1. Leonid G. Levchuk -- 9th Annual CMS/RDMS Meeting, Minsk, Belarus KIPT Search for heavy Higgs in decays H  ZZ  ll  and current status of the KIPT CMS Linux Cluster L. Levchuk, D.Soroka, P.Sorokin, M. Voronko, and S. Zub Kharkov Institute of Physics & Technology, 61108 Kharkov, Ukraine

2. 2 Leonid G.Levchuk – 9 th Annual CMS/RDMS Meeting, Minsk, Belarus 30 Nov 2004KIPT Physics motivation  So far, no evidence for light (M  120 GeV/c 2 ) SM Higgs  H  ZZ  ll has ~6 times greater BR compared to H  ZZ  4l  Search for resonances in ZZ system

3. 3 Leonid G.Levchuk – 9 th Annual CMS/RDMS Meeting, Minsk, Belarus 30 Nov 2004KIPT Previous studies  N.Stepanov, CMS-TN/93-087 (1993); I.Gaines, D.Green, S.Kunori, J.Marrafino, J.Womersley, and W.Wu, CMS-TN/95- 84 (1995); …  heavy (M H >500 GeV/c 2 ) Higgs observability via H  ZZ  ll was studied  L.Levchuk et al., 6 th, 7 th and 8 th Annual RDMS/CMS collaboration meetings (2001-2003)  M H =200  250 GeV/c 2 ; ways to eliminate IB by tuning cuts to qq  Hq & gg  Hg Goals of this study   Optimization (tuning to WBF qq  Hqq, etc.) of event selection criteria for M H ~200 GeV/c 2   Extension to M H =250  450 GeV/c 2

4. 4 Leonid G.Levchuk – 9 th Annual CMS/RDMS Meeting, Minsk, Belarus 30 Nov 2004KIPT Simulation tools  PYTHIA (Ver. 6.205) u CMSJET (Ver. 4.703)   Z+jets     ZZ   ZW Background contributions “Irreducible” background 75 Mevts for 75 Mevts for Z+jets and 10 Mevts for t t have been generated _

5. 5 Leonid G.Levchuk – 9 th Annual CMS/RDMS Meeting, Minsk, Belarus 30 Nov 2004KIPT Suppression of background to H 0  Z 0 Z 0  e  e  (     ) + events _ E T miss > 30 GeV; 2 leptons such that : |  l | 20 GeV/c, p T ll >30 GeV/c, |M Z -M ll | < 5 GeV/c 2 ;  p T ll p T miss  90  (jets) ; no b-jets (p T jet >20 GeV/c); N jets  1 or 2 for p T jet >20 GeV/c, 1.0  |  jet |  4.5 For N jets  1: E T miss  40 GeV;  p T ll p T jet  120  ;  p T miss p T jet  120  ;  p l1 p l2  60  ;  p T l1 p T l2  90  ; For N jets  2: |  jet1 –  jet2 |  4.2; M jj  600 GeV/c 2 ; 2.0  |  jet |  4.5;  p T jet1 p T jet2  90  ;  jet1  jet2  0; cos(  p l1 p l2 )  0.4 “2nd level” cuts “1st level” cuts (M H = 200 GeV/c 2 )

6. 6 Leonid G.Levchuk – 9 th Annual CMS/RDMS Meeting, Minsk, Belarus 30 Nov 2004KIPT H 0  Z 0 Z 0  e  e  (     ) + vs. background _

7. 7 Leonid G.Levchuk – 9 th Annual CMS/RDMS Meeting, Minsk, Belarus 30 Nov 2004KIPT “Combined” event selection criteria

8. 8 Leonid G.Levchuk – 9 th Annual CMS/RDMS Meeting, Minsk, Belarus 30 Nov 2004KIPT “1-st level” cuts: E T miss > 60 GeV; 2 leptons such that : |  l | 20 GeV/c, p T ll > 40 GeV/c, |M Z -M ll | < 6 GeV/c 2 ; no b-jets for p T jet >30 GeV/c; no jets for p T jet >100 GeV/c “2-nd level” cuts: N jets > 0, 30 GeV/c < p T jet < 100 GeV/c Suppression of background to H 0  Z 0 Z 0  e  e  (     ) + events (M H = 400 GeV/c 2 )

9. 9 Leonid G.Levchuk – 9 th Annual CMS/RDMS Meeting, Minsk, Belarus 30 Nov 2004KIPT H 0  Z 0 Z 0  e  e  (     ) + vs. background _

10. 10 Leonid G.Levchuk – 9 th Annual CMS/RDMS Meeting, Minsk, Belarus 30 Nov 2004KIPT (current status)

11. 11 Leonid G.Levchuk – 9 th Annual CMS/RDMS Meeting, Minsk, Belarus 30 Nov 2004KIPTPerformances: 11 nodes (22 CPU’s, 38 Gflops), 2.5 TB HDD LCG Middleware: ver. LCG-2_2_0 installed and configured ver. LCG-2_2_0 installed and configured Production in 2004: 150 Kevts (CMKIN  CMSIM  HITS) generated and transferred to CERN KIPT CMS Cluster (KCC) KCC is a part of the MOSCOW Distributed RC KCC resources are allocated to CMS jobs exclusively

12. 12 Leonid G.Levchuk – 9 th Annual CMS/RDMS Meeting, Minsk, Belarus 30 Nov 2004KIPT Conclusions & plans  The results suggest that heavy (M H =200  500 GeV/c 2 ) Higgs can be observed with CMS in decays H  ZZ  ll  this has been illustrated by fast MC simulation for M H close to H  ZZ decay threshold as well as for very heavy (M H =400 GeV/c 2 ) Higgs  conclusions seem to be valid to the extent, at which one believes PYTHIA and CMSJET  use/development of an alternative generator, which would take into account 2  3 hard processes of non-resonant ZZ/ZW production is desirable u Simulations with FAMOS and (prob.) OSCAR are planned u Current status of the KIPT CMS Cluster (KCC) allows us to proceed with participation in CMS MC production  LCG-2 middleware has been installed and configured u Considerable increase of the KCC capacity is planned to provide KIPT participation in CMS data analysis  bandwidth of KIPT internet channel is still unsatisfactory; work is under way to improve the situation