press release #33
First scientific publication from LHC 7 TeV run appears in Phys. Rev. Letters!
Since 1995 group from Yerevan Physics Institute headed by Albert Sirunyan participates in the preparation of the Compact Muon Solenoid (CMS ) experiment.
YerPhI group was involved in the detectors design and construction, data analysis software development as well as in test beam data taking & analysis. Now the group actively participate in the ongoing LHC physics program ( shifts , data taking and analysis ).
After the successful start of the CMS experiment in December 2009, the first results collected at 0.9 and 2.36 TeV already indicated something surprising: the number of created particles grew faster with collision energy than expected. On 30th of March, the CMS collaboration was excited to see the first proton-proton collisions at 7 TeV, celebrating the new world record of center-of-mass energy.
The data for this study are drawn from an integrated luminosity of 1.1 μb-1 recorded with the CMS experiment on 30 March 2010, during the first hour of the LHC operation at √s =7 TeV.
Figure 1.Article header
Figure 2. Pseudorapidity distributions of charged particles compared with earlier measurements at 0.9 and 2.36 TeV.
It was found that the number of charged particles emitted in a given direction has increased by about 66% compared to the data taken at 0.9 TeV. That exceeds the predictions of many Monte-Carlo simulations and phenomenological models available by 40%, thus starting an activity geared to refine these models.
These studies are the first steps in the exploration of particle production at the new center-of-mass energy frontier, and contribute to the understanding of the dynamics in soft hadronic interactions.
Thanks to financial support of Ministry of Economy RA for possibility of visits young scientists to CERN and inclusion members of armenian group ( V.Khachatryan, A.Sirunyan, A.Tumasyan) in authors list of this important paper.
last 10 press releases:
- Educational seminars for young scientists of AANL
- Armenia become member of SCOSTEP!
- A.Alikhanyan national lab purchase high purity germanium gamma-detector for nuclear physics research and isotope production
- KHEBR laser technological complex, which is unique with its power is launched in AANL
- Ground Breaking ceremony of Nuclear Medecine Center, October 30, 2012
- Visit in Dubna, 3-4 May 2012
- National Scientific laboratory after A. I.Alikhanyan young scientist Artyom Hovhanisyan “Haykyan” award-winner.
- The prime minister visited the National Scientific laboratory after A. I.Alikhanyan
- Center for Cosmology and Astrophysics is established in A.Alikhanyan National Laboratory (AANL)
- The workshop “Low dimensional physics and gauge principles”