IceCube: Multiwavelength Approach to Transient Neutrino Point Source Candidates http://icecube.wisc.edu Elisa Resconi, for the IceCube coll. (Max-Planck-Institute for Nuclear Physics, Heidelberg) TeV Particle Astrophysics II 28-31 August 2006. Madison, WI

106 : 1 n Fn (E, W) l 1. Construction of the Neutrino Sample IceCube event IceCube event n l 106 : 1 Fn (E, W) Elisa Resconi

Fn (E, W) = Fatm + Fgalactic + Fextra- galactic 2. Extraction of Astronomical Information Fn (E, W) = Fatm + Fgalactic + Fextra- galactic Cosmic ray showers in the Earth’s atmosphere: p, K decay  E-3.7  20% uncertainty “diffuse” flux: CR interaction with interstellar gas. “point-like”: galactic sources  E-2  ? “diffuse” flux: p decay from pg interaction with 2.7oK cosmic radiation “point-like”: extra-galactic sources  E-2  ? TeV-Blazar discussed here See also at this conference: “Implications of neutrino flux limits” J. Becker for IceCube, talk “Search for a Diffuse Flux of TeV to PeV Muon Neutrinos with AMANDA-II” J. Hodges for IceCube, poster

No significant excess found Blind analysis strategy Fgalactic(E,W), Fextra-galactic(E,W) point-like sources Ref. M. Ackermann, “The multimessenger approach ..”, Barcelona, 07.06 On-Source Off-Source = 00-04 AMANDA-II preliminary: 2000-2004 (1001 live days), 4282 n from northern hemisphere No significant excess found Blind analysis strategy Variable sources ? Elisa Resconi

dFatm(t)/dt = 1 / year 3o sky-bin Multi-wavelength approach: photon light curves used for the improvement in identify possible neutrinos emitted by astronomical sources Synthetic light curve Photon Rate (counts/sec) 2000 2001 2002 2003 1 Nr of n Time dFatm(t)/dt = 1 / year 3o sky-bin 1 n / day sky-bin ~ 310 -3 How can we discriminate these events ? What can we learn from photon observations?

3. Transient Point Sources The photon-neutrino link Access to photon data Analysis of photon data Selection of neutrino “proxy” waveband Availability / calibration / dead-time correction ….. WHAT IS A FLARE ? Elisa Resconi

3.1 The photon – neutrino link: HBL (LBL) Synchrotron proton blazar model (ref. A. Mücke et al, Astroparticle Phy, 18 (2003) 593-613) proton (highly magnetized environment) electron γ synchr. pγ γ synchr.  ,  γ γ synchr e,  γ synchr casc. (e±) γ synchr γ X LBL HBL P.Giommi et al.,A&A 445, 843-855 (2006) Elisa Resconi

X- ray band γ- ray band X- AND γ-ray  emission Interpretation Data HBL X- AND γ-ray  emission X- ray band γ- ray band C O R E L A T I N Interpretation primary electron AND secondary electron (casc.) only p, if only synchrotron (no ) Data huge amount of data, monitor + high sensitivity sporadic, no monitor, difficult to combine Strategy Light curve interpretation define “flares” define periods of high activity collect all the data available, improve definition of “flare” Elisa Resconi

3.3 Photon data: WHAT IS A FLARE ? Light Curve Interpretation: characteristic flux level(s) impulsive events (flares) statistical studies on the timescales of variability correlated activities across wavebands periods of HE neutrino emission: Construction of an hypothesis test Maximum Likelihood Blocks applied to X- and -ray light curves [E. Resconi, L. Costamante, D. Franco, E. Flaccomio, A. Gross, icecube/200608002]

X-ray: an example All-Sky-Monitor (RXTE), Mkn 421 All-Sky-Monitor, RXTE, 10 years X-ray monitor zoom Mkn 421 Elisa Resconi

All-Sky-Monitor, Maximum-Likelihood-Blocks zoom Mkn 421 Elisa Resconi

All-Sky-Monitor, Maximum-Likelihood-Blocks, Characteristic level zoom Mkn 421 Rchar Elisa Resconi

Hypothesis test: need to be blind!  sample determined a priori Time periods selected a priori  in the time periods /  atmospheric expected All-Sky-Monitor, Maximum-Likelihood-Blocks, Characteristic level zoom Mkn 421 Elevated levels or flares : ~ 15 % + 3 Rchar Characteristic level (band) Depends on: source + detector Elisa Resconi

TeV -ray: preliminary The light curves are very sporadic Compilation of historical light curves: under construction Mkn 421, Whipple public data, Maximum Likelihood Blocks Elisa Resconi

Multi-wavelength: X- vs -ray “Orphan” region Correlated corridor -ray flux “Anti-orphan” region X-ray flux, PCA (MLB blocks) Elisa Resconi

Future: … transition to a ‘multi-messengers’ approach - IceCube as a ( half ) – All-Sky-Monitor in neutrino: - Filed of view: northern sky - High duty cycle Idea: use neutrinos in order to trigger gamma-ray telescopes (see E. Bernardini, “The multimessenger approach..” Barcelona, 07.06) - Critical points under discussion: - selection of the sources: the phenomenology is limited - statistical interpretation of possible coincidences: -ray flare rate, catalogue … - blindness of the data: minimal impact with off-line analysis Status: TEST run between AMANDA and Magic of 3 months approved. Elisa Resconi

Summary Looking in the right direction and in the right moment is a good idea! From existing models: selection of proxy wavebands (HBL discussed) Photon light curves under compilation Photon light curve analysis with a global method (MLB) Selection of periods of possible neutrino emission: global & non arbitrary Next: test on the data Elisa Resconi