Indirect Solar Search for the LKP with the IceCube 22 string and AMANDA. Detector 2007

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1 Indirect Solar Search for the LKP with the IceCube 22 string and AMANDA Detector 2007 by presented by Carlos de los Heros 1

2 KK DM / Lightest Kaluza Klein Particle LKPs promising WIMP candidates arising from theories of Universal Extra Dimensions (UED) (G.Servant02 et.al) Very few unknown parameters, unlike MSSM Narrow possible search window for the LKP mass: LKPs (B¹) couple to fermions via their hypercharges distinct annihilation channels fixed branching ratios 2

3 Analysis Outline Solar WIMP analysis for the dark year (zenith angle range 90 to ) Blind analysis with respect to the true solar direction Combined 2007 detector (IC22 + TWR Data) Personal L1+ L2 reprocessing of combined detector data Filtering optimised for LKP masses from GeV, additionally applied for 250 estimated 60 days of good data and 3000 GeV LKP Simulation: WimpAnn 2.07 WimpEvent 2.07 DarkSusy lite PYTHIA nusigma 1.14 pyr 3

4 Analysis Outline / LKP Signal Mix of different soft and hard muon spectra within 1 simulated LKP mass (e.g GeV) Cuts are designed on a weighted sum of all spectra added according to their branching ratios 4

5 Analysis Outline / LKP Signal Number of triggered signal events for core LKP masses (only trigger level) Graph All represents the weighted sum of added annihilation channels 5

6 Analysis Outline / Datasets All simulations done with IceSimV and Photonics tables AHA07v1ice (IC22) and AHA07v1ama (TWR) Reconstruction version IceRecV is used MC is used to design cuts, cut values are determined with experiment (Bg) dataset Experimet (Bg) contains of data taken after the 23/09/2007 Experiment Experiment (Bg) Single Muon Coincident Muon atm. Nu Livetime 60 d 1.54 d 1.21 d 7.08 d d 963/964 Simprod 861(IC22 only) /966 Datasets Generator dcorsika dcorsika NuGenerator Simulation of IC22+TWR coin. muon dataset was not possible at time of filtering Analysis still independent of coin. muon dataset, as cut values are determined with experiment (Bg) sample 6

7 L0 + L1 Filtering No combined 2007 detector data reprocessed by the collaboration Personally developed L0 + L1 filtering and processing as similar as possible with standard processing More restrictive cuts on first guess tracks needed to minimise data for interminable llh reconstruction L1 filters are applied in the or setting 7

8 MC vs. Experiment after L0 + L1 Sanity check after L0 + L1 filtering: All parameters used in analysis at higher filter levels are demanded to agree in MC prediction and experiment (parameter examples below) 8

9 L2 Filtering L2 Cut is similar to wimp wg (L3 cut) Single string events are excluded Cut values: 9

10 L3 Filtering Selection of horizontal tracks to minimise obvious wrong muon tracks Creating a data sample of very similar tracks (in direction and brightness) for the L4 multivariant filter level Cut values: 10

11 L4 Filtering Multivariant L4 filter level consists of a combination of 2 different TMVA routines 1 Neuronal Network (NN) trained and tested on 6 parameters Q1 1 Support Vector Machine (SVM) trained and tested on 7 parameters Q2 The L4 cut is performed on the product of the two output parameters Q1 * Q2 NN SVM Paraboloid sigma z travel rllh accumulation time l dir all n dir str b cog z n dir a l dir b n dir str (a+b+c) rho average separation Өzen, llh Өzen, first guess 11

12 Neuronal Network Input Parameters 12

13 SVM Input Parameters (only 6 parameters) 13

14 L4 Filtering In addition to cuts on Q1 and Q2, two more parameter cuts are performed to select the final sample Cut values: 14

15 Final Sample Extrapolated to 60 days of experimental data, predictions for the final sample after L4 cut are: MC Experiment More than 75% of the events are expected to be atm. neutrino events single muon 346 Currently coin. Muon 211 > 7 days atm. Neutrino 1780 processed total (60d) Trigger rates at different filter levels for all used datasets (L5 = solar search) 15

16 Filter Efficiency 16

17 L5 Filtering / Solar Search Cone Probability density functions for signal (All) and Bg of finding a certain event x within a search cone 3 methods are tested in order to find optimised MRF gives the minimum values for the nu to muon conversion rate mlkp in deg

18 Results Results for the effective Volume Sensitivity on the muon flux at detector Systematic error is so far only estimated from Gustav's IC22 analysis Calculation for a detector livetime of 60d 18

19 Results Sensitivity on the spin dependent LKP on proton scattering cross sections (90% confidence level) Theoretical predictions for cross sections depend on predictions for the mass of the KK quark 19

20 Conclusion LKP WIMP analysis using 60 days of combined 2007 detector data More than 1/8 of data is reprocessed and at final filter stage Number of experimental events in final sample agree with expected number of MC events (so far) First sensitivity for a LKP induced muon flux in the IceCube AMANDA II detector Competitive sensitivity on the spin dependent cross section of LKP on protons with only 60 days of good data With increasing instrumented detector volume and a longer data sample the combined detector will be able to explore most regions of the predicted LKP parameter space far more promising expectations than direct search experiments 20

21 Thank You for more information: 21

22 Extras / Table of Results (Core Masses) 22

23 Extras / Table of Results (Extra Masses) 23

24 Extras / Not Used Diagrams 24