Description of the display items

This section deals with all the entities that can be displayed by A3D.

Hits

Hits are displayed as cubes. The color of a hit is related to its time and the size to the amplitude of the hit. Hit-size is computed by the following formula size = hit_size * npe^hit_size_power , where hit_size and hit_size_power can be set in the preferences-file.

relevant parameters in the .ini file

• use_hue_for_time: If true so-called hue is used for determining the colors of the hits as function of their time. If false hit colors are interpolated between first_hit_color and last_hit_color.

• auto_minmax_time: To determine the hit-colors the program must know what the minimum and maximum hit times are. Setting this option to true, will cause A3D to scan the hits for the max. and min times. Otherwise min_hit_time and max_hit_time can be used to manually set these values.
• hit_size and hit_size_power: see above.

Tracks

There are different types of tracks (such as neutrino, track_in, fit, prefit). Each type of track is displayed as a line with a separate color.

relevant parameters in the .ini file

• mc_track_color, neutrino_track_color, fit_track_color and prefit_track_color: color of these tracks.
• non_muons_track_length: Monte Carlo tracks that are not muons will be drawn with this length.

Spheres

Antares' reconstruction software can fit an expanding sphere through the hits. The idea being that this topology corresponds with a flash of light or with a shower. These spheres can also be drawn by A3D.

relevant parameters in the .ini file

• sphere_detaillevel: Spheres are approximated by polygons for drawing them. This sets how fine the mesh should be.
• sphere_style:0=solid, 1=lines and 2=points.
• sphere_size: the radius of the sphere.

Photons

Hits that are caused by a track have a line drawn pointing to that track... these lines are called 'photons'. They have the same color as the hit and the angle between the track and the photon is 41 degrees (the Cerenkov angle). This feature should be regarded as a convenient way to display the hit-track relationship rather than anything physical... in reality photons may be emitted under different angles, scattered or be produced by secondary particles (in some events photons seem to be originating at points were the track has not even started).

Strings

Strings are simply displayed as a line. The string number can be plotted at the top. From version v1r3 on, strings are drawn as a curved line going through the om-cluster locations.

relevant parameters in the .ini file

• line_color: color of the line.
• draw_string_number: when true, the string number is shown at the top of each string.

Optical Modules

Optical modules are plotted as a line originating on the string, pointing in the 'direction of the om' and ending up in the position of the om. If you want, OM's can be displayed further from the sting than they actually are to increase their visibility (this also affects the position of the hits).

relevant parameters in the .ini file

• om_color: The color of the optical module.
• om_detaillevel: If this is 1, oms are drawn as spheres with a size which is set by om_sphere_size and a detail-level given by om_sphere_detail.
• om_position_exageration_factor: Determines the factor with which the distance to the line is increased when the OM is drawn.

Slow control hardware

Transponders, hydrophones and tiltmeters are displayed as pyramids, spheres and tetrahedrons respectively.

relevant parameters in the .ini file

• transponder_size, tiltmeter_size and hydrophone_size : size with which these object are drawn.
• transponder_color, tiltmeter_color and hydrophone_color : color with which these object are drawn.

Ground

The Seabed can be displayed as a grid of lines (with optionally some fancy colors). In addition the letters N,E,S,W are strategically placed in the north, east, south and west.

relevant parameters in the .ini file

• draw_nesw: turns the north, east, south, west letters on/off.
• draw_ground: turns the ground drawing on/off.