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RENORM Diffractive Predictions Extended to Higher LHC and Future Accelerator Energies Konstantin Goulianos http://physics.rockefeller.edu/dino/my.html 1LHC-WG-2015 RENORM Diffractive Predictions Extended K.Goulianos http://workshops.ift.uam-csic.es/LHCFPWG2015
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Basic and combined diffractive processes CONTENTS RENORM Diffractive Predictions Extended K.Goulianos 2LHC-WG-2015 Diffraction SD1 p 1 p 2 p 1 +gap+X 2 Single Diffraction / Dissociation –1 SD2p 1 p 2 X 1 +gap+p 2 Single Diffraction / Dissociation - 2 DDp 1 p 2 X 1 +gap+X 2 Double Diffraction / Double Dissociation CD/DPEp 1 p 2 gap+X+gap Central Diffraction / Double Pomeron Exchange Renormalization Unitarization RENORM Model Triple-Pomeron Coupling Total Cross Section RENORM Predictions Confirmed RENORM Predictions Extended References MBR MC Simulation in PYTHIA8, KG & R. Ciesielski, http://arxiv.org/abs/1205.1446 Previous talk (predictions compared to preliminary CMS results) MIAMI 2014 (slides) https://cgc.physics.miami.edu/Miami2014/Goulianos2014.pdf (17-23 Dec 2014)https://cgc.physics.miami.edu/Miami2014/Goulianos2014.pdf Present talk (predictions compared to final CMS results) CMS Soft Diffraction at 7 TeV: http://arxiv.org/format/1503.08689v1 (30 Mar 2015)http://arxiv.org/format/1503.08689v1
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Basic and combined diffractive processes RENORM: Basic and Combined Diffractive Processes 4-gap diffractive process-Snowmass 2001- http://arxiv.org/pdf/hep-ph/0110240http://arxiv.org/pdf/hep-ph/0110240 gap SD DD RENORM Diffractive Predictions Extended K.Goulianos 3LHC-WG-2015 BASIC COMBINED particles DD SD Cross sections analytically expressed in arXiv below:
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KG-PLB 358, 379 (1995) Regge Theory: Values of s o & g PPP ? Parameters: s 0, s 0 ' and g(t) set s 0 ' = s 0 (universal Pomeron) determine s 0 and g PPP – how? (t)= (0)+ ′t (0)=1+ RENORM Diffractive Predictions Extended K.Goulianos 4LHC-WG-2015 http://www.sciencedirect.com/science/article/pii/037026939501023J
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A complicatiion… Unitarity! Theoretical Complication: Unitarity! sd grows faster than t as s increases * unitarity violation at high s (also true for partial x-sections in impact parameter space) the unitarity limit is already reached at √s ~ 2 TeV ! need unitarization * similarly for (d el /dt) t=0 w.r.t. t but this is handled differently in RENORM RENORM predictions for diffraction at LHC confirmed RENORM Diffractive Predictions Extended K.Goulianos 5LHC-WG-2015
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Factor of ~8 (~5) suppression at √s = 1800 (540) GeV Diffractive x-section suppressed relative to Regge prediction as √s increases KG, PLB 358, 379 (1995) 1800 GeV 540 GeV M ,t,t p p p’ √s=22 GeV RENORMALIZATION Regge FACTORIZATION BREAKING IN SOFT DIFFRACTION CDFCDF Interpret flux as gap formation probability that saturates when it reaches unity RENORM Diffractive Predictions Extended K.Goulianos 6LHC-WG-2015 http://www.sciencedirect.com/science/article/pii/037026939501023J
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Gap probability (re)normalize it to unity Single Diffraction Renormalized - 1 2 independent variables: t color factor gap probability sub-energy x-section KG CORFU-2001: http://arxiv.org/abs/hep-ph/0203141 RENORM Diffractive Predictions Extended K.Goulianos 7LHC-WG-2015
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Single Diffraction Renormalized - 2 color factor Experimentally: KG&JM, PRD 59 (114017) 1999 QCD: RENORM Diffractive Predictions Extended K.Goulianos 8LHC-WG-2015
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Single Diffraction Renormalized - 3 set to unity determines s o RENORM Diffractive Predictions Extended K.Goulianos 9LHC-WG-2015
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M2 distribution: data M 2 - Distribution: Data KG&JM, PRD 59 (1999) 114017 factorization breaks down to ensure M 2 scaling Regge 1 http://physics.rockefeller.edu /publications.html d dM 2 | t=-0.05 ~ independent of s over 6 orders of magnitude ! data RENORM Diffractive Predictions Extended K.Goulianos 10LHC-WG-2015 http://physics.rockefeller.edu/publications.html
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Scale s 0 and PPP Coupling Two free parameters: s o and g PPP Obtain product g PPP s o from SD Renormalized Pomeron flux determines s o Get unique solution for g PPP Pomeron-proton x-section Pomeron flux: interpret it as gap probability set to unity: determines g PPP and s 0 KG, PLB 358 (1995) 379 RENORM Diffractive Predictions Extended K.Goulianos 11LHC-WG-2015 http://www.sciencedirect.com/science/article/pii/037026939501023J
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DD at CDF Renor’d gap probabilityx-section RENORM Diffractive Predictions Extended K.Goulianos 12LHC-WG-2015 Regge x-section divided by integrated gap prob. http://physics.rockefeller.edu/publications.html
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SDD at CDF Excellent agreement between data and MBR (MinBiasRockefeller) MC RENORM Diffractive Predictions Extended K.Goulianos 13LHC-WG-2015 http://physics.rockefeller.edu/publications.html
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CD/DPE at CDF Excellent agreement between data and MBR based MC Confirmation that both low and high mass x-sections are correctly implemented RENORM Diffractive Predictions Extended K.Goulianos 14LHC-WG-2015 http://physics.rockefeller.edu/publications.html
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RENORM Difractive Cross Sections 1 =0.9, 2 =0.1, b 1 =4.6 GeV -2, b 2 =0.6 GeV -2, s′=s e - y, =0.17, 2 (0)= 0, s 0 =1 GeV 2, 0 =2.82 mb or 7.25 GeV -2 RENORM Diffractive Predictions Extended K.Goulianos 15LHC-WG-2015
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Total, Elastic, and Inelastic x-Sections GeV 2 KG Moriond 2011, arXiv:1105.1916 el p±p = tot p±p ×( el tot ) p±p, with el tot from CMG small extrapol. from 1.8 to 7 and up to 50 TeV ) CMG RENORM Diffractive Predictions Extended K.Goulianos 16LHC-WG-2015
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The total x-section √s F =22 GeV 98 ± 8 mb at 7 TeV 109 ±12 mb at 14 TeV Main error is due to s 0 RENORM Diffractive Predictions Extended K.Goulianos 17LHC-WG-2015
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How to Reduce Uncertainty in s 0 glue-ball-like object “superball” mass 1.9 GeV m s 2 = 3.7 GeV agrees with RENORM s o =3.7 Error in s 0 can be reduced by factor ~4 from a fit to these data reduces error in t RENORM Diffractive Predictions Extended K.Goulianos 18LHC-WG-2015
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TOTEM (2012) vs PYTHIA8-MBR inel 7 TeV = 72.9 ±1.5 mb inel 8 TeV = 74.7 ±1.7 mb TOTEM, G. Latino talk at MPI@LHC, CERN 2012 MBR: 71.1±5 mb superball ±1.2 mb RENORM: 72.3±1.2 mb RENORM: 71.1±1.2 mb RENORM Diffractive Predictions Extended K.Goulianos 19LHC-WG-2015
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ATLAS - in Diffraction 2014 (Talk by Marek Taševský, slide#19) RENORM Diffractive Predictions Extended K.Goulianos 20LHC-WG-2015 RENORM: 98.0±1.2 mb http://www.cs.infn.it/en/web/external_community/home 19
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The CMS Detector RENORM Diffractive Predictions Extended K.Goulianos 21LHC-WG-2015 CASTOR forward calorimeter important for separating SD from DD contributions DD SD ND CD
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CMS Data vs MC Models (2015)-1 RENORM Diffractive Predictions Extended K.Goulianos 22LHC-WG-2015 SD dominated dataDD dominated data Error bars are dominated by systematics DD data scaled downward by 15% (within MBR and CDF data errors)
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CMS Data vs MC Models (2015) -2 RENORM Diffractive Predictions Extended K.Goulianos 23LHC-WG-2015 Central -gap x-sections (DD dominated) .P8-MBR provides the best fit to data .All above models too low at small
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SD/DD Extrapolations to x ≤ 0.05 vs MC Models RENORM Diffractive Predictions Extended K.Goulianos 24LHC-WG-2015
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p T Distr’s of MCs vs Pythia8 Tuned to MBR COLUMNS Mass Regions Low5.5<MX<10 GeV Med.32<MX<56 GeV High176<MX<316 GeV ROWS MC Models PYTHIA8-MBR PYTHIA8-4C PYTHIA6-Z2* PHOJET QGSJET-II-03 QGSJET-04 EPOS-LHC CONCLUSION PYTHIA8-MBR agrees best with the reference model and is used by CMS in extrapolating to the unmeasured regions. Pythia8 tuned to MBR RENORM Diffractive Predictions Extended K.Goulianos 25LHC-WG-2015
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Charged Mult’s vs MC Model – 3 Mass Regions Pythia8 parameters tuned to reproduce multiplicities of modified gamma distribution (MGD) KG, PLB 193, 151 (1987 ) Mass Regions Low5.5<MX<10 GeV Med.32<MX<56 GeV High176<MX<316 GeV RENORM Diffractive Predictions Extended K.Goulianos 26LHC-WG-2015 0 < p T < 1.4 GeV CERN ISR 52.6 GeV SppS 540 GeV - Diffractive data vs MGD CERN ISR & SppS w/MGD fit - http://www.sciencedirect.com/science/article/pii/0370269387904746
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Pythia8-MBR Hadronization Tune 27 PYTHIA8 default Pp (s) expected from Regge phenomenology for s 0 =1 GeV 2 and DL t-dependence. Red line:-best fit to multiplicity distributions. (in bins of Mx, fits to higher tails only, default pT spectra) good description of low multiplicity tails R. Ciesielski, “Status of diffractive models”, CTEQ Workshop 2013 Diffraction: tune SigmaPomP Diffraction: QuarkNorm/Power parameter RENORM Diffractive Predictions Extended K.Goulianos 27LHC-WG-2015
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SD and DD x-Sections vs Models Includes ND background RENORM Diffractive Predictions Extended K.Goulianos 28LHC-WG-2015 Single Diffraction Double Diffraction
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CMS vs MC & ATLAS RENORM Diffractive Predictions Extended K.Goulianos 29LHC-WG-2015 Uncorrected Δη F distribution vs MCs Stable-particle x-sections for pT>200 MeV and | |<4.7 compared to the ATLAS 2012 result similar result
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Monte Carlo Algorithm - Nesting y'cy'c Profile of a pp Inelastic Collision y‘ < y' min hadronize y′ > y' min generate central gap repeat until y' < y' min ln s′ = y′ evolve every cluster similarly gap no gap final state of MC w /no-gaps t gap t t t1t1 t2t2 RENORM Diffractive Predictions Extended K.Goulianos 30LHC-WG-2015
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SUMMARY Introduction Diffractive cross sections: basic: SD1,SD2, DD, CD (DPE) combined: multigap x-sections ND no diffractive gaps: this is the only final state to be tuned Monte Carlo strategy for the LHC – “nesting” derived from ND and QCD color factors Thank you for your attention! Special thanks to Robert A. Ciesielski, my collaborator in the PYTHIA8-MBR project Warm thanks to my CDF and CMS colleagues, and to Office of Science of DOE RENORM Diffractive Predictions Extended K.Goulianos 31LHC-WG-2015
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BACKUP RENORM Diffractive Predictions Extended K.Goulianos 32LHC-WG-2015
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Saturation at Low Q 2 and Small-x figure from a talk by Edmond Iancu RENORM Diffractive Predictions Extended K.Goulianos 33LHC-WG-2015
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