IceCube Review
Our present status

Shigeru Yoshida
Department of Physics
Chiba University2007-2008:
18 Strings

2006-2007:
13 Strings

2008・2009 Data
40 strings
80 IceTop tank

IceCube2009-2010
59 strings
2010-2011
79 strings

2005-2006: 8 Strings

1450m

2004-2005 : 1 String
80+6 Strings
60 Optical Modules
17 m between Modules
125 m between Strings
2450m

The IceCube Collaboration
Germany:

Sweden:USA:
Bartol Research Institute, Delaware
University of California, Berkeley
University of California, Irvine
Pennsylvania State University
Clark-Atlanta University
Ohio State University
Georgia Tech
University of Maryland
University of Alabama, Tuscaloosa
University of Wisconsin-Madison
University of Wisconsin-River Falls
Lawrence Berkeley National Lab.
University of Kansas
Southern University and A&M
College, Baton Rouge
University of Alaska, Anchorage

Uppsala Universitet
Stockholm Universitet

UK:
Oxford University

Switzerland:
EPFL

DESY-Zeuthen
Universität Mainz
Universität Dortmund
Universität Wuppertal
Humboldt Universität
MPI Heidelberg
RWTH Aachen
Ruhr-Universität Bochum

Belgium:
Université Libre de Bruxelles
Vrije Universiteit Brussel
Universiteit Gent
Université de Mons-HainautJapan:
Chiba University

New Zealand:
University of Canterbury

33 institutions, ~250 members
http://icecube.wisc.edu

DOM
Digital Optical ModuleHV Base
“Flasher Board”

Main Board(DOM-MB)10” PMT13” Glass(hemi)sphereIceCube Event Topology
Main channels

sub-channels“Composite Bright Track”“Track”

pe+e-e+e- photo-nuclear
g pair-creation
bremsstrahlung“Cascade”

Data Filtering at South PolePY 2008 season
40 strings ~ a half of the completed IceCube

Simple Majority Trigger
8 folds with 5 m sec

Muon Filter

EHE Filter

selects“up-going” tracks

selects“bright” events~20 Hz~1.3 Hz~ 950 Hz

Cascade Filter

Many others“cascade”-like events Min Bias
Moon
IceTop~17 HzetcNPE > 630 p.e.

To Northern Hemisphereselects

Point Source SearchMaterials to cooknm  m basem filtered, EHE filtered and min-bias events

Require Quality cuts in multiple stages

Common aspects
In many other analysis

Point source specificto filter out vastly dominateddown-going muons

to realize reasonable agreement
between MC and data
to create a sample of eventswith good angular resolution

Point Source Search
Event Selection
Cut #1q > 90 deg (“up-going” cut)Attention: still atm m dominates!!
Needs a series of further filteringto get us to n level

Cut #2
Paraboloid sigma cut

sparaboloid < 3 deg

Ensure good angular resolution

Point Source Search
Event Selection
Cut #3keep

cuts with m track likelihood

cut

Cut #4split zeniths > 80 deg

Cut #5
Bayesian likelihood ratio
Test of down-going hypothesis

Now on n level

Cut #6
cuts on track length and Nch

cutkeep

Zenith Angle Distribution
in the final sample* Introduced hard “down-going” cuts for extension to Northern sky(retains only O(PeV) down-going events)
Jon Dumm (UW-Madison)n skymapup-going m’s w/ atmospheric n BG

down-going PeV m’s w/ cosmic-rays BG

All sky search: post-trial p-value 18%
Hottest spot: RA 113.75 Dec 15.15 -log(p)=5.28
Jon Dumm (UW-Madison)

Source List Results
p-value

Crab--BL Lac
0.226
Mrk 501
0.421
Mrk 421
0.142
M87--CygA
0.439
PKS 1622-297 0.048

IceCube Preliminary

The highest significancefrom list of the 39 IceCube sources

Pretrial 4.8 % post-trial 62 % for the source list

* Shown here is only a part of the IceCube pre-determined source listJon Dumm (UW-Madison)

Point Source Sensitivity
IceCube Preliminary

Jon Dumm (UW-Madison)

UHECR correlation analysis
IceCube 2008 point-source skymap
36900 events

27 events from PAO in the 2007 publication. Energy > 57 EeV
42 events released from PAO 2010. Energy > 57 EeV
13 stereo events from HiRes. Energy > 56 EeVRobert Lauer (DESY)UHECR correlation analysis
Correlation search optimized for
hypotheses of magnetic deflection of cosmic rays by 3 degree
J. Abraham et al (Pierre Auger collaboration) Astropart. Phys. 29 188-204 (2008).

Unbinned Likelihood search with s = 3 degree

IceCube Preliminary-2(log L(signal) – log L(bg)) = 0 i.e., consistent with the background-only hypotheses

Binned search with 3 degree radius
298 IceCube events found in 82 bins of 3 deg radius

274 events expected from the background-only hypothesis

1.48 s (p-value 0.069)
Note: n emission is assumed here from O(TeV) extending to O(EeV)(typically with E-2)
i.e., not like the GZK n emission where main energy range is above PeVRobert Lauer (DESY)GRB model-dependent SearchMaterials to cook
m filtered and EHE filterednm  m baseRequire Quality cuts in multiple stages

Common aspects
In many other analysis

GRB specificto filter out vastly dominateddown-going muonsZenith > 85 deg.

to realize reasonable agreement
between MC and data
use “off-time” data as the BG sample
to train the BDT

Building of the PDFs
Unbinned Maximum Likelihood
PDF

Total PDF.
Time PDF

Predicted n spectra
Guetta et al Astropart.Phys. 20 (2004) 429

Optimize BTD score
to maximize the discovery
potentialNo association of n’swith GRB..
109 GRBs detected by Fermi, Swift, Konus, and WAM
in the IceCube FOV (2009 June – 2010 May)

Peter Redl (UMD)

We are on the way to indicate GRBs areunlikely to be a major UHECR origin.

Astronomical Diffuse Neutrinos
Neutrino can travel very long, carrying the fossil record ofthe Universe's emission activities.

gnDiffuse n SearchO(100 TeV) ~ 10 PeV

Materials to cook
m filtered, EHE filtered eventsnm  m baseRequire Quality cuts in multiple stages

Common aspects
In many other analysis

to filter out vastly dominateddown-going muons

to realize reasonable agreement
between MC and data

Diffuse analysis specificStronger cuts (than PS search) required forenhancing purity of n sample

Diffuse n search
Quality cuts : stronger than those for the point-source search
Level 1q > 90 deg

Level 2

cuts with m track likelihood

Level 3sparaboloid < 3 deg

Level 4

Bayesian likelihood ratio
Level 5

Split Bayesian likelihood ratio

cutkeep

Test of down-going coincidence
m hypothesis Get into almost n level
Level 6

split zeniths > 80 deg
Level 7

cuts on track length and Nch
Sean Grullon (UW-Madison)

Now look at “energy” distribution
Calculates m’s energy loss (dE/dX) from the Cherenkov g profile

Sean Grullon (UW-Madison)

Final “Energy” distribution

O(100GeV~TeV)

Sean Grullon (UW-Madison)O(10TeV~100TeV)

Diffuse n limit
Now below the Waxman-Bahcall limit
IceCube Preliminary

nm only

This work

Sean Grullon (UW-Madison)

Atmospheric n spectrum
The quality cuts by the similar philosophy
but with the BDT training method
An independent analysis with slightly different event selections

IceCube Preliminary

dE/dX  EnSpectrum Unfolding
by SVD method
NIM A 372 (1996) 469

Warren Whuelsnitz (UMD)

No indication of prompt n and new physics (e.g. quantum gravity)

GZK n SearchO(PeV) ~ 10 EeV

Materials to cook
EHE filtered events

All n flavor baseNo strong quality cuts necessary because..

Unique featuresin this particular analysis

these n’s are more energetic thanatmospheric m BG
Just increase energy thresholdin analysis leads to better S/NGZK analysis specific issues• Earth filters out signal n as wellNorthcMSSM Neutralino Dark
Matterncc  bb ,t t  ,W W  ,... n s

Spin Dependent cross-section: Abundant hydrogen in Sun suitable
for spin dependent cross-section measures
Spin Independent cross-section: Many direct dark matter searches sensitivemCR

Dark matter searches:
Solar WIMPscc  bb (soft ),W W  (hard ),... n s
• Determine the muon
flux from the direction ofthe Sun••A few to 103 events per year
GeV to TeV energies• Limit the neutrinoinduced muons fromWIMP annihilation• A strong limit on SD
cross-section and goodpotential

Phys. Rev. Lett. 102 201302 arXiv:0902.2460
IceCube Preliminary

Dark Matter from theGalactic HaloDark matter density profiledn  s Au 
Rsc r dNn
J ( )dE
2
4p m dE2
sc2
c

Dark matter model

Measure or limit

PRELIMINARY

Dark Matter from the Galactic Halommtt

(My) Outlook• Point Source 感度は既に 1/√T 領域に入った。
GRB もかなり制限がついたが、あと3年程度はtransient 現象では何か起こっても不思議でない。
• Diffuse ν (GZK 含む)探索はまだ 1/T で感度がどんどん向上。Stay tuned!
new 2009-2010 data + published 2008-2009 data ２倍の向上
2012 年5月までの data combined  published results の５倍以上(full IceCube 3 years equivalent)• Deep Core physics 未開拓 特に100 GeV - TeVν astronomy