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High Energy Physics

High energy physics (or particle physics) datasets are used for the researches on the particles, basic building blocks of universe and the ways they interact with each other. The datasets are also used on the studying the origin and evolution of the universe.

DYB

The data comes from Daya-Bay (DYB) reactor neutrino experiment, which is mainly used to study neutrino oscillation and other frontier topics of high energy physics. By analyzing the data, the values of theta13 and other key properties of neutrino can be accurately measured. Neutrino physics is of great significance to understand the origin of the universe and the grand unified theory of particle physics.

Data Description
The data of Daya-Bay neutrino experiment include: raw data, reconstruction data and simulation data. The raw data consist of physics data and calibration data. Physics data are the electrical signals collected from detectors. About 300 files are collected per day with the file size of 1GB.

Reconstruction refers to the process of calculating and restoring the information of physics events (such as energy, direction, position, etc.) from the raw or simulation data, and the generated reconstruction data are used for subsequent physical analysis.

Calibration data are the calibration of by detector performance. The calibration data are used to calculate the absolute scales of physics parameters of events during the process of reconstruction.  

Simulation data are generated by Monte Carlo simulation to mimic the physics process when neutrino traverses the experiment apparatus (the detector). The data format is similar to the real raw data. The Monte Carlo simulation is used to help physicist to understand the detector performance or look for unexpected physics processes.

Data access policy
Only the Daya-Bay collaborators can access the data. More details can be found at http://dayabay.ihep.ac.cn/DocDB/0102/010251/003/DayaBay_bylaws20.pdf

Data analysis software
LAF (Lightweight Analysis Framework), a lightweight physical analysis framework software, is used in the physical analysis of Daya-Bay Neutrino experiment. More details can refer to: http://dayabay.ihep.ac.cn/tracs/dybsvn/browser/dybgaudi/trunk/NtupleAna/Examples/IBDSelectAlg
 

BESIII

The BESIII data are collected from the BESIII experiment at the BEPCII electron-positron collider for the studies of hadron physics and τ-charm physics with the highest accuracy achieved in the world. The physics topics related to BESIII data analyses include the light hadron physics, charmonium physics, tau and QCD-related research, and charm physics and new physics.

Data Description
The data products of BESIII consist of three subsets, they are raw data taken from BESIII detector, simulation data generated by Monte Carlo simulation and reconstructed data produced from raw data. Reconstructed data are divided into different physics channels and details can be checked in the second half of this page.

Data Access Policy
To access the BESIII data, any organization or person should request the membership of BESIII Collaboration. The membership is managed by the Institution Board of the Collaboration. The completed policy is described at http://english.ihep.cas.cn/bes/doc/2823.html.
 

CMS

CMS (Compact Muon Solenoid) experiment data are collected by a general-purpose detector called “Compact Muon Solenoid” at the LHC (Large Hadron Collider). CMS experiment data are used to study the Standard Model (including the Higgs boson) and to search for extra dimensions and particles that could make up dark matter.

Data Description
According to the different research purposes, CMS experiment data consist of new Physics data, Higgs Physics data, Top Physics data, Standard Model Physics data, Soft QCD Physics data, Dark Matter Physics data, B Physics data, Detector Study data. These data are based on CMS detector collection or simulation production. Since 2010, the data have been acquired on energy of 7Tev, 8Tev and 13Tev and integral brightness of 6.1/fb, 23.3/fb and 163/fb.
New Physics data are used to study the new physics beyond Standard Model.Higgs Physics data are used to study Higgs boson, including accurately test the characteristics of Higgs boson.Top Physics data are used to study the property of “top quark”, which is the heaviest particle.Standard Model data are used for the research of the physics process of Standard Model.Soft QCD data consist of multi-parton scattering, fragmentation, underlying event, etc.Dark Matter data are used to find the evidence of dark matter existence.B physics data are used for the research of heavy flavor quark, b quark and c quark.Detector Study data are used to check detector parameters and the correction of data produced from detector.

Data Access Policy
CMS experiment data are owned by CMS Collaboration. To access the data, any organization or person should request to be the member of CMS Collaboration. An organization or institution that make contributions to CMS experiment can apply to be a member of CMS Collaboration. An individual should join an organization or institution which has been the member of CMS Collaboration, and then he/she can be the member of CMS Collaboration. The Institution Board of CMS experiment has the right to approve a member request.

Data Analysis Software
CMSSW is the CMS data analysis software. With CMSSW, users can anarealyze the data listed below. CMSSW can be found at: https://github.com/cms-sw/cmssw, the tutorials can be found at: http://cms-sw.github.io/.
 

ATLAS

ATLAS (A Toroidal LHC ApparatuS ) experiment data are collected by the detector ATLAS at the LHC (Large Hadron Collider). ATLAS experiment data are used to investigates a wide range of physics, from the search for the Higgs boson to extra dimensions and particles that could make up dark matter.

Data Description
ATLAS experiment data consist of raw data, simulation data and reconstruction data. 

The ATLAS detector generates 1-2 GB of raw data per second. The simulation data are generated by the Monte Carlo method according to the physical model, which is widely used in detector design and physical analysis. Reconstruction data are the data of restoring the physical information (such as energy, position, etc.) based on the electronic signals. Reconstruction data will be used for subsequent physical analysis.

Data Access Policy
ATLAS data access policy has different access levels. The details can be found at: https://cds.cern.ch/record/2002139?ln=en

Data Analysis Software
Athena is the ATLAS data analysis software. Athena follows the Apache 2.0 license. It can be found at: https://atlassoftwaredocs.web.cern.ch/athena/.
 

LHCb

LHCb (Large Hadron Collider beauty) experiment data are collected by the LHCb at the Large Hadron Collider. LHCb experiment data are used to study the particle called the “beauty quark”, or “b quark”, and further to investigate the slight difference between matter and antimatter. “b quark” is hidden in the massive amount of experiment data. Physicists can dig out the “b quark” from the experiment data with the proper algorithms. Besides, LHCb data include part of simulation data used as the basics of subsequent analysis.

Data Description
LHCb data have three subsets, they are proton-proton collision data, heavy ion and fixed-target data and Monte Carlo simulation data. The proton-proton collision data are used to study the rare decay and CP violation processes in heavy flavor hadron decay, so as to accurately test the standard model and indirectly find new physical processes. It can also be used to research the basic properties of strong interaction and search for new resonance states. The heavy ion collision data are unique for LHCb experiment which can be used to study cold nuclear matter and quark gluon plasma in high-energy nuclear physics. The Monte Carlo simulation data generated by computer represent the physical process of the target and the role of the detector, which are used to make comparison with the experimental data.

Data Access Policy
LHCb experiment data are owned by LHCb Collaboration. To access the data, any organization or person should request to be the member of LHCb Collaboration. An organization or institution that make contributions to LHCb experiment can apply to be a member of LHCb Collaboration. An individual should join an organization or institution which has been the member of LHCb Collaboration, and then he/she can be the member of LHCb Collaboration. The Institution Board of LHCb experiment has the right to approve a member request, the details how to request to be a LHCb member can be found: https://twiki.cern.ch/twiki/pub/LHCb/LHCbDataPreservation/130321-LHCbDataAccessPolicy.pdf      

Data Analysis Software
LHCb data analysis software is used to analyze the LHCb data. DaVinci is the main data analysis software of LHCb. It’s developed based on Gaudi framework and provided as a group of components. To use DaVinci software, please refer to http://lhcbdoc.web.cern.ch/lhcbdoc/analysis/  
 

L3C

The L3 Cosmic, or L3C, was the experiment carried out the research on an important subject concerning the frontier of non-accelerator based particle physics using L3 detector at LEP. The data collected from L3C experiment provides a unique tool to study cosmic ray and particle astrophysics.