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Summary of the Multi-Messenger Astronomy Workshop Garmt de Vries Les Houches, 2002 Multi-Messenger Astronomy Workshop Organisers: D. Smith & A. Barrau 2 sessions planned 2 sessions added Goal of the workshop: To dive into the wonderful world of astrophysical catalogues!

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## Summary of the Multi-Messenger Astronomy Workshop

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**Summary**of the Multi-Messenger Astronomy Workshop Garmt de Vries Les Houches, 2002 Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**Multi-Messenger Astronomy Workshop**• Organisers: D. Smith & A. Barrau • 2 sessions planned • 2 sessions added Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**Goal of the workshop:**To dive into the wonderful world of astrophysical catalogues! Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**We play a little game:**• Imagine a 0.1 km2 detector with 3 years of data resolution ~ 1o • After subtracting the atmospheric background there is one bin with 7 events: RA = 12h 34’ δ = - 56.78o • What can this be? Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**Possible explanations**• Statistical fluctuations • Gamma Ray Burst (GRB) • SuperNova (SN) • Pulsar, SuperNova Remnant (SNR) • Active Galactic Nucleus (AGN) • SuperSymmetry (SUSY) • Microquasar • ............... Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**How to play the game?**• Look in catalogues at this place • Look for coincidence with VIRGO, HETE, AUGER, ... • Look at various models • Which model(s) can be excluded? • Which model(s) explain(s) the data best? We split up into subgroups and investigate the various hypotheses Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**Let the game begin!**Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**Statistical fluctuations**(S. Cartwright et al.) • It is known from previous experience that: • 30 bins give a background of 3 events/year • expect ~ 0.3 event/bin in 3 years • Probability of finding 7 events in this bin: 3.2 10-8 • Probability of finding 7 events in at least one of the 40,000 bins: 1.3 10-3 Probably not a statistical fluctuation Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**GRB**(S. Ferry et al.) There are 3 GRBs close to RA = 188.5oδ = - 56.78o in the BATSE catalogue: 4B950628 RA = 180o δ = -55.88o Error box radius: l = 295.72o b = 6.27o 4.93o GRB961224 RA = 182.84o δ = -64.64o Error box radius: l = 298.66o b = -2.11o 5.4o GRB971210 RA = 176.91o δ = -51.95o Error box radius: l = 293.04o b = 9.69o 1.11o Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**GRB**(continued) • Possible actions: • Send alert to SN people (GRB SN?) • Try to get timing information • Look for γ-rays • If both γ and ν observed GRB not leptonic • If no γ observed choked GRB? (look for afterglow!) Multi-messenger interplay is certainly possible Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**AGN**(N. Girard et al.) There is no quasar near RA = 188.5oδ = - 56.78o Other types of AGN have not been looked for Anyway, hadronic models predict ~ 100 times fewer ν events This hypothesis can be excluded Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**Microquasar**(S. Karkar et al.) No microquasar was seen near RA = 188.5oδ = - 56.78o This hypothesis can be excluded Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**SUSY**(S. Cartwright et al.) • One could expect a SUSY signal from: • Galactic centre • Sun • Centre of the earth None of these are close to RA = 188.5oδ = - 56.78o Perhaps a galactic halo clump? One would also expect to see ~ 10 GeV γ-rays Further investigation needed Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**Diffuse background**(A. Romeyer et al.) Yellow area: 4 detection possible It seems to be difficult to get a good signal Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**Conclusions**Our cluster of 7 events is not due to statistical fluctuations To say more, we need further information: Time Energy Other messengers Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**Neutrino Astronomy with MACRO**This paper describes exactly the game we played Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**Neutrino Astronomy with MACRO**Search for pointlike sources with clustering algorithm: Look in 1.5o, 3o, 5o around each of the 1100 muon events • 60 clusters of 4 events found in 3o cone RA δ # events 222.5o -72.7o 7 188.1o -48.1o 6 342.5o -74.4o 6 Compatible with atmospheric ν background Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**Everything is compatible with atmospheric ν background**Neutrino Astronomy with MACRO Search among known point sources: Make a list of 42 sources that look interesting Look in 1.5o, 3o, 5o around each of these sources Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**Neutrino Astronomy with MACRO**MACRO observed neutrinos from the direction of microquasar GX 339 – 4: “We notice that there are six events from GX 339 – 4 in a 3o search cone with chance probability P = 6 10-3. Considering that we have looked at 42 sources, the probability of finding such an excess from at least one of these sources is 8.6%.” Still, this source was interesting enough for our working group to investigate it Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**Microquasars**(courtesy F. Mirabel) Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**GX 339 – 4**Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**GX 339 – 4**Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**GX 339 – 4**Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**2000**Neutrinos from GX 339 – 4 Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**Neutrinos from GX 339 – 4**10/10/95 21/02/97 06/07/98 18/11/99 01/04/01 Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**The big question:**How surprising is it to see 7 neutrinos from GX339 – 4 during and after its active period? Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**Neutrinos from microquasars**Presentation by D. Guetta: Predictions of neutrino fluxes from microquasars • GX339 – 4 is one of the most powerful neutrino sources among microquasars: ~ 200 upward going muon events per year in 1 km3 However: This prediction is based on the assumption that GX339 – 4 is persistent. The active state has not been taken into account. Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**Neutrinos from microquasars**There is no a priori connection between soft X-ray activity and neutrino emission Correlation between dip in ~ 50 keV photons and neutrino emission could be understood: Source optically thick for these γ more γ present that can serve as a target for ν production But the connection is not very clear... Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**3 10-3**4 10-3 1 10-4 Statistics What is the probability of seeing these 7 neutrinos from the direction of GX339 – 4 ? Seeing 7 neutrinos during 7 years Seeing 3 neutrinos during the 450 days active period Seeing 3 neutrinos clustered in a 30 day period during 7 years Chance probability ~ few 10-3 Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**Statistics**We need the probability of finding 7 events from at least one of the sources considered: Looking at all 42 sources on the MACRO list: P 8.6 10-2 Looking only at the microquasars on the list: P 1 10-2 Looking only at GX339 – 4 and SS433, for which a high neutrino flux is predicted: P 6 10-3 But how valid is all this? Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**sees nothing**GX339 – 4 is above AMANDA’s horizon ?? ?? terrestrial gamma flashes? GX339 – 4 is visible for 19.6 hrs/day Other signals? Super-K AMANDA BATSE ANTARES Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**No active periods!**Neutrinos from other microquasars? A high flux is also predicted for microquasar SS433 (835 events year-1 km3) MACRO sees no neutrinos from this sources Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**☺**☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ Neutrinos from other microquasars? A very bold assumption: Microquasars emit neutrinos during their active state Microquasars emit neutrinos during their active state One would have to look at all the microquasars in MACRO’s field of view, and search for a correlation. Two things may happen... Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**Further ideas:**• .................................... • .................................... • .................................... • .................................... • .................................... • .................................... • .................................... • .................................... Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**To be continued...**Multi-Messenger Astronomy - Garmt de Vries - Les Houches 2002**Multi-Messenger Astronomy - Garmt de Vries - Les Houches**2002**Multi-Messenger Astronomy - Garmt de Vries - Les Houches**2002**Multi-Messenger Astronomy - Garmt de Vries - Les Houches**2002**Multi-Messenger Astronomy - Garmt de Vries - Les Houches**2002**Multi-Messenger Astronomy - Garmt de Vries - Les Houches**2002**Multi-Messenger Astronomy - Garmt de Vries - Les Houches**2002

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