Neutrino Astronomy at the South Poledesiati/talks/lathuile/talk.pdfDiv. of High Energy Physics,...
Transcript of Neutrino Astronomy at the South Poledesiati/talks/lathuile/talk.pdfDiv. of High Energy Physics,...
Neutrino Astronomy at the South PoleStatus of AMANDA Experiment
Paolo Desiati
University of Wisconsin- Madison
for the AMANDA Collaboration
La Thuile, Valle d’Aosta (Italy)
March 10, 2003
Neutrino Astronomy at the South Pole – p.1/30
AMANDA CollaborationBartol Research Institute, University of DelawareDept. of Physics, University of California BerkeleyDept. of Physics, University of California IrvineDept. of Physics, Pennsylvania State UniversityDept. of Physics, University of Wisconsin - MadisonDept. of Physics, University of Wisconsin - River FallsLawrence Berkeley Laboratory, BerkeleyDept. of Physics, University of Kansas - Lawrence
Dept. of Physics, University of Alabama - Tuskaloosa
Universidad Simón Bolvár, Caracas
ULB - IIHE, BusselsVUB Brussels
Université de Mons-Hainaut, MonsImperial College, LondonDESY-Zeuthen, ZeuthenMainz Universität, Mainz
Wuppertal Universität, WuppertalDept. of Physics Stockholm University, StockholmDiv. of High Energy Physics, University of Uppsala, Uppsala
Dept. of Technology, University of Kalmar, Kalmar
Neutrino Astronomy at the South Pole – p.2/30
AMANDA-II Experiment
� 19 strings
� 677 Optical Modules (OM)
� 200 meters diameter
� 500 meters tall
� completed in 1999
� 1997-99 AMANDA-B10� 10 strings, 300 OM
Neutrino Astronomy at the South Pole – p.3/30
AMANDA-II Deployment
� drill 2,000 m holes with�� � �
water
� hole diameters is
� � � �� but varies withdepth to correct for icetemperature profile
� drilling time is
�� � � �
� deploy strings withoptical sensors
� deployment time is �
� � �
Neutrino Astronomy at the South Pole – p.5/30
Why Neutrinos ?
Astronomical MessengersAstronomical MessengersNeutrinos
Photons
20 221816141210 11 13 19 2117
Log(E) (eV)
15
Protons
TeV
PeV
EeV
Sun
,S
N19
87A
Neutrino Astronomy at the South Pole – p.6/30
Detection Principle
�
Cherenkov photons are detectedby PMTs
�
tracks are reconstructed by
maximum likelihood method of
photon arrival times
�cascades have a sphericaltopology
�need specific reconstruction
technique
� � ice properties
� � array geometry
Neutrino Astronomy at the South Pole – p.7/30
Ice and Geometry
10-2
10-1
300 350 400 450 500 550 600
1/50
1/33
1/25
1/201/161/141/121/111/10
1/334
1/250
1/2001/1671/1431/1251/1111/100
κ = 1.07 ± 0.05MCdust = 6.95 ± 1.89
κ = 1.14 ± 0.02MCdust = 3.79 ± 0.45
wavelength [nm]
be(λ) = (λ/532) -0.84be(532)
abso
rptio
n co
effi
cien
t [m
-1]
EUVRMYAG1760 m1690 m
effective scattering coefficient [m-1]
(z-1730
m)
[m]
-350
-300
-250
-200
-150
-100
-50
0
50
100
150
200
250
0.01 0.02 0.03 0.04 0.05 0.06 0.07
�
ice optical properties nonhomogeneous�
scattering/absorption varies withdepth and
�
�
average properties at � �� ��� �
�� � � � absorption�� � � effective scattering
�in-situ calibration lasers usedalso for geometry/timecalibration�geometry precision is � ��� � �
�
photon arrival time precision ��� �
Neutrino Astronomy at the South Pole – p.8/30
Cosmic Ray Muons
Atmospheric Muons Angular Distribution
cosΘ
Φµ
(cm
-2se
c-1sr
-1)
10-9
10-8
10-7
0.2 0.25 0.3 0.35 0.4 0.45 0.5 0.55 0.6 0.65 0.7 0.75 0.8 0.85 0.9 0.95 1
� �! " � �� #%$ &
in average�
good quality tracks�
resolution
'( )� � � *
� �� � +
ice models uncertainty
�
Data/MC normalized tovertical bin�MC uses CORSIKA withWiebel-Sooth primary CR
�
curves from Klimushin et al.Phys.Rev.D, 64, 014016�
predictions with experimen-tally measured parameters
Neutrino Astronomy at the South Pole – p.9/30
Muon/Primary Energy Spectrum
�
CORSIKA with Wiebel-Sooth CRspectrum�, - . . )� � /0 1 ��� �2
from MC�
primary cosmic ray spectrum�, 354 )� � 6� 1 � � � �
�
use of regularized unfolding�
sea-level single muon spectrum�, 3 4 )� � 6� 1 � � � 6
Neutrino Astronomy at the South Pole – p.10/30
CR Composition
Etrue = 1 PeV - 10 PeVEntries 1798Constant 3057.Mean -0.3207E-01Sigma 0.6900E-01
log(Ereco)-log(Etrue)
0
500
1000
1500
2000
2500
3000
3500
-0.6 -0.4 -0.2 0 0.2 0.4 0.6
even
ts
�
SPASE-AMANDA coincidence
�
SPASE S30 ( 798 :2 � � ; )�
AMANDA K50( < => ?@ : � � � ; )
�strong correlations with
=
and�BAC�
SPASE/AMANDA resultnormalized at first point
� � 6 +
resolution in
�BA C in 1-10PeV
Neutrino Astronomy at the South Pole – p.11/30
Neutrino Analysesup/down energy source arrival count topology
direction time rate
Atm D�E F
Diff & EHE D F F
Point Sources:
F F FAGN,WIMPS
GRB
F F F F
Cascades
F F F F
Supernovæ
F
L1 [OM cleaning, first guess fit, loose angular cut]
L2 [max likelihood fit, bayes fit, tighter anguar cut, direct hits]Neutrino Astronomy at the South Pole – p.12/30
Atmospheric G in AMANDA-B10
cosθ
Data
Atmospheric ν MC
0
5
10
15
20
25
30
35
40
-1 -0.9 -0.8 -0.7 -0.6 -0.5 -0.4 -0.3 -0.2 -0.1 0
dN/dcosθ
� in 130.1 days lifetime
�
MC normalized to data at high cut level
� H$I J K LM Nevents
� H �O K L PQ RS
events
� Background contamination
� T UWV X M Y
� pointing resolution
S[Z L �
� \ \ ]!^ _ ` a D ` S[Z N bc^ _
�
Physical Review D, 66, 012005 (2002)�
Nature, Vol 410, 22 Mar 2001, 441-443
Neutrino Astronomy at the South Pole – p.13/30
Atmospheric G in AMANDA-II
0102030405060708090
100
-1 -0.8 -0.6 -0.4 -0.2 00
102030405060708090
100
-1 -0.8 -0.6 -0.4 -0.2 0
0102030405060708090
100
-1 -0.8 -0.6 -0.4 -0.2 0
cosθ cosθ
cosθ cosθ
0102030405060708090
100
-1 -0.8 -0.6 -0.4 -0.2 0
Exp Data 1226 Exp Data 933
Exp Data 709
MC Data 737 MC Data 674
MC Data 610 MC Data 519Exp Data 527
� pure d sample
� easier to obtain than B10
� only 3 cuts e d fg
� 197 days in 2000
� goodunderstanding ofatmospheric dih� j " 3 < � �
� kcl 3 @ � � � *
�
high fit quality�
uniform lightdeposition along thetrack�
effect of cuttightening
Neutrino Astronomy at the South Pole – p.14/30
Diffuse Gnm in AMANDA-B10
log10(Eν) [GeV]
even
ts
10-5 E-2 νµatmos. νµ
pass initial cuts
passallcuts
10-1
1
10
2 3 4 5 6 7
log10(Eν) [GeV]
log 10
E2 Φ
ν(E
) [c
m2 s
-1 s
r-1 G
eV]
Atmosphericneutrinos
SS QC pred.A-B10 lim.
Charm DA-B10 lim.
Charm Dpred.
MACRO E-2 νµ
Baikal E-2 νe
Frejus νµ (diff. at Eν=2.6 TeV)
AMANDA-B10 E-2 νµ
AMANDA-B10 E-2 νe
-7
-6.8
-6.6
-6.4
-6.2
-6
-5.8
-5.6
-5.4
-5.2
-5
3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8
�
search for HE D E from unresolved sources�
assumes harder spectrum�o prq )� s� �t uwv �t x O �t x �t y �z t y
�
background (atm D E ) suppressed by energy cuts(nch)�
90% of events in/ {$ & < � p <� |}$ &
�
limit(no sys uncertainty)�o ~� � < 6� 6 s� �t � s �t x O �t x �t y �z t y #%$ &
�limit(with 25% sys uncertainty)�o ~� � < 0 � � s� �t � s �t x O �t x �t y �z t y #%$ &
�submitted to Physical Review Letters
Neutrino Astronomy at the South Pole – p.15/30
Diffuse Gm in AMANDA-II
�o pq )� s� �t �v �t x O �t x �t y �z t y
�
90% of events in� � {$ & < � p <� � |}$ &
�
90% CL Feldman-Cousins average upperlimit�
optimal energy cut at nch=93�
sensitivity for 1y� � 6 s� � t �v �t x O �t x �t y �z t y
� s 4.5 better than AMANDA-B10�
still on-going analysis
Neutrino Astronomy at the South Pole – p.16/30
Point Sources in AMANDA-B10
�
Ap J, 583, 1040 (2003)
84
9 1 3 2
6
57
10
1 - Mkn5012 - Mkn4213 - NGC41514 - 1ES23445 - 3C66A
6 - 1ES1959+650 7 - Crab Nebula 8 - Cassiopeia A 9 - Cygnus X-310 - Geminga
-1.5
-1
-0.5
0
0.5
1
1.5
-3 -2 -1 0 1 2 3
�median pointing resolution� )2 � � *
�northen hemisphere sky dividedin 154 bins ( �� � * s� � *
)
�
looser cuts than atmospheric D �
higher sensitivity� H$ I J K � X U
events
Neutrino Astronomy at the South Pole – p.17/30
Point Sources in AMANDA-II�
cut optimization at eachdeclination band (
� �� � 2 *
)�
good sensitivity close to horizon�
10% BG contamination in
� @ � *
� j8�� ) / � 6
events in
� @ � *
�
northen emisphere divided in 300bins ( � 6 * s 6 *
)�
no significant excess observed
24h 0h
°-90
°90 1555 events
θ90 100 110 120 130 140 150 160 170
even
tN
20
40
60
80
100
120
Data
MCνAtm
Neutrino Astronomy at the South Pole – p.18/30
Point Sources in AMANDA-II
10-4
10-3
10-2
10-1
11010 2
0 1 2 3 4 5 6
10-3
10-2
10-1
1
10
10 2
0 1 2 3 4 5 6
10-4
10-3
10-2
10-1
11010 2
0 1 2 3 4 5 6
10-3
10-2
10-1
1
10
10 2
0 1 2 3 4 5 6
Significance Distributions
ξ
n. o
f bin
s (δ1
0O)
ξn.
of b
ins (
δ10O
)
ξ
n. o
f bin
s (δ1
0O)
ξ
n. o
f bin
s (δ1
0O)
ξ
n. o
f bin
s (δ1
0O)
10-4
10-3
10-2
10-1
1
10
10 2
0 1 2 3 4 5 6
Significancedistribution inall-sky gridsearch
Neutrino Astronomy at the South Pole – p.19/30
Point Sources in AMANDA-II
Source
�
1997 2000
Crab
L L �
4.2 2.1
Mkn 421
S �Z L �
11.2 3.1
Mkn 501
S QZ � �9.5 1.6
Cygnus X-3N XZ U �
4.9 3.1
Cass. AU �Z � �
9.8 1.0
Table 1: Sensitivities in
�� � ��� � � ���� � � �
Neutrino Astronomy at the South Pole – p.20/30
WIMPS from the center of Earth
� � vertical up-going muons�
high reco quality tracks�
8-dim cut to separate signal/bg�
simulation of�9� )� � ��� � � � � #%$ &
�6 annihilation channels
��9� �2 � +
��� � � ��� 2 +
�
no excess observed
�
Physical Review D, 66, 032006(2002)
Neutrino Astronomy at the South Pole – p.21/30
Gm from GRB
GRB trigger timet=0
10 sec−1 hour +1 hour
BG from off−time BG from off−time
(T90)�
AMANDA-B10�
273 BATSE triggers in 97-99�
binsearch
� � 6� � � *
�
high quality track fit
�
AMANDA-II�
44 BATSE triggers in 2000�
binsearch
� <� � *
�
high quality track fit�
smooth hits distribution along track
� no excess found in anyanalyzed year
Neutrino Astronomy at the South Pole – p.22/30
Cascades in AMANDA-B10
log10(Eν/GeV)
E2 Φ
[
GeV
s-1
sr-1
cm
-2 ]
AMANDA-II νe
PRELIMINARY
νe νµ
AMANDA-B10 νµ
AMANDA-B10 νe
BAIKAL νe
10-7
10-6
3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8
� ���� : D8 ; <
/� � s� � t � s �t x #%$ & O �t x �t y �z t y
� � {$ & < � p <2 � � {$ &
�
cascades from em/hadronicshowers� D8 , D� CC+NC� D¡E NC
�
vertex position� '¢z � �� � �
�energy resolution� '£}¤ ¥ : �§¦ -� ¦ ; � ��� � � � � ��
better resolution than mutracks
�
performance tested with in-situlight sources
�
Physical Review D, 67, 012003(2003)
Neutrino Astronomy at the South Pole – p.23/30
Cascades in AMANDA-II
10-2
10-1
1
10
10 2
4 4.5 5 5.5 6 6.5log10(Ereco/GeV)
even
ts /
197
d / 0
.2
experiment
background MC
E-2 signal MC
preliminary (2000 data) �
specific filter applied�
spherical topology�
energy cut� �}¨ search
�o p5© )� s� � t �wv �t x O �t x �t y �z t y
� � ��� : D8 ; < ��� / s� �t � s
�t x #%$ & O �t x �t y �z t y
� 2 {$ & < � p <� � |}$ &
Neutrino Astronomy at the South Pole – p.24/30
UHE Gm in AMANDA-B10
log10(Eν) (GeV)
E2 dN
/dE
ν (G
eV c
m-2
s-1sr
-1)
10-7
10-6
10-5
4 5 6 7 8 9 10
Flys Eye
ν
AMANDA
Baikal νe
AMANDA−B10 UHE
µν
νAMANDA
MACRO
e
µ
� D¡E with
� @ � � y u $ &from diffuse
sources�
concentrated in the horizon�selection of very bright events
�systematics study accounts for�
ice properties modeling�
absolute detector sensitivity�
neutrino cross sections
�
analysis under way in AMANDA-IIalso
Neutrino Astronomy at the South Pole – p.25/30
G from Supernovæ
�
Astrop Phys, 16 (2002)‘, 345-359
�
counting rate excess (in 10s bin) fromD8 ª J «� ª $
�
noise from OM only (300/1100 Hz)�
subsample of OM over 97/98 isselected�
get stable counting rate with a movingaverage
�AMANDA-B10�
70% coverage of Galaxy�o ¬� ) �� 2 ev/y (90% CL)
�
AMANDA-II�
90% coverage of Galaxy
Neutrino Astronomy at the South Pole – p.26/30
Summary
� AMANDA-B10 data published
� AMANDA-II data under analysis
� from 2002 online-filter
� AMANDA-II higher sensitivity
� THE FUTURE: IceCube
� in 2004 start to build
� 4800 OM (60 / string)
� string spacing 125 m
� digital transmission
� 1 km
2
instrumented volume
� IceTop surface arrayNeutrino Astronomy at the South Pole – p.27/30