SPRACE Analysis Prospects Srgio Lietti Pedro Mercadante Srgio

SPRACE Analysis Prospects Sérgio Lietti, Pedro Mercadante, Sérgio Novaes, Thiago Tomei (UNESP) Eduardo Gregores (UFABC)

Summary • SPRACE Team • Universal Extra Dimensions – Theory – Analysis at DZero • CMS Involvement 7/Feb/2007 P. Mercadante 2

São Paulo Regional Analysis Center – The Group • Sérgio Novaes • Eduardo Gregores • Sérgio Lietti • Pedro Mercadante • Gustavo Pavani • Rogerio Iope • Marco Dias • Thiago Tomei • Wescley Teixeira Professor Postdoc System Manager Graduated Student Undergraduate – DZero Experiment (since 1999). • Hardware: Forward Proton Detector • Analysis: Search for Extra Dimensions. • Monte Carlo production: > 10 Million event • Data Reprocessing – CMS Experiment (since 2005). • OSG active site since 2005 • LCG computing element as a CMS T 2 7/Feb/2007 P. Mercadante – Cluster • 90 Dual/Duo Xeon (240 processors) • Computing Power: 310 k. Si 2 k • Storage Capacity : 20 TB – Network Connection • Direct Gigabit connection with USA (WHREN-Lila) • Direct Gigabit connection with HEP clusters at Rio de Janeiro (Giga) • Optical connection for network test bed (Ultra. Light/Kyatera) – Grid Computing Initiatives • Distributed Organization for Scientific Analysis and Research (DOSAR) site • Operational SAMGrid site • Open Science Grid member site • Operating as a CMS Tier 2 3

SPRACE Cluster Phase 1 Phase 2 7/Feb/2007 P. Mercadante 4

SAMGrid 7/Feb/2007 P. Mercadante 5

OSG VO CDF i 2 u 2 CMS i. VDGL DES LIGO DOSAR mariachi DZero MIS Fermilab nano. HUB f. MRI NWICG GADU Ops geant 4 OSG GLOW OSGEDU GRASE SDSS Grid. Chem STAR Grid. Ex USATLAS GROW 7/Feb/2007 P. Mercadante 6

Background on Phenomenology • Phenomenology topics: – – – – Higgs boson search Anomalous couplings SUSY Extra Dimension Excited States Leptoquarks QCD SFN, SML SFN, PGM, EMG PGM, SML EMG, SFN, PGM EMG • Beginning an analysis with real data at DZero – Universal Extra Dimensions 7/Feb/2007 PGM, SML & Greg Landsberg P. Mercadante 7

Universal Extra Dimensions • Many theoretical reasons for studying UEDs (electroweak symmetry breaking, proton decay, the number of generations, neutrino masses, etc. ) • All SM fields are free to propagate in EDs with the size Rc = 1/Mc ~ 1 Te. V-1 • Instead of chiral doublets and singlets, model contains vector-like quarks and leptons • All particles acquire Kaluza-Klein (KK) modes with masses Mn 2 = M 02 + n 2/Rc 2, n = 0, 1, 2, … • If KK parity is conserved at tree level, KK-excitations are produced in pairs, similar to SUSY particles • Current limits dominated by precision electroweak measurements are low (Mc = 1/Rc ~ 300 Ge. V) 7/Feb/2007 P. Mercadante 8

Phenomenology • Simplest scenario, all SM fields propagating in a single extra dimension [Cheng, Matchev, Schmaltz, PRD 66, 056006 (2002)] • One would expect large clusters of nearly degenerate states with mass around 1/RC, 2/RC, …. • However, as radiative corrections tend to be large, the KK excitation mass spectrum resembles that of SUSY! (Cheng, Feng, Matchev, Schmaltz) • The pair production of 1 -level (KK) modes of quarks and leptons could be tested at Tevatron 7/Feb/2007 One-loop corrected mass of 1 -level (kk) modes Q, L (q, l) are SU(2) doublets (singlets) and contain both chiralities P. Mercadante 9

Signal at Tevatron and LHC • Production: PP Q 1 Q 1 W 1 W 1, W 1 Z 1, Z 1 Z 1 + jets 2 -4 leptons + ET missing • 4 leptons Signal: – Low efficiency – Soft Leptons ( Degenerescency) • Much more promising channels • 2 (3) leptons + ET missing 7/Feb/2007 P. Mercadante Cheng, Matchev, Schmaltz, PRD 66, 056006 (2002) 10

Pythia UED QQ TOTAL G Q W L QG GG Pair production of Q 1 Q 1 cross section for several initial states as a function of scale R First excited states masses as a function of scale R http: //wwwlapp. in 2 p 3. fr/~przys/Pythia. UED. html 7/Feb/2007 P. Mercadante 11

Expected Cross Section for Signal and Background at Tevatron § Isolation: PT < 2 Ge. V in 0. 4 cone Nl ZZ WZ UED (200) UED (300) 0 846 1775 22367 953 § Pt jet 1 48 504 6033 242 § Etot 2 94 108 892 40 § lepton invariant mass 3 2 28 9 0. 93 4 3 0 0 0. 03 2 ss 6 34 § Cuts on § Missing Et § Njets § Pt lep 345 14 Cross section for each channel (fb) 7/Feb/2007 P. Mercadante 12

Distributions and cuts • Two or more jets 7/Feb/2007 • PTlepton < 30 Ge. V • Minv(l+ l-) < 60 Ge. V WZ ZZ WZ WZ ZZ ZZ P. Mercadante 13

Expected Reach • Cross Sections for 2 ss leptons signal and bg. • Cuts are optmized for 2 fb-1 (5 evt) R-1 = 300 Ge. V. • After cuts bg is negligible. Reach is rate limited. 7/Feb/2007 P. Mercadante 14

D 0 Full Simulation (2 ss muons) Background (fb) Total Events 2 2 ss (fb) W 1. 82 x 106 4, 026, 329 255 177 31. 2 WZ inc 2. 41 x 103 305, 500 4, 662 619 2. 22 ZZ 4 1. 22 25, 250 19, 951 16, 019 0. 35 ZZ 2 e 2 2. 44 25, 000 11, 242 180 0. 0054 ZZ inc 994 100, 250 2, 926 95 0. 38 • The cross section is taken from the Pythia X BR. • We include the weight from MC efficiency calculations (last column) • Comparison with the phenomenological study: • Factor of 3 lower cross section due to the efficiency. • Expect similar factor for the signal. • The second muon in W Bg is mainly a fake muon. 7/Feb/2007 P. Mercadante 15

Some Plots Missing ET for ZZ bg (big tail is due to fail to reconstruct muuons) inc 2 e 2µ 4µ PT of second muon W WZ 7/Feb/2007 P. Mercadante 16

More on mising Et for muons Missing Et for Z 4 in several channels Sum 4 3 2 4 Muon Et sum for Z 4 in several channels from MC generator level (dotted lines) and full Dzero simulation (full lines) 7/Feb/2007 P. Mercadante 3 2 17

Working on • Full Dzero simulation for the signal – We compiled our private UED Pythia in clued 0. – Starting to use mcpp_gen and d 0_mcpp_gen packages to perform the full simulation. • Electron + muon signal • QCD background: estimate from data. 7/Feb/2007 P. Mercadante 18

UED at LHC • Monte Carlo UED in the CMS Framework – Pythia UED – Madgraph ? • Much higher cross section – – 7/Feb/2007 Allows for higher mass scale reach Is it possible to distinguish the signal from SUSY? Reconstruct some mass? Second excited state? Single production? P. Mercadante 19

Prospect for CMS • Open issue – – Get involved in UED Other topics from new Physics We are open for sugestion/collaboration Collaborate to physics object group • Thiago Tomei is going to CERN for one year – Starting second semester 2007 – Thesis topic in NP 7/Feb/2007 P. Mercadante 20