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The LHCb Experiment presented at Digital Divide and HEPGRID Workshop Rio de Janeiro, Feb 2004

Explore the concept of CP violation in particle physics and the absence of anti-matter in our universe. Learn about baryon number violations, conditions for generating CP violation, and extensions beyond the Standard Model. Discover the role of the LHCb Experiment and the quest for new sources of CP violation.

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The LHCb Experiment presented at Digital Divide and HEPGRID Workshop Rio de Janeiro, Feb 2004

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  1. The LHCb Experimentpresented atDigital Divide and HEPGRID WorkshopRio de Janeiro, Feb 2004 Tatsuya Nakada CERN and Swiss Federal Institute of Technology Lausanne (EPFL), Switzerland

  2. CP Violation We know two examples which shows matter world  anti-matter world. CP symmetry is violated !!

  3. matter anti-matter amount of matter = amount ofanti-matter our universe only with matter Evolution of Universe big bang

  4. What do we know? We see no anti nucleus in the cosmic ray. We se no g rays from pp annihilation in space. Conclusion No evidence of anti matter in our domain of universe. (~20 Mps 108 light-years) Can our universe be “inverse” Emmental Cheese? Difficult!! matter anti matter Void Most likely, no anti matter in our universe. (~3000 Mps 1010 light-years)

  5. Two key numbers stars, gas etc. Number of baryons (NB) Number of photons (Ng) = 10-9~ 10-10 cosmic microwave background radiation Number of baryons now 0 but0 NB - NB NB + NB _ = 10-9~ 10-10 _ 1 baryon out of 1010 did not annihilate and survived.

  6. How can we generate from NB- NB= 0 (initial condition for Big Bang at t =0)? NB - NB NB + NB _ = 10-9~ 10-10 _ _ Necessary conditions: 1) Baryon number violations: initial and final baryon numbers are different. 2) C and CP violation: partial decay widths are different. 3) Out of equilibrium: no reversing reaction installing the initial state. (A.Sakharov, 1967)

  7. Discovery of CP violation in particle physics: J.H. Christenson et al., PRL 1964 KL p+p-+X m(p+p-) < mK p+- = pp+ + pp- q = angle between pKL and p+- If X = 0, p+- = pKL: cos q = 1 If X 0, p+-pKL: cos q 1 q m(p+p-) = mK KL m(p+p-) > mK KL  cos q Why KL p+p- is CP?

  8. CP violation CP violation in a more intuitive way! Initial K0 p+p-CP transformation Initial K0 p+p- CPLEAR Experiment (1999) neutral kaon decay time distribution anti-neutral kaon decay time distribution

  9. CP violation BABAR and Belle Experiments (2002) similarly... t = 0 t B0 J/y KS CP B0 J/y KS

  10. How to generate CP violation? 1) Since CPT is respected, CP is like T 2) T transformation is like making complex conjugation: e-iEt T  eiEt 3) T transformation to the Hamiltonian operator H H  T  H* if HH*, e-iH t eiH*t eiH t T i.e. CP

  11. Weak interactionneutral currentcharged current: W± Up type quark spinor field Q = 2/3 Down type quark spinor field Q = -1/3 example dL u c t d s b W- U = D = Vcd coupling there are 33 = 9 V’s cL Strong interaction gluonsElectromagnetic interaction photons Standard Model and CP violation

  12. One family (u, d): V real Two families (u, d), (c, s): V real Three families (u, d), (c, s), (t, b): V can be complex Electroweak theory with 3 families cannaturally accommodate CP violation in the charged current induced interactions through the complexCabibbo-Kobayashi-Maskawa quarkmixing matrix V, with4 parameters.

  13. CP violation in the universe cannot be explained by the Standard Model. NB - NB NB + NB _ Universe: = 10-9~ 10-10 _ NB - NB NB + NB _ Standard Model: = ~10-20 _ Problem!! CP violation in the K and B meson decays can be explained by the Standard Model. New source for CP violation beyond the Standard Model in the particle world?

  14. q X complex coupling constant q New source of CP violation CP transformation containscomplex conjugation: e-iH t eiH*t i.e. H*  HCP violation X: Super Symmetric Particles, Multi-Higgs doublets, etc. Search for unexpected effects in CP violation and rare decays in Bu, Bd, Bs, Bc and b-baryons.

  15. p 7 TeV=2.710-7 cal1g of those p’s = 20 daysof US energy consumption p 7 TeV 14 TeV mini bang LHCb detector At LHC ~100 times more B mesons then before

  16. (Pre)History Study of CP violation in B meson decays with high statistics -high luminosity e+e- B factories proposed at Cornell, DESY, KEK, Novosibirsk, PSI and SLAC (since 1985…) realised at SLAC and KEK in 2000 -Idea to use high energy hadron machines as a source of B mesons CERN pp collider, FNAL pp collider and LHC At LHC three proto-experiments GAJET (internal gas target), COBEX (collider mode) and LHB (extracted fix target beam) Expressions of Interest in Letters of Intent in

  17. Joint experiment, LHCb: a forward spectrometer in collider mode b b qb b-b correlation Both b and b are in the spectrometer. b b qb Letter of Intent in August 1995: encouragement from LHCC UFRJ group joined the LHCb Collaboration in 1997 S. Amato, J.R.T. de Mello, L. de Paula, M. Gandelman, J.H. Lopes and M. Marechal The group has worked in the DELPHI experiment: -data analysis, participating in detector construction by sending people at CERN (mainly PhD students) Technical Proposal in February 1998 (S. Amato et al.) recommended for an approval by LHCC in July 1998

  18. Draft Interim Memorandum of Understanding prepared Total cost 86 MCHF (inclu. common fund 24.5 MCHF) examined by the “CORE” committee Funding discussion with the funding agencies by the participating institutes. Brazilian contribution in IMoU = 1.8 M CHF to the detector cost the detector (Muon system) + common fund with an aim to construct a part of the muon chambers and contribute to the front-end electronics. Total request to the funding agency (more than 1.8MCHF) included participation to the R&D preparing the infrastructure for the construction and test travel expense necessary for the installation, commissioning, data taking, analysis meeting at CERN. The idea was to ask for a global “project” money and manage locally.  flexibility is important!

  19. LHCb Resource Review Board (RRB) at CERN in September 1998 Most of the funding agencies expressed positively their financial contribution to the LHCb experiment Brazil: C. Aragao (UFRJ, head of the Physics Institute) Extract from the Minutes; “C. Aragao reported the result of a visit to Brasilia with B. Marechal, the Brazilian representative on the Collaboration Board. The project was presented to the President of the Research Council (CNPq) who assured them that Brazil would contribute to the Common Fund should the experiment be approved and appear to consider the 0.824 MUSD request for detector construction to be reasonable. A more detailed request was subsequently submitted for seven annual contribution of 200 kUSD giving a total of 1.4 MUSD. No final comment has been received but, at the suggestion of the President, a workshop will be held in November in Rio, at which details of the experiment and the Brazilian part of the project will be presented to members of the CNPq. It is hoped to have a clearer indication of likely participation by then. C. Aragao said that, at the present time, he was authorised to say that Brazil will participate in the Common Fund and will be studying participation in detector construction at the level indicated in IMoU.”

  20. Recommendation by LHCC and positive outcome from RRB CERN management approved the experiment in September 1998 Rio workshop on the LHCb experiment in January 1999 organized by B. Marechal sponsored by CNPq presentation by T. Nakada: physics and organization H.J. Hilke (Technical Coordinator): detector J. Christiansen (Electronics Coordinator) electronics B. Schmidt (Muon system convener) with participation by people from funding agencies (Rio and Brasilia)UFRJ management etc. • very positively received. • understanding on how high energy physics manages itself increased. • -a visit by the CNPq president to CERN in the occasion of the LHCb RRB in April 1999 discussed.

  21. LHCb magnet Technical Design Report: December 1999 Superconductive coil  Normal conductive coil 16.5 MCHF (TP)  6MCF LHCb MoU for the construction of the LHCb detector: finalised in November 2000 Detector Cost Funding expected from Brazil TP 86 MCHF ~70 MCHF 1.8 MCHF MoU 75 MCHF 73 MCHF 1.8 MCHF

  22. October 2000, Visit to CNPq Brasilia by C. Aragao, B. Marechal and T. Nakada February 2001 CBPF joined in the LHCb collaboration September 2001 LHCb Collaboration meeting was held in Ilha de Itacuruca, Brazil July 2002 Visit to CERN by the minister of State for Science and Technology Joint letter signed by the minister and DG for an extended cooperation.

  23. All the subsystem TDR’s have been approved. Computing TDR to be submitted in 2005. Detector construction advancing…

  24. Beam Pipe Al window Done by the LHC vacuum group

  25. Assembly of the lower half Plates are fixed by tie-rods Magnet Yoke Lower half completed Assembly of the sides in progress

  26. Si sensor test beam set-up Wake-field suppressor and RF foil VELO Prototype Test constructed design Construction of VELO tank support stand

  27. RICH2 RICH2 exit window being made

  28. Calorimeter SPD/Preshower production started Ecal modules: 100% constructed Hcal modules: 30% constructed

  29. Frascati Clean Room assembly tables panel on wiring machine soldering table Muon system CERN Frascati First series production chambers

  30. At the time of LHCb RRB October 2003 MoU all signed except: Brazil ??? Germany funding was guaranteed at the meeting Poland institute are receiving funding Detector Cost Funding expected From Brazil TP (1998) 86 MCHF ~70 MCHF 1.8 MCHF MoU (2000) 75 MCHF 73 MCHF 1.8 MCHF Oct. 2003 73 MCHF 71 MCHF since no clear information available we had to assume 0

  31. Brazilian contribution to theconstruction of the experiment up to now People visiting CERN, Marseille and Rome participating in the R&D, construction and testing of the experiment: PhD students Muon chambers supported by Muon Front-end electronics (VLSI) Brazil (~1 year) Muon trigger system Postdocs and Muon chambers senior scientists Muon electronics (test system) supported by Muon Experimental Control System Brazil (few weeks Core software development for to several months) and on- and offline collaboration(few weeks several months)

  32. Work done at their home institute local expertise in detector physicists Infrastructure i.e. equipped workshop and laboratories Small local funding for components CBPF Muon chamber test system Muon electronics test system Core software development UFRJ Core software development Large volume MC data production local expertise physicists with IT know-how Infrastructure small CPU cluster Small local funding for CPU

  33. data production in 2003 Using LHCb home made software tools for distributed production management. Only you need is a reasonable-good link! No special middleware required.

  34. Brazilian contribution to physics Physics performance study using MC data at home institute UFRJ by PhD students and senior physicists reconstruction of various decay modes J/y KS, J/y K*. DK* etc… reconstruction efficiency, signal over background, propertime resolution, etc… Extraction of CP violation parameters b and g Work is done in the framework of Physics Performance Task Force: short visits weekly meeting with VRVS and/or phone regular e-mail discussion many LHCb notes, LHCb reoptimization TDR, conference talk

  35. How do we plan to continue? Muon system test of the front-end VLSI chips in Rio test of the front-end cards in Italy/CERN test of wire chambers at CERN ECS development in Rio/Italy Installation and commissioning at CERN Trigger Development of High Level Trigger algorithm in Rio Development of online system software framework in Rio Computing Analysis framework software development in Rio/CERN Data production in Rio Physics study in Rio

  36. Impressive list of contribution but there are serious problems… No long term funding approved: Cannot fulfil “minimal” duty to the collaboration, i.e. annual contribution to the Maintenance and Operation cost till the end of data analysis. Difficult to under take a long term commitment. No flexible funding was available: Travel cannot be arranged with a short notice (< 3 months) Missing chances to give a talk in several conferences Cannot participate in many important meetings: However, some progress is being made here…

  37. Conclusions LHCb experiment will search for new physics beyond the StandardModel in a complimentary way to ATLAS and CMS LHCb is consciously adjusting the project to the funding situationwithout loosing physics performance Brazil has been in the collaboration since 1997. Originallyanticipated level of contribution to the detector construction (1.8 MCHF) does not seem to be realised. (MoU not signed) Despite of this difficult situation, CPBF and UFRJ groups are making well appreciated contribution in developing test systems,on and offline software, data production and physics studies. GRID is a great help but not a solution for the real problem.They still need a long term funding to cover the maintenance andoperation and trip to CERN to fully participate in the preparation,data taking, and physics analysis, i.e. exploiting their contribution(a few 100k CHF/year).

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