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David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICERadio Ice Cherenkov Experiment
PI
presenter
David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICENeSS: 10 min + 2
• Concept
• Status
• Results (astro-ph/0206371)
• Future
David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICERadio Detection of High Energy Neutrinos
Goals
PeV: AGN 1 km3
EeV: GZK 103 km3
Cherenkov radiation from induced in-ice shower
Signal ~ Q ~ 0.25 Es/GeV ~ RM ~ 10 cmTransparency > 1 kmThermal noise @ 250 k
.8 km
David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICEEeV neutrino detection with RICE
5 km
1-10 PeV 1-10 EeV _
Signal Strength Ice PropertiesCalibration LPM effecte e N recoil hadrons0s interact
David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICE
• 16 Rx (10 cm dipole)• 5 Tx• 3 Horns• 4 Oscilliscopes (x4) • DAQ• PCs• Pulse Generator• Dry hole
Pole:
• Network analyzer• Antenna range
Kansas:
Deployment
David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICEChannel and DAQ configuration
Power
Scope
Trigger generator
Antenna
Amp in PV
cableAmpFilter
Splitter
PC• 4 hits within 1200 ns • Latch scope• TDC times to PC • On-line veto (TDC times)
• Read scope• Write to disk
• 8 sec• 1 ns sample• 500 MHz
David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICESingle Channel Calibrations
200-500 MHz: +/- 3 dB (E)
TX….RX • antenna + amplifier calibrations• cable (TX, RX) and filter• relative geometry of TX/RX (r,
David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICEMonte Carlo Simulation
• Neutrino interaction
• e+/e-/ shower
• Radio pulse generation
• Propagation through ice
• Antenna & DAQ response
David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICEInteractions and Event types
• Interaction Model– isotropic flux from upper hemisphere (2sr)
– charged and neutral currents
– hadronic energy = y E, lepton energy = (1-y) E
– Gandhi et al. ’98 cross-sectiond/dy with ~20% reduction for Oxygen (EMC effect)
David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICEShower Simulations
• Shower simulation– GEANT 3.21 (100 GeV – 1 TeV)
30% smaller than ZHS (but …GEANT 4 ??)
– Extrapolate to higher energies
– LPM from Alvarez & Zas
– Hadronic cascades convert
completely to EM with no
LPM
– EM & hadronic cascades
treated separately
Average 100 GeV shower
David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICEEM Pulse generation
ALSO: Experimental results (Saltzberg, et al.) confirms coherence and Askaryan effect
1. Pulse increases with Energy2. Narrows with frequency3. Some small numerical
differences between codes
David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICERadio Attenuation in Ice
Red – Westphal (Greenland) + Matsuoka (high freq)Black – Kawada(lab) + Matsuoka (high freq) (from Matsuoka)
0.1 0.2 0.5 1 2 5 10nHGHzL
0.0005
0.001
0.002
0.005
e''
temp = - 10
0.1 0.2 0.5 1 2 5 10nHGHzL0.0001
0.000150.00020.00030.00050.00070.001
0.00150.002
e''
temp = - 25
0.1 0.2 0.5 1 2 5 10nHGHzL0.00002
0.00005
0.0001
0.0002
0.0005
e''
temp = - 50
’ + i”
0.1 0.2 0.5 1 2 5 10nHGHzL
0.1
1
10
100
1000
lttaHmkL
lH- 60 CLx 100
lH- 50 CLx 10
lH- 40 CLx 1
Solid – Provorov (used by RICE)Dashed – Matsuoka + Westphal
RICE bandpass
David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICEPulse shape simulation
Disc. threshold
Background taken from data sample
David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICEResults of MC simulation
Limited by attenuation
60,000 e- showers at E = 1 EeVBlack dots – sampleRed dots – events which would trigger RICE
~ 5% efficiency
Limited by Cherenkov angle
David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICE
1. 2. 3. 4. 5. 6.Log@EsDHPeVL- 3.
- 2.
- 1.
0.
1.
2.
goL@V ffeDHmk3 L
RICE effective volume for e-, showers
Range due to varyingsignal strength by 0.5-2
Range due to varyingattenuation by 0.5-2
Mul
tipl
y by
2
sr
This is appropriatefor e chargedcurrent events.
David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICE
1. 2. 3. 4. 5. 6.Log@EsDHPeVL- 3.
- 2.
- 1.
0.
1.
2.
goL@V ffeDHmk3 L
LPM and hadronic showers
With LPMWithout LPM
“Hadronic”Es = 20% E
David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICEReconstruction of transmitter events
• t =50 ns for noise• t = ns for
• r = 10 m nearby• r = 0.1 R , < 1 km
• ~ 10 deg• E/E ~ 0.5
David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICEResults of Data Analysis
333.3 hrs livetime
David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICELimits on diffuse e flux from e- showers
a) Stecker & Salamon (AGN)b) Protheroe (AGN)c) Mannheim (AGN)d) Protheroe & Stanev (TD)e) Engel, Seckel & Stanev (GZK)
Ranges are central 80%
David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICELimits derived from e- showers (e CC)hadronic showers (all CC+NC)
a) Stecker & Salamon (AGN) d ) Protheroe & Stanev (TD)b) Protheroe (AGN) e) Engel, Seckel & Stanev (GZK)c) Mannheim (AGN)
Ranges are central 80%
David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICENear term future
Beginning analysis of ~ 1 yr of data. Improve limits by ~ 10.
David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICELonger term
100 GZK events/yr requires ~ 1000 km3 (1 Eg)
RICE: LPM no LPM
Auger: tau e, muLPM
LPM
Needs
SaltEUSO
ANITA
AMANDA/ANTARES
IceCube/NEMO
David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICESummary
• Radio detection has a bright future• Demonstrated ability to reject surface backgrounds and work close to
thermal limit• Major uncertainty is
– attenuation in ice (high energy)– calibration (low energy)
• Veff (E > 1018eV) > 20 km3 sr [e CC only]• Limit improves by 2-18 with inclusion of hadronic channels,
depending on spectrum.• Limits may improve by 10 (again) with analysis of 1 yr data.• 100 GZK events per yr is conceivable
David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICE
Intentionally left blank
End of Talk
David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICEThermal Background
-4 -2 0 2 4
-4
-2
0
2
4
-0.8 -0.4 0.0 0.4 0.8
-0.8
-0.4
0.0
0.4
0.8
y (k
m)
x (km)
y (k
m)
x (km)
Red – Simulated detected showers (1 EeV)Black – Simulated noise – uncorrelated background
Warnings: shower vertices are “true” positions not reconstructed. Should be OK inside 1 km.shower vertices are monoenergetic.
David Seckel, NeSS02, Washington DC, Sept. 19-21,/2002
RICESystematic Effects (see astro-ph/0206371)
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