Diffractive Dijet Production Issues with Analysis Hardeep Bansil Birmingham Weekly ATLAS Meeting 15/09/2011.

Slides:

Advertisements

Similar presentations

Low x meeting, Sinai Alice Valkárová on behalf of H1 collaboration LOW x meeting 2005, Sinaia H1 measurements of the structure of diffraction.

Advertisements

CERN March 2004HERA and the LHC: Diffractive Gap Probability K. Goulianos1 HERA and the LHC K. Goulianos, The Rockefeller University CERN March.

1 Pierre Marage Univ. Libre de Bruxelles On behalf of the H1 and ZEUS collaborations Diffraction at HERA CIPANP 2006 Puerto-Rico 29/5-4/6/2006.

DIFFRACTION NEWS FROM CDF Konstantin Goulianos The Rockefeller University Otranto (Lecce), Italy.

Brazil 31 Mar – 2 Apr 2004 Diffraction: from HERA & Tevatron to LHC K. Goulianos1 Diffraction: from HERA & Tevatron to LHC K. Goulianos, The Rockefeller.

K. Goulianos The Rockefeller University EDS May 2005 Chateau de Blois, France Twenty Years of Diffraction at the Tevatron

Diffractive x-sections and event final states at the LHC Konstantin Goulianos The Rockefeller University / Diffraction Day.

Manchester Dec 2003 Diffraction from HERA and Tevatron to LHCK. Goulianos1 Konstantin Goulianos The Rockefeller University Workshop on physics with.

19-24 May 2003K. Goulianos, CIPANP Konstantin Goulianos The Rockefeller University & The CDF Collaboration CIPANP-2003, New York City, May.

DIFFRACTION RESULTS FROM CDF XIX International Workshop on Deep-Inelastic Scattering and Related Subjects (DIS 2011) April 11-15, 2011 Newport News, VA.

Hard Diffraction at HERA and the Tevatron Introduction QCD Factorization Diffractive Structure HERA Diffractive Dijets and VM HERA.

September 17-20, 2003.Kenichi Hatakeyama1 Soft Double Pomeron Exchange in CDF Run I Kenichi Hatakeyama The Rockefeller University for the CDF Collaboration.

ISMD July – 1 August 2004 Sonoma County, California, USA DIFFRACTION FROM THE DEEP SEA Konstantin Goulianos The Rockefeller University.

Diffraction at CDF 12th International Conference on Elastic and Diffractive Scattering Forward Physics and QCD – Blois2007 Hamburg, Germany, May.

Diffractive W/Z & Exclusive CDF II DIS 2008, 7-11 April 2008, University College London XVI International Workshop on Deep-Inelastic Scattering and.

Diffraction at CDF and Universality of Diffractive Factorization Breaking Konstantin Goulianos The Rockefeller University

Recent Results on Diffraction and Exclusive Production from CDF Christina Mesropian The Rockefeller University.

25 th of October 2007Meeting on Diffraction and Forward Physics at HERA and the LHC, Antwerpen 1 Factorization breaking in diffraction at HERA? Alice Valkárová.

23-28 June 2003K. Goulianos, Blois Workshop, Helsinki, Finland1 Konstantin Goulianos The Rockefeller University & The CDF Collaboration Xth Blois Workshop.

The Diffractive Structure Function: ξ dependence Christina Mesropian The Rockefeller University.

M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, Blessing of Run II Diffractive Results Introduction Data Selection.

Diffractive and total pp cross sections at the LHC and beyond Konstantin Goulianos The Rockefeller University

Diffractive W and Z Production at Tevatron Konstantin Goulianos The Rockefeller University and the CDF collaboration Moriond QCD and High Energy Interactions.

Diffractive Higgs Production at the Tevatron and LHC Do we all disagree, and, if so, why? How sensitive are the predictions to the.

Konstantin Goulianos The Rockefeller University Diffraction at CDF and at the LHC LOW X MEETING: HOTEL VILLA SORRISO, ISCHIA ISLAND, ITALY, September 8-13.

Paul Laycock University of Liverpool BLOIS 2007 Diffractive PDFs.

Evidence for high mass exclusive dijet production in the D0 experiment Zdenek Hubacek Czech Technical University in Prague (on behalf of D0 Collaboration)

ATLAS UK Physics meeting

Predictions of Diffractive, Elastic, Total, and Total-Inelastic pp Cross Sections vs LHC Measurements Konstantin Goulianos The Rockefeller University DIS-2013,

1 Jets in diffraction and factorization at HERA Alice Valkárová Charles University, Prague On behalf of H1 and ZEUS collaborations.

W + /W - and l + /l - A Means to investigate PDFs T. Schörner-Sadenius, G. Steinbrück Hamburg University HERA-LHC Workshop, CERN, October 2004.

K. Goulianos The Rockefeller University (Representing the CDF Collaboration) DIS April – 1 May Madison, Wisconsin Update on CDF Results on Diffraction.

K. Goulianos CDF RESULTS ON DIFFRACTION AND EXCLUSIVE PRODUCTION Konstantin Goulianos 14th Workshop on Elastic and Diffractive Scattering (EDS Blois Workshop.

LISHEP Rio de Janeiro1 Factorization in diffraction Alice Valkárová Charles University, Prague On behalf of H1 and ZEUS collaborations.

Update on Diffractive Dijet Production Search Hardeep Bansil University of Birmingham Birmingham ATLAS Weekly Meeting 13/09/2012.

Diffractive Dijet Production Hardeep Bansil University of Birmingham SM Soft QCD topical meeting: Diffraction and Forward Detectors 24/05/2011.

Update on Diffractive Dijet Production Search Hardeep Bansil University of Birmingham Birmingham ATLAS Weekly Meeting 24/01/2013.

Update on Diffractive Dijets Analysis Hardeep Bansil Birmingham ATLAS Weekly Meeting 10/04/2014.

Hardeep Bansil, Oldrich Kepka, Vlastimil Kus, Paul Newman, Marek Tasevsky Workshop on Diffractive Analyses with ALFA 09/10/2012 Diffractive analyses with.

K. Goulianos The Rockefeller University Renormalized Diffractive Parton Densities and Exclusive Production Diffraction 2006 Milos island, Greece, 5-10.

Hadron Structure 2009 Factorisation in diffraction Alice Valkárová Charles University, Prague Representing H1 and ZEUS experiments Hadron structure.

Searches for Diffractive Dijet Production Hardeep Bansil University of Birmingham SM Soft QCD meeting 24/10/2011.

New results on diffractive t-distributions from CDF Konstantin Goulianos The Rockefeller University (for the CDF Collaboration) DIS-2012 DIS-2012, Bonn,

Diffractive Dijet Production with 2010 data Hardeep Bansil (1), Oldřich Kepka (2), Vlastimil Kůs (2), Paul Newman (1), Marek Taševský (2) (1) University.

1 Diffractive dijets at HERA Alice Valkárová Charles University, Prague Representing H1 and ZEUS experiments.

Issues with cluster calibration + selection cuts for TrigEgamma note Hardeep Bansil University of Birmingham Birmingham ATLAS Weekly Meeting 12/08/2010.

Update on Diffractive Dijet Production Search Hardeep Bansil University of Birmingham Soft QCD WG Meeting 29/04/2013.

Isabell-A. Melzer-Pellmann DIS 2007 Charm production in diffractive DIS and PHP at ZEUS Charm production in diffractive DIS and PHP at ZEUS Isabell-Alissandra.

CDF RESULTS ON DIFFRACTION and EXCLUSIVE PRODUCTION Konstantin Goulianos 14th Workshop on Elastic and Diffractive Scattering (EDS Blois Workshop ) Frontiers.

Update on Diffractive Dijets Analysis Hardeep Bansil University of Birmingham Soft QCD / Diffraction WG Meeting 31/03/2014.

Update on Diffractive Dijets Hardeep Bansil University of Birmingham 12/07/2013.

17-20 September 2003K. Goulianos, Small x and Diffraction, Fermilab1 Konstantin Goulianos The Rockefeller University Small x and Diffraction

Costas Foudas, Imperial College, Jet Production at High Transverse Energies at HERA Underline: Costas Foudas Imperial College

Update on Diffractive Dijet Production Search Hardeep Bansil University of Birmingham 23/07/2012.

Update on Diffractive Dijets Analysis Hardeep Bansil University of Birmingham Soft QCD / Diffraction WG Meeting 28/10/2013.

Update on Diffractive Dijets Search Hardeep Bansil University of Birmingham SM Soft QCD meeting 12/12/2011.

Update on Diffractive Dijet Production Search Hardeep Bansil University of Birmingham Birmingham ATLAS Weekly Meeting 08/12/2011.

Update on Diffractive Dijets Analysis Hardeep Bansil University of Birmingham 06/11/2013.

Improving ATLAS hard diffraction measurements with the STEP award Hardeep Bansil University of Birmingham 18/10/2013.

Diffractive Dijet Production: Update on analysis issues Hardeep Bansil Birmingham Weekly ATLAS Meeting 22/09/2011.

Update on Diffractive Dijets Analysis Hardeep Bansil University of Birmingham Soft QCD / Diffraction WG Meeting 27/01/2014.

ATLAS results on diffraction and exclusive production

ATLAS results on diffraction and exclusive production

Aspects of Diffraction at the Tevatron

Diffraction in ep collisions

Trigger  Detectors at 420m can be included in the HLT

DIFFRACTIVE DIJET PRODUCTION AT CDF

CDF RESULTS ON DIFFRACTION AND EXCLUSIVE PRODUCTION

Single Diffractive Higgs Production at the LHC *

Diffractive PDF fits and factorisation tests at HERA

Presentation transcript:

Diffractive Dijet Production Issues with Analysis Hardeep Bansil Birmingham Weekly ATLAS Meeting 15/09/2011

Contents Theory / Motivation Current issues Next steps 2

Diffractive dijets Look for single diffractive events (pp  pX) – Involve a rapidity gap due to colourless exchange with vacuum quantum numbers “pomeron” Then look for dijet system within X – Hard diffraction Sensitive to the diffractive structure function (dPDF) of the proton Studied at HERA and Tevatron – At Tevatron, ratio of yields of SD to inclusive dijets ~ 1% – Likely to be smaller than this at LHC 3

Motivation Understand the structure of the diffractive exchange by comparison with predictions from electron-proton data and be able to get a measure of F D jj Measure the ratio of the single diffractive to inclusive dijet events Gap Survival Probability – the chance of the gap between the intact proton and diffractive system being lost due to scattering (affects measured structure function e.g. Tevatron results a factor of 10 smaller than H1 predictions) 4 Rescatter with p? (ξ)(ξ)

Current issues No proper plots today …... for various reasons 5

Analysis Bottleneck Running over 2010 periods A&B (∫L dt = 8.75 nb -1, 75mil events) Grid running fast enough (only some slow sites) Major bottleneck in running locally over ntuples  now taking over 2 days – FAR TOO LONG – ISSUES WITH NTUPLE? – ISSUES WITH READING DISK? Tried selecting only a few branches to load per event Looking into skimming events (1 jet with > 10 GeV no big difference – trying with 20 GeV) Possibly try multithreading (PROOF)? 6 Running jobs on grid  get ntuples (1/1.5 days) Running over ntuples on batch server to get useful histograms (2+ days) Run over histos to get final plots (5 minutes)

Monte Carlo Generators Currently using Pomwig LO generator Generated QCD 2  2 process within diffractive system in different p T ranges (8-17, 17-35, 35-70, 70+ GeV) – Single Diffractive “SD” (system dissociating in ±z direction) – Double Pomeron Exchange “DPE” won’t be needed Central Diffractive, not Double Diffractive – scale SD Will request to get official Monte Carlo production done – Pomwig already validated so no need to directly compare with another generator Rapgap possible – Working with version modified to output in HepMC format – Currently getting help from Rivet authors to get this running Herwig++ samples available soon – Prague group really pushing for this generator Issues with storing ESDs on Grid – Current ESD samples only safe until end of year 7

AntiKt η confusion Analysis uses both AntiKt R=0.4 and R=0.6 jets Using MinBias data sample, ask for forward gap (∆η F >2.0) with jet 1 > 26 GeV, jet 2 > 20 GeV, jets not within gap AntiKt6 – before and after gap cuts, see a (approximately) symmetric η distribution for jet 1, similar for jet 2 8 Before forward gap cuts After forward gap cuts

AntiKt η confusion Analysis uses both AntiKt R=0.4 and R=0.6 jets Using MinBias data sample, ask for forward gap (∆η F >2.0) with jet 1 > 26 GeV, jet 2 > 20 GeV, jets not within gap AntiKt4 – fewer events passing cuts with smaller jets See a big spike between 0<η<1 in both cases, after gap cuts gets even worse  investigate further but not from allocating variable incorrectly 9 Before forward gap cuts After forward gap cuts

Next steps Fix issues Make plots 10