Dlaczego warto szukać czegoś, co może nie istnieć?

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1 Dlaczego warto szukać czegoś, co może nie istnieć? motywacja wyniki wybór 1 Warszawa 12/14/2013 National Centre for Nuclear Research NCN grant N N

2 search fraction 2 Is it true? w o n s it' or ne ve r! If we will not find something beyond standard model in the LHC should we hope for any continuation of the highest energy collider program? s it' w o n it ' sn ow The fraction of publications with word search in the title is growing when new energy-luminosity region is probed.

3 theory experiment discovery the peasant a pig the truffles? 3

4 beyond standard model Summary (a kind of) extra structure extra particles We have searched for (almost) everything. extra interactions We have found nothing. extra symmetry We will keep searching. SUSY EXOTICA B2G Topological searches for: jets, leptons, photons, and transverse momentum imbalance 4

5 Non-SUSY searches at CMS on behalf of the CMS Collaboration VIIIth Rencontres du Vietnam Quy Nhon 17/12/2012 National Centre for Nuclear Research Warsaw, Poland International Center of Interdisciplinary Science Education 5 Jean Tran Thanh Van

6 2013 sessions in La Thuile, Aosta valley, Italy: March 2nd - 9th, 2013 EW Interactions and Unified Theories March 9th - 16th, 2013 QCD and High Energy Interactions Very High Energy Phenomena in the Universe 6

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8 Search for Narrow Resonances using the Dijet Mass Spectrum in pp Collisions at sqrt(s) = 8 TeV CMS PAS EXO particle flow wide jets R = sqrt{ η2+ φ2}< R=1.1 dijet mass 4.5 TeV 8 Trigger: HT > 650 GeV.or. dijet mass > 750 GeV & ηjj < 1.5

9 Search for Narrow Resonances using the Dijet Mass Spectrum in pp Collisions at sqrt(s) = 8 TeV CMS PAS EXO Generic upper limits on the product σ B A It can be applied to any model of dijet resonance production. Specific lower limits on the mass of string resonances, excited quarks, axigluons, colorons, s8 resonances, E6 diquarks, W and Z bosons, and RS gravitons Many extend previous exclusions from the dijet mass search technique 9

10 Search for Resonances in Dilepton Mass Spectra in pp Collisions at sqrt(s)=8tev CMS PAS EXO Relative difference between data and fitted background, (normalized to data) Background estimated using data (next slide) 10

11 Search for Resonances in Dilepton Mass Spectra in pp Collisions at sqrt(s)=8tev CMS PAS EXO Background estimate Upper limits on x-sec * BR for new boson vs Z prod. m(z') > 2590 GeV; superstring-inspired m(zψ) > 2260 GeV 11

12 Search for microscopic black holes at sqrt(s) = 8 TeV with the CMS detector CMS PAS EXO Trigger: HT fit window fit window ST scalar sum of the transverse momenta of individual objects( with pt > 50 GeV): jets, electrons, photons, muons and missing ET all such objects except missing ET are counted towards the final-state multiplicity N 12

13 normalization normalization normal. ST multiplicity invariance method at work 13 normalization

14 Search for black holes 14

15 Dimitri Denisow, Exp. summary, March 16,

16 sbottom-bottom 16

17 stop-top 17

18 Search for electroweak production of charginos, neutralinos and sleptons using leptonic final states in pp collisions at s = 8 TeV ewkino models 18

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23 a dark matter puzzle 23

24 AMS-02 (3 April 2013) High quality result from excellent experiment No discovery whatsoever Dangerous publicity In (not only) my opinion Do not ask what cosmology can do for you... 24

25 Search for dark matter at LHC via ISR. Search for Dark Matter and Large Extra Dimensions in pp Collisions Yielding a Photon and Missing Transverse Energy; arxiv: , Phys. Rev. Lett. 108 (2012) Search for dark matter and large extra dimensions in monojet events in pp collisions at sqrt(s) = 7 TeV; arxiv:

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27 Ograniczenia CMSSM (2011) 27

28 m1/2 So where is au t s (N? SP L )?? LHC lim it Are we sure that levelling is the best way to search for a golf ball? 28 m0

29 Isn't long lived creatures interesting? 29

30 Heavy quasi-stable Charged Particles Flying through lepton like (stau) R-hadrons fractional charge mulitple charge Stopped in the detector R-hadrons HSCPs - heavy quasi-stable charged particles (or CHAMPs charged massive particles ) are hipotetical objects that appear in various extensions of the standard model (SM) in which gravitino or axino plays the role of the LSP, as well as in other BSM extensions arising from a new symmetry, a weak coupling, a kinematic constraint, or a potential barrier muon, stau R-hadron 30

31 Stopped HSCP R-hadrons are hadronized semi-stable gluinos or squarks (stops, sbottoms) predicted by split-susy (among others). These particles have relitivelly large probability to stop in the detector. detector Stopped in the detector R-hadrons stopping probabilty stopping points stopped gluino muon, stau asynchronous decay R-hadron 31

32 Trigger + offline veto & cleaning Beam-halo background Jet trigger in coincidence with no beam condition: 32 GeV E threshold at L1 and 50 GeV at HLT T veto both BPTX (beam position and timing) +-1 BX η < 3 veto L1 endcap beam halo trigger (+-1 BX) Offline veto: veto +-2 BX any beam activity (at BPTX) veto any reconstructed beam halo event (any muon like signal in the forward muon syst. CSC) veto any event with primary vertex veto any event with at least 1 muon (or at lest 2 signals in the barrel muon syst. DT or RPC) Cleaning and noise rejection: standard cleaning and noise rejection η < 1 reconstructed jet energy > 70 GeV spacial distribution of the deposits requirements pulse time shape requirements Background estimate cosmic rays background by MC (validated by real data) beam-halo by tag & probe (two endcaps) noise using 2010 control sample 32

33 Stopped HSCP 95 % CL X-sec limits (top) & mass limits (bottom) as a function of lifetimes The structure visible for small lifetimes is due to time window 1.3*τ used for lifetimes shorter than LHC orbit (89μs). Table: Results of countig experiments (Nexp background events) 33

34 complementarity R-hadron stopping flying through If the lifetime of HSCP is longer than a few nanoseconds, the particle will flight through detector. It clould be regarded as stable from the detection point of view 34

35 The idea of the HSCP search Exotica, or search beyond detector design. de/dx in tracker ECAL and HCAL time delay from pulse shape ECAL, HCAL, CSC time delay from hits scatter in DT BX change in RPC 35

36 TOF DT method time delay from hits scatter in DT BX change in RPC 36

37 Muon System 37

38 DT: invers beta 38

39 DT: invers beta 39

40 DT: invers beta 40

41 DT: invers beta 41

42 TOF by the muon system Relation between candidate velocity and the time delay delta_t at a distance L. The third idependent measurement (if aplicable). 42

43 Time in the RPC Arcs represent aproximate delay time surfaces for a HSCP with beta ~ ns, 25 ns & 37.5 ns 43

44 RPC HSCP Behavior of the RPC trigger and its influence on the data read by the DAQ HLT - data read by the DAQ L1 HLT L1 HLT L1 L1 L1 - bit in the PAC for the LAST RPC layer BX of the time of: - hit in the LAST RPC layer - bit in the PAC for the 1st RPC layer - hit in the 1st RPC layer - hits in the tracker time measured in BX BPTX bit BPTX bit BPTX bit BPTX bit BPTX bit BPTX bit BPTX bit PAC Pattern Comparator is the logic of the RPC trigger 44 muon HSCP late cosmic

45 Effect of RPC trigger change 45

46 The idea & trigger HSCP could be slow enough to be late with respect to relativistic muons; give higher de/dx than MIPs. Two strategies for flying through HSCPs: tracker only (de/dx only) analysis; tracker + TOF in the muon system analysis. muon, stau R-hadron 2011 analysis 46 Triggers: MET (particle flow) > 150 GeV single muon p > 30 GeV/c T special BX0+BX1 muon trigger (RPC)

47 de/dx in tracker An estimator: via relation: K = MeV cm-1 c-2 C = MeV cm-1 is used to estimate the mass of the HSCP canadidate, whereas value of a discriminator: is used to obtain signal and control regions. Pi is the probability that MIP will give signal smaller than recorded for a given hit i. 47

48 2012 analysis 48

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52 Results 52

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55 BooMerang (& other ideas) Backward off-time off-point Muons outline Motivation search for HSCP muon decays (stau NLSP); HSCP lifetime determination; sensitive to LSP mass; spin-off: cosmic veto, CMS as an upward neutrino detector, etc. How? muon flight direction by RPC at L1 by using spare RPC trigger hardware; a duplicate of the TTU RPC trigger; information form the whole barrel (not wheel based); trigger on upward muons only (to reject cosmics). Pros: complementary to calorimetric stopped gluino search; sensitive also to HSCPs stopped in the iron yoke; off-beam inter-wheel cosmic trigger possible; shower in the ECAL due to cosmic veto (?). 55 Cons: low geometric efficiency :-( impossible to add forward RPC (without an upgrade). or water? Xenon? Argon?

56 John N. Bahcall and Raymond Davis, Jr

57 Conclusions We (CMS) have not yet found any exotic beast, but we keep searching. St au NL S P 57