introduction
More informationPoS(LHCPP2013)033. Rare B meson decays at LHC. Francesco Dettori Nikhef and Vrij Universiteit, Amsterdam E-mail: fdettori@nikhef.nl.
Nikhef and Vrij Universiteit, Amsterdam E-mail: fdettori@nikhef.nl Paolo Iengo INFN Napoli E-mail: paolo.iengo@cern.ch Luca Martini INFN Pisa E-mail: Luca.Martini@cern.ch Rare decays of B mesons are fundamental
More informationTracking/Vertexing/BeamSpot/b-tag Results from First Collisions (TRK-10-001)
Tracking/Vertexing/BeamSpot/b-tag Results from First Collisions (TRK-1-1) Yanyan Gao, Fermilab on behalf of Tracking-Btagging POGs 3 March 21 / CERN CMS General Weekly Meeting: GWM8 Contributors and Acknowledgement
More informationTrack Trigger and Modules For the HLT
CMS L1 Track Trigger for SLHC Anders Ryd for the CMS Track Trigger Task Force Vertex 2009 Sept. 13-18, 2009 L=1035 cm-2s-1 Outline: SLHC trigger challenge Tracking triggers Track trigger modules Simulation
More informationHow To Teach Physics At The Lhc
LHC discoveries and Particle Physics Concepts for Education Farid Ould- Saada, University of Oslo On behalf of IPPOG EPS- HEP, Vienna, 25.07.2015 A successful program LHC data are successfully deployed
More informationCMS Tracking Performance Results from early LHC Running
CMS Tracking Performance Results from early LHC Running CMS PAPER TRK-10-001 L. Spiegel, K. Stenson, M. Swartz 1 First Collisions Tracking Paper Provide description of tracker, tracking algorithm, and
More informationThe TOTEM experiment at the LHC: results and perspective
The TOTEM experiment at the LHC: results and perspective Edoardo Bossini Università degli studi di Siena and INFN-Pisa (on behalf of the TOTEM collaboration) Trieste, 24 Settembre 2013 OUTLINE: Detector
More informationThe accurate calibration of all detectors is crucial for the subsequent data
Chapter 4 Calibration The accurate calibration of all detectors is crucial for the subsequent data analysis. The stability of the gain and offset for energy and time calibration of all detectors involved
More informationPhysik des Higgs Bosons. Higgs decays V( ) Re( ) Im( ) Figures and calculations from A. Djouadi, Phys.Rept. 457 (2008) 1-216
: Higgs decays V( ) Re( ) Im( ) Figures and calculations from A. Djouadi, Phys.Rept. 457 (2008) 1-216 1 Reminder 10.6.2014 Higgs couplings: 2 Reminder 10.6.2014 Higgs BF as a function of mh Higgs total
More informationarxiv:1508.07811v1 [hep-ph] 31 Aug 2015
DESY 5-47 RAL-P-05-007 reating jet correlations in high pile-up at hadron colliders arxiv:508.078v [hep-ph] 3 Aug 05 F. Hautmann,, H. Jung, 3, 4 and H. Van Haevermaet 4 Rutherford Appleton Laboratory &
More informationVertex and track reconstruction with the ALICE Inner Tracking System
Vertex and track reconstruction with the ALICE Inner Tracking System The 5th International Nordic "LHC and Beyond" Workshop St.Petersburg, 8-11 June 2010 Leonardo Milano Univ. & INFN, Torino for the ALICE
More informationPHYSICS WITH LHC EARLY DATA
PHYSICS WITH LHC EARLY DATA ONE OF THE LAST PROPHETIC TALKS ON THIS SUBJECT HOPEFULLY We may have some two month of the Machine operation in 2008 LONG HISTORY... I will extensively use: Fabiola GIANOTTI
More informationDelphes, a framework for fast simulation of a general purpose LHC detector
Delphes, a framework for fast simulation of a general purpose LHC detector S. Ovyn and X. Rouby Center for Particle Physics and Phenomenology (CP3) Université catholique de Louvain B-1348 Louvain-la-Neuve,
More informationATLAS NOTE ATLAS-CONF-2013-108. November 28, 2013. Evidence for Higgs Boson Decays to theτ + τ Final State with the ATLAS Detector
ATLAS NOTE ATLAS-CONF-1-8 November 8, 1 Evidence for Higgs Boson Decays to theτ + τ Final State with the ATLAS Detector The ATLAS Collaboration Abstract ATLAS-CONF-1-8 8 November 1 A search for the Higgs
More informationvariables to investigate Monte Carlo methods of t t production
Using the M 2 and variables to investigate Monte Carlo methods of t t production Caitlin Jones September 8, 25 Abstract In this project the behaviour of Monte Carlo simulations for the event t t! ` `+b
More informationSearching for Physics Beyond the Standard Model at GlueX
Searching for Physics Beyond the Standard Model at GlueX Justin Stevens & Mike Williams Department of Physics Massachusetts Institute of Technology GlueX Physics Meeting August 13 th, 2012 Mike Williams
More informationCross section, Flux, Luminosity, Scattering Rates
Cross section, Flux, Luminosity, Scattering Rates Table of Contents Paul Avery (Andrey Korytov) Sep. 9, 013 1 Introduction... 1 Cross section, flux and scattering... 1 3 Scattering length λ and λ ρ...
More informationarxiv:nucl-ex/0507023v2 18 Jul 2005
Diffraction Dissociation - 50 Years later Sebastian N. White Brookhaven National Laboratory, Upton, N.Y. 11973, USA arxiv:nucl-ex/0507023v2 18 Jul 2005 Abstract. The field of Diffraction Dissociation,
More informationThe Compact Muon Solenoid Experiment. CMS Note. Mailing address: CMS CERN, CH-1211 GENEVA 23, Switzerland. D. J. Mangeol, U.
Available on CMS information server CMS NOTE 6/96 The Compact Muon Solenoid Experiment CMS Note Mailing address: CMS CERN, CH11 GENEVA 3, Switzerland July, 6 Search for χ decays to ττ and SUSY mass spectrum
More informationIMPROVEMENT OF JET ENERGY RESOLUTION FOR SEGMENTED HCAL USING LAYER WEIGHTING TECHNIQUE
IMPROVEMEN OF JE ENERGY RESOLUION FOR SEGMENED HCAL USING LAYER WEIGHING ECHNIQUE V. Andreev 1, I. Golutvin 2, A. Nikitenko 3,V.Palichik 2 1 Lebedev Physical Institute, Moscow, Russia 2 Joint Institute
More informationJET ENERGY CALIBRATION IN ATLAS
JET ENERGY CALIBRATION IN ATLAS by Douglas William Schouten B.Sc., University of British Columbia, 2004 a thesis submitted in partial fulfillment of the requirements for the degree of Master of Science
More informationH & II in Inclusive Jet Production
on behalf of the Collaboration Universität Hamburg, Institut für Experimentalphysik, Luruper Chaussee 49, 76 Hamburg, Germany E-mail: monica.turcato@desy.de A summary of the most recent results by the
More informationSearch for Dark Matter at the LHC
Search for Dark Matter at the LHC Steven Lowette Vrije Universiteit Brussel - IIHE 19 November 2014 3rd CosPa Meeting Université de Liège Content Introduction Generic DM searches at the LHC Explicit DM
More informationTheoretical Particle Physics FYTN04: Oral Exam Questions, version ht15
Theoretical Particle Physics FYTN04: Oral Exam Questions, version ht15 Examples of The questions are roughly ordered by chapter but are often connected across the different chapters. Ordering is as in
More informationInformation about the T9 beam line and experimental facilities
Information about the T9 beam line and experimental facilities The incoming proton beam from the PS accelerator impinges on the North target and thus produces the particles for the T9 beam line. The collisions
More informationPart 4 fitting with energy loss and multiple scattering non gaussian uncertainties outliers
Part 4 fitting with energy loss and multiple scattering non gaussian uncertainties outliers material intersections to treat material effects in track fit, locate material 'intersections' along particle
More informationBasic Concepts in Nuclear Physics
Basic Concepts in Nuclear Physics Paolo Finelli Corso di Teoria delle Forze Nucleari 2011 Literature/Bibliography Some useful texts are available at the Library: Wong, Nuclear Physics Krane, Introductory
More informationGamma-rays from Dark Matter Mini-Spikes in Andromeda Galaxy M31. Mattia Fornasa Dipartimento di Fisica G. Galilei I.N.F.N. Padova
Gamma-rays from Dark Matter Mini-Spikes in Andromeda Galaxy M31 Mattia Fornasa Dipartimento di Fisica G. Galilei I.N.F.N. Padova based on astro-ph/0703757 by M. Fornasa, M. Taoso and G.Bertone Journal
More informationSilicon Sensors for CMS Tracker at High-Luminosity Environment - Challenges in particle detection -
timo.peltola@helsinki.fi Finnish Society for Natural Philosophy, Helsinki, 17 February 2015 Silicon Sensors for CMS Tracker at High-Luminosity Environment - Challenges in particle detection - Timo Peltola
More informationRisultati recenti dell'esperimento CMS ad LHC e prospettive per il run a 14 TeV
Risultati recenti dell'esperimento CMS ad LHC e prospettive per il run a 14 TeV Luca Lista INFN Napoli 1 78 reconstructed vertices CMS experiment CMS recorded 5fb-1 at 7 TeV and 20 fb-1 at 8 TeV 2 Electroweak
More informationarxiv:hep-ph/0310009v1 1 Oct 2003
arxiv:hep-ph/319v1 1 Oct 23 HADRONISATION AT LEP ELI BEN-HAIM Laboratoire de l Accélérateur Linéaire (L.A.L.), Université Paris-Sud, Bâtiment 2, BP 34, F-91898 Orsay cedex, France An overview of recent
More informationStatus of ALICE activities within FKPPL LIA
Status of ALICE activities within FKPPL LIA 1 Development of the online monitoring software for the ALICE Muon Trigger And Suppression Study for Υ S A N G - U N A H N K O N K U K U N I V E R S I T Y S
More informationMars Atmosphere and Volatile EvolutioN (MAVEN) Mission
Mars Atmosphere and Volatile EvolutioN (MAVEN) Mission MAVEN Science Community Workshop December 2, 2012 Particles and Fields Package Solar Energetic Particle Instrument (SEP) Davin Larson and the SEP
More informationATLAS Test Beam Analysis in Stockholm: An Overview
ATLAS Test Beam Analysis in Stockholm: An Overview Elin Bergeås, Stockholm University Stand-alone test beam 2003 and before - test beam targeted at TileCal modules only Combined test beam 2004 - test beam
More informationStatus Report of the Gerda Phase II Startup
Status Report of the Gerda Phase II Startup Valerio D Andrea on behalf of the Gerda Collaboration Gran Sasso Science Institute (INFN), L Aquila ICNPA 2016 18th International Conference on Neutrino Physics
More informationImplications of CMS searches for the Constrained MSSM A Bayesian approach
Implications of CMS searches for the Constrained MSSM A Bayesian approach Małgorzata Kazana, Yue-Lin Sming Tsai On behalf of the BayesFITS group National Centre for Nuclear Research Warsaw, Poland BayesFITS,
More informationRare decays in quark flavour physics
Available online at www.sciencedirect.com Nuclear and Particle Physics Proceedings 73 75 (6) 5 59 www.elsevier.com/locate/nppp Rare decays in quark flavour physics Johannes Albrecht On behalf of the collaboration
More informationRecent SiD Tracking Studies at CU (and Ancient Outer Tracker Studies at SLAC)
Recent SiD Tracking Studies at CU (and Ancient Outer Tracker Studies at SLAC) Steve Wagner, University of Colorado, Boulder I did realistic pattern recognition studies for the SiD Barrel Outer Tracker
More informationBNL Contribution to ATLAS
BNL Contribution to ATLAS Software & Performance S. Rajagopalan April 17, 2007 DOE Review Outline Contributions to Core Software & Support Data Model Analysis Tools Event Data Management Distributed Software
More informationComparisons between 2003 CMS ECAL TB data and a Geant 4 MC
Comparisons between 2003 CMS CAL TB data and a Geant 4 MC P. Meridiani LCG Validation Meeting 7 th July 2004 Outline CMS lectromagnetic calorimeter and 2003 TB h4sim http://cmsdoc.cern.ch/~h4sim/ (What
More informationMiddle East Technical University. Studying Selected Tools for HEP: CalcHEP
Middle East Technical University Department of Physics Advanced Selected Problems in Physics Studying Selected Tools for HEP: CalcHEP Author: Jack Yakup Araz Supervisor: Assoc. Prof Ismail Turan December
More informationPerfect Fluidity in Cold Atomic Gases?
Perfect Fluidity in Cold Atomic Gases? Thomas Schaefer North Carolina State University 1 Elliptic Flow Hydrodynamic expansion converts coordinate space anisotropy to momentum space anisotropy Anisotropy
More informationarxiv:1402.0675v1 [physics.ins-det] 4 Feb 2014
Preprint typeset in JINST style - HYPER VERSION Operation and performance of the CMS tracker arxiv:1402.0675v1 [physics.ins-det] 4 Feb 2014 Viktor Veszpremi for the CMS Collaboration a a Wigner Research
More informationarxiv:hep-ph/9607427v1 25 Jul 1996
DFTT 44/96 IFT-96-16 MPI-PhT/96-63 hep-ph/967427 arxiv:hep-ph/967427v1 25 Jul 1996 New proton polarized structure functions in charged current processes at HERA M. Anselmino, P. Gambino, J. Kalinowski,1
More informationPerfect Fluidity in Cold Atomic Gases?
Perfect Fluidity in Cold Atomic Gases? Thomas Schaefer North Carolina State University 1 Hydrodynamics Long-wavelength, low-frequency dynamics of conserved or spontaneoulsy broken symmetry variables τ
More informationA Guide to Detectors Particle Physics Masterclass. M. van Dijk
A Guide to Particle Physics Masterclass M. van Dijk 16/04/2013 How detectors work Scintillation Ionization Particle identification Tracking Calorimetry Data Analysis W & Z bosons 2 Reconstructing collisions
More informationHiggs and Electroweak Physics
Higgs and Electroweak Physics [theory summary] Southampton University & Rutherford Appleton LAB WIN2015 June 12, 2015, MPIK Heidelberg 1 Present: impressive success of LHC RUN 1 on the Higgs&EW Physics
More informationSolid State Detectors = Semi-Conductor based Detectors
Solid State Detectors = Semi-Conductor based Detectors Materials and their properties Energy bands and electronic structure Charge transport and conductivity Boundaries: the p-n junction Charge collection
More informationProton tracking for medical imaging and dosimetry
Proton tracking for medical imaging and dosimetry J.Taylor, P.Allport, G.Casse For the PRaVDA Consortium 1 Background and motivation - What is the PRaVDA experiment? - Why are we using Monte Carlo? GEANT4
More informationSelected Results on Diffraction at HERA
Selected Results on Diffraction at HERA Grzegorz Gach Various Faces of QCD May 014 Grzegorz Gach Selected Results on Diffraction at HERA 1 HERA DESY, Hamburg 199-007 e/e + - p 7.5 GeV 80 GeV 90 GeV Ldt
More informationPrHEP JHW2002. Experiments on high energy reactions in the diffractive regime at LHC. 1. Introduction. Twenty-sixth Johns Hopkins Workshop
PROCEEDINGS Experiments on high energy reactions in the diffractive regime at LHC Helsinki Institute for Physics, c/o CERN, Route de Meyrin, CH-1211 Geneva 23, Switzerland E-mail: Stefan.Tapprogge@cern.ch
More informationHigh Energy Physics. Lecture 4 More kinematics and a picture show of particle collisions
High Energy Physics Lecture 4 More kinematics and a picture show of particle collisions 1 Recall from the previous lecture: the momentum of the scattered Particle in an elastic collision is given by p
More informationFTK the online Fast Tracker for the ATLAS upgrade
FTK the online Fast Tracker for the ATLAS upgrade Kostas Kordas Aristotle University of Thessaloniki Annual EESFYE mtg, University of the Aegean, Chios, 25-29 April 2013 Overview ATLAS Trigger and DAQ
More informationThe LHCb Tracking System. Jeroen van Hunen
The LHCb Tracking System Jeroen van Hunen The LHCb Experiment LHCb at Point 8 : a lot of activity! LHCb : a B-physics experiment that is being constructed for : Precision measurements of the CPviolation
More informationarxiv:1007.1988v2 [physics.ins-det] 27 Jul 2010 The CMS Collaboration
EUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH (CERN) CERN-PH-EP/-19 /7/14 -TRK--1 Tracking Performance Results from Early LHC Operation arxiv:7.1988v [physics.ins-det] 7 Jul The Collaboration Abstract The
More informationOperation and Performance of the CMS Silicon Tracker
Operation and Performance of the CMS Silicon Tracker Manfred Krammer 1 on behalf of the CMS Tracker Collaboration Institute of High Energy Physics, Austrian Academy of Sciences, Vienna, Austria Abstract.
More informationFrom Jet Scaling to Jet Vetos
From Jet Scaling to Jet Vetos Heidelberg DESY, 2/202 LHC Higgs analyses Two problems for LHC Higgs analyses [talks Rauch, Englert] observe H b b decays [fat Higgs jets, Marcel s talk] 2 understand jet
More informationCeSOX sensitivity studies
CeSOX sensitivity studies Ma#hieu VIVIER, Guillaume MENTION CEA- Saclay, DSM/IRFU/SPP CeSOX kick- off meecng Paris, February 5 th CeSOX experimental parameters L/E spectrum modeling and χ 2 Model computes
More informationMasses in Atomic Units
Nuclear Composition - the forces binding protons and neutrons in the nucleus are much stronger (binding energy of MeV) than the forces binding electrons to the atom (binding energy of ev) - the constituents
More information0. 663 ± 0. 006 fm and 0. 63 ± 0. 05. Th K meson result is provisional.
305 MEASUREMENT O PON AND KAON ORM ACTORS AT NA7 (RASCAT, MLAN, PSA, TURN, TRESTE, ROYAL HOLLOWAY COLLEGE, SOUTHAMPTON) S. G.. RANK University of Southampton The electromagnetic form factors of and K mesons
More informationTHE TOP QUARK Updated September 2013 by T.M. Liss (Univ. Illinois), F. Maltoni (Univ. Catholique de Louvain), and A. Quadt (Univ. Göttingen).
1 THE TOP QUARK Updated September 2013 by T.M. Liss (Univ. Illinois), F. Maltoni (Univ. Catholique de Louvain), and A. Quadt (Univ. Göttingen). A. Introduction The top quark is the Q = 2/3, T 3 = +1/2
More informationPROSPECT: Precision Reactor Oscillation and Spectrum experiment
PROSPECT: Precision Reactor Oscillation and Spectrum experiment DAVID MARTINEZ CAICEDO on behalf of PROSPECT collaboration ILLINOIS INSTITUTE OF TECHNOLOGY NUFACT 2015 AUGUST 14th 2015 1 Outline Motivations:
More informationSimulation of Neutron Backgrounds from the ILC Extraction Line Beam Dump. Siva Darbha. Office of Science, SULI Program. University of Toronto
SLAC-TN-07-013 August 2007 Simulation of Neutron Backgrounds from the ILC Extraction Line Beam Dump Siva Darbha Office of Science, SULI Program University of Toronto Stanford Linear Accelerator Center
More informationMartino Margoni Universita` di Padova & INFN (on behalf of the BaBar Collaboration)
B Xs/d γ & B + - Xs/d l l Martino Margoni Universita` di Padova & INFN (on behalf of the BaBar Collaboration) Outlook: B Xs/d γ : Motivations Xsγ (Belle), Acp (Xs+d γ) (BaBar), Vtd/Vts (BaBar) Spectral
More informationHIGH-ENERGY COLLIDER PARAMETERS: e + e Colliders (I)
28. High-energy collider parameters 1 HIGH-ENERGY COLLIDER PARAMETERS: e + e Colliders (I) Updated in early 2012 with numbers received from representatives of the colliders (contact J. Beringer, LBNL).
More informationIntroduction to the Monte Carlo method
Some history Simple applications Radiation transport modelling Flux and Dose calculations Variance reduction Easy Monte Carlo Pioneers of the Monte Carlo Simulation Method: Stanisław Ulam (1909 1984) Stanislaw
More informationFundamental Physics at Extreme High Energies
Fundamental Physics at Extreme High Energies Michael Kachelrieß NTNU, Trondheim [] Outline: Introduction Testing (new?) strong interactions Lorentz invariance violation Topological defects & superheavy
More informationarxiv:hep-lat/9704002v1 6 Apr 1997
Quenched Hadron Spectrum and Decay Constants on the Lattice L. Giusti 1 Scuola Normale Superiore, P.zza dei Cavalieri 7 and INFN, Sezione di Pisa, 56100 Pisa, Italy. Abstract arxiv:hep-lat/9704002v1 6
More informationDirected by: Prof. Yuanning Gao, IHEP, Tsinghua University Prof. Aurelio Bay, LPHE, EPFL
Masters Thesis in High Energy Physics Directed by: Prof. Yuanning Gao, IHEP, Tsinghua University Prof. Aurelio Bay, LPHE, EPFL 1 Study for CP-violation in the ψ π + π J/ψ transition Vincent Fave July 18,
More informationInterstellar Cosmic-Ray Spectrum from Gamma Rays and Synchrotron
Interstellar Cosmic-Ray Spectrum from Gamma Rays and Synchrotron Chuck Naval Research Laboratory, Washington, DC charles.dermer@nrl.navy.mil Andy Strong Max-Planck-Institut für extraterrestrische Physik,
More informationElectron-Muon Ranger (EMR)
Electron-Muon Ranger (EMR) Ruslan Asfandiyarov MICE Video Conference April 11, 2013 Construction Construction quarter of the detector completed (12 planes) every plane tested (LED / Camera / image analysis)
More informationπ 0 γγ calibration Savrina Daria, ITEP, Moscow SINP MSU, Moscow Victor Egorychev, ITEP, Moscow Ivan Belyaev
π 0 γγ calibration Savrina Daria, ITEP, Moscow SINP MSU, Moscow Ivan Belyaev Victor Egorychev, ITEP, Moscow Loose cuts for π 0 selection One of the ways to improve the calibration procedure is to increase
More informationThe Mainz LXe TPC MC simulations for a Compton scattering experiment
The Mainz LXe TPC MC simulations for a Compton scattering experiment Pierre Sissol Johannes Gutenberg Universität Mainz 12 November 2012 1 / 24 Outline 1 Dark Matter 2 Principle of a dual-phase LXe TPC
More informationSelected Topics in Elementary Particle Physics ( Haupt-Seminar )
Selected Topics in Elementary Particle Physics ( Haupt-Seminar ) Paola Avella, Veronika Chobanova, Luigi Li Gioi, Christian Kiesling, Hans-Günther Moser, Martin Ritter, Pit Vanhoefer Time: Do, 12 ct -14
More informationOverview of Common Analysis Tools
Overview of Common Analysis Tools D0 Workshop Michigan State Univesity June 19, 2007 H. Greenlee 1 Outline Standard Datasets. Framework (tmb) object id. and efficiency tools. CAF object id. and efficiency
More informationPart 2: Analysis of Relationship Between Two Variables
Part 2: Analysis of Relationship Between Two Variables Linear Regression Linear correlation Significance Tests Multiple regression Linear Regression Y = a X + b Dependent Variable Independent Variable
More informationStudy of electron cloud at MI and slip stacking process simulation
Study of electron cloud at MI and slip stacking process simulation Alexandr S. Valkovich Purpose 1.Understand the slip stacking process which happens in the Main Injector. 2. Calculation of bunch distortion
More informationProgress in understanding quarkonium polarization measurements
1 Progress in understanding quarkonium polarization measurements 1. Why it is essential that we approach the measurement of polarization as a multidimensional problem: we must not average out information!.
More informationWhy the high lying glueball does not mix with the neighbouring f 0. Abstract
Why the high lying glueball does not mix with the neighbouring f 0. L. Ya. Glozman Institute for Theoretical Physics, University of Graz, Universitätsplatz 5, A-800 Graz, Austria Abstract Chiral symmetry
More informationACCELERATORS AND MEDICAL PHYSICS 2
ACCELERATORS AND MEDICAL PHYSICS 2 Ugo Amaldi University of Milano Bicocca and TERA Foundation EPFL 2-28.10.10 - U. Amaldi 1 The icone of radiation therapy Radiation beam in matter EPFL 2-28.10.10 - U.
More information