1. Compact Muon Solenoid (CMS) Physics, Status, and Plans Bill Gabella and Med Webster QuarkNet 2013 Vanderbilt University

2. 8 July 2013Gabella CMS Status2 – – The Standard Model of Particle Physics – – The Large Hadron Collider – – The Compact Muon Solenoid – – Proton on Proton collisions ● ● Higgs Boson, now your run-of-the-mill Standard Model Higgs ● ● Supersymmetry, NOT? ● ● Extra Dimensions – – Lead on Lead collisions ● ● centrality, Jet Quenching ● ● ridge in two particle correlations – – Large Hadron Collider and CMS plans Outline

3. 8 July 2013Gabella CMS Status3 Particle Physics, aka High-Energy Physics, aka Theory of Fundamental Particles Yes, but protons and neutrons are also made up of Quarks! All stable matter is made of protons, neutrons, and electrons.

4. 8 July 2013Gabella CMS Status4 The Standard Model A good description of fundamental particle interactions, relevant inside the nucleus, at early times in the evolution of the universe, and in man-made and natural collisions of particles. Particles that make up Matter. Particles that “carry” the force. All of the matter and forces in the Universe are made up of: 6 leptons (and 6 anti-leptons), 6 quarks (and 6 anti-quarks), and 12 force carrying particles...ur plus the Higgs boson and don't forget Gravity, and...

5. 8 July 2013Gabella CMS Status5

6. 8 July 2013Gabella CMS Status6 Ref: http://www.particleadventure.org

7. 8 July 2013Gabella CMS Status7 Cosmic Ray Showers Ref: http://www.particleadventure.org Mostly Protons with high energy hitting the atmosphere... make mostly muons at Earth.

8. 8 July 2013Gabella CMS Status8 Particle Accelerators Tevatron, was p on p-bar Batavia, IL (Chicago)‏ 2 TeV center of mass now lower energy, high intensity p source, also intense neutrino source L arge Hadron Collider, p on p Geneva, Switzerland 7, 8, and soon 14 TeV center of mass Ref: www.fnal.gov, www.cern.chwww.fnal.govwww.cern.ch

9. 8 July 2013Gabella CMS Status9 The Large Hadron Collider Proton-on-Proton collider, 2010-11 3.5+3.5 TeV center of mass energy 2012 4+4 TeV plan 2015 7+7 TeV also Lead-on-Lead (aka Heavy Ion) collider and Proton-on-Lead for comparison of the above two

10. 8 July 2013Gabella CMS Status10 The Large Hadron Collider

11. 8 July 2013Gabella CMS Status11 The Large Hadron Collider

12. 8 July 2013Gabella CMS Status12 Large Hadron Collider (LHC)‏ Energies: Linac 50 MeV PSB 1.4 GeV PS 28 GeV SPS 450 GeV LHC 3.5, 4, 7 TeV Ref: Introduction to Accelerators, Elena Wildner, CERN

13. 8 July 2013Gabella CMS Status13 CMS Detector http://www.uscms.org/public_2/about/cms_detector/index.shtmhttp://www.uscms.org/public_2/about/cms_detector/index.shtml Vanderbilt University (Will Johns)

14. Gabella CMS Status8 July 201314 Particles through a CMS slice

15. 8 July 2013Gabella CMS Status15 The Forward and Barrel Pixel Detector borrowed from Mauro Dinardo docdb 2404 Barrel Pixel r = 4.4, 7.3, and 10.2 cm 11520 readout chips, 48 Mpixels Forward Pixel z = +/-34.5, and +/-46.5 cm 4320 readout chips, 18 Mpixels http://www.hep.vanderbilt.edu/

16. 8 July 2013Gabella CMS Status16 CMS - Short Timeline March 2010 --- Started taking data on collisions at 7 TeV. Previous testing done at 0.45 TeV (injection energy) and 1.26 TeV. Low luminosity (intensity) 2010 - 2011 --- Taking data with increasing luminosity (intensity) by both more proton bunches in the rings and more protons in each bunch 2012 --- Running at 8 TeV, and high luminosity July 4, 2012 --- Announce discovery of Higgs-like particle, also seen with the ATLAS detector March 2013 --- Shutdown LHC and detectors for “Long Shutdown 1,” aka LS1. LHC back “on” in 2015 with energy 14 TeV.

17. 8 July 2013Gabella CMS Status17 CMS Recent Results - Higgs July 4, 2012 --- CMS and ATLAS report “Higgs-like particle” at 125 GeV. Too many H->Gamma Gamma events compared to the Standard Model predictions for the Higgs. July 4, 2013 --- The Higgs looks a lot like the Standard Model (SM) Higgs. Right ratio of different events, better statistics. Mass 125.8 GeV +/- 0.5 GeV Now measuring the quantum numbers of the Higgs: consistent with spin 0 (at least not spin 1 nor spin 2); parity consistent with +1

18. 8 July 2013Gabella CMS Status18

19. 8 July 2013Gabella CMS Status19 Higgs decays into...

20. 8 July 2013Gabella CMS Status20 Higgs to two Z's to Four Leptons borrowing from Higgs Seminar

21. 8 July 2013Gabella CMS Status21 Note the numbers... Black dots are data.

22. 8 July 2013Gabella CMS Status22 CMS (Some) Other Important Results ● Supersymmetry – Looking for “missing energy,” i.e. invisible particles, at least to the detector, as are neutrinos. – Currently appears to have eliminated many popular SUSY models; we are left with the 105 parameter full-model (maybe). ● Extra-dimensions – Inspired by Super-strings, Randall and Sundrum took the idea of extra-dimensions (spatial) seriously and asked what would accelerators see/measure. – No discovery, putting limits on the models.

23. 8 July 2013Gabella CMS Status23 CMS Heavy Ion Collisions ● LHC Collides Pb-208 ions, fully-stripped to +82 charge – in other words, atomic number Z=82, atomic mass A=208, number of neutrons N=126 ● For protons we inject at 450 GeV and ramp up to 3.5 TeV ● Acceleration is by electric field, so a charged particle with charge Ze would be injected at 450 Z GeV and ramp to 3.5 Z TeV total energy. – The bending magnets determine what energy (really momentum!) that you can have in your ring of radius rho.

24. 8 July 2013Gabella CMS Status24 CMS Heavy Ion Collisions p on p3.5 + 3.5 TeVPb on Pb287 + 287 TeV1.38 + 1.38 TeV 7 TeV c.o.m.2.76 TeV/u p on p4 + 4 TeVPb on Pb328 + 328 TeV1.577 + 1.577 TeV 8 TeV c.o.m.3.15 TeV/u (??) p on Pb4 + 328 TeV 4 + 1.577 TeV/ujust nucleons 5.02 TeV c.o.m.boosted!not at rest!

25. 8 July 2013Gabella CMS Status25 Pb-208 accounts for 52.4% of all stable lead. Z=82, N=126, A=208 CMS Heavy Ions, some numbers

26. 8 July 2013Gabella CMS Status26 CMS Heavy Ions - A tutorial well centered or glancing blow = Centrality

27. 8 July 2013Gabella CMS Status27 CMS Heavy Ions - Make a lot of Particles!

28. 8 July 2013Gabella CMS Status28 CMS Heavy Ions - Jet Quenching In a head-on collision, more Jets (q-qbar hadron shower) near the edge of the fireball. Main Jet - not modified Away Jet - highly modified Borrowed from Iancu fig 42.

29. 8 July 2013Gabella CMS Status29 CMS Heavy Ions - Jet Quenching Main Jet - not modified Away Jet - highly modified

30. 8 July 2013Gabella CMS Status30 LHC and CMS Plans Currently the LHC and all the experiments are doing maintenance. Expect to start turning on the LHC in 2015, with data taking my mid-year.

31. 8 July 2013Gabella CMS Status31 LHC and CMS Plans

32. 8 July 2013Gabella CMS Status32 Backup

33. 8 July 2013Gabella CMS Status33 Some Links/References ● http://www.particleadventure.org http://www.particleadventure.org ● Vanderbilt HEP Group http://www.hep.vanderbilt.edu/~focuser/index.phphttp://www.hep.vanderbilt.edu/~focuser/index.php ● CMS Public Talks http://cms.web.cern.ch/org/cms-presentations-publichttp://cms.web.cern.ch/org/cms-presentations-public ● CMS News http://cms.web.cern.chhttp://cms.web.cern.ch The Standard Model of Particle Physics LHC and Heavy Ions ● Ions Page http://lhc-commissioning.web.cern.ch/lhc-commissioning/commissioning-ions.htm http://lhc-commissioning.web.cern/lhc-commissioning/commissioning-ions.htm http://lhc-commissioning.web.cern.ch/lhc-commissioning/commissioning-ions.htm http://lhc-commissioning.web.cern/lhc-commissioning/commissioning-ions.htm ● LHC consolidations http://home.web.cern.ch/about/accelerators/large-hadron-collider http://home.web.cern.ch/about/updates/2013/03/lhc-consolidations-step-step-guide http://home.web.cern.ch/about/accelerators/large-hadron-collider http://home.web.cern.ch/about/updates/2013/03/lhc-consolidations-step-step-guide

34. 8 July 2013Gabella CMS Status34 Backup

35. 8 July 2013Gabella CMS Status35 Units? 1 eV...

36. 8 July 2013Gabella CMS Status36

37. 8 July 2013Gabella CMS Status37 LHC Ions, the Numbers 1/4 ● LHC Collides Pb-208 ions, fully-stripped to +82 charge – in other words, atomic number Z=82, atomic mass A=208 ● For protons we inject at 450 GeV and ramp up to 3.5 TeV ● Acceleration is by electric field, so a charged particle with charge Ze could be injected at 450 Z GeV and ramp to 3.5 Z TeV. – The bending magnets determine what energy (really momentum!) that you can have in your ring.

38. 8 July 2013Gabella CMS Status38 LHC Ions, the Numbers 2/4 ● A magnetic field B bends a charged particle with momentum P in an arc of radius. – Magnet folks like the constant "magnetic rigidity" – For the LHC ring (and the other injector rings), the B is set by power supplies and magnets and the rho by the vacuum pipe

39. 8 July 2013Gabella CMS Status39 LHC Ions, the Numbers 3/4 – So you will see people post that we are injecting at 450 Z GeV and ramping to 3.5 Z TeV for each Pb nucleus (which is a lot, 36.9 TeV injection and ramp to 287 TeV) – Okay for the physics what is more interesting is the per proton/neutron energy, so per nucleon the numbers are less 450 Z/A GeV and ramp to 3.5 Z/A TeV – Z/A is the average charge per nucleon, 0.4 e, and finally, inject at 177 GeV/u ramp to 1.38 TeV/u, and collide at 2.76 TeV/u.

40. 8 July 2013Gabella CMS Status40 LHC Ions, the Numbers 4/4 ● Bunch populations, from recent posting, – per bunch charge of 1-1.2e10... e's – Count the Pb ions at +82e each, find there are 12-14e7 Pb ions per bunch (below you will see that 7e7 is the design)

41. 8 July 2013Gabella CMS Status41 LHC Ions Injection Chain

42. 8 July 2013Gabella CMS Status42 Pixel Numerology ● Barrel has 11520 ROCs, 48 MPxl ● Forward has 4320 ROCs, 18 MPxl ● 1 ROC has 4160 pixels ● Si Sensor pixel size is 100 microns by 150 microns ● Fpix has 3 plaquette and 4 plaquette config to its panels: 3 plaquette: 2x5 + 2x4 + 2x3 (ROCs), and the 4 plaquette: 1x5 + 2x4 + 2x3 + 1x2 (ROCs) ● Urs shows fpix: (3x24+3x21)/4320 = 2.6% and bpix (3x16+6x8+3)/1152 = 0.9% not working.

43. 8 July 2013Gabella CMS Status43 LHC Ions Physics "Trivia" ● Luminosity is limited by the Electron Capture by Pair Production (ECPP) at the IPs. That is, the e- from an e+e- pair produced in the collision is captured by an Pb ion and that ion is lost on collimators leading to a vacuum problem! Limit is 0.5-1e27 cm^-2 s^-1. ● Original choice was Pb+53 after the first foil into LEAR. It was found that it had an unexpected short lifetime in the electron cooler, it picked up an e- in a much shorter time than either Pb+52 or +54. Chose +54 state. Pb+53 ends with a 5p^5 orbital---that looks bad! While Pb+52 ends with 5p^4 (all paired) and +54 ends with 5p^6. ● Beam Loss Induced Vacuum degradation in LEAR, and the creation of other charge states by Pb+54 interacting with the beam gas, led to a vacuum spec in LEAR of 1e-12 mbar (LHC can be 1e-9mbar).

44. 8 July 2013Gabella CMS Status44 The Standard Model - The Tee Shirt

45. 8 July 2013Gabella CMS Status45 The Standard Model - The Details A pretty equation for the Lagrangian Density of the quantum fields... Photons, W's, Z's bosons, gluons Electrons, Quarks, Neutrinos Higgs Particle/Field Higgs “coupled” to leptons

46. 8 July 2013Gabella CMS Status46 “ In its most explicit form, the Lagranian density of the minimal Standard Model is given by the somewhat uninspiring expression:” A. Connes & M. Marcolli gluons photons W's and Z's

47. 8 July 2013Gabella CMS Status47 Higgs Particle/Field

48. 8 July 2013Gabella CMS Status48...there is more... electrons up quarks The Standard Model - The Details

49. 8 July 2013Gabella CMS Status49 CMS Detector “ In its most explicit form, the Lagranian density of the minimal Standard Model is given by the somewhat uninspiring expression:” A. Connes & M. Marcolli Electromagnetic Fields, W's, Z's bosons Electrons, Quarks, Neutrinos Higgs Particle/Field

50. 8 July 2013Gabella CMS Status50 An Event: Higgs to 4 muons http://www.uscms.org/public_2/about/cms_detector/index.shtmhttp://www.uscms.org/public_2/about/cms_detector/index.shtml

51. 8 July 2013Gabella CMS Status51 An Event: Higgs to 4 muons