Recent Results
Lutz Köpke
University of Mainz, Germany
July 31, 2003
http://amanda.uci.edu

UpIce gra
Cu debe andNeutr

inosCosmicrays

Contributed papers to ICRC
Response of AMANDA to cosmic ray muonsCosmic ray flux measurement
Cosmic ray composition at the knee with SPASE and AMANDA
Atmospheric neutrino and muon spectra
Search for diffuse fluxes of extraterrestrial muon neutrinos
AMANDA-B10 limit on UHE-Neutrinos
Search for high energy neutrinos of all flavours
Search for extraterrestrial point sources of neutrinos
Search for muons from WIMP annihilation in center of earth
Search for high energy neutrinos from GRBs
Online search for neutrino bursts from Supernovae

New capabilities of the AMANDA detector
The IceCube high energy neutrino telescope
IceTop: the surface component of IceCube
Simulation of ice Cherenkov detectors for IceTop+ 3 individual contributions
black: parallel talkPhysics motivation
origin and acceleration of cosmic rays
understand cosmic cataclysms
find new kind of objects?
neutrino properties (ντ , cross sections ..)dark matter (neutralino annihilation)•••

tests of relativitiy ....
search for big bang relics ...
effects of extra dimension etc. ...

Neutrino source candidates
Supernova remnant

Microquasar(SS433 etc.)≈ 1 LJ

Active Galaxy(optically dense, e.g. FRII)≈ 106 LJ

Crab nebulaBlack hole with≈ mass of sun
galactic

Black hole with
108 x mass of sun
extra-galacticDetection of νe ,νµ , ντνe:νµ:ντ =1:2:0 at sourceoscillation→O(km) long muon tracks

Electromagnetic and hadronic cascades≈ 15 mdirection determination
by Cherenkov light timingνe:νµ:ντ =1:1:1 at Earth !

~5m

Detection of muon neutrinos
νµ (νe)cosmicradiation

Above O(PeV): significant ν absorption:

O(10 PeV)

νµ (νe)atmospheric muons

Earth acts as shield

O(PeV): use horizontal events
O(10 PeV): use events from above

Complementarity (point sources):E ≈< 100 TeV
Mediterranean (ocean)
Antares, Nestor, 1 km3 ...

South Pole (ice)
AMANDA, ICECUBE

galactic center in middle

dots: distribution of gamma ray bursts (GRBs)

Northern hemisphere detectors
Baikal NT200

1100 m deep
data taking since 1998new: 3 distant strings

AntaresMarch 17, 2003
2 strings connected
2400 m deep
completion: start 2006

NestorMarch 29, 2003
1 of 12 floors deployed
4000 m deep
completion: 2006

AMANDA II Detector
Amundsen-Scott Station South Pole

Opticalmodule (677)1996-2000

The AMANDA Collaboration
Antarctica
New ZealandVenezuela (1)JapanEurope (10+1)

USA (7+3)≈ 150 members
Bartol Research Institute
UC Berkeley
UC Iivine
Pennsylvania StateUW Madison
UW River Falls
LBL Berkeley
U. Simón Bolivar, Caracas
VUB, Brussel
ULB-IHEE, Bruxelles
U. de Mons-Hainaut
Imperial College, London
DESY, Zeuthen
Mainz Universität
Wuppertal Universität
Stockholm Universitet
Uppsala Universitet
Kalmar Universitet
South Pole Station Antarctica+ associated institutes
e.g. Chiba UniversityThe laboratory
South Pole
AMANDAThe new station
operating at least
until 2035

The Dome

Two events ...
Color displays: LE
Primary Channels
2370
13
232501
2631
402762383428933023
28213154
3285
193415
11
93546
3677
63807
93938
44069
54199 24330 2
Size displays: ADC

Size scaling: Lin<4<9<13<17<22<26<31<3<40<44<49<53<58<62<67<7

No external geometry file is opened.
Detector: amanda-b-10, 19 strings, 680 modules
Data file: he_deff.f2k
Displaying data event 1425281 from run 336
Recorded yr/dy: 2000/170
59857.5405130 seconds past midnight.
Before cuts: 264 hits, 264 OMs
After cuts : 264 hits, 264 OMs

200 TeV νe candidate

Detector capabilities
muons:
directional error:
2.0 - 2.5°energy resolution:¶ 0.3 – 0.4
coverage:2πνµ effective area(schematic):
ν-interaction inearth, cuts
2 -5m2

primary cosmic rays: (+ SPASE)
energy resolution:¶ 0.07 – 0.10
„cascades“: (e±, τ± , neutral current)
zenith error:
30 - 40°
energy resolution:¶ 0.1 – 0.2
coverage:
4π¶σ[log (E/TeV)]
10∝ Eν 2
3 cm2100 GeV

100 TeV

100 PeVposter 1-P-265

Atmospheric muons in AMANDA-II
Atmospheric muons and neutrinos: AMANDA‘s test beams
much improved simulation...but data 30% higher than MC ...
´ normalize to most vertical bin
Systematic errors:
10% scattering ( 20m @ 400nm)
absorption (110m @ 400nm)
20% optical module sensitivity
10% refreezing of ice in holePRELIM

INA

RY

threshold energy ~ 40 GeV (zenith averaged)

talk HE2.1-13

Cosmic Ray flux measurement
In some cases ice and OM-sensitivity effect can be circumvented ...
Φ(E)=Φ0E-γ

empirical separation of ice and OM
sensitivity effects

for QGSJET generator:γ (H) = 2.70 ± 0.02
Φ0 (H) = 0.106(7) m-2s-1sr-1TeV-1ILEPRM

YRA
IN

Spectral index γ compatible with direct
measurements, error competivie

talk HE 1.1-25

cosmic ray composition studies
AMANDA (correlate to #muons)

SPASE-2 (electronic component) - AMANDA B10 (muonic component)- unique combination!

AMANDA II

ironprotonlog()
VGe/ESPASE-2 (correlated to #electrons)

robust evidence for composition change around knee ...

talk HE 1.1-25

Composition change around „knee“1015 eVblue band: detector and model
uncertainties
red band: uncertainty due to low
energy normalization

confirms trend seen byother experiments ...
publication in preparation(1998 data)

1016 eV
A=30

A=6

talk HE 2.3-6

Atmospheric ν's in AMANDA-II
neural network energy reconstruction
regularized unfoldingPRELIMINARY

measured atmospheric neutrino spectrum
spectrum up to 100 TeV
compatible with Frejus data
1 sigma energy error
presently no sensitivity to LSND/Nunokawa
prediction of dip structures between 0.4-3 TeV

In future, spectrum will be used
to study excess due to cosmic ν‘sposter HEtalk HE 2.3-4

Excess of cosmic neutrinos? Not yet ...
.. for now use number of optical modules hit as energy variable ...

cascades (2000 data)preliminary (2000 data)

events / 197 d / 0.2muon neutrinos (1997 B10-data)
accepted by PRL

102experiment

background MC-2E signal MC (νe)

10

„AGN“ with 10-5 E-2
GeV-1 cm-2 s-1 sr-1

1-1

10

4

4.5

5

cuts determined by MC – blind analyses !

5.5
6
6.5
log10(Ereco/GeV)poster 1-P-256

poster 1-P-257

Diffuse flux muon neutrinos
Note that limits depend on assumed energy spectrum ...

3·103 – 106 GeV:E2 Φ(E) < 8 ⋅10-7
GeV-1 cm-2 s-1 sr-1
2.5 ·106 – 5.6 ·108 GeV:E2 Φ(E) < 7.2 ⋅10-7

prel.

GeV-1 cm-2 s-1 sr-1

Expected sensitivity 2000 data:~ 3 ⋅10-7 GeV-1 cm-2 s-1 sr-1

AMANDA II (with 3 years data):~ 10 X higher Sensitivity

Diffuse limit cascades
80 TeV – 7 PeV

talk HE 2.3-4

after acceptance expect:νe : νµ : ντ ≈ 1 : 0.67 : 0.85 events
2 candidate events total observed

effective volumePRELIM

INA

RY

90% CL upper limit:
E2Φall ν (E) < 9·10 - 7 GeV cm-2s-1sr-1

talk HE 2.3-4

Flux results summary (all flavors)
assuming νe:νµ:ντ =1:1:1 ratio:
special analysis for resonantν e + e − →W − →ν e + e −production (6.3 PeV)
multiplicative factor 3 applied
for single νe ,νµ channels …
...can combine analyses !

2000 νµ analysis will yield comparable result

talk HE 2.3-5

Point source search in AMANDA IISearch for excess events in sky bins for up-going tracks
697 events observed above horizon
3% non-neutrino background for θ > 5°
cuts optimized in each declination bandPRELIMINAabove horizon: mostly atmospheric ν‘sbelow horizon:mostly fake eventssky subdivided into 300 bins (~7°x7°)

no clustering observed - no evidence for extraterrestrial neutrinos ...

RYtalk HE 2.3-5

Selected point source flux limits
PREsensitivity ≈ flat above horizon - 4 times better than B10 ¶!
Sources declination

declination averaged sensitivity:Φνlim ≈ 2.3•10-8 cm-2s-1 @90%

LIM

INA

RY

1997 ¶2000

o-0.7

SS433

5.0

M87

12.4

o

17.0

1.0

Crab

22.0

o

4.2

2.4

Mkn 421

38.2

o11.2

3.5

Mkn 501

39.8

o

9.5

1.8

Cyg. X-3

41.0

o4.93.5Cas. A

58.8o9.8

1.2

upper limits @ 90% CL in units of 10-8cm-2s-1¶ published Ap. J, 582 (2003)

Nmuons/cm2 s1

Expected source
sensitivity
AMANDA137 days

10-14

MACRO
8 years

SCrabpublished data

Mark. 501

10-15
SS-433

Antares(2007+)

preliminary 2000 data

GX
339-4

10-16

AMANDA+16 (2007)

1 km3

10-17-90-45

0

1 km3 detectors, 3 years
45declination (degrees)90

talk OG 2.4-7

GRB ν search in AMANDA
Search for νµ candiates correlated with GRBs - background established from data

PRELIMINARY∆Ψ<20°10 min

Year #GRB
199778
1998
99
1999
96
2000
44
Total 317

bkg
0.10
0.20
0.20
0.60
1,30

observed
00000317 BATSE triggers (1997—2000)
effective µ-area ≈ 50000 m2
low background due to space- time coincidence

No excess observed!
assuming WB spectrum 4 x 10-8GeV/s/cm2/sranalysis continues with non-triggered BATSE and IPN3 data …

Outlook... did not mention new improved search for WIMPs (HE 3.3-6)... supernova detection (1-P-258) etc.
..no extraterrestrial neutrinos found yet ...but:
combined analysis 1997-2003: 8 x more days !
improved selection and analysis methods ...
new transition waveform based readout installed 02/03
improved performance in particular at high energies (1-P-264)
first IceCube strings 2004/05 – combined analysis with AMANDA

Importance of all flavor detection
Extended source with νe:νµ:ντ =1:2:0 production (e.g. π± decay) :E.g.: Maki-Nakagawa-Sakato mixing matrix with θ12=30°, θ23=45°, θ13=0°: 62 0
1 NMS3 2U=× −18 
132−νe:νµ:ντ =1:1:1 on earth

O(10) x less background for νe – but you don’t profit from long µ-range
Regeneration of ντ - no absorption in earth even at very high energies !

Theoretical bounds and future
DUMAND test string
FREJUS

MACRO

opaque for neutronsatmo

NT-200AMANDA-97

spheAMANDA-00

ric ν µAMANDA-II

MPR
MPR

neutrons can escapeÅNT-200+

W&B
W&B

IceCubeMannheim, Protheroe and Rachen (2000) – Waxman, Bahcall (1999)´ derived from known limits on extragalactic protons + γ-ray flux