summary wg4 – neutrino astronomy experimental part mieke bouwhuis: results from antares georgio...
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Summary WG4 – Neutrino Astronomy experimental part
Mieke Bouwhuis: Results from ANTARESGeorgio Riccobene: Results from NEMO and KM3NeTDave Besson: Radio detectionDoug Cowen: Tau neutrino detection in IceCubeTy de Young: Novel tau signatures in neutrino telescopesJulia Becker: AMANDA flux results and interpretationElisa Resconi: IceCube: multiwavelength approach
Lutz KöpkeUniversity of Mainz
+ many posters
extend reach: (sky coverage, energy coverage, -id …)improve sensitivities: (stacking, - correlation…)
ANTARES
Mieke Bouwhuis
reconstruction with one line
full detector data taking 2007+
“typical” downgoing muons
single muon probably muon bundle
… also several upgoing muons
Zenith angle of atmospheric muons
Status of the NEMO Project
Georgio Riccobene
Capo Passero 3450 m
Toulon 2400 m
Pylos 3800:4000 m
ANTARES
NEMO
NESTOR
Advantages:
Deep, low bioluminescence, weakcurrents, little sedimentation
full tower 2007
TDR KM3NeT 2009 cost < 200 M€
NEMO-km3 detector design study
20 m
40 m
…similar number of PMT’s, towers as IceCube… 100 km from shore
Modular, rigid structures with 4 PMTs that unfolds …
Philosophy: reduce number of structures and
underwater connections; operate by ROV
Radio detection
Points of cautions: 1) presented upper limits can `float’ horizontally (no energy resolution),2) different model parameters used for different modes, 3) 90% vs. 95% C.L. limits, 4) results depend on binning
Future: Hybrid detectors(optical, radio, acoustic)
David Besson
wild ideas florish …
Europa
radio antenna
Advantages of Tau Neutrinos
appreciable flux
at source e::::1:2:0 flux rate at detector e::::1:1:1
for E > ~1 TeV low background for some topologies
atmospheric neutrino oscillation and open charm negligible …
rich set of signatures …
4acceptance at E() < ~1014-15 eV due to regeneration
very clean tag for cosmological neutrino origin !
…. but geometrically coarse detectors, low event rates, limited energy range, branching ratio …
D. Cowen & Ty de Young
detection with IceCube
: 50 m/PeV
νN interaction
decay
“classic double bang”
Learned & Pakvasa 1995
“Lollipop” – half of a double bang
Beacom, Bell, Hooper, Pakvasa & Weiler
relatively dim track
Tau topologies
..look at green topologies
….a first look
Double Pulse topology
fully simulated waveform 75 TeV (~300 TeV ):
cascade 1 cascade 2 sum MC truth
DOM Waveform
discrimination not always that obvious …
Toy-MC:Looks encouraging
needs full simulation!
ll
ll
ll
γ
e+
e-
hadronicshower
( = μ,τ)l
EMshowers
μ
Energy loss mechanisms
τ
Muons are brighter than ’s
τ
μ
→ track suddenly brightens
Can we see it?
Sugar daddy topology
track length sufficient
Ty de Young, Cowen, Razzaque, astro-ph/0608486
energy resolution
Search for single point sources
90% confidence level flux upper limits for the northern hemisphere
in 0.5 deg bins (15% systematic error included)
AMANDA: 4282 events in 5 years no significant signal limit map
improvementdue to stacking
6x 10-8 GeV cm-2 s-1
Source stacking (model-dependent!!) allows for <O(10) sensitivity improvement …
preliminary
Julia Becker
2000 2001 2002 2003
1
Nr of
Time
datm(t)/dt = 1 / year 3o sky-bin
1 / day sky-bin ~ 3 10 -3
How can we discriminate these events ?
What can we learn from photonphoton observations?
Photon Rate (counts/sec)
Time correlation studies
Elisa Resconi
Careful! Very low statistics!
test well defined hypotheses, do blind analyses, define statistical interpretation beforehand!
sample, time periods determined a priori in the time periods / atmospheric expected
intelligently select sources to monitor obtain/analyze/interpret photonic data (x-ray, gamma)
x-ray monitoring continuousTeV-gamma sporadic ….“orphans”: TeV-gamma but no x-ray
define and “code” definition of a flare reconstruct neutrino online
To turn neutrino detector to a all-sky 24/24 monitor and trigger:
3 month test AMANDA/Magic this year…
Elisa Resconi
All-Sky-Monitor, Maximum-Likelihood-Blocks, Characteristic level zoom Mkn 421
Characteristic level (band)Depends on: source + detector
Elevated levels or flares : ~ 15 %
+ 3
Rchar
TeV- curves very sporadic, historical light curves: under construction
AMANDA
Diffuse limits
112
82 108.8
srsGeVcm
E AMANDA4 year limitassuming E-2:
Hill et al., Neutrino 2006Nellen,Mannheim & Biermann 1993
Stecker & Salamon 1996 (x-ray)
Differential limits difficult to obtain limits depend on assumed spectral index
…exclude
Stecker&Salomon 96 AGN flux, but not Stecker 2005
Stecker 2005 (-ray)
Diffuse flux of TeV Blazars
conservative estimate:
Both , visible (x < 0.3)only visible (1 < x < 10)
x
diffuse flux flux sources up to redshift zmax absorption factor
Maximum contribution from TeV blazars
astro-ph/0607427
Test
spe
cific
mod
els!
Experimental summary(summary) of WG4
Extend reach:
– Northern hemisphere detectors (Antares 2007+, TDR km3NET 2009)– Further extend energy range (radio, acoustics ….)– Ideas to identify -neutrinos in many topologies
Extend sensitivities:
– stacking techniques (assume analogous behaviour, - correlation)– Correlation with x-ray or TeV flares; -telescope triggers?– Investigate specific models