G.Barbiellini et al. TeV CR with GLAST

GLAST LAT GLAST Italian SW meeting 11 march 2004

TeV CR compositionTeV CR composition with GLASTwith GLAST Guido Barbiellini, Valter Bonvini, Mirko Boezio, Francesco Longo, Andrea VacchiUniversity and INFN, Trieste, Italyguido.barbiellini@ts.infn.itA.Deangelis et al. University of Udine and INFN, TriesteG.Busetto et al., University and INFN PadovaP.Spinelli et al., University and INFN, Bari…

G.Barbiellini et al. TeV CR with GLAST

GLAST LAT GLAST Italian SW meeting 11 march 2004

OutlineOutline

• Brief introduction– CR spectrum at the knee– ACCESS

• CR measurements at TeV– The concept (NUCLEON proposal)

• Preliminary calculations– Events per day with GLAST

G.Barbiellini et al. TeV CR with GLAST

GLAST LAT GLAST Italian SW meeting 11 march 2004

G.Barbiellini et al. TeV CR with GLAST

GLAST LAT GLAST Italian SW meeting 11 march 2004

SNR shock accelerationSNR shock acceleration

• Emax ~ shock Ze x B x Rshock

Emax ~ Z x 100 TeV with exponential cutoff of each component

– But spectrum continues to higher energy: Emax problem

G.Barbiellini et al. TeV CR with GLAST

GLAST LAT GLAST Italian SW meeting 11 march 2004

Knee of spectrumKnee of spectrum

• Differential spectral index changes at ~ 3 x 1015eV

– – Continues to 3 x 1018 eV

– Expect exp{-E / Z Emax} cutoff for each Z

• Fine-tuning problem:

– To match smoothly a new source with a steeper spectrum

Knee

G.Barbiellini et al. TeV CR with GLAST

GLAST LAT GLAST Italian SW meeting 11 march 2004

Speculation on the kneeSpeculation on the knee

K-H Kampert et al., astro-ph/0204205

Total

protons

helium

CNO

Mg…

Fe

1 1 Component: = 2.7, Emax = Z x 30 TeV; Emax = Z x 1 PeV

3 components

G.Barbiellini et al. TeV CR with GLAST

GLAST LAT GLAST Italian SW meeting 11 march 2004

AccessAccess

G.Barbiellini et al. TeV CR with GLAST

GLAST LAT GLAST Italian SW meeting 11 march 2004

AccessAccess

• Element identifier dimensions: 2m x 2m x 0.3m – Silicon solid state detector array 4 layers – Aerogel Cherenkov detector – Plastic Cherenkov detector – Scintillating optical fiber hodoscope

• Relativistic velocity identifier dimensions: 1.7m x 1.7m x 1.2m – Transition radiation (TR) detector composed of

• 6 layers of TR radiating blankets • 12 layers of Xe filled proportional tubes

• Energy identifier dimensions: 1m x 1m x 0.8m – One interaction length of carbon target – 30 radiation lengths of BGO (Bismuth germanate

scintillator)

G.Barbiellini et al. TeV CR with GLAST

GLAST LAT GLAST Italian SW meeting 11 march 2004

NUCLEON NUCLEON

G.Bashindzhagyan et al. ICRC 2003

G.Barbiellini et al. TeV CR with GLAST

GLAST LAT GLAST Italian SW meeting 11 march 2004

NUCLEON testsNUCLEON tests

G.Bashindzhagyan et al. ICRC 2003

G.Barbiellini et al. TeV CR with GLAST

GLAST LAT GLAST Italian SW meeting 11 march 2004

NUCLEON testsNUCLEON tests

G.Bashindzhagyan et al. ICRC 2003

G.Barbiellini et al. TeV CR with GLAST

GLAST LAT GLAST Italian SW meeting 11 march 2004

NUCLEON simulationNUCLEON simulation

A.N. Turundaevsky et al. ICRC 2003

G.Barbiellini et al. TeV CR with GLAST

GLAST LAT GLAST Italian SW meeting 11 march 2004

GLAST for CR?GLAST for CR?

• CR spectrum:

• GLAST surface : ~3m2

• Solid Angle: ~ 2 steradians• Energy of 1 event per day

(with optimal efficiency)• Energy of 1 event per 100 days

(with optimal efficiency)

7.211124105.1 GeVEGeVstsm

GeVE

E

E

GeV

GeV

3

10547.2

105

10log7.2

10106105.1

GeVE

E

E

GeV

GeV

4

12747.2

103

12log7.2

10106105.1

G.Barbiellini et al. TeV CR with GLAST

GLAST LAT GLAST Italian SW meeting 11 march 2004

Work in progressWork in progress

• The concept– Charge by dE/dx before interaction– Energy deposit and secondary transverse profile after

interaction• GLAST simulation

– G3 preliminary (with CR interaction)– G4 full with trigger

• Test Beam evaluation• Caveats

– Efficiency– Electronics