South Pole
Download
1 / 17

Cosmic rays at the knee and above with IceTop and IceCube - PowerPoint PPT Presentation


  • 71 Views
  • Uploaded on

South Pole 4 Feb 2009. Cosmic rays at the knee and above with IceTop and IceCube. Serap Tilav for The IceCube Collaboration. IceCube Neutrino Observatory Neutrino Telescope & 3D Cosmic Ray Detector. Air shower detection @ 2835m altitude (680 g/cm 2). IceTop. IceTop

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' Cosmic rays at the knee and above with IceTop and IceCube ' - magee-berger


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Cosmic rays at the knee and above with icetop and icecube

South Pole

4 Feb 2009

Cosmic rays

at

the knee and above

with

IceTop and IceCube

Serap Tilav

for

The IceCube Collaboration


Cosmic rays at the knee and above with icetop and icecube

IceCube Neutrino Observatory Neutrino Telescope & 3D Cosmic Ray Detector

Air shower detection @ 2835m altitude (680 g/cm2)

IceTop

  • IceTop

    • EM component near shower max

    • shower size & arrival times over 1km2

  • IceCube

  • Muonic component @ 1450m-2450m depth in ice

  • muon bundle energy over 1km

IceCube


Cosmic rays at the knee and above with icetop and icecube

IceTop/IceCube

Motivation for Air Shower Measurements

in Energy Range 3.1014 eV – 1.1018 eV

spectrum & composition

around the knee

iron bump ?

2nd knee ?

transition from

galactic to extra-galactic

from Andreas Haungs, Kascade


Icetop tank
IceTop Tank

Solid block of clear ice

“ Ice Cherenkov Tank”

Single tank detects secondary

particles in air showers :

-- MeV e±

-- converting γ

-- ~1 GeV μ

Light yield (Cherenkov and stochastic) for each particle type is derived from a detailed GEANT4 simulation and parameterized


Tank response to vem and calibration with muon telescope

All events

Vertical muons

(tagged with muon telescope)

Tank response to VEM and calibration with Muon telescope

Full Spectrum

Muon Peak

all particle

spectrum

of the DOM

Vertical

Muon Peak

signals in coincidence

with muon telescope

L. Demirors et al.,

ICRC07

arXiv:0711.0353


Icetop station
IceTop Station

Photo: James Roth, Dec 8, 2007

  • 2 tanks per station

    • 1 tank hit  muon, e or γ

    • both tanks hit  air shower

  • 2 DOMs per tank

    • 1 HG, 1 LG for dynamic range


Cosmic rays at the knee and above with icetop and icecube

2005 4 stations

2006 12 stations

IceTop-26

2007 10 stations

IceTop-40

2008 14 stations

IceTop-59

2009 19 stations

IceTop Deployment 2005-2009

IceTop-26

First attempt on Energy Spectrum

IceTop-40

First attempt on Composition

14 stations in 2010

7 stations in 2011


Cosmic rays at the knee and above with icetop and icecube

IceTop-26 Reconstruction

Lateral shower profile at 125m

S125 : signal at r = 125m

β: slope at r = 125m

κ = 0.303 fixed

S. Klepser et al.,

ICRC07

arXiv:0711.0353

  • Fluctuations extracted from data

  • Likelihood function from data & simulation

    -- untriggered stations are also accounted for

  • Direction reconstruction: curved shower front


Cosmic rays at the knee and above with icetop and icecube

IceTop-26 Resolution & Efficiency

Simulations: CORSIKA with Sibyll and Fluka

for3 zenith bins [0-30]°,[30-40]°,[40,46]°

S125

Eprimary derived from proton simulations

for zenith range [0-30]°

Direction ~1.5°

Core ~9 m

Energy ~ 16%

Effective area ~ 0.094 km2

full efficiency reached > 1 PeV

  • requires ≥ 5 station triggers

  • containment criteria

  • quality cuts


Cosmic rays at the knee and above with icetop and icecube

IceTop-26 Detector Response

Detector response is characterized

as

Response Matrix(RM)

Proton

Iron

Resolution

Efficiency

….

Primary particle

Primary Energy

Zenith Angle

+

RM


Cosmic rays at the knee and above with icetop and icecube

Unfolded Spectrum

Composition sensitive zenith behavior

IceTop-26 Energy Spectrum

Raw Energy Spectrum

Proton only

Response

Matrix

Iron only

5 months of data 1 Jun – 31 Oct 2007

1.1 107 events processed

4.106 events passed

F. Kislat et al.,

ICRC09


Cosmic rays at the knee and above with icetop and icecube

IceTop-40/IceCube

Coincident Events

Data collected at 2 Hz rate

Method

  • Reconstruct shower direction and core location with IceTop

  • fix core, improve direction using IceCube reconstruction, improve core using the improved direction --- 2 iterations

  • Reconstruct muon bundle energy loss using charge flow information at each layer in IceCube

  • Muon bundle energy loss is composition sensitive


Cosmic rays at the knee and above with icetop and icecube

IceTop-40/IceCube

Direction Resolution

Core resolution ~ 12-14 m

Angular resolution < 1°


Cosmic rays at the knee and above with icetop and icecube

IceTop-40/IceCube

Muon Bundle Energy Loss & Composition

T. Feusels et al.,

ICRC09

Data and H, Fe simulations

preliminary

Slant depth behavior of

muon bundle energy loss

Data: 28 days Sep 2008

Resolution, efficiency, systematics work in progress


Cosmic rays at the knee and above with icetop and icecube

IceTop-40 Near Threshold ~300 TeV

Restrict event selection

-- 3 station triggers

only nearby stations

forming triangle

-- 4 station triggers

only nearby stations

forming quadrangle

-- use flat shower front

-- use the same LDF

-- stronger containment


Cosmic rays at the knee and above with icetop and icecube

Proton MC

Iron MC

IceTop-40 Near Threshold ~300 TeV

Reconstructed

energy distribution

for H & Fe simulations

3 station events

3 stations

only

Data compared

with H & Fe

simulations

for zenith [0-26]°

4 stations

only


Cosmic rays at the knee and above with icetop and icecube

Summary

Work in Progress:

IceTop-26 2 PeV < E < 100 PeV

-- Unfolded Energy Spectrum using 5 months of data

-- Further exploit zenith angle dependence on composition

IceTop-40/IceCube coincidence 1 PeV < E < 50 PeV

-- Muon bundle energy loss measured in IceCube is sensitive to composition

-- simulations are limited beyond 50 PeV

IceTop-40 at threshold ~ 300 TeV

-- use 3 station events only

  • upgrade shower simulations  start using thinned CORSIKA showers beyond 50 PeV

  • upgrade detector simulation  calibrations better known than 2 yrs ago

  • re-work systematics