Connections Ice Cube KM 3 Ne T Christian

Connections Ice. Cube – KM 3 Ne. T Christian Spiering DESY

Content • Lessons from Ice. Cube • • „Multi-wavelength“ point source searches Network of Target of Opportunity projects Other coordinated efforts Cooperation on software and algorithms • Formal questions

Lessons from Ice. Cube (and from theoreticians) • How big a detector ? • Optimization to which energy range ? • Which configuration ?

How big a detector ? • KM 3 Ne. T: „Substantially more sensitive than Ice. Cube“ • Point sources: factor ~2 from angular resolution alone • This is by far not enough in case Ice. Cube would not have identified sources in 2010/11 • Need something like the „canonical factor 7“ – LHC upgrade (in luminosity) – 50 kt Super-K 300 kt DUSEL/Hyperkam (in volume) – Auger-South Auger North (in area) • Need much more than a cubic kilometer in volume !!

Early Ice. Cube spacing exercises • Increasing the string spacing from 100 to 180 m increases: Ice. Cube: 125 m – volume by factor 3 – 5 sensitivity by 40% • We have been reluctant to go to the largest spacing since: – String-to-string calibration may work worse. – Due to light scattering in ice the sensitivity increases much weaker than the area for large spacing. – We were optimistic w. r. t. the signal expectation. E-2

Early Ice. Cube spacing exercises • Increasing the string spacing from 100 to 180 m improves: Ice. Cube: 125 m – volume by factor 3 – 5 sensitivity by 40% • We have been reluctant to go to the largest spacing since: – String-to-string calibration may work worse. – Due to light scattering in ice the sensitivity increases weaker than the area for very large spacing. – We were optimistic w. r. t. the signal expectation. Would be no concern today Not important in water Too optimistic

Threshold for best sensitivity 1 cubic kilometer Ice. Cube Diffuse E-2 flux Blue: after downgoing muon rejection Red: after cut for ultimate sensitivity

Threshold for best sensitivity 1 cubic kilometer Ice. Cube Point sources (E-2) Blue: after downgoing muon rejection Red: after cut for ultimate sensitivity

Threshold for best sensitivity Several cubic kilometers Point sources (educated guess) Threshold between 3 and 5 Te. V ! Blue: after downgoing muon rejection Red: after cut for ultimate sensitivity

Ceterum censeo: • Optimize to energies > 5 Te. V, even if you have to sacrifice lower energies! 208 m 624 m • See original GVD/Baikal with muon threshold ~ 10 Te. V (but, alas, < 1 km³) 70 m 280 m 12 0 m 70 m

Expected flux from galactic point sources, example: RXJ 1713 -3946 (see also Paolo Lipari’s talk) Assume 0 g and calculate related ± C. Stegmann ICRC 2007

Milagro sources in Cygnus region Halzen, Kappes, O’Murchadha Probability for fake detection: • 6 stacked sources • Assumption: cut-off at 300 Te. V • p-value <10 -3 after 5 years • Optimal threshold @ 30 Te. V (determined by loss of signal events)

Aharonian, Gabici etc al. 2007 atmospheric neutrinos (green) vs. source spectra with - different spectral index (no cut-off) - index = 2 and cut-off at 1 and 5 Pe. V. normalized to d. N/d. E (1 Te. V) = 10 -11 Te. V-1 cm-2 s-1

What about the low energies when increasing the spacing? • Instrumenting a full cubic kilometer with small spacing is not efficient since for low fluxes a further increase of the low energy area will yield low-energy signal rates which are much lower than the atmospheric neutrino background rates. • Better: a small nested array with small spacing – enough „exhaust“ the potential at low energy. to • Don‘t distribute the small spacing areas over the full array but concentrate it in the center – – Better shielding No empty regions Better performance for contained events … • Deep. Core!

Ice. Cube with Deep. Core

Ice. Cube with Deep. Core VETO low-energy nested array

Early Ice. Cube Exercises

The present Baikal scenario 12 clusters of strings NT 1000: top view

Compare to KM 3 Ne. T scenarios: a c b d

Content • Lessons from Ice. Cube • • „Multi-wavelength“ point source searches Network of Target of Opportunity projects Other coordinated efforts Cooperation on software and algorithms • Formal questions

If telescopes would be only sensitive up to horizon …. Ice. Cube „blind“ Antares Baikal KM 3 Ne. T „blind“

… resulting in: point source limits/sensitivities Overlap region 25% at any given moment, 70% of Ice. Cube sky seen by KM 3 Ne. T at some moment.

Actually you can look above horizon for higher energies: +75° +60° +45° 24 h 0 h +30° -log 10 p +15° 24 h 0 h -log 10 p -15° -30° -45° R. Lauer, Heidelberg Workshop, Jan 09 ar. Xiv: 0903. 5434 Ice. Cube 22 strings, 2007

Actually you can look above horizon for higher energies: +75° +60° +45° 24 h 0 h +30° -log 10 p +15° 24 h 0 h -log 10 p -15° -30° -45° Ice. Cube 22 strings, 2007

Actually you can look above horizon for higher energies: Ice. Cube 40 strings 6 months 2008

Differential Ice. Cube sensitivity to point sources (IC-40, 1 year, 5 discovery potential, normalized to ½ decade) Taken from Chad Finley, MANTS = +30° = +6° Te. V Pe. V

Differential Ice. Cube sensitivity to point sources (IC-40, 1 year, 5 discovery potential, normalized to ½ decade) Taken from Chad Finley, MANTS = +30° = -8° = -30° = -60° = +6° Te. V Pe. V

Spectral form for extra-galactic sources Multi-wavelength analysis of individual sources ? = +30° = -60° = -8° = +60° = +6° Blazars Stecker 2005 GRB-precursor Razzaque 2008 3 Te. V 4 WB prompt GRB 5 6 Pe. V 7 BLacs Mücke et al 2003 8 9

Compare to absolute predictions Taken from Chad Finley, MANTS = +30° = -8° = -30° = -60° = +60° Crab =+22° MGRO J 1908 =+6° = +6° 3 C 279 =-6° • Predicted neutrino fluxes for a few selected sources (full lines) • IC 40 approximate 90% CL sensitivity to sources according to flux model and declination (dashed lines)

Multi-wavelength/full sky analysis • Cover 4 with 2 detectors full sky map • Add evidences/limits in overlap regions • Combine Te. V-Pe. V information from lower hemisphere of one detector with Pe. V-Ee. V information from upper hemisphere of the other detector multiwavelength analysis over 3 -5 orders of magnitude in wavelength / energy. • Need: – – Coordinated unblinding procedures Coordinated candidate source list (also for source stacking) Point spread functions Effective areas as function of energy

Alert Programs • GRB information from satellites – offline analysis, online: storage of unfiltered data & high efficiency at low E (like Antares) • Optical follow-up: telescopes robotic optical telescopes • Gamma follow-up (NTo. O): telescopes Gamma telescopes • Supernova burst alert: Ice. Cube (also KM 3 Ne. T? ) • Arguably, the ratio of signal to background alerts from telescopes is an issue. Alert programs have to be coordinated worldwide, be it only not to swamp optical/gamma telescopes with an unreasonable number of alerts.

Optical Follow-Up

Antares Optical follow-up

„Neutrino Target of Opportunity“

Alert Programs • GRB information from satellites – offline analysis, online: storage of unfiltered data & high efficiency at low E (like Antares) • Optical follow-up: telescopes robotic optical telescopes • Gamma follow-up (NTo. O): telescopes Gamma telescopes • Supernova alert (Ice. Cube) • Ice. Cube triggers KM 3 Ne. T and vice versa ? Test: Antares Ice. Cube

Presentation of WIMP results § Classes of tested models § Presentation of model parameter space § Comparison with direct searches

Other examples § GRB stacking § Combine KM 3 Ne. T/Ice. Cube GRB lists, increasing the overall sensitivity § Diffuse fluxes Any - high energy excess (extraterrestrial or prompt ) - high energy deficit (QG oscillations) should be confirmed by an independent detector, with different systematics § Confirmation of exotic events § Slowly moving particles (GUT monopoles, Q-balls, nuclearites) artefacts or reality?

Software and algorithms Framework: Mo. U between Ice. Cube and KM 3 Ne. T summer 2008 Ice. Tray KM 3 Tray Sea. Tray (now official software framework for ANTARES and KM 3 Ne. T) Improvements, debugging KM 3 Ne. T Ice. Cube Modules (future): KM 3 Ne. T Ice. Cube Simulation (event generators, air showers, …) Reconstruction methods Use of waveforms Basic algorithms (like - already now – Gulliver fitting)

Content • Lessons from Ice. Cube • • „Multi-wavelength“ point source searches Network of Target of Opportunity projects Other coordinated efforts Cooperation on software and algorithms • Formal questions

Formal framework § Memoranda of Understanding on specific items § like that on Ice. Tray § Yearly common meetings § Similar to the one we had in Berlin (MANTS) § Inter-collaboration working groups which § „synchronize“ statistical methods, ways of presentation, simulations, … (for point sources, diffuse fluxes, dark matter, …) § Global Network ? § Like LIGO/Virgo/GEO § Global Neutrino Observatory, with inter-collaboration committees ? § like Auger, CTA

Formal framework § Memoranda of Understanding on specific items § like that on Ice. Tray § Yearly common meetings § Similar to the one we had in Berlin (MANTS) § Inter-collaboration working groups which § „synchronize“ statistical methods, ways of presentation, simulations, … § for point sources, diffuse fluxes, dark matter § Global Network ? § Like LIGO/Virgo/GEO Could start this with the full community § Global Neutrino Observatory, with inter-collaboration Antares/KM 3 Ne. T, Baikal) committees(Ice. Cube, ? § like Auger, CTA

A global network ?

But first of all …. … let Ice. Cube* try to do the best it can do for KM 3 Ne. T: …see a first source ! * and ANTARES. Who knows ?

Acknowledement Part of this talk is based on talks given at the MANTS Meeting, September 2009, in Berlin. Special thanks to: § Teresa Montaruli § Jürgen Brunner § Chad Finley § Tom Gaisser, Uli Katz, Francis Halzen