Atmospheric neutrino fluxes

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Atmospheric neutrino fluxes

• A background and an interesting measurement
• How well do we know the atmospheric neutrino
  fluxes?
• The primary CR spectrum
• Can we have a muon and neutrino flux from the
  same code?
• A tool for simulation and analysis a C class
  and a library
• for fluxes (suitable for ANIS and IceTray)
• It is a beautiful measurement with the largest
  data
• sample AMANDA (IceCube) have since K physics and
  prompt
• Fluxes are poorly constrained by accelerator data

Teresa Montaruli, Paolo Desiati, Aya Ishihara,
UW, IceCube Meeting, Mar 2005
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Super-Kamiokande and MACRO
TM, ICRC2003 HE rapporteur talk
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Primary CRs

• Primary spectra ICRC2001 (softer), Agrawal or
  Old Bartol (harder)

5 agreement between AMS and Bess98 CAPRICE -20 ICRC2001 assumes AMS-Bess The
region relevant for AMANDA/IceCube is
higly uncertain due to large errors of Jacee and
RunJob data Moreover He and heavy components are
worse known and their relevance increases
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The inputs primary CRs in most recent
calculations
Main difference between ICRC2001/Gaisser-Honda
2002 CNOSi-MgFe E-2.7/harder Main difference
between ICRC2001/HKKM 2004 He average of
E-2.74E-2.64/ E-2.64 protons E-2.74 /
E-2.74E-2.71 (E100 GeV) Results HKKM 2004 is
closer to previous Agrawal et al, 1996, harder
than ICRC2001 and Gaisser-Honda fit resulting in
more through-going muons
Gaisser-Honda 2002
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These results agree with Gaisser astro-ph/0502380
Theoretical Errors
Though HKKM 2004 uses a harder spectrum than
Bartol, it is lower! Interaction models are
different (Target 2/DPMJET-III to be updated
15 lower than L3 m data) Lots of comparisons
between Bartol, HKKM and FLUKA groups resulted in
uncertainty reduction also thanks to muon data
in the atmosphere. These groups published their
results in 2003-2004. Can AMANDA data help? How
does Lipari flux (used in AMANDA) compare to the
more recent calculations?
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AMANDA DATA
hep-ex/0501064
SK data prefer higher fluxes by 12 and harder
spectra than HKKM2004 0.05 100 GeV
AMANDA works in a higher E region where
oscillations play a small role BUT in the
region where hadronic models are worsely known (K
physics, prompts) Systematics need to be
reduced Paolos talk!!!!
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Atmospheric ns and ms with FLUKA
FLUKA (http//www.fluka.org) new runs extending
up to 106 GeV/nucleon started at UW. The goal is
to have neutrinos from 4p and atmospheric muons
from the same interaction and transport code
(first 3D code, Astr.Phys.19, 2003) Prompt
neutrinos and muons will be addressed when
DPMJET-III interface will be ready
FLUKA yet poor statistics L3 m data can
help reducing systm at HE
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The inputs primary CR for VHE spectrum
NEW FLUKA generation CR suitable for VHE
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The AtmosphericFlux Class

• The constructor AtmosphericFlux mymodel(model)
• Class Methods
• Init Read Tables in prepared in common
  format
• Flux returns the flux at a given energy,
  angle and for a flavor
• eg double flux mymodel.Flux(1,1.e3,0.1)
• returns flux in GeV-1 cm-2 sr-1 s-1 given
  
• Neutrino type ne, anti-ne, nm, anti-nm
• Neutrino Energy
• Cos(zenith)
• Average flux returns averaged over lower
  hemisphere
• Compatible with ANIS
• Usable by IceTray (A. Hishihara)
• Usable in analysis stage with ROOT as a shareable
  library
• Extensible to ANY FLUX (can become a library of
  fluxes to be used
• for event reweighting purposes)