LHCb status. Raluca Mureşan EPFL. p.1/20

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1 LHCb status Raluca Mureşan EPFL p.1/20

2 Disclaimer too many things going on 8 meetings to attend per week, days with over 100 s very dinamic evolution - the most of the plots shown in a meeting are alreay outdated deeply involved (150% of my working time) in the first data analysis not clear if to show or not own work Appologies in advance for a rather biased (analysis based), incomplete, outdated presentation. More about physics analysis than about hardware... p.2/20

3 LHCb 730 members 15 countries 54 institutes 17 February 2010 LHCC open session Andreas Schopper 1 R. Mures an LHCb status p.3/20

4 LHCb detector y Dedicated b-physics experiment: CP violation and rare decays 5m Vertex Locator TT Magnet T1 T2T3 RICH2 ECAL SPD/PS M1 HCAL M2 M3 M4 M5 Forward single arm spectrometer - large and correlated b b quark production in the forward region. 5m 10m 15m 20m z Coverage: (250) mrad p.4/20

5 LHCb detector y 5m Magnet RICH2 ECAL SPD/PS M1 HCAL M2 M3 M4 M5 T1 T2T3 Vertex Locator TT 5m 10m 15m 20m z p.4/20

6 What happened... Steve 100th LHCC meeting p.5/20

7 What happened... Date recorded ~6 µb -1 of integrated luminosity with Minimum Bias trigger (L0: HCAL&SPD -OR- muon -OR- backward VELO planes ) total of ~ pp-collision events at 450 GeV (beam gas subtracted) with all detectors ON and VELO powered (stable beams!) Number of crossing On disk Number of beam-beam crossing On disk Number of beam1-gas crossing On disk Number of beam2-gas crossing On disk Estimated Number of pp interaction on disk pp interaction / (bbcrossing) Estimated L0 rate (t=0) L0 rate (t=0) pp interaction rate (t=0) [Hz] beam1-gas crossing [Hz] beam2-gas crossing [Hz] Recorded luminosity [ b -1 ] Dec 6, % Dec 6, % Dec 8, % Dec 9, % Dec 11, % Dec 11, % Dec 12, % Dec 12, % Dec 12, % Dec 15, % Dec 15, % February 2010 LHCC open session Andreas Schopper 3 p.6/20

8 What happened.. We run with VELO partially open Commissioning of LHC detector and trigger done in parallel = not so easy to get physics results. p.7/20

9 A glimpse to the first data K s and Λ 450 GeV/beam m π + π (LHCb 2009 data, preliminary) - m p +/- -/+ π (LHCb 2009 data, preliminary) candidates/2 MeV Integral χ / ndf / 64 Prob constant ± 1.41 slope ± N signal ± 41.3 m ± 0.14 narr σ m ± candidates/1 MeV Integral χ / ndf / 82 Prob constant ± 15.2 slope ± N signal ± m ± 0.1 narr σ m ± DATA [MeV] K s m π + π (LHCb 2009 MC, preliminary) - m π + - π m p +/- -/+ π [MeV] Λ (LHCb 2009 MC, preliminary) m +/- p -/+ π candidates/2 MeV Integral 825 χ 2 / ndf / 27 Prob constant ± slope ± N signal ± m ± 0.16 σ narr m ± candidates/1 MeV Integral χ / ndf / 38 Prob constant ± 4.23 slope ± N signal ± m ± 0.2 narr σ m ± MC [MeV] m π + - π [MeV] m +/- p -/+ π p.8/20

10 A glimpse to the first data π 0 and η p.9/20

11 A glimpse to the first data Φ and RICH no PID PID p.10/20

12 LHCb 2009 Unique rapidity range (2<η<5), unique energy. Important input for tuning Monte Carlo. Topics pursued: Charged track multiplicities and p t η distributions Measurements of K s and Λ cross sections as function of p t and η Ratio of strange meson over strange baryon production Ratio of Λ over Λ production p.11/20

13 Pseudorapidity range Studies of the inclusive distributions at LHCb particularly interesting because of the unique rapidity range coverage. ATLAS CMS+TOTEM ALICE LHCb tracking, ECAL, HCAL, counters lumi, muon, hadron PID Pictures from Tara Shears talk: p.12/20

14 Why V 0 LHCb 2009? Strange particles - enough statistics to make a study using the 2009 data if we define our problem properly. Understanding and calibrating our detector Tracking studies, RICH calibration, even more important: a complete analysis exercise giving an insight of what one needs for a successful analysis MC tuning and validation Compare the distributions we see in data and MC, few V 0 distributions can be used to discriminate between generator models. Stepping stone towards reconstruction of interesting charm and beauty hadrons that have as daughters K S, Λ,..., in particular for charm and beauty baryon studies (Λ) beauty baryons out of reach for the b-factories. QCD physics studies p.13/20

15 Models disagree wildly. Don t listen to them N( (Still, can be used to gauge 0.8 possible size of effect) bar)/n( 0 ) GeV p+p Inelastic, Non-Diffractive 0 bar / 0 Distribution (generator-level) Perugia 0 Perugia HARD Perugia SOFT Perugia NOCR DW Pythia Wednesday, January 27, p.14/20

16 Why V 0 LHCb 2009? The low-energy LHC runs give us a unique chance to fill in the gaps in our knowledge at lower energies Highest energy pp data RHIC 200 GeV How about Tevatron? -> central detector η < 1, p p N(Λ 0 bar)/n(λ 0 ) GeV p+pbar Inelastic, Non-Diffractive Λ 0 bar / Λ 0 η Distribution (generator-level) Perugia 0 Perugia HARD Perugia SOFT Perugia 3 Perugia NOCR Perugia LO* Perugia 6 N(Λ 0 bar)/n(λ 0 ) GeV p+pbar Inelastic, Non-Diffractive Λ 0 bar / Λ 0 η Distribution ( η <1.0, p >0.4GeV) Perugia 0 Perugia HARD Perugia SOFT Perugia 3 Perugia NOCR Perugia LO* Perugia 6 CDF 1 1 Pythia Pythia η η skands/leshouches-plots p.15/20

17 What else? detector preparation for the 2010 run tracking and alignment improvement (Reco 8) on the way MC tuning - cross-experiment effort Already 24/24 h, 7/7 days shifts: cosmics also TED run at the end of the last week. Collisions at 3.5 TeV still forseen around mid-march. p.16/20

18 LHC plans Two possible scenarios: Run at 3.5 TeV/beam up to a defined integrated luminosity with a day limit, afterwords consolidate the whole machine for the 7 TeV run minimum risk; more efficient over the LHC lifetime. run until second half of 2010 then do minimum repair to allow 5 TeV/beam in 2011 (7 TeV much later) higher risk; reduce running in 2010, long shutdown , delays operation at higher energy. Will go for scenario 1 p.17/20

19 Scenario A: sort splices out in one go Two years at 3.5 TeV 2010: should peak at and yield up to 0.5 fb : ~1 fb -1 at 3.5 TeV 2012: splice consolidation (and cryo collimator prep.) 2013: 6.5 TeV - 25% nominal intensity 2014: 7 TeV 50% nominal intensity Aggressive Year Months energy beta ib nb Peak Lumi Lumi per month Int Lumi Year Int Lumi Cul e e e e e e e e /01/10 LHC luminosity estimates 66 p.18/20

20 Physics in 2010 With L > 200 pb -1, expect to make significant contributions in all channels of our physics program, with particularly exciting possibilities in: B s µ + µ - B s J/ B 0 K*µ + µ - charm physics Keys for success High precision tracking close to the production vertex Muon identification and K/ separation over a large momentum range High selective trigger, efficient and flexible With 2009 data, started to exercise the analysis methods and investigate performances. As an example: B S µ + µ Thomas Ruf LHCb Status Report 100 th LHC Session 17/02/ p.19/20

21 Summary 2009 detector performance in many areas already in good agreement with MC expectations. Expect to see improvements with new detector alignments Prospects for interesting physics results with 2009 data Waiting eagerly for 3.5 TeV to be able to close Velo and have final detector configuration. Looking forward to the 2010 run physics results. p.20/20