Particle Physics: O(1 TeV) and O(1 pb^-1)

[etayf]

I saw a sign in particle physics ;O(1 TeV) and O(1 pb^-1). TeV is unit of energy and pb^-1 is unit of cross scetin I wonder why these signs are putting into parahenthesis

 

[ChrisVer]

This notation means of order of... ...
So O(1TeV) means of order of 1 TeV..

another thing is in Landau symbols:
http://mathworld.wolfram.com/LandauSymbols.html
But I think your question refers to the 1st line I posted...

 

[jtbell]

This notation means of order of... ...
So O(1TeV) means of order of 1 TeV..

More explicitly, "order of magnitude" (power of ten), i.e. "probably greater than 0.1 TeV and less than 10 TeV"

 

[etayf]

thanks for answers