Linear Collider Detector Data Description

This is a description of the data on the Linear Collider Detector (LCD) Snowmass CD. You can browse the data here.

The directories contain generator level particle files with filetype .stdhep, and detector simulation level files with filetype .sio. These two filetypes are understood by the JAS analysis package.

Two LCD detector designs are simulated, the so called "Large" and "Silicon" detectors. The detectors are described in detail in the "Orange Book". The Large detector contains a large (~2 meter radius) TPC for tracking and a 3 Tesla field with the coil outside both the EM and Had Calorimeters which are both made of lead/scintillator. The Silicon detector contains a five layer silicon strip tracker with a 5 Tesla field coil outside both EM and Had calorimeters. The EM Cal is silicon/tungsten and the Had Cal is stainless_steel/scintillator.

Directory names that end with "L" or "LD" contain simulations of the Large detector, Directory names that end with "S" or "SD" contain simulations of the Silicon detector. The remaining directories contain generator level files.

The directory names that begin with "partRes" contain single particle events. The remaining directories contain signal process physics events designated as follows:

• paqq – Pandora/Pythia based light quark (udscb) events.
• patt – Pandora/Pythia based ttbar events.
• paZZ – Pandora/Pythia based ZZ events.
• paZH – Pandora/Pythia based ZH events with Higgs mass = 114GeV.
• pyWW – Pythia based WW events.

In the filename of all the files there is a date of the form DDMMYY which is a release date. The single particle data files contain either electrons or pi-. There are 5000 single particle events at each of 2,3,4,5,10,20 and 50 GeV. The filename contains a number indicating the energy of the particles in that file. The particles are emitted from the IP at right angles to the beam line. The phi direction is randomly selected. (Note: due to time limitations of batch queues some of the 50GeV single particle file detector simulations do not contain the full 5000 events.)

The signal process events for the Large and the Silicon detectors are based on interaction of 250GeV e+ and e- beams and contain ISR, FSR and beamsstrahlung effects. Each file contains 100 events. The filenames contain a sequence number for the file. The detector simulations were made with the generator level data and the sequence numbers match the generator level with the simulation level data. (Note: all significant generator level information is included in the simulation level files.)

This table describes the relative cross-sections for the five signal processes at 500GeV CM energy with electron beam polarization as indicated.

The qqbar events can radiate down to the Z pole and the WW and ZZ events tend to be forward, therefore a lab frame cos theta cut of 0.9 has be used and is accounted for in the relative cross-sections.