Carlos de los Heros , Uppsala University
description
Transcript of Carlos de los Heros , Uppsala University
Carlos de los Heros, Uppsala University
results from neutrino telescopes
COSMO05. Bonn, Aug. 28 – Sep. 1, 2005
Outlook.
as a framework: high energy neutrino astronomy
the world of neutrino telescopes: current projects
recent physics results from AMANDA and Baikal
ICECUBE: status and capabilities
summary
• nature accelerates particles to ~10 7 times the CM energy of LHC!
acceleration sites must sit somewhere
candidate sources:• SNe remnants, quasars• active galactic nuclei• gamma ray bursts
neutrino astronomy
? proton accelerators
guaranteed sources:• atmospheric neutrinos (from & K mesons decay)
• galactic plane: – CR interacting with ISM, concentrated on the disk
• CMB (diffuse):– UHE p + n + (p 0)
T. Gaisser 2005
particle propagation in the Universeproduction:neutrino production at source: p+ or p+p collisions give pions: e- + e
neutrino flavors: e : : 1:2:~0 at source. Expect 1:1:1 at detector
propagation:photons: can be absorbed on intervening matter or radiation;protons: deviated by magnetic fields
at high-enough energies: p and react with the CMB bckgr.
’s will get to you
however: ’s extremely difficult to detect!
your favourite cosmic accelerator
p
your favourite detector
Outlook.
as a framework: high energy neutrino astronomy
the world of neutrino telescopes: current projects
recent physics results from AMANDA and Baikal
ICECUBE: status and capabilities
summary
current HE neutrino detection effortscurrent HE neutrino detection efforts
OPTICALOPTICALRADIORADIOACOUSTICACOUSTIC
@ extremely high energies (E>1018 eV)
AMANDA / ICECUBEAMANDA / ICECUBE
NEMONEMO NESTORNESTOR
BAIKALBAIKAL
RICE, ANITARICE, ANITA
SALSASALSAKAMCHATKAKAMCHATKA
AUTECAUTECGLUEGLUE
ANTARESANTARES
SADCOSADCO
neutrino detection in ice/water
7.0)TeV/(7.0 E
longer absorption length → larger effective volumelonger scattering length → better pointing resolution
event reconstruction by Cherenkov light timing: need array of PMTs with ~1ns resolution
optical properties of the medium of prime importance
absorption length scattering length
South Pole ice(AMANDA/IceCube)
110 m (@ 400nm) 20 m (@ 400nm)
Lake Baikal 25 m (@ 480nm) 59 m (@ 480nm)
Mediterranean(ANTARES/NESTOR) ~60 m (@ 470nm) 100-300 m (@ 470nm)
neutrino astronomy possible since
O(km) long muon tracks
O(10m) cascades, e neutral current
signatures
the BAIKAL detectorthe BAIKAL detectorNT-200- - 8 strings with 192 optical modules- - 72 m height, 1070 m depth- - effective area >2000 m2 (E>1 TeV)
- - Running since 1998
NT-200+- - commisioned April 9, 2005.- 3 new strings, 200 m height- 1 new bright Laser for time calibration imitation of 20TeV-10PeV cascades, >10^12 photons/pulse w/ diffusor,- new DAQ- 2 new 4km cables to shore
4 Km to shore NT200+ is tailored to UHE -induced cascades 5 Mton equipped volume; V_eff > 10 Mton at 10 PeV
PMT noise: ~1 kHz
Optical Module
the AMANDA detector
AMANDA-B10- - 10 strings with 302 optical modules- - 450 m height, 1500 m depth- - data years: 1997/99
AMANDA-IIAMANDA-II- 19 strings, 677 OMs- running since 2000 - new DAQ with FADC since 2003
since March 2005 we are called IceCube!
(AMANDA and IceCube collaborations merged)
Amundsen-Scott South Pole station
South Pole
Stationfacilities
AMANDA
your daily commute to work
1500 m
2000 m
the site
[not to scale]
muons:directional error: 1.5° - 2.5°(log(Ereco/Etrue)): 0.3 – 0.4coverage: 2
cascades: (e±, , neutral current)zenith error: 30° - 40° (log(Ereco/Etrue)): 0.1 – 0.2
(5TeV < E < 5PeV)coverage: 4
effective area: >10000 m2 for E>1TeV
AMANDA detector performance
Average upper limit = sensitivity (δ>0°)
(integrated above 10 GeV, E-2 signal)
aver
age
flux
uppe
r lim
it [c
m-2s-1
]sin
AMANDA-B10
AMANDA-II
tim
e
Outlook.
as a framework: high energy neutrino astronomy
the world of neutrino telescopes: current projects
recent physics results from AMANDA and Baikal
ICECUBE: status and capabilities
summary
in this talk:
• AMANDA (and Baikal when available) results from:
atmospheric neutrinos
searches for an extra-terrestrial flux: galactic centerdiffuse (anytime, anywhere)point source (anytime, somewhere)transient (known ‘flary’ objects & GRBs) (sometime, somewhere)
search for WIMPs: Excess from the center of the Sun/Earth
agreed AMANDA collaboration strategy: analyses are done ‘blind’. cuts optimized on a % of data or on a time-scrambled data set.
EHadron E-2.7 0.02
cosmic ray muonstest beams: atmospheric muons
SPASE (scintillator array @ 3000m) e density @ surface shower core resolution: 0(m) shower direction resolution: < 1.5o
AMANDA ‘s @ >1500m (>300 GeV @ surface) use SPASE core position for combined fit
combined SPASE-AMANDA ‘detector’:
probes hadronic () and EM (e) component of the primary shower(E) ~ 0.07 in log(Eprim)
results compatible with composition change around the knee
sources of systematic uncertainties:(~30% in ln(A), not shown in the plot) -shower generation models -muon propagation
atmospheric muons: - AMANDA test beam: I vs depth, CR composition - background for other searches
set limit on cosmic neutrino flux:
how much E-2 cosmic ν - signalallowed within uncertainty of highest energy bins?
limit on diffuse E-2 νμ flux (100 -300 TeV):
first spectrum > 1 TeV (up to 300 TeV)- matches lower energy Frejus data
E2μ(E) < 2.6·10–7 GeV cm-2 s-1 sr-1
test beams: atmospheric neutrinos
vertical
horizontal
Frejus
AMANDA
► reconstruct energy of up-going μ`s► obtain energy spectrum from regularized unfolding
atmospheric neutrinos: - guaranteed test beam - background for other searches
on-source region
on-source events
expected background
90% event upper limit
line source limit
GeV-1 cm-2 s-1 rad-1
diffuse limitGeV-1 cm-2 s-1 sr-1
gaussian limit
GeV-1 cm-2 s-1sr-1
2.0º 128 129.4 19.8 6.3 10-5 6.6 10-4 —4.4º 272 283.3 20.0 — — 4.8 10-4
-------
Gaus. limit
model
’s from the galactic plane
• location of AMANDA not optimal reach only outer region of the galactic plane: 33o<<213o
• three signal ansatz:line source, Gaussian source, diffuse source
• limits include systematic uncertainty of 30% on atm. flux
• energy range: 0.2 to 40 TeVdata sample 2000-03: 3369 evts:
strategies in the search for point sources:
•diffuse flux with no time-space correlations. •from high energy tail of atmospheric νμ
• selection with emphasis on background(s) rejection
•spatial correlation with steady objects•search for clusters of events (w. or w.o. catalogue)•stacking of same-type of point source candidates
•space and/or time correlation with transient phenomena
•known active flary periods of TeV gamma sources•coincidence with GRBs
search for HE neutrinos from the cosmos
UHE: E > PeV
•Earth opaque: search in the upper hemisphere and close to the horizon
HE: TeV < E < PeV
•search confined to up-going tracks
analyses optimized for
(reduced sensitivity to e and )
Cascades: TeV < E < PeV
• 4sensitivity
all-flavour
energy regions:
diffuse flux search
AMANDA1: B10, 97, ↑μ2: A-II, 2000, atmosph. 3: A-II, 2000, cascade4: B10, 97, UHE6: A-II, 2000, UHE sensit.7: A-II, 2000-03 ↑μ sensit.
Baikal5: 98-03, cascades8: NT200+ sensitivity to e
limits for other flux predictions: - cuts optimized for each case. - expected limit from a given model compared with observed limit.
some AGN models excluded at 90% CL: Szabo-Protehoe 92. Proc. HE Neutr. Astrophys. Hawaii 1992. Stecker, Salamon. Space Sc. Rev. 75, 1996 Protheroe. ASP Conf series, 121, 19971:1:1 flavor flux ratio
all-flavor limits
67 8
event selection optimized for both dN/dE ~ E-2 and E-3 spectra
search for clusters of events in the northern sky
sourcenr. of events
(4 years)
expectedbackgr.(4 years)
flux upper limit 90%(E>10 GeV)
[10-8cm-2s-1]
Markarian 421 6 5.58 0.68
1ES1959+650 5 3.71 0.38
SS433 2 4.50 0.21
Cygnus X-3 6 5.04 0.77
Cygnus X-1 4 5.21 0.40
Crab Nebula 10 5.36 1.25
data from 2000-2003 (807 days)
3369 from northern hemisphere
3438 expected from atmosphere
• search for excesses of events on:
• the full Northern Sky
• a set of selected candidate sources
significance map
… out of 33 Sources
crab
Mk421Mk501
M87
Cyg-X3
SS433
1ES1959
Cyg-X1
neutrino sky from Baikal
1998-2002 data sample - 372 events - 385 evts expected - no indication of clustering
• catalogues: BATSE+IPN3
• bckg. Stability required within ±1 hour from burst• several search techniques:
• coincidence with T90• precursor (110s before T90)• cascades (all flavour, 4)
-coincident with T90-rolling time window (no catalogue)
search for ’s correlated with GRBslow background
analysis due to both space and time
coincidence search!
year # GRBs from
preliminary 90%CL upper limitassuming WB spectrum (EB at 100 TeV and = 300)
'97 - '00 312BATSE
triggered bursts
E2d/dE = 4 · 10-8 GeV cm-2s-1 sr-1
'00 - '03 139 BATSE & IPN bursts E2d/dE = 3 · 10-8 GeV cm-2 s-1 sr-1
'01 - '03 50 IPN bursts (Assuming the Razzaque model)E2d/dE = 5 · 10-8 GeV cm-2 s-1 sr-1
'01 (425) Rolling window E2d/dE = 2.7 · 10-6 GeV cm-2s-1sr-1
'00 73BATSE
triggered bursts
E2d/dE = 9.5 · 10-7 GeV cm-2s-1sr-1
10 min1 hour 1 hour
110 s T90 time
Off-TimePrecursor On Time
Always Blind
• m 20%, b 5%
non-baryonic matter
MSSM candidate: the neutralino,
may exist as relic gas in the galactic halo
gravitational accumulation in Sun/Earth makes ‘indirect’ searches with neutrino telescopes possible
search for DM candidates in the Sun/Earth
neutralino-induced neutrinos: qq
l+l- W, Z, H
signature: excess from Sun/Earth’s center direction
A lot of physics (ie. uncertainties) involved: - relic density calculations - DM distribution in the halo - velocity distribution - properties (MSSM) - interaction of with matter (capture)
2001
Sun analysis possible due to improvedreconstruction capability for horizontal tracks in AMANDA-II compared with B10.
search for a neutralino signal from the Earth
search for a neutralino signal from the Sun
results from indirect DM searches
e.g. magnetic monopoles:
Cherenkov-light (n·g/e)2
(1.33*137/2)2
8300 times brighter than ‘s!
signature: ‘slowly‘ moving bright particles
other particle searches
10-16
10-15
10-14
10-18
10-17
= v/c1.000.750.50
uppe
r lim
it (c
m-2 s
-1 s
r-1)
KGFSoudan
Baikal 2005
Amanda-B10
1 km3
electrons
MACROOrito
Outlook.
as a framework: high energy neutrino astronomy
the world of neutrino telescopes: current projects
recent physics results from AMANDA and Baikal
ICECUBE: status and capabilities
summary
deep ice array: IceCube
digital readout technology (DOMs) 80 strings, 60 DOM’s each 17 m DOM spacing 125 m between strings hexagonal pattern over 1 km2x1 km
1200 m
the IceCube observatory: IceCube+IceTop
IceTop
IceCube
surface array: IceTop 80 stations air shower array
(one per IceCube string) similar station concept as Auger 2 tanks (2 DOMs each) per station 125 m grid, 1 km2 at 690 g/cm2
E=6 PeV
IceCube: an all-flavor neutrino telescope
•IceCube will be able to identify - tracks from for E > 100 GeV - cascades from e for E > 10 TeV - for E > 1 PeV
•background mainly downgoing bundles(+ uncorrelated coincident 's)
- exp. rate at trigger level ~1.7 kHz- atm. rate at trigger level ~300/day
e e “cascade”
E = 375 TeV
~300
m @
E
= 1
PeV
"cascade"
Galactic center
IceCube: Aeff and resolution
1 year sensitivity E2·d/dE
diffuse point
8.110-9
[cm-2s-1sr-1GeV]5.510-9
[cm-2s-1GeV]
E< 1 PeV: focus on the Northern sky,
E > 1 PeV: sensitive aperture increases with energy full sky observations possible
IceTop Stations with DOMs – January 2004
digitized muon signals from DOMs
Am
plitu
de (A
TWD
cou
nts)
vs t
ime
(ns)
power cable
signal, freeze control,
temperature controlcables
27.1, 10:08: Reached maximum depth of 2517 m, reversed direction, started to ream up28.1, 7:00: drill head and return water pump are out of the hole, preparations for string installation start7:52: Handover of hole for deployment9:15: Started installation of the first DOM (DOM 60)12:06: 10th DOM installed22:36: 60th DOM installed Typical time for DOM installation:12 min22:48: Start drop29.1, 1:31: String secured at depth of 2450.80 m20:40: First communication to DOM
IceCube first string: january 2005
an IceCube-IceTop event
deployed string
AMANDA
4 IceTop stations
timing verification with flashers
Outlook.
as a framework: high energy neutrino astronomy
the world of neutrino telescopes: current projects
recent physics results from AMANDA and Baikal
ICECUBE: status and capabilities
summary
• a wealth of physics results from the currently working neutrino telescopes on several topics
• sensitivity reaching the level of current predictions of production in AGN. Some models already excluded @ 90%CL
• first Km3 project (IceCube) started at the South Pole: first events seen
• two projects + R&D efforts for a Km3 detector in the Mediterranean
summary
Absorption
dust
icebubbles
dust
optical properties:data from calibration light sources deployed along the strings and from cosmic ray muons.
absorption length
@ 400 nm
eff. Scattering length
@ 400 nm
110 m 20 m
effective scattering length absorption length
on average:
detector medium: nice icedetector medium: nice ice
AMANDA depthAMANDA depth
Preliminarysource
nr. of events(4 years)
expectedBG
(4 years)
time window
Markarian 421 6 5.58 40 days1ES 1959+650 5 3.71 40 days3EG J1227+4302 6 4.37 40 daysQSO 0235+164 6 5.04 40 daysCygnus X-3 6 5.04 20 daysGRS 1915+105 6 4.76 20 daysGRO J0422+32 5 5.12 20 days
search for excesses in time-sliding windows:galactic objects: 20 daysextra-galactic objects: 40 days
… out of 12 Sources → no statistically significant effect observed
timeevents
sliding window
search for neutrino flares without a-priori hypothesis on their time of occurrence
search for neutrino flaressearch for neutrino flares
AMANDA: sensitive in very different energy regimes
Energy range production site(s)Energy range production site(s)
MeV Supernovae
GeV-TeV Atmosphere
Dark matter from Sun/Earth Galactic center
TeV-EeV
QuasarsSN remnantAGNGRB
galactic
extragalactic
•Transient Waveform Recorder system installed between the 2001 and 2004 campaigns• Increased OM dynamic range x ~100
• Increased 1pe detection efficiency
• Virtually dead-time free
• Manageable trigger rate: ~150 Hz (majority 18)
• Possibility of using software trigger
• Under evaluation
Physics benefits:• Improved angular resolution• Improved energy resolution
UHE/EHE physics
TRANSIENT WAVEFORM RECODER UPGRADETRANSIENT WAVEFORM RECODER UPGRADE
Up to 18 holes per season:
Nov.: preparationDec.: constructionJan.: constructionFeb.: commissioning
Deploymentof string N
Drilling of hole N
0h 12h 24h 36h 48h 60h 72h 84h
Time
IceCube: time planIceCube: time plan
Diffuse sensitivity Point source sensitivity
IceCube: sensitivitiesIceCube: sensitivities
1 year sensitivity E2·d/dE
diffuse point
8.110-9
[cm-2s-1sr-1GeV]5.510-9
[cm-2s-1GeV]
IceCube+AMANDA eventIceCube+AMANDA event
• verification of newly deployed string
• off-line synchronization of AMANDA and IceCube data
May '02 July '02June '02
Error bars: off-source background per 40 days
sliding search
window
Preliminary
Example: 1ES1959+650“Orphan flare” (MJD 52429)
POINT SOURCE SEARCH: TIME WINDOW EXCESSPOINT SOURCE SEARCH: TIME WINDOW EXCESS
Preliminary!
... very rare - very high energy events
many proposals for radio and acoustic detectors in ice, water, salt, from moon ..
e.g. ice:>>km attenuation lengthsparse instrumentation100-fold volume increase
... or moon, ice radio emission
>100
< 10 GZK neutrinos/year
RICE AGASA
Amanda, Baikal2002
2007
AUGER Anita
Amanda,Antares, Baikal, Nestor
2012 km3
Auger+ new techn.
2004
RICE GLUE