Download presentation
Presentation is loading. Please wait.
Published byLinda Pitts Modified over 9 years ago
1
Review of RENORM Diffractive Predictions for LHC up to 8 TeV and Extension to 13 TeV Konstantin Goulianos http://physics.rockefeller.edu/dino/my.html 1DIS-2015 Dallas RENORM Diffractive Predictions for LHC K.Goulianos GAP http://www.dis2015.org
2
Basic and combined diffractive processes CONTENTS RENORM Diffractive Predictions for LHC K.Goulianos 2DIS-2015 Dallas 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 (RENORM diffractive predictions extended to higher LHC and future accelerator energies) – similar to present talk LHCFPWG 2015 Madrid (slides) http://workshops.ift.uam-csic.es/LHCFPWG2015/program (21-25 Apr 2015) 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
3
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 for LHC K.Goulianos 3DIS-2015 Dallas BASIC COMBINED particles DD SD Cross sections analytically expressed in arXiv below:
4
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 for LHC K.Goulianos 4DIS-2015 Dallas http://www.sciencedirect.com/science/article/pii/037026939501023J
5
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 for LHC K.Goulianos 5DIS-2015 Dallas
6
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 for LHC K.Goulianos 6DIS-2015 Dallas http://www.sciencedirect.com/science/article/pii/037026939501023J
7
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 for LHC K.Goulianos 7DIS-2015 Dallas
8
Single Diffraction Renormalized - 2 color factor Experimentally: KG&JM, PRD 59 (114017) 1999 QCD: RENORM Diffractive Predictions for LHC K.Goulianos 8DIS-2015 Dallas
9
Single Diffraction Renormalized - 3 set to unity determines s o RENORM Diffractive Predictions for LHC K.Goulianos 9DIS-2015 Dallas
10
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 for LHC K.Goulianos 10DIS-2015 Dallas http://physics.rockefeller.edu/publications.html
11
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 for LHC K.Goulianos 11DIS-2015 Dallas http://www.sciencedirect.com/science/article/pii/037026939501023J
12
DD at CDF Renor’d gap probabilityx-section RENORM Diffractive Predictions for LHC K.Goulianos 12DIS-2015 Dallas Regge x-section divided by integrated gap prob. http://physics.rockefeller.edu/publications.html
13
SDD at CDF Excellent agreement between data and MBR (MinBiasRockefeller) MC RENORM Diffractive Predictions for LHC K.Goulianos 13DIS-2015 Dallas http://physics.rockefeller.edu/publications.html
14
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 for LHC K.Goulianos 14DIS-2015 Dallas http://physics.rockefeller.edu/publications.html
15
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 for LHC K.Goulianos 15DIS-2015 Dallas
16
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 for LHC K.Goulianos 16DIS-2015 Dallas
17
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 for LHC K.Goulianos 17DIS-2015 Dallas
18
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 for LHC K.Goulianos 18DIS-2015 Dallas
19
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 for LHC K.Goulianos 19DIS-2015 Dallas
20
ATLAS - in Diffraction 2014 (Talk by Marek Taševský, slide#19 RENORM Diffractive Predictions for LHC K.Goulianos 20DIS-2015 Dallas http://www.cs.infn.it/en/web/external_community/home 20 RENORM: 98.0±1.2 mb 19
21
The CMS Detector RENORM Diffractive Predictions for LHC K.Goulianos 21DIS-2015 Dallas CASTOR forward calorimeter important for separating SD from DD contributions DD SD ND CD
22
CMS Data vs MC Models (2015)-1 RENORM Diffractive Predictions for LHC K.Goulianos 22DIS-2015 Dallas SD dominated dataDD dominated data Error bars are dominated by systematics DD data scaled downward by 15% (within MBR and CDF data errors)
23
CMS Data vs MC Models (2015) -2 RENORM Diffractive Predictions for LHC K.Goulianos 23DIS-2015 Dallas Central -gap x-sections (DD dominated) .P8-MBR provides the best fit to data .All above models too low at small
24
SD/DD Extrapolations to x ≤ 0.05 vs MC Models RENORM Diffractive Predictions for LHC K.Goulianos 24DIS-2015 Dallas
25
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 for LHC K.Goulianos 25DIS-2015 Dallas
26
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 for LHC K.Goulianos 26DIS-2015 Dallas 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
27
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 for LHC K.Goulianos 27DIS-2015 Dallas
28
SD and DD x-Sections vs Models Includes ND background RENORM Diffractive Predictions for LHC K.Goulianos 28DIS-2015 Dallas Single Diffraction Double Diffraction
29
CMS vs MC & ATLAS RENORM Diffractive Predictions for LHC K.Goulianos 29DIS-2015 Dallas 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
30
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 for LHC K.Goulianos 30DIS-2015 Dallas
31
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 for LHC K.Goulianos 31DIS-2015 Dallas
32
BACKUP RENORM Diffractive Predictions for LHC K.Goulianos 32DIS-2015 Dallas
33
Saturation at Low Q 2 and Small-x figure from a talk by Edmond Iancu RENORM Diffractive Predictions for LHC K.Goulianos 33DIS-2015 Dallas
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.