JADE, H1, OPAL and ZEUS

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1 JADE, H1, OPAL and ZEUS Andrii Verbytskyi Annual Project Review, MPP, Munich, 18 December / 31

2 Intro Old experiments have a lot of interesting unexplored physics in the data. Sometimes good ideas/predictions are coming late. It is cheaper and faster to preserve than rebuild and re-run. Many official efforts claim to have data preservation activities, but few have dedicated manpower, results or even data. JADE, H1, OPAL and ZEUS / 31

3 Hadron calorimeters and return yoke Electromagnetic calorimeters Muon detectors OPAL Jet chamber Vertex chamber Microvertex detector y z θ ϕ x Forward detector Presampler Silicon tungsten luminometer Time of flight detector Solenoid and pressure vessel One of four big experiments at famous e + e collider (LEP-I), (LEP-II) collaborators. s = GeV data available for re-analysis. Z chambers OPAL members in MPP: S.Bethke, S.Kluth + (A.Verbytskyi). 3 / 31

4 Jet physics with OPAL Jets are the way to link partons to hadronic final state. Past: 3.OR.4.OR.5- jet FS, now 5 simultaneously. LHC jets for LEP/future e + e : SISCone and anti-k T. Modern NLO MC validation. Measurement of jet rates, R n = σ(e+ e n jets) parameters y or ǫ: y = min(e i,ej )(1 cosθ ij ) Evis SISCone ǫ = E cut /E vis for all. σ(e + e hadrons) vs. resolution for k T, y =1 cosr for anti-k T and 4 / 31

5 Colour correspondence of correlation coefficients or N/A Jet rates vs. y and ǫ at Z pole k T reproduces old results. SISCone and anti-k T are similar. Fraction 1. 1 OPAL Durham, s = 91 GeV R R3 R4 R5 OPAL SISCone, s = 91 GeV ǫ = 3.85% OPAL anti-kt, s = 91 GeV ǫ = 3.85% R R3 R4 R lg(y) R R y 1 1 y 1 1 y R Fraction 1. 1 OPAL Durham, s = 91 GeV R R3 R4 R5 OPAL SISCone, s = 91 GeV R=0.34 OPAL anti-kt, s = 91 GeV R= R ǫ, % ǫ, % ǫ, % Covariance matrix for every measurement. (anti-k t vs. y here). See A. Verbytskyi, Studies of correlations between measurements of jet observables, JINST 1 (017) no.04, P / 31

6 NLO MC jet rates Fraction Fraction OPAL Durham, s = 91 GeV R R3 R4 H M H P 3 1 OPAL Durham, s = 91 GeV R R3 R4 H P H M S L S C R_5 R_5 R_ ǫ, % y S L S C R_5 R_5 R_5 OPAL SISCone, s = 91 GeV ǫ = 3.85% 1 1 y OPAL SISCone, s = 91 GeV R= ǫ, % OPAL anti-kt, s = 91 GeV ǫ = 3.85% 1 1 y OPAL anti-kt, s = 91 GeV R= ǫ, % Modern NLO MC: S L : Sherpa./BlackHat, CSS shower, Lund hadronisation S C : Sherpa./BlackHat, CSS shower, cluster hadronisation H P : Herwig7.0, POWHEG matching, cluster hadronisation H M : Herwig7.0, MC@NLO matching, cluster hadronisation Good description at 91GeV, much worse for higher energies. k T is described best of all. 6 / 31

7 Hadronisation corrections vs. y and energy cut ǫ Hadronisation corrections are ratios of n-jet cross-sections at hadron and parton levels. Closest to unity for k T. Almost flat for higher energies. Fraction OPAL Durham, s = 91 GeV L C S S.5 S3 L S3 C S4 L S4 C OPAL SISCone, s = 91 GeV ǫ = 3.85% OPAL anti-kt, s = 91 GeV ǫ = 3.85% y 1 1 y 1 1 y Fraction OPAL Durham, s = 91 GeV L C S S.5 S3 L S3 C S4 L S4 C OPAL SISCone, s = 91 GeV R=0.34 OPAL anti-kt, s = 91 GeV R= ǫ, % ǫ, % ǫ, % Draft in the EB. Input for α s determination once published. 7 / 31

JADE@PETRA One of key experiments for QCD:

8 One of key experiments for QCD: discovery of gluon, α s measurements, data preserved at unique energy. The oldest and most successful Data Preservation effort! 8 / 31

9 JADE data preservation history 1986: End of data taking : First preservation effort: data transfer, software port to AIX4.3, interface to LEP-era MC programs : Physics 11 papers, O(40) conference talks, theses, JADE notes. 017: Second preservation effort Data is online; All software ported to 86_64; Modern compilers and Cmake; Virtualisation. Interface simulation and reconstruction to LHC-era MC programs (HepMC3). Documentation (computing notes) is online. MPP: S. Bethke, S. Kluth + (A.Verbytskyi). 9 / 31

Event display 003, AIX JADE as DP primer in collaboration with CERN IT.

10 Preserved JADE and (potential) usage examples JADE software compilation in virtual machine Event display 017, Linux/Mac Thrust MC detector level distribution in ROOT Ntuples. Event display 003, AIX JADE as DP primer in collaboration with CERN IT. Potential physics cases: QCD with modern theory. Validation of modern analysis techniques. Monte Carlo folding simulation is fast! / 31

11 Extra physics at e + e colliders Collaboration with ext. groups on usage of theory predictions, e.g. Z. Tulipant, A. Kardos and G. Somogyi, Energy energy correlation in electron positron annihilation at NNLL + NNLO accuracy, Eur. Phys. J. C 77 (017) no.11, 749 A. Banfi, H. McAslan, P. F. Monni and G. Zanderighi, The two-jet rate in e + e at next-to-next-to-leading-logarithmic order, Phys. Rev. Lett. 117 (016) no.17, / 31

12 e + e : in progress α s fits with EEC: Advanced theory A lot of data Modern MC Proper statistics + some solvable problems Hadr. corrections for 1/σtdΣ/dχ 1/σtdΣ/dχ 1/σtdΣ/dχ 0.6 JADE,Bartel:1984uc,.0GeV S L H G hadrons,.0gev, 43.5GeV H G partons,.0gev Fit of S L H A hadrons,.0gev S C H, 43.5GeV A partons,.0gev 0.4 Fit of S C H G, 43.5GeV Fit of H G H A, 43.5GeV 0.00 Fit of H A 0. 0 Fit range 1.00 Fit range χ χ CELLO,Behrend:198na, 34.0GeV OPAL,Acton:1991cu, 91.GeV NNLO+NNLL(logR) NNLO+NNLL(logR) NLO+NNLL(logR) NLO+NNLL(logR) 1/σtdΣ/dχ Fit range Fit range Theory/Data χ χ Theory/Data χ χ 1 / 31

ZEUS@HERA One of two big experiments at HERA. 7.

13 One of two big experiments at HERA. 7.5GeV e ± collided with p (460/575/80/90GeV ) widest spectrum of physics. 0.5fb 1 of data, 500M events. O(300) members while running, 113 authors now. 13 / 31

14 ZEUS data preservation and recent results Data, SW and documentation are stored in DESY&MPCDF. Software is virtualized in MPP. MC production with old/new generators is available in MPP. ZEUS members in MPP : I. Abt, H. Abramowicz, A. Caldwell and A. Verbytskyi. Recent papers: H. Abramowicz et al. [ZEUS Collaboration], Studies of the diffractive photoproduction of isolated photons at HERA, Phys. Rev. D 96 (017) no.3, H. Abramowicz et al. [ZEUS Collaboration], Further studies of isolated photon production with a jet in deep inelastic scattering at HERA, arxiv: [hep-ex] 14 / 31

15 Further studies of isolated photon production with a jet in deep inelastic scattering at HERA Prompt photons are the direct probe of perturbative process. Background: Signal: Measurement: 36 pb 1, < Q < 350 GeV. Cross-sections in bins of transverse jet or γ momenta/rapidity and angular distances in pairs e γ, e jet, jet γ. 15 / 31

16 Further studies of isolated photon production with a jet in deep inelastic scattering at HERA x γ /x p are fractions of the exchanged-photon/proton energy transferred to γ + jet. Measurements are compared to theory: P. Aurenche, M. Fontannaz, J.Ph. Guillet, Eur. Phys. J. C 44 (005) 395, Eur. Phys. J. C 77 (017) no.5, 34 contains HO corrections. Agrees well with data. S. P. Baranov, A. V. Lipatov and N. P. Zotov, Phys. Rev. D 81 (0) k t -factorisation based. Overestimates cross-section. 16 / 31

17 Studies of the diffractive photoproduction of isolated photons at HERA Reminder: z p fraction of Pomeron momenta transferred to γ + jet. x γ fraction of exchange boson momenta transferred to γ + jet. x p fraction of proton energy carried by Pomeron. Measurement: 456pb 1 of data form HERA-I and HERA-II, Q < 1GeV, 0. < y < 0.7 k T jets in lab. frame, cross-sections in bins of z p, x γ, x p. 17 / 31

18 Studies of the diffractive photoproduction of isolated photons at HERA Measurement: First measurement, precious information on diffraction. There is still something new to be found, e.g. z P > 0.9 is not expected and is not described by Rapgap3. MC. This is the case when Pomeron transfers almost all its energy to γ + jet. 18 / 31

H1@HERA reminder Second of two big experiments at HERA. 7.

19 reminder Second of two big experiments at HERA. 7.5GeV e ± collided with p (460/575/80/90GeV ) widest spectrum of physics. 0.5fb 1 of data, 500M events. O(300) members while running, 147 authors now. 19 / 31

20 H1 data preservation and recent results H1 data is stored in DESY and in RZG. H1 members in MPP: V. Chekalian, G. Grindhammer, C. Kiesling. Recent papers: V. Andreev et al. [H1 Collaboration], Determination of the strong coupling constant α s (m Z ) in next-to-next-to-leading order QCD using H1 jet cross section measurements, Eur. Phys. J. C 77 (017) no.11, 791 V. Andreev et al. [H1 Collaboration], Measurement of Jet Production Cross Sections in Deep-inelastic ep Scattering at HERA, Eur. Phys. J. C 77 (017) no.4, 15 V. Andreev et al. [H1 Collaboration], Measurement of D production in diffractive deep inelastic scattering at HERA, Eur. Phys. J. C 77 (017) no.5, / 31

21 Measurement of Jet Production Cross Sections in Deep-inelastic ep Scattering at HERA Reminder: e p Q (a) Measurement: e e q p Q (b) e e q q p Q (c) e e Neutral current DIS, 90pb 1 of data. 5.5 < Q < 80GeV and 0. < y < 0.6. k T jets in Breit frame are used. Cross-sections of inclusive jets, dijet and trijets simultaneously. As functions of jet p T (or combination of) in Q bins. q g p Q (d) e q g g 1 / 31

22 Measurement of Jet Production Cross Sections in Deep-inelastic ep Scattering at HERA Jets Inclusive jets H1 data MC (Djangoh) MC (Rapgap) Djangoh Rapgap Background Events Dijet sample H1 data MC (Djangoh) MC (Rapgap) Djangoh Rapgap Background Events Trijet sample H1 data MC (Djangoh) MC (Rapgap) Djangoh Rapgap Background jet P T [GeV] jet P T [GeV] jet P T [GeV] 3 Bin trijet Bin dijet Bin inclusive jet Trijet 1 H1 Completed jet program at H1. Inclusive jet Q Bin Bin inclusive jet Statistical correlations Dijet Bin dijet Bin trijet Correlation coefficient Measurement includes statistical correlations. Recent progress in theory adds to value: J. Currie, T. Gehrmann and J. Niehues, Phys. Rev. Lett. 117 (016) no.4, / 31

s s Determination of the strong coupling constant α s (m Z ) in next-to-next-to-leading order QCD using H1 jet cross section measurements R Z 0.0 0.15 0.

23 s s Determination of the strong coupling constant α s (m Z ) in next-to-next-to-leading order QCD using H1 jet cross section measurements R Z H1and NNLOJET World average [PDG16] H1 jets [NNLO] H1 jets [NNLO] (µ <m b ) JADE 3-jet rate [NNLO+NLLA+K] ALEPH y (Dissertori, et al.) [NNLO] 3 OPAL y 3 [NNLO] 3 GFitter EW fit [N LO] CMS inclusive jets 8TeV [NLO] µ R [GeV] First NNLO DIS fit. Multiple measurements, s = 300, 319, 5 < Q < 15000GeV, 0. < y < 0.7, Breit frame k T jets. Explicit α s running. Two approaches: Simultaneous fit of PDFs and α s to all DIS data using NNLO predictions. Use existing PDFs and NNLO predictions to fit α s. 3 / 31

24 Determination of the strong coupling constant α s (m Z ) in next-to-next-to-leading order QCD using H1 jet cross section measurements Both fits have χ /NDoF close to unity or less. Multiple scale choices were tested. α S fit (0) exp (6) had (3) PDF () PDFα (3) PDFset (7) scale. µ > 8 GeV as central, multiple other choices tested. NNPDF3.1 PDFs. Interplay between exp. and theory uncertainty. Scale uncertainty is dominant. PDF+α S fit (11) exp,np,pdf () mod () par (6) scale Q > GeV, H1 data only. PDFs are released as H1PDF017, consistency with NNPDF3.1 was checked. Scale uncertainty is dominant. 4 / 31

25 Measurement of D production in diffractive deep inelastic scattering at HERA Reminder: e( k) Q e(k ) ] [nb / GeV dσ/dq D* in diffractive DIS H1 Data NLO QCD, H1 006 Fit B dσ/dy [nb] D* in diffractive DIS H1 Data NLO QCD, H1 006 Fit B γ*(q) c... D* s x IP z IP c X(P X ) W data / NLO -4 1 data / NLO p( P) t Y(P Y ) Determined fraction of diffractive/inclusive D + production ratio. Compatibility with previous measurements and NLO predictions Q R D [%] [GeV ZEUS 003 ] Diffractive fraction D* production at HERA H1 017 H1 001 ZEUS 00 ZEUS < Q p t,d* < Q p t,d* 4 < Q p t,d* 1.5 < Q p t,d* Q p t,d* < 0 GeV, > 1.5 GeV, x IP < 0 GeV, > GeV, x IP < 400 GeV, > 1.5 GeV, x IP < 1 GeV, < 00 GeV, < > 1.5 GeV, x IP > 1.9 GeV, x IP < 0.03 < 0.04 < < y 5 / 31

26 Extra physics at HERA A. Gizhko et al., [and H1, ZEUS, PROSA] Running of the Charm-Quark Mass from HERA Deep-Inelastic Scattering Data, Phys. Lett. B 775 (017) 33. I. Abt et al., Investigation into the limits of perturbation theory at low Q using HERA deep inelastic scattering data, Phys. Rev. D 96 (017) no.1, More H1+ZEUS papers in preparation. 6 / 31

27 Running of the Charm-Quark Mass from HERA Deep-Inelastic Scattering Data χ m c (µ) [GeV] H1 and ZEUS preliminary m c (m ) scan for Q = GeV c m c (m ) [GeV] c H1 and ZEUS preliminary HERA!"#$!%$&'$()*+$,-%-$.%/01$&345 (prel.) PDG with evolved uncertainty µ [GeV] Multiple datasets, neutral current DIS,.5 < Q < 000GeV. NLO fits: xfitter/openqcdrad and FFNS n f = 3 ABM PDFs in multiple Q bins. First running of m c from HERA data. Q range m c (m c) m c (µ) ± ± ± 0.56 PDG: 1.8 ± 0.03 GeV 7 / 31

Investigation into the limits of perturbation theory at low Q using HERA deep inelastic scattering data Fits in 0.045 < Q < 30000GeV, 6 7 < x Bj < 0.65,.7 < W < 301.GeV with multiple datasets.

28 Investigation into the limits of perturbation theory at low Q using HERA deep inelastic scattering data Fits in < Q < 30000GeV, 6 7 < x Bj < 0.65,.7 < W < 301.GeV with multiple datasets. Extraction of σ γp and comparison to different models/parametrisation that are valid in Regge or pqcd regions in overlap region. Data suggests smooth transition between Regge and pqcd regions, confirms A. Caldwell, The evolution of σ γp with coherence length, New J. Phys. 18 (016) no.7, No changes in behaviour between regions nature does not know about ppereturbation theory. 8 / 31

ZEUS: in progress Dominant uncertainty on α s in jet analysis is scale variation. Can be reduced with resummation for some HFS observables, e.g. for event shapes. D. Kang, C. Lee and I. W.

29 ZEUS: in progress Dominant uncertainty on α s in jet analysis is scale variation. Can be reduced with resummation for some HFS observables, e.g. for event shapes. D. Kang, C. Lee and I. W. Stewart, DIS Event Shape at N3LL, PoS DIS 015 (015) 14 Example of event shape: thrust, calculated in current hemisphere of Breit frame. T = i pi n i pi, where n is the virtual-photon direction (T γ ) or the axis that minimises the thrust (T h ). Very similar to e + e event shapes. 9 / 31

30 ZEUS: in progress No event shape measurement exists with HERA-II data. Will be a valuable input for comparison to NNLO and/or N 3 LL calculations. ZEUS(prel.) ) T 1/N dn/d(1-t <Q <30Gev, 0.01 <x<0.05, 160<Q <30Gev, 0.004<x<0.01, 80 <Q <160Gev, 0.01<x<0.050, T T 3 1 HERA-II neutral current. Simultaneous measurement in 16 x Q bins: < Q < 0480GeV, < x < 0.6. Six event shapes: T γ, T h, B γ, B h, C and M. 30 / 31

31 Conclusions Extremely interesting and valuable results obtained by the collaborations. Manpower problem is visible, but more interesting and novel analysis are in development. The preserved data in DESY and MPP makes it available and attracts physicists outside of experiments H1 and ZEUS have successful examples of collaboration with external theoretical and experimental groups. Sometimes good ideas/predictions are coming late. Cheaper and faster to preserve than rebuild and re-run. New ideas in physics and analyses are welcome. 31 / 31

QCD Results from HERA

QCD Results from HERA Daniel Britzger for the H1 and ZEUS Collaborations La Thuile, Italy 30.03.2017 1 Deep-inelastic ep scattering Neutral current scattering (NC) ep e'x Covered topics in this talk e'(k')