Neutrino Physics with Ice Cube Ice Cube Design

Neutrino Physics with Ice. Cube • Ice. Cube Design, Status and Recent Results • Ice. Cube Potential* • Astrophysics • Particle Physics • • • Neutrino properties Atmospheric neutrinos VEP, VLI WIMPs Monopoles, Exotica • Beyond Ice. Cube • Low energy core • Ultrahigh energy radio/acoustic extensions Neutrino Physics with Ice. Cube *See AMANDA talk by B. Baret for more concrete evidence of Ice. Cube’s potential D. Cowen/Penn State 1

The Ice. Cube Collaboration University of Alaska, Anchorage University of California, Berkeley University of California, Irvine Clark-Atlanta University of Delaware / Bartol Research Institute University of Kansas Lawrence Berkeley Natl. Laboratory University of Maryland Pennsylvania State University Southern University and A&M College University of Wisconsin, Madison University of Wisconsin, River Falls RWTH Aachen DESY, Zeuthen Universität Dortmund MPIf. K Heidelberg Humboldt Universität, Berlin Universität Mainz BUGH Wuppertal Stockholms Universitet Uppsala Universitet Vrije Universiteit Brussel Université Libre de Bruxelles Universiteit Gent Université de Mons-Hainaut Chiba University of Canterbury, Christchurch Universiteit Utrecht Oxford University South Pole University Neutrino Physics with Ice. Cube D. Cowen/Penn State 2

Ice. Cube & AMANDA Site and Design • station • two tanks deployed atop each string ay nw ru Neutrino Physics with Ice. Cube 2 DOMs in each of 160 Ice. Top tanks • D. Cowen/Penn State 60 Digital Optical Modules (DOMs) on each of 70+ strings • • strings 125 m apart DOMs 17 m apart in z on string 1450 m-2450 m below surface ~1 km 3 physical volume, ~1 GTon 3

Ice. Cube Construction Status • 1320 DOMs on 22 strings Ice. Cube currently instrumented • ~0. 25 km 3 physical volume • surround AMANDA • 677 OMs deployed 19942000 Ice. Top • 104 DOMs in 52 Ice. Top tanks AMANDA photo cartoon Digital Optical Module (DOM) Neutrino Physics with Ice. Cube D. Cowen/Penn State 4

Ice. Cube Construction Status Year: Strings 2005: 1 2006: 8 2007: 13 (12 planned) 2008: 14 2009: 14 2010: 14 2011: 11+ AMANDA 01/ 2000 78 74 73 72 67 66 65 56 50 49 48 47 Ice. Cube string and Ice. Top station 01/05 59 58 57 46 40 39 38 Ice. Cube string and Ice. Top station 01/06 30 29 21 Ice. Top station only 2006 Ice. Cube string and Ice. Top station 02/07 Neutrino Physics with Ice. Cube D. Cowen/Penn State 5

How Ice. Cube and AMANDA Work • Neutrino interacts in or near the detector • Imparts energy to charged particle(s) • Charged particle(s) emit Cherenkov light • directly, and • by imparting energy to other charged particles • Cherenkov light detected by PMTs in modules in the detection medium • AMANDA OMs: analog signals, digitized on surface • Ice. Cube DOMs: digitization in situ, bits to surface • Trigger: >Nmodules hit in Dt • AMANDA: tighter spacing • Ice. Cube: quieter modules, local coincidence— more flexible trigger • Joint event triggering/building implemented this year • Filter: select events for satellite transfer north Neutrino Physics with Ice. Cube D. Cowen/Penn State 6

Ice. Cube Data Taking Status • Physics data taking since May 23, 2007 • We are running shifts (remotely) • Approaching 96% live time • Should get above 99% very soon • Event rate is ~600 Hz, acquiring 180 GB/day, over one billion events recorded so far • Detector performance is excellent • 98. 5% of deployed DOMs are commissioned and delivering physics data • 1000 DOM-years of live time accumulated thus far • 2 sensors failed after commissioning • estimated survival rate after 15 years: 97% +1. 5/-3. 5% • Fundamental parameters meet or exceed design specifications. Examples: • • Neutrino Physics with Ice. Cube individual DOM timing multi-string timing in situ LED flashers etc. D. Cowen/Penn State 7

Ice. Cube Data Quality Assurance • Example: Use in situ remotelycontrollable LEDs and downwardgoing muons to check relative DOM timing nt s e l el OM c ex D g in new m l Ti al on • DOMs have individual freerunning clocks • clocks must be calibrated to within several ns to allow us to reconstruct events • figure shows example of how this works with LEDs Neutrino Physics with Ice. Cube Dt er ov d e bl erio a st p g ar n e i m y Ti >1 D. Cowen/Penn State 8

Ice. Cube Results • Atmospheric neutrino “test beam” • Upward going atmospheric nm-induced muon sample extracted from 2006 data p n m • Note: only had 9 strings in 2006 Azimuth Zenith Residual 10% bkgd. near horizon (horiz. ) (upgoing) Saw 234 events on expectation of 255 80 Reference: ar. Xiv: 0705. 1781 v 1 (accepted by PRD) Neutrino Physics with Ice. Cube D. Cowen/Penn State 9

Ice. Cube Results • Other analyses nearing fruition: • Search for Extremely High Energy Neutrinos • One Year Ice. Cube Point Source Analysis • Please see B. Baret’s talk on AMANDA (this conference) and Ice. Cube’s contributions to ICRC 2007 for these and many other Ice. Cube/Ice. Top/AMANDA results Neutrino Physics with Ice. Cube D. Cowen/Penn State 10

Ice. Cube Astrophysics Potential • Neutrinos from cosmic accelerators • Strong circumstantial evidence that sources of high energy photons are hadronic accelerators* • Detecting neutrinos from cosmological source(s) would be ironclad evidence • p + p(g) p’s g’s and n’s • May point way to understanding origin of, and acceleration mechanism for, detected ultrahigh energy (E>~1020 e. V) cosmic rays • Possible “bottom up” astrophysical accelerator sources of UHE neutrinos (En>~Te. V): • GRBs, SNe, AGN • “Point source” analyses • Can enhance potential to discover neutrinos from transient sources with “target of opportunity” and “optical follow-up” techniques » See plenary session talk by E. Bernardini • Look also for UHE neutrino signals from diffuse sources *E. g. , HESS observation of SN remnant RX J 1713. 7 -3946; ar. Xiv: astro-ph/0611813 Neutrino Physics with Ice. Cube D. Cowen/Penn State 11

Ice. Cube Particle Physics Potential • WIMPs (a “top down” source of UHE neutrinos) • can be trapped in gravitational potential wells, annihilate, create neutrinos • • earth core, solar core, galactic center • complementary to direct detection technique AMANDA limit IC 22+A limit (anticipated) soft decay spectrum hard decay spectrum soft hard Violation of Equivalence Principle (VEP), Violation of Lorentz Invariance (VLI) • Results in measurable departures from standard neutrino oscillation expectations • linear energy dependence of oscillation frequency • Ice. Cube will do >10 x better than AMANDA-II result* Neutrino Physics with Ice. Cube • Monopoles • Exotica • Slow-moving, bright • Closely spaced upgoing track pairs (SUSY staus) D. Cowen/Penn State *presented at ICRC 2007 12

• Atmospheric neutrino oscillations • Difficult: need “low” threshold E<50 Ge. V • may be able to reach E<30 Ge. V with vertical muons nm survival probability Ice. Cube & Atmospheric n Oscillations • denser 17 m spacing in z-dimension » muon travels ~5 m/Ge. V » need at least 5 DOMs: 68 m » Em, min = 68/4 = 17 Ge. V (En, min = ~25 Ge. V) • Ice. Cube is implementing specialized low-energy trigger • Look at mup/mdown as a function of m track length » and maybe use initial creation shower to further refine measurement of E • Related idea discussed in Albuquerque and Smoot, PRD. 64. 053008 • issues: » kinematic n-m angle » ~flat inelasticity (y) distribution » cosmic ray muon background • if successful, this would be highest energy measurement of neutrino oscillations • a low energy sub-array within Ice. Cube would do a better job at this • Initial Ice. Cube study to be presented at Te. V Astro Conference in August (Venice, Italy) Neutrino Physics with Ice. Cube D. Cowen/Penn State Dm 2 = 2. 4 e-3 e. V 2 vertically upward nm En (Ge. V) m 4 x 17 m nm 13

Tau Neutrinos • At E > ~100 Te. V, nt background-free source of cosmological neutrinos • no nt from atmospheric neutrinos • oscillation effect negligible at these energies • “prompt” nt from charm decay small • only cosmological sources can give nt • Starting with ne: nm: nt: : 1: 2: 0 at source, end up with 1: 1: 1 at earth due to oscillations • Also: • • pointing resolution of nm energy resolution of ne large acceptance rich set of signatures allows systematic crosschecks • tau travels long distances (50 m per Pe. V) • tau has many decay channels • Finally… • …the total sample of nt is… 4* *DONUT Collaboration, ar. Xiv: hep-ex/0012035 Neutrino Physics with Ice. Cube D. Cowen/Penn State 14

Tau Neutrino Signatures Neutrino Physics with Ice. Cube D. Cowen/Penn State 15

Ice. Cube n Flavor Separation 550 Ge. V ne 14 Te. V ne 100 Pe. V ne downgoing m (data) 9. 5 Pe. V nt double bang D. Cowen/Penn State 77 Pe. V nt lollipop 16

Ice. Cube n Flavor Separation Neutrino flavor nt full flavor ID ne ne (supernovæ) showers vs. tracks nm 6 9 12 15 18 21 Log(E/e. V) Neutrino Physics with Ice. Cube D. Cowen/Penn State 17

Ice. Cube & Fundamental Neutrino Properties • New n or source properties distort expected 1: 1: 1 neutrino flavor ratio Source Neutrino Flavor Ratio Physics 1: 2: 0 Standard vacuum oscillations n decay (normal hierarchy) 1: 2: 0 n decay (inverted hierarchy) pure anti-ne Standard vacuum oscillations 1: 1: 1 4: 7: 7 6: 1: 1 0: 1: 1 Neutrino Physics with Ice. Cube Muon damped sources Ue 3=0; Complete decay. Current limits on n decay are weak. No initial flavor ratio can give either 6: 1: 1 or 0: 1: 1. Complicated, but flavor ID critical D. Cowen/Penn State Rachen & Meszaros astro-ph/9802280; Kashti & Waxman ar. Xiv: astroph/0507599 v 4 Beacom et al. ar. Xiv: hepph/0211305 Neutron accelerator Anchordoqui et al. , ar. Xiv: astroph/0311002 v 3 Q 13 not too small; DQ 12 and DQ 23 reduced; 10% error on flux. Optimistic… Blum, Nir and Waxman ar. Xiv: 0706. 2070 v 1 5: 2: 2 CP violation 1: 2: 0 and 0: 1: 0 References Incomplete list! 0: 1: 0 Standard vacuum oscillations Detected Assumptions Flavor Ratio /Comments 18

Ice. Cube Extensions • Low Energy (En > ~10 Ge. V) • AMANDA • closely coupled operation with Ice. Cube • coincident triggering • joint event building • combined event filtering and reconstruction • New core (just playing around with the idea…) • deploy additional strings of DOMs in closepack array deep in center of Ice. Cube • lower energy threshold, lower background » deeper, veto, specialized trigger Neutrino Physics with Ice. Cube D. Cowen/Penn State 19

Ice. Cube Extensions • High energy (E > ~10 Pe. V) • Acoustic • SPATS 06/07 • deployed 3 strings (@7 stages) • Radio Acoustic string stage being deployed • AURA 06/07 • deployed 3 clusters (@4 dipoles) (No children were co-deployed with dipoles this season) Radio cluster being deployed A possible future hybrid array Neutrino Physics with Ice. Cube D. Cowen/Penn State 20

Conclusions • Ice. Cube is functioning well with ~¼km 3 fiducial volume deployed • Began physics data taking ~1 month ago • Mother Nature willing, Ice. Cube will study fundamental neutrino properties • tau neutrinos, n oscillations, n decay, Q 13, . . • …And it can do other interesting particle physics and astrophysics • WIMPs, monopoles, other exotica • neutrinos from GRBs, AGN, SNe, … • Planning and R&D for low and high energy extensions are underway Neutrino Physics with Ice. Cube D. Cowen/Penn State 21

What Happens to Neutrinos Afterwards Mc. Murdo Station, Antarctica Neutrino Physics with Ice. Cube D. Cowen/Penn State 22