Photon Structure
This page contains the collection of results on the structure of the photon which have been presented in Phys Rep 332(2000) 165-317. The full paper is available as PDF or PostScript file. A preprint version of this work is available as hep-ex/9912049.This page provides access to the Encapsulated PostScript files of all Figures. In addition listed are the numerical results presented in the Tables of the appendices C and D. Since the tables are not completely standardised it is advisable to always consult the manuscript before using the numerical results! For convenience, the gzip'ed tar files which always contain the complete most up-to-date Set of Figures and Set of Tables are also available. The results have been collected with great care, however mistakes are not exluded. Please feel free to contact Richard Nisius should you have any comment or question.
Whenever new data on photon structure functions are available or preliminary results are finalised, I intend to update the summary figures. In this case the figure is marked as (updated) and you are directed to a new page giving the record of the changes made. Tables will only be updated should there be an error discovered and corrected.
List of known misprints and acknowledgements
Unfortunately, there are still some misprints in the document.
- Page 182, Equation 27: In the formula for P2max it should read theta2primesquared instead of theta2prime.
- Page 207, item 7 GRsc: The sentence, `The contribution of charm quarks was changed from 1.5 to 1.4 GeV.`, has been truncated and should be replaced by: `The contribution of charm quarks is taken from the leading order Bethe-Heitler formula, both for the leading order and the higher order parametrisations, and the mass of the charm quarks was changed from 1.5 to 1.4 GeV.`
- Page 287, Equation A.16: The Equation should be broken into four lines, i.e. the second line should be split into two before the second occurrence of alpha/2pi.
- Page 303, Table 26: For Q^{2}=59.0 GeV^{2} the bin boundaries in x should read 0.050 - 0.100 - 0.350 - 0.600 - 0.800. I like to thank Martin Erdmann for spotting this typo.
- Page 310, Ref [49]: The reference shoud read Nucl Phys B199 instead of PhysLett B199. I like to thank Johannes Hess for spotting this typo.
If you spot something else that is wrong, please let me know.
List of Figures
Figure | Description |
Fig01 | Probing the structure of quasi-real photons, g, by highly virtual photons, g^{*}. |
Fig02 | The different appearances of the photon. |
Fig03 | A diagram of the reaction ee –> ee ff, proceeding via the exchange of two photons. |
Fig04 | The different contributions to the reaction ee –> ee g^{(*)}g^{(*)} –> ee ff. |
Fig05 | Illustrations of the scattering angles barphi, theta^{*} and chi in the photon-photon centre-of-mass system. |
Fig06 | A schematic view of the OPAL detector. |
Fig07 | The kinematical coverage of the OPAL detector. |
Fig08 | The predicted differential cross-section dsigma/dx for the reaction ee –> ee µ^{+}µ^{-} for the acceptance of the PLUTO experiment, and for two different lower limits on W. |
Fig09 | The predicted differential cross-section dsigma/dx for the reaction ee –> eeµ^{+}µ^{-} for some typical acceptances of a LEP experiment. |
Fig10 | Comparison of the equivalent photon and the Weizsäcker-Williams approximations. |
Fig11 | A diagram of the reaction eg –> eg^{*}g –> e ff . |
Fig12 | The structure functions F_{2,QED}, F_{A,QED} and F_{B,QED} for µµ final states at Q^{2}=1 GeV^{2}. |
Fig13 | The structure functions F_{2,QED}, F_{A,QED} and F_{B,QED} for µµ final states at Q^{2}=100 GeV^{2}. |
Fig14 | The P^{2} dependence of the structure function F_{2,QED}. |
Fig15 | The QPM prediction for the structure function F_{2} for light quarks. |
Fig16 | Comparison of the parametrisations of the x dependence of the leading order asymptotic solution of F_{2}. |
Fig17 | Comparison of the asymptotic solution and the leading order GRV parametrisation of F_{2}. |
Fig18 | The structure function F_{2} in the limit Q^{2} >> P^{2} >> Lambda^{2}. |
Fig19 | The leading order contributions to F_{2,h}. |
Fig20 | The point-like heavy quark contribution to F_{2} for various values of Q^{2}. |
Fig21 | Comparison of parametrisations of the hadron-like contribution to the photon structure function F_{2}. |
Fig22 | The Q^{2} dependence of the photon structure function F_{2} in comparison to the hadron-like contribution. |
Fig23 | The structure function F_{2} from the LAC parton distribution functions. |
Fig24 | The structure function F_{2} from the WHIT parton distribution functions. |
Fig25 | Comparison of the GRV leading order and next-to-leading order parametrisations of the photon structure function F_{2}. |
Fig26 | Comparison of the higher order structure function F_{2} from AFG and GRV. |
Fig27 | Comparison of the leading order GRV and GRSc parametrisations of F_{2}. |
Fig28 | The structure function F_{2} from the SaS parton distribution functions for several values of Q^{2}. |
Fig29 | Predictions for the Q^{2} evolution of the photon structure function F_{2} for various x ranges. |
Fig30 | Comparison of leading order parametrisations of the photon structure function F_{2} for virtual photons. |
Fig31 | The variation of the P^{2} suppression of F_{2} in the SaS1D parametrisations. |
Fig32 | The predicted P^{2} suppression of the photon structure function F_{2}(uds). |
Fig33 | Comparison of the photon structure function F_{2} for virtual photons with the purely perturbative point-like part. |
Fig34 | The point-like and hadron-like contributions to F_{2,c} (updated). |
Fig35 | The measured average structure function <F_{2,QED}> from the CELLO, DELPHI, L3 and the TPC/2g experiments, compared to QED predictions. |
Fig36 | The world summary of F_{2,QED} measurements (updated). |
Fig37 | The measured Q^{2} evolution of F_{2,QED} (updated). |
Fig38 | The dependence of F_{2,QED} on P^{2} and on the mass of the muon. |
Fig39 | The measurements of F_{A,QED} / F_{2,QED} and ½ F_{B,QED} / F_{2,QED} (updated). |
Fig40 | The measurements of F_{A,QED} and F_{B,QED}. |
Fig41 | The measurement of the differential QED cross section dsigma/dx for highly virtual photons. |
Fig42 | The general behaviour of the hadronic energy flow. |
Fig43 | The correlation between the measured and generated hadronic invariant mass. |
Fig44 | The measured E_{t,out} distribution for <Q^{2}> = 13 GeV^{2} in bins of x. |
Fig45 | The corrected hadronic energy flow for <Q^{2}> = 13 GeV^{2}. |
Fig46 | The corrected hadronic energy flow for <Q^{2}> = 135 GeV^{2}. |
Fig47 | Comparison of different methods for the reconstruction of the invariant mass of the hadronic final state. |
Fig48 | The measured hadronic energy flow from L3. |
Fig49 | Measurements of the hadronic structure function F_{2} except from LEP. |
Fig50 | Comparison of measurements of F_{2} at low values of Q^{2}. |
Fig51 | Preliminary update of F_{2} at low values of Q^{2} from OPAL. |
Fig52 | The measurements of F_{2} at low values of Q^{2} from L3. |
Fig53 | The first measurement of F_{2} for sqrt(s_{ee}) > m_{Z} . |
Fig54 | Measurements of the hadronic structure function F_{2} from LEP (updated). |
Fig55 | Summary of measurement of the hadronic structure function F_{2} (updated). |
Fig56 | The measured Q^{2} evolution of F_{2} for three active flavours. |
Fig57 | The measured Q^{2} evolution of F_{2} from OPAL (updated). |
Fig58 | The measured Q^{2} evolution of F_{2} from L3. |
Fig59 | The measured Q^{2} evolution of F_{2} at medium x (updated). |
Fig60 | Summary of the measurements of the Q^{2} evolution of F_{2} (updated). |
Fig61 | Measurements of the Q^{2} evolution of F_{2} compared to a linear fit (updated). |
Fig62 | The Q^{2} evolution of F_{2} for three active flavours compared to the asymptotic solution and the QPM prediction (updated). |
Fig63 | The effective photon structure function F_{2,eff} from PLUTO. |
Fig64 | The effective photon structure function F_{2,eff} from L3. |
Fig65a , Fig65b | The virtuality dependence of F_{2,eff}. |
Fig66 | The hadronic cross-section for the exchange of two virtual photons from L3. |
Fig67 | The hadronic cross-section for the exchange of two virtual photons from OPAL. |
Fig68 | The forward region of a future linear collider detector. |
Fig69 | The production mechanism for high energetic photons. |
Fig70 | Prospects for structure function measurements at a future linear collider. |
Fig71 | Prospects for the measurement of the Q^{2} evolution of F_{2} at a future linear collider (updated). |
Fig72 | Published results on sigma_{gg} as a function of W. |
Fig73 | Preliminary results on sigma_{gg} as a function of W . |
Fig74 | Fits to sigma_{gg} using various data and fit assumptions. |
Fig75 | Transverse momentum distribution dsigma / dp_{T} for hadron production in photon-photon scattering compared to other experiments. |
Fig76 | Transverse momentum distribution dsigma / dp_{T} for hadron production in photon-photon scattering compared to next-to-leading order calculations. |
Fig77a , Fig77b | Angular dependence of di-jet production in photon-photon scattering. |
Fig78 | Transverse energy distribution dsigma / dE_{jet,T} for jet production in photon-photon scattering compared to next-to-leading order calculations. |
Fig79 | Transverse energy distribution dsigma / dE_{jet,T} for jet production in photon-photon scattering compared to predictions for different parton distribution functions. |
Fig80 | Differential cross-sections for charm quark production with semileptonic decays into electrons. |
Fig81 | Differential cross-sections for charm quark production with tagged D^{*} mesons. |
Fig82 | The separation of the D^{*} production into direct and single-resolved contributions. |
Fig83 | Total cross-section for charm quark production. |
Fig84 | Di-jet cross-section in photon-proton scattering compared to next-to-leading order QCD predictions. |
Fig85 | Inclusive di-jet cross-section for photon-proton scattering from H1. |
Fig86a , Fig86b | Leading order effective parton distribution function of the photon from H1. |
Fig87a , Fig87b | Measurements of the gluon distribution function of the photon from H1. |
Fig88 | Triple differential jet cross-section dsigma/dP^{2}dE_{T}^{2}dx_{g} for virtual photons from H1. |
Fig89 | Leading order effective parton distribution function of virtual photons from H1. |
Fig90 | The P^{2} suppression of the leading order effective parton distribution function of virtual photon from H1. |
List of Tables
Table | Description |
TabC01 | Results on the average photon structure function <F_{2,QED}> from the CELLO experiment. |
TabC02 | Results on the average photon structure function <F_{2,QED}> from the DELPHI experiment. |
TabC03 | Results on the average photon structure function <F_{2,QED}> from the L3 experiment. |
TabC04 | Results on the photon structure function F_{2,QED} from the OPAL experiment. |
TabC05 | Results on the photon structure function F_{2,QED} from the OPAL experiment, continued. |
TabC06 | Results on the photon structure function F_{2,QED} from the PLUTO experiment. |
TabC07 | Results on the average photon structure function <F_{2,QED}> from the TPC/2g experiment. |
TabC08 | Preliminary results on the photon structure function F_{2,QED} from the DELPHI experiment. |
TabC09 | Results on the photon structure functions F_{A,QED} and F_{B,QED} from the L3 experiment. |
TabC10 | Results on the photon structure functions F_{A,QED} and F_{B,QED} from the OPAL experiment. |
TabC11 | Preliminary results on the photon structure function ratios F_{A,QED} / F_{2,QED} and ½ F_{B,QED} / F_{2,QED} from the DELPHI experiment. |
TabC12 | Differential cross-section dsigma/dx for two exchanged virtual photons. |
TabD01 | Results on the photon structure function F_{2} from the ALEPH experiment. |
TabD02 | Results on the photon structure function F_{2} from the AMY experiment. |
TabD03 | Results on the photon structure function F_{2} from the DELPHI experiment. |
TabD04 | Results on the photon structure function F_{2} from the JADE experiment. |
TabD05 | Rsults on the photon structure function F_{2} from the L3 experiment. |
TabD06 | Results on the photon structure function F_{2} from the OPAL experiment (updated). |
TabD07 | Results on the photon structure function F_{2} from the PLUTO experiment. |
TabD08 | Results on the photon structure function F_{2} from the TASSO experiment. |
TabD09 | Results on the photon structure function F_{2} from the TPC/2g experiment. |
TabD10 | Results on the photon structure function F_{2} from the TOPAZ experiment. |
TabD11 | Additional preliminary results on the photon structure function F_{2} from the ALEPH experiment. |
TabD12 | Additional preliminary results on the photon structure function F_{2} from the DELPHI experiment. |
TabD13 | Additional preliminary results on the photon structure function F_{2} from the L3 experiment. |
TabD14 | Results on the Q^{2} evolution of F_{2} for three active flavours. |
TabD15 | Results on the Q^{2} evolution of F_{2} for four active flavours. |
TabD16 | Preliminary results on the Q^{2} evolution of F_{2}. |
Last Change: 16-Jul-2009 by Richard Nisius.