“School of Particles And Accelerator”

Back to Papers Home
Back to Papers of School of Particles And Accelerator

Paper   IPM / Particles And Accelerator / 11893
School of Particles and Accelerator
  Title:   Suppression of Upsilon excited states in PbPb collisions at a nucleon-nucleon centre-of-mass energy of 2.76 TeV
1.  Hessamadin Arfaei
2.  Hamed Bakhshiansohi
3.  Seyed Mohsen Etesami
4.  Ali Fahim
5.  Majid Hashemi
6.  Abideh Jafari
7.  Mohsen Khakzad
8.  A Mohammadi
9.  Mojtaba Mohammadi Najafabadi
10.  Saeid Paktinat Mehdiabadi
11.  Batool Safarzadeh
12.  Maryam Zeinali
  Status:   Published
  Journal: Phys. Rev. Lett.
  No.:  052302
  Vol.:  107
  Year:  2011
  Supported by:  IPM
A comparison of the relative yields of U resonances in the m + m- decay channel in PbPb and pp collisions at a centre-of-mass energy per nucleon pair of 2.76 TeV, is performed with data collected with the CMS detector at the LHC. Using muons of transverse momentum above 4 GeV/c and pseudorapidity below 2.4, the double ratio of the U(2S) and U(3S) excited states to the U(1S) ground state in PbPb and pp collisions, [U(2S + 3S)/U(1S)]PbPb/[U(2S + 3S)/U(1S)]pp, is found to be 0.31 +0.19 -0.15 (stat.) +-0.03 (syst.). The probability to obtain the measured value, or lower, if the true double ratio is unity, is calculated to be less than 1

Download TeX format
back to top
scroll left or right