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Kathryn M. Zurek University of Michigan

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Physics at the Frontiers Kathryn M. Zurek University of Michigan Wednesday, June 1, 2011 Fermilab Frontiers Wednesday, June 1, 2011 Watch (and Work) List Top AFB B physics anomalies W + jets CoGeNT/DAMA anomalies MiniBooNe Anomaly XENON and LUX below Cosmic Radiation Anomaly Higgs pole MINOS ν / ν¯ discrepancy AMS and cosmic positrons New Physics solutions require out-of-the-box models Wednesday, June 1, 2011 Watch (and Work) List Top AFB B physics anomalies W + jets CoGeNT/DAMA anomalies MiniBooNe Anomaly XENON and LUX below Cosmic Radiation Anomaly Higgs pole MINOS ν / ν¯ discrepancy AMS and cosmic positrons New Physics solutions require out-of-the-box models Wednesday, June 1, 2011 Cosmic Frontier • “Discovery” of light dark matter 3 DAMA, NaI CoGeNT, Ge CoGeNT Wednesday, June 1, 2011 FIG. 3: Low-energy spectrum after all cuts, prior to efficiency corrections. Arrows indicate expected energies for all viable cosmogenic peaks (see text). Inset: Expanded threshold re- gion, showing the 65Zn and 68Ge L-shell EC peaks. Over- lapped on the spectrum are the sigmoids for triggering ef- FIG. 4: Top panel: 90% C.L. WIMP exclusion limits from ficiency (dotted), trigger + microphonic PSD cuts (dashed) CoGeNT overlaid on Fig. 1 from [6]: green shaded patches and trigger + PSD + rise time cuts (solid), obtained via high- denote the phase space favoring the DAMA/LIBRA annual statistics electronic pulser calibrations. Also shown are ref- modulation (the dashed contour includes ion channeling). erence signals (exponentials) from 7 GeV/c2 and 10 GeV/c2 Their exact position has been subject to revisions [7]. The −4 WIMPs with spin-independent coupling σSI = 10 pb. violet band is the region supporting the two CDMS candi- date events. The scatter plot and the blue hatched region represent the supersymmetric models in [8] and their uncer- tainties, respectively. Models including WIMPs with mχ ∼7- Fig. 3 displays Soudan spectra following the rise time 11 GeV/cm2 provide a good fit to CoGeNT data (red contour, cut, which generates a factor 2-3 reduction in background see text). The relevance of XENON10 constraints in this low- (Fig. 2). Modest PSD cuts applied against microphonics mass region has been questioned [14]. Bottom panel: Limits are as described in [1]. This residual spectrum is domi- on axio-electric coupling gaee¯ for pseudoscalars of mass ma composing a dark isothermal galactic halo (see text). nated by events in the bulk of the crystal, like those from neutron scattering, cosmogenic activation, or dark mat- ter particle interactions. Several cosmogenic peaks are noticed, many for the first time. All cosmogenic prod- towards threshold that rejected events exhibit. A sec- ucts capable of producing a monochromatic signature are ond source of possibly unaccounted for low-energy back- indicated. Observable activities are incipient for all. ground are the L-shell EC activities from observed cos- 65 We employ methods identical to those in [1] to ob- mogenics lighter than Zn. These are expected to con- tain Weakly Interacting Massive Particle (WIMP) and tribute < 15% of the counting rate in the 0.5-0.9 keVee ∼ Axion-Like Particle (ALP) dark matter limits from these region (their L-shell/K-shell EC ratio is 1/8 [5]). A spectra. The energy region employed to extract WIMP third possibility, quantitatively discussed below, consists limits is 0.4-3.2 keVee (from threshold to full range of of recoils from unvetoed muon-induced neutrons. the highest-gain digitization channel). A correction is Fig. 4 (top) displays the extracted sensitivity in spin- applied to compensate for signal acceptance loss from independent coupling (σSI) vs. WIMP mass (mχ). For 2 cumulative data cuts (solid sigmoid in Fig. 3, inset). mχ in the range ∼7-11 GeV/c the WIMP contribu- In addition to a calculated response function for each tion to the model acquires a finite value with a 90% WIMP mass [1], we adopt a free exponential plus a confidence interval incompatible with zero. The bound- constant as a background model to fit the data, with aries of this interval define the red contour in Fig. 4. two Gaussians to account for 65Zn and 68Ge L-shell However, the null hypothesis (no WIMP component in EC. The energy resolution is as in [1], with parameters the model) fits the data with a similar reduced chi- 2 σn=69.4 eV and F =0.29. The assumption of an irre- square χ /dof =20.4/20 (for example, the best fit for 2 2 ducible monotonically-decreasing background is justified, mχ = 9 GeV/c provides χ /dof =20.1/18 at σSI = given the mentioned possibility of a minor contamination 6.7 × 10−41cm2). It has been recently emphasized [6] from residual surface events and the rising concentration that light WIMP models [1, 8, 9] provide a common ex- Hunt for Dark Matter • Direct conflict with CDMS Ge 3 • Neutralino from MSSM not viable 4 Ε0%0.006 Ε0%"0.006 60 60 "41 "41 "41 f "42 f %1 "42 f f %!0.7"41 1. ! 10 2. ! 10 3. ! 10 "42 1. ! 10 5. ! 10n p 2. ! 10 5. ! 10"41 n p 2. ! 10 10!39 10!36 5. ! 10"42 ∆%0 keV ∆%0 keV 1. ! 10"42 50 # 50 # 3. ! 10"42 10!40 10!37 "42 " " 2. ! 10 2 40 2 40 Β Β cm cm ! 10!41 ! 10!38 tan tan n n 5. ! 10"43 "42 Σ 30 Σ 30 1. ! 10 CoGeNT 99& CoGeNT 99& !42 !39 10 DAMA 99& 10 DAMA 99& 5. ! 10"43 XENON100 90& XENON100 90& 20 20 XENON10 90& XENON10 90& CDMS 90& CDMS 90& 10!43 CoGeNT unmod QNa%0.30 10!40 CoGeNT unmod QNa%0.30 10 10 6 8 10100 12 12014 14016 18160 180 200 6 8 10 12100 14 120 16 14018 160 180 200 m GeV m GeV Χ FrandsenmA et al. Χ mA Kuflik, Pierce, KZ FIG. 2: Constraints on the mA tan β plane from B τν, FIG. 3: Constraints on the mA tan β plane from B τν, + − → + − + → B Dτν and φ τ τ −. In the case of the B decays, we show B Dτν and φ τ τ −, and t bH . In the case of the → !→ " fn fp%!0.7 → ! " → fn fp%!0.7 → • Is10 !365-7a conservative GeV bound (grey mass shaded region): thewindow intersection10!36 of the 3 B decays, suggestive we show a conservative bound (grey shaded of region): the + sigma allowed regions for both∆%15B processes.keV For φ τ τ − (the intersection of the 3 sigma∆%15 allowedkeV regions for both B processes. For → + irregular red shaded region), the region below the curve is allowed at φ τ τ − (the irregular red shaded region), the region below the 2 σ by the Tevatron. The B-decay# region depends on the squark and curve→ is allowed at 2 σ by# the Tevatron. Since the B-decay region something10!37 gluino masses due to loop else? corrections to the b mass, so10 we!37 show the depends on the squark and gluino masses due to loop corrections to region corresponding to &0 =+&max. The region for &0 = &max the b mass, we show lines corresponding to &0 = &max. The region " + " − −+ 2 is shown in Fig. 3. The φ τ τ − is relatively insensitive2 to these for &0 =+&max is shown in Fig. 2. The φ τ τ − constraint is Wednesday, June 1, 2011 corrections. We also show→ in this plane contours of constant scatter- relatively insensitive to these corrections. The→ green shaded region cm cm ! 10!38 ing cross section, assuming the bound on the invisible! 10Z!38width (3.0 indicates the constraint from t bH+. We also show in this plane n n → Σ MeV) is saturated and &0 =+&max. Σ contours of constant scattering cross section, assuming the bound on the invisible Z width (3.0 MeV) is saturated and &0 = &max. CoGeNT 99& CoGeNT 99& − 10!39 DAMA 99& 10!39 DAMA 99& XENON100 90& XENON100 90& branching fraction and production cross section in opposite di- To conclude, acquiring a large scattering cross section in rections,XENON10 even90 extreme& values of ! = ! give rise to small XENON10 90& CDMS 90& | 0| max CDMSthe MSSM90& for light WIMPs requires a very particular Higgs !40 modifications, 5%, to these curves. Examining these!40 plots, 10 CoGeNT unmod∼ QNa%0.30 10 CoGeNTbosonunmod spectrum. To achieveQNa%0.43 the largest possible cross section we can pick out the largest allowed scattering cross section, consistent with constraints, we require µ very near its bound 6 8< 10 4212 214 16 18 6 8 10 12 14 16 18 σn 5 10− cm , below the CoGeNT allowed region. at 108 GeV, sbottoms and gluino relatively light (around 350 ∼ × If the errorsm areΧ bothGeVB experiments are inflated even further GeV),m a heavyΧ GeV right-handed stop around > 1.5 TeV, and small (both experiments taken at 3.1 sigma), a fine-tuned region at A-terms. To maximize scattering, the CP∼ even Higgs boson FIG. 1: Best-fit parameterlarger tan regionsβ opens. for DAMA There the and charged CoGeNT Higgs (coloured contribution regions) is as wellwith astan exclusionβ–enhanced limits from couplings XENON10, should be as light as possi- exactly the right size to (over)cancel the standard model con- XENON100, CDMS II and the unmodulated! " CoGeNT signal. In the upper panels, ble.δ = At 0 present, keV! and bounds"fn/fp from= 1 (left)B decays and are most constraining. fn/fp = 0.7 (right).tribution, The lower such panels that the have resultingδ = 15 sum keV is and againfn/f thep = same0.7 size (left as and right).
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