ALICE Policy for official figures

ALICE official figures

This section presents the definition, usage, and approval mechanisms of the various types of official ALICE figures:

All figures related to detector performance or physics results must be approved as official ALICE figures, following the procedures specified in this section, before they can be shown outside the Collaboration.

Each candidate for an official figure must be approved by the relevant PWG or Project Group. If identification of the relevant group is not clear, the Physics Coordination chooses the PWG that is best suited for discussing the figure.

Bookkeeping of Figures

  • Each PWG and Project, in consultation with the EB, maintains an ALICE Repository of Figures accessible via a web interface.
  • The Repository  contains Simulation, Performance,  Preliminary, and Published figures. 
  • Each figure entry in the Repository of Figures will specify a Contact Person and  will be accompanied by a complete caption.
  • Each figure will include the following:
    • Clearly labeled variables and units of measure.
    • A legend specifying the colliding systems and energy and the nature of the  uncertainties (statistical and systematic).
    • Published figures must explicitly include the label "ALICE".
    • Each unpublished figure will specify its category (Simulation, Performance, Work in Progress, Preliminary).
    • Only the most recent version of each Performance plot should be available in the Repository.

The following paragraphs define the various types of official figure, their usage and their bookkeeping.

ALICE Simulation figures

ALICE Simulation figures contain results of simulations of physics events and/or detector response, for example to illustrate expected performance of the detector, the size of corrections for detector effects, or reference distributions from event generators. Simulation figures must be accompanied by all relevant information to reproduce the figure, including version numbers of software used, generator settings and a precise description of how the quantities in the figure were calculated from the simulation. This information is stored together with the figure in the Repository of figures. Each ALICE Simulation figure has a unique identification number and must be labeled 'ALICE Simulation'. ALICE Simulation figures are discussed in the relevant PAG or PWG approved by the PWG conveners or Project Leaders in consultation with the PAG coordinators.

ALICE Performance figures

ALICE Performance figures are used to illustrate aspects of detectors performance, in a general context, independent of a specific analysis. Any figure that illustrate intermediate steps in an analysis are ALICE Preliminary figures.

ALICE Performance figures are intended to illustrate the quality of the calibration, the behavior of one or several ALICE (sub-) detectors, the resolution for tracking or particle identification techniques, etc. Performance figures can be shown outside the collaboration after approval by the PWG conveners or Project Leaders of relevant PWG/detector system. Performance figures evolve with time, for instance with a new version resulting from a new data set. Any change of the figure requires explicit re-approval by the PWG conveners or project leaders.

Each ALICE Performance figure has a unique identification number and must be labeled 'ALICE Performance' and stored in the Repository of figures.

ALICE Work in Progress figures

ALICE Work in Progress figures are transient, intended only for progress reports to funding agencies, review committees, reports of students within ALICE institutes, and national physics society meetings. They should not be used for general presentations such as conference talks and seminars, other than these exceptional cases.

ALICE Work in Progress figures illustrate the status of an analysis, in which some corrections may not yet have been applied and from which quantitative physics conclusions cannot be drawn. The dataset and methods used to generate the figure must be clear and available to the ALICE Collaboration.

Each usage of a Work in Progress figure must be explicitly approved by the relevant PWG Conveners or Project Leaders, Physics Coordination and Conference Committee.

Work in Progress figures are not entered into the Repository of Figures and will not receive a figure identification number from the EB.

ALICE Work in Progress figures should not be made publicly accessible, e.g., the slides cannot be made accessible on a web page or in a meeting program.

ALICE Preliminary figures

ALICE Preliminary figures are intended for presentation at international conferences and workshops.

There are three subcategories of ALICE Preliminary figures:

  1. Physics Preliminary figures show the results of analysis and must include estimates of all statistical and systematic uncertainties in the underlying analysis that are relevant for the interpretation of the measurement and the understanding of the underlying physics. There will be only one version of each preliminary result. Numerical values of preliminary results may be given to persons who are not member of the ALICE collaboration on request. Such requests are handled by Physics Coordination. Preliminary results are superseded by the published version of the results.
  2. Technical Preliminary figures provide supporting information about the analysis. Technical Preliminary figures are for example used to illustrate intermediate steps in the analysis or to compare different analysis methods for the same physical quantity. Technical Preliminary figures may show results that are not corrected for detector effects or results without systematic uncertainties. For Technical Preliminary figures, numerical values are not available to people outside the Collaboration.
  3. Derived Preliminary figures contain reported results from a Physics (or Technical) Preliminary figure, for example to compare a (new) model prediction, with an existing result of a different ALICE measurement, or with results of other experiments.

Each ALICE Technical or Physics Preliminary figure must be presented at the Physics Forum and be approved by the PWG conveners and Physics Board before it can be shown outside the Collaboration. Technical Preliminary figures may subsequently be updated (for example with a larger data sample) after approval by the PWG conveners and Physics Board. It can not be changed and modification can only be done at the publication level. ALICE Technical or Physics Preliminary figures must be accompanied by an Analysis Note, which contains all relevant information about how the figures were obtained, including software version(s), the data set(s), selections that were used, analysis algorithms and a description of the calculation of all uncertainties. The Analysis Note is made available to the collaboration before the results are presented at the Physics Forum.

Derived Preliminary figures are presented at a Physics Forum and can only be shown outside the collaboration after approval by the PWG conveners and the Physics Board.

Each ALICE Preliminary figure has a unique identification number, must be labeled "ALICE Preliminary" and is stored in the Repository of figures.

An ALICE Preliminary Figure may be withdrawn only in the case that an error is found in the analysis that invalidates the physics message of the figure. Such cases have to be brought to the attention of the Physics Board by the PWG conveners after which the figure will be withdrawn from the Repository of figures. An Analysis Note must be prepared to document the error and the withdrawal of the figure. In this case the PB decides if the withdrawn Preliminary figure can be replaced by a corrected version or only by publishing the result. If an ALICE Public Note is published, a new corrected version containing the correct figure must be submitted for the approval of the EB.

If some of the preliminary figures updated by final analysis do not appear in the publication, for example because of a restriction on the article length, the corresponding updated figure should be made publicly available through a procedure that will be specified by the EB and PB.

ALICE Published figures

ALICE Published figures are all figures containing final results that appear in a publication or Public Note. Each ALICE Published figure has a unique number and is stored in the repository of figures, with reference to the corresponding publication or Public Note. When a figure is published, the corresponding Preliminary figure(s) are removed from the repository (or marked obsolete).

Conflicts and exemptions

Conflicts regarding content and presentation of figures will be resolved by the Spokesperson, in consultation with PB and EB chairs, PWG convener(s) and Project leader(s). Exemptions from the above general rules may only be granted by the Spokesperson, and only in exceptional circumstances.