Proc. Neutrino Astrophysics - MPP Theory Group

Entry
10 3
10 2
10
1
No fake for cos(zenith) < +0.1
MC Zenith
Reco Zenith
A eff = 10000 m 2
Rejection ≥ 1.6 10 5
-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1
COS(zenith)
Entry
10 2
10
1
Entries: 2637
Mean: 5.3
Median: 2.4
MPV: 1.7
125
Reconstruction error [ o 0 20 40 60 80 100 120 140 160 180
]
Figure 4: Performance expected for the 10 string AMANDA-B detector. The left figure
shows the zenith angle distribution of up-going muon events passing all quality cuts. In this
calculation minimum ionizing muons have been initially generated isotropically from the lower
hemisphere. The difference in reconstructed and generated muon directions are shown on the
right plot. A median accuracy of 2.4 ◦ is achieved.
significantly better compared to the 4-string installation. The data is currently being analysed.
Figure 4 shows results from a full Monte Carlo calculation. With background suppression
(S/N > 10 5 ) an effective area of the order of 10 · 10 3 m 2 and a median angular resolution of
2.4 ◦ is achieved. Several atmospheric neutrinos per day should be detectable [3].
The full AMANDA-II detector is aimed to be installed until the year 2000. It should reach
effective areas from 50 · 10 3 m 2 to 100 · 10 3 m 2 . It is thus almost two orders of magnitude
more sensitive than current detectors. The angular resolution is expected to be of the order
of 1 ◦ [4].
Towards ICECUBE
First experiences with data of a km scale telescope have already been gathered in 1996 with
coincidences between the shallow AMANDA-A and the deep AMANDA-B detector [1, 2, 4].
The purpose of the current AMANDA-II installation campaign is to monitor the depth profile
of optical properties from 1200 m down to 2500 m. The tests of a large variety of technical
issues will help to define a robust technology, which is suitable for the construction of the large
km 3 scale telescope. Besides the tests of different PMTs, optical fibres and connectors also
wavelength-shifters (to improve the UV sensitivity) and other strategies for signal processing
(Digitising optical modules) are tested [4].
A straw-man ICECUBE detector might consists out of 60 additional 1 km long strings,
each with 70 OMs. Based on the experience from AMANDA-B and AMANDA-II the prices
per channel may be estimated to 6 k$. This includes the optical module, cables, calibrations
sources, surface electronics (DAQ) and workshop labour. Adding 5 M$ for off-line computing
and additional detector components the bare detector price would be of the order of 30 M$ [4].