ICECUBE Collaboration meeting, Berkeley Markus Ackermann Status of Point Source Searches Markus Ackermann for Elisa Bernardini, Elisa Resconi, Tonio Hauschildt and Markus Ackermann
ICECUBE Collaboration meeting, Berkeley Markus Ackermann Overview Status of (time variable) point source searches A Multi-wavelength comparison B Sliding window flare search C 1ES D Future prospects (E Online filtering changes 2005 )
ICECUBE Collaboration meeting, Berkeley Markus Ackermann Multi-wavelength comparison Use information from observations of the electromagnetic spectrum to define states of high activity for a source. If EM & neutrino emission correlated better S/N ratio Defined high state by: AGNx-ray (ASM/RXTE) Microquasarradio (Ryle) Double peak structure in AGNs: high TeV emission high x-ray emission TeV photons & neutrinos are produced simultaneously in pp and p interactions
ICECUBE Collaboration meeting, Berkeley Markus Ackermann Multi-wavelength comparison very limited TeV- measurements x-ray all-sky monitor provides continuous data high state: x-ray luminosity > L L defined by optimizing S/sqrt(N) ratio (S=integr. luminosity, N=duty cycle) arbitrary relative scaling
ICECUBE Collaboration meeting, Berkeley Markus Ackermann Orphan flares Only one orphan flare known (1ES , MJD 52429) very short duration NOT included in high state period defined by x-ray luminosity independent test was taken into consideration rejected for low detection probability (short flare duration)
ICECUBE Collaboration meeting, Berkeley Markus Ackermann Results of the Multi-wavelength comparison SourceEM light curve source Livetime in periods of high activity Nr. of events in high state Expected background (high state) Expected background (4 years) Markarian 421ASM/RXTE141 d ES ASM/RXTE283 d Cygnus X-3Ryle Telesc.114 d
ICECUBE Collaboration meeting, Berkeley Markus Ackermann Results of Multi-wavelength comparison No significant excess found in high state periods Limit on x-ray/neutrino-ratio can be calculated for the selected AGN’s Full results of this analysis can be found on a dedicated web page: Will be reported in dedicated paper
ICECUBE Collaboration meeting, Berkeley Markus Ackermann Search for Neutrino flares Method presented in Uppsala & unblinding proposal event times for 12 sources unblinded point source data sample used Window size defined via detection probability investigation Calculation of significance for cluster with highest multiplicity in sliding window. events time sliding window
ICECUBE Collaboration meeting, Berkeley Markus Ackermann Search for neutrino flares Yellow Box Sliding Window containing event cluster with highest multiplicity Brown Error bars expected background for 40 days Blue lines Time of AMANDA events
ICECUBE Collaboration meeting, Berkeley Markus Ackermann Results of neutrino flare search Highest multiplicity found in any search window: 2 events SourceTotal Nr. Events (4y) Total Backgr. (4y) Search window Nr. of doublets Probability for BG fluctuation Markarian days0Close to 1 1ES days EG J days EG J days10.47 QSO days0Close to 1 QSO days10.52 Cygnus X days0Close to 1 Cygnus X days0Close to 1 GRS days EG J days0Close to 1 3EG J days20.35 GRO J days0Close to 1
ICECUBE Collaboration meeting, Berkeley Markus Ackermann Results of neutrino flare search No significant event cluster found in sliding windows for the selected sources Easy test for event clusters with relatively low trial factor Full results of this analysis can be found on a dedicated web page: Included in point source paper draft
ICECUBE Collaboration meeting, Berkeley Markus Ackermann but afterwards… comparison of the event times of 1ES with reports on TeV gamma ray flares of the source reveals that 3 of 5 events are close to its only reported period of strong TeV flare activity in detailed investigation of these events & TeV light curves
ICECUBE Collaboration meeting, Berkeley Markus Ackermann The multi-wavelength campaign May 2002-Aug 2002 TeV (WHIPPLE,HEGRA) X-ray (RXTE/PCA) Optical Radio Triggered by WHIPPLE observation TeV flux up to several Crab (average flux ~ 0.05 Crab)
ICECUBE Collaboration meeting, Berkeley Markus Ackermann The AMANDA events AMANDA – 1ES E > 600GeV WHIPPLE E > 2TeV
ICECUBE Collaboration meeting, Berkeley Markus Ackermann Looking in a larger bin 4.5 deg (95% limit of MC point spread function) 8 events in a window of 90 days expected from background : ~ 1.3 events (in 90 days) Period of multi-wavelength campaign
ICECUBE Collaboration meeting, Berkeley Markus Ackermann AMANDA events in larger bin WHIPPLE Event time / MJD Event time / MJD Event time / MJD WHIPPLE
ICECUBE Collaboration meeting, Berkeley Markus Ackermann Interpretation & Outlooks No way to state a significance for this “unblind” analysis. Chance probability: P(bg) = Even the most “unblind” chance probabilities one could calculate are far from 5 Nevertheless, even though we cannot claim any discovery it is very encouraging for future analyses Could we trigger Gamma Ray Telescope “target of opportunity” observations with neutrinos in the future ?
ICECUBE Collaboration meeting, Berkeley Markus Ackermann Future plans for 1ES A Statistically independent sample for 1ES remove events which passed our quality cuts generate & optimize new sample with new cuts another ‘blind’ search may be possible with a quantitative statistical statement BCorrelation analysis for neutrino & gamma light curves interesting method in literature (Edelson et al., ApJ 333, ) needs adaptations for our case still discussing technical issues
ICECUBE Collaboration meeting, Berkeley Markus Ackermann Other promising flares Promising events happened in 2004 which can be investigated when the data is processed: Markarian 421 possible “orphan” flare –preliminary results reported on conferences –will be investigated further huge SGR flare –10 4 times more luminous than largest gamma ray bursts –Neutrinos could be visible in AMANDA (Ioka et al., astro-ph/ ) –20 deg below horizon, but t flare ~ 0.1s Hurley et al., astro-ph/
ICECUBE Collaboration meeting, Berkeley Markus Ackermann Task for future analyses Refine the multi-wavelength approach –is it possible to include (x-ray) spectral information in period selection criteria ? –define standards (significance thresholds) for a detection/indication Refine the flare search approach –work around the arbitrary fixed window size –different type of optimization for flare search data sample?
ICECUBE Collaboration meeting, Berkeley Markus Ackermann A Neutrino alarm using online filtering Goal: Trigger ray-telescope observation of a promising source with AMANDA neutrinos (possibly increased detection chance for orphan flares) Online filtering chain completed this year at pole (details at the end of talk) Neutrino events can be filtered out in (nearly) real time (events filtered ~1h after detection) background for standard PS cuts: ~ 1-2 ev/year Telescopes could be notified with very short time lag (if SN Iridium modem is used)
ICECUBE Collaboration meeting, Berkeley Markus Ackermann A Neutrino alarm / Current status Small PERL script can do a “standard” analysis of data files: –Zeuthen PS cuts are applied to online L3 filtered data. –RA is scrambled for passing events – message containing the event data is sent (to me) FOUND EVENT AZIMUTH RANDOMIZED YEAR 2005 GPSDAY 8 MJD GPSTIME ZENITH_PANDEL AZIMUTH_PANDEL DEC_PANDEL RA_PANDEL LLHDIFF_BAYES_PANDEL PHIT_SMOOTHNESS PARABOLOID_RESOLUTION DISTANCE FROM Makarian DISTANCE FROM 1ES MAIL WAS SENT 66 MINUTES AFTER EVENT
ICECUBE Collaboration meeting, Berkeley Markus Ackermann A Neutrino alarm / Current status integration into online filtering chain at pole trivial should be tested at pole to investigate: –false alarm rate –quality of passing events –time between event &
ICECUBE Collaboration meeting, Berkeley Markus Ackermann Online filtering changes 2004/2005 NEW data stream: high quality up-going muon events. –similar to L4 from offline filtering –Additional Smoothness cut: abs(S_Phit)<0.4 –~500ev per day –contains all fits used in our PS analysis (Pandel, Bayesian, Paraboloid, Topf) –can be easily used to get the “daily neutrinos” TWR merging now done by Sieglinde
ICECUBE Collaboration meeting, Berkeley Markus Ackermann The sad part…. Do not use online filtered data from 2005 No final T0-calibration for 2005 available (muon-T0 missing) Running on 2004 T0 constants, update to 2005 preliminary constants after the meeting Not reliable because many gains/thresholds were changed Will be updated as soon as final calibration is available
ICECUBE Collaboration meeting, Berkeley Markus Ackermann Summary Flare & Multi-wavelength searches unblinded, no detection of a neutrino source neutrinos for 1ES show very interesting correlation to WHIPPLE TeV light curves. Still many things to complete on the time variability analyses 2004 data is very promising with new interesting flares