A. Karle UW Madison 1. 2 Why neutrino astronomy? Astrophysical Accelerators Neutrinos allow for...
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Transcript of A. Karle UW Madison 1. 2 Why neutrino astronomy? Astrophysical Accelerators Neutrinos allow for...
A. Karle UW Madison
2
Why neutrino astronomy?Astrophysical Accelerators
Neutrinos allow for observation of ‘hidden regions’ of cosmic accelerators (BH, pulsars, initial epochs of SN explosions). The penetrating power of νs is important also for moderately opaque sources from which we may be seeing ϒ spectra that are significantly distorted
DM annihilation CasA Supernova Remnant in X-rays
Accretion disk with jets
A. Karle UW Madison
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Drilling experience
AMANDA drilling (1950m) 90 hrs
IceCube drilling (2450m) 35 hrs
Thermal power: 5MW
NSF, Aug 7, 2007 Tom Gaisser, IceCube Status 4
Detector reliability
• Very good survival rate during installation.
• 98.5% of all deployed sensors are commissioned and being used in the first science run.
• In 1000 DOM years of accumulated live time only 2 sensors failed after commissioning.– Estimated survival rate after 15 years: 97+1.5
-3.5%– Estimate based on the assumption of a constant failure rate.
A. Karle UW Madison
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IceCube Laboratory and Data Center
Commissioned for operation in January 2007.
3 Winter-over scientists operate and maintain instrument during winter
Only two winter-overs planned for 2008
17 racks of electronics
Power: 60 kW total for full IceCube
NSF, Aug 7, 2007 Tom Gaisser, IceCube Status 6
IceCube 22: 2007 operation since “physics” start
• May 23, run 107868 until July 30, run 108975– 95.9% uptime– Trigger
• In-ice: > 7 hits in 5 s• IceTop > 5 hits in 2 s
– Typical rates:• in i3+AMANDA(twr) mode: 610 Hz• In i3-only: 525 Hz
• Since start of I3 physics filtering (July 7 - now):– 99.4% uptime (special ops –like CV flashing- while running
at least partial I3 detector)• Data
– 200 GBytes/day raw data written to disk– 25 GBytes/day filtered and sent north via satellite– Monitoring files posted daily at http://icecube.berkeley.edu/i3-
monitoring/2007/monitor.shtml
NSF, Aug 7, 2007 Tom Gaisser, IceCube Status 7
List of deployed filters (31/07/07)
Name in FilterMask Prescale (1/N) Summary of event selection
IceCubeMuonFilter 1 (Linefit.theta >= 70.0 and NChannelInIce >=10) OR
(Linefit.theta >= 60.0 and NChannelInIce >=40)
CascadeFilter 1 TensorOfInertia.evalratio>.109 and Linefit.velocity<.25
(all based on LCSpan 1)
EHEFilter 1 NChannelInIce >= 80
MoonFilter 1 No events currently selected (moon down)
LowEnergyContainedFilter 1 Linefit.velocity (0.1,0.5) & NChannelInIce < 16 &
Many Others (see proposal)
IceTopSMT 5 Any event with an IceTop SMT trigger present
IceTopSMT_Large 1 Any event with NChannelIceTop >= 16
IceTopSMT_InIceCoincidence 1 Any event with BOTH InIce SMT and IceTop SMT
triggers present
InIceSMT_IceTopCoincidence 5 Any event with an InIce SMT and any IceTop station
hit
FilterMinBias 200 Any event seen in the JEB.
NSF, Aug 7, 2007 Tom Gaisser, IceCube Status 8
Offline Data Flow
From Pole to North by satellite
Physics analysis
Dec
om
pre
sse
d
Cal
ibra
ted
Ref
ilter
ed
9
IceTop
InIce
Air shower detector
80 pairs of ice
Cherenkov tanks
Threshold ~ 300 TeV
Goal of 80 strings of 60
optical modules each
17 m between modules
125 m string separation
2004-2005 : 1 string
2005-2006: 8 strings
AMANDA-II
19 strings
677 modules
2006-2007:
13 strings deployed
IceCubeCurrent configuration- 22 strings- 52 surface tanks
Completion by 2011.2007/08: add 14 to 18 strings and tank stations
1450m
2450m
AMANDA now operating as part of IceCube
NSF, Aug 7, 2007 Tom Gaisser, IceCube Status 10
IC22 Events
Downward cosmic-ray event (“muon bundle”) Upward candidate event
( Red hits = early; yellow/green/blue = later ) IceCube DOM locations blue, AMANDA OM locations red
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Azimuth distributions: IC9 and IC22
Downgoing muons.
Azimuth distribution illustrates detector response.
At lower energies one can see azimuthal structure due to detector geometry.
Rate for 22 strings~4 times higher
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IC22 - Online zenith distribution
Zenith distribution is compared to simulations. (Crosses: data, line: MC, normalized)
Events with zenith angle > 80° pass online filter and are sent to North.
(There are numerous other filter streams, eg. Nu_e and nu-tau, GRB, WIMPs, …)
Cos(zenith)
NSF, Aug 7, 2007 Tom Gaisser, IceCube Status 13
IceTop – 2 tanks per station
Preliminary energy spectrum with 2006 data
NSF, Aug 7, 2007 Tom Gaisser, IceCube Status 14
Reconstruction of big, coincident event: E ~ 0.5 EeV by IceTop
0.5 EeV ~2000 at 2.5 km
NSF, Aug 7, 2007 Tom Gaisser, IceCube Status 15
Cosmic-ray physics with IceCube
• Measure spectrum/composition– from <1 PeV to >1 EeV– IceTop alone– In-Ice alone (muon bundles)– Hybrid, coincident events
• Calibration with IceTop tagged events• Measure physics background
– Muons and muon bundles
NSF, Aug 7, 2007 Tom Gaisser, IceCube Status 16
Atmospheric with IceCube-9
Note severe cuts needed to reject background with only 9 strings.Situation will improve as detector grows
Phys. Rev. D (to be published)arXiv:0705.1781
NSF, Aug 7, 2007 Tom Gaisser, IceCube Status 17
Growth of detector
AMANDA ANTARES
+IC9
+IC36-40+IC22
Full IceCube 2011
Km3Net
NSF, Aug 7, 2007 Tom Gaisser, IceCube Status 18
IC 9 in 2006
Point source catalog• Many involve jets • IC-9 point source search reported at ICRC2007
NSF, Aug 7, 2007 Tom Gaisser, IceCube Status 19
Point source search, example: MILAGRO MGRO2019+37 in Cygnus
Note: small signal with signal/background ~1
Photon flux: data & model fits to MGRO J 2019 +37
NSF, Aug 7, 2007 Tom Gaisser, IceCube Status 20
IceCube Sensitivity
• IC9 sensitivity ~10-7 GeV-1 cm-2 s-1 (EGeV)-2
– ~2 orders of magnitude above predicted signal from MGRO J2019 +37
– Cuts remove large fraction of signal (90% for atmospheric spectrum, less for harder spectrum)
• Sensitivity grows faster than detector size– For example, IC22 sensitivity is 4-5 times IC9
while size ratio is 2.5– Angular resolution improves with longer tracks
NSF, Aug 7, 2007 Tom Gaisser, IceCube Status 21
Expectations for point source search with IceCube
• Expected signals small– < few events per year– Background of atmospheric in search bin
comparable to expected signal– Optimize search techniques
• Unbinned searches • Sensitivity to expected hard spectrum• Source stacking
• Multi-messenger approach:– Use correlation with physically related
variability in multi-wavelength data – Examples: flaring AGNs; GRB
NSF, Aug 7, 2007 Tom Gaisser, IceCube Status 22
Multi-messenger/multi-wavelength
• Coordination with MAGIC, VERITAS, HESS…• Two IceCube talks this week at
• Optical follow-up scheme proposed– Like ROTSE to look for GRB afterglow or SN light
curve or choked GRB– Trigger on 2 or more in time/direction window
• Two guest investigator proposals to GLAST
NSF, Aug 7, 2007 Tom Gaisser, IceCube Status 23
Search for neutrinos from GRB
Cascade(Trig & Roll)
Cascade(Rolling)
search
All flavor limits by AMANDAGRB models
Waxman-BahcallPRL 78 (1997) 2292
Murase-Nagataki APRD 73 (2006) 063002
Supranova,Razzaque et al.PRL 90 (2003) 241103
Choked burstsMeszaros-WaxmanPRL 87 (2001) 171102
Limits on neutrinos from GRB from AMANDA: -from cascades (e, ), Ap.J. 664 (2007) 397-from neutrino-induced muons, Ap.J (to be published)
NSF, Aug 7, 2007 Tom Gaisser, IceCube Status 24
Prospects for detecting GRB ’s with IceCube
• AMANDA limits– Already disfavor some models– Sensitivity close to classic Waxman-Bahcall
fireball prediction (expected ~ 1 in 400 GRBs)• IceCube sensitivity ~20 times AMANDA
– 200 GRB / yr expected from GLAST– Expect 3 detection of Waxman-Bahcall level in
70 GRB with full IceCube– Non-observation would indicate GRB jets are
pure Poynting flux (Blandford) rather than baryon loaded plasma (Piran, Meszaros, …)
NSF, Aug 7, 2007 Tom Gaisser, IceCube Status 25
Cascades—a way to avoid background of atmospheric
Neutral Current (NC) : X N X X , where x = e, ,
Charged Current (CC) : e N e X N X
M.Kowalski [astro-ph/0505506Atmospheric -induced cascade events:- 9-strings: 10 events / year- 22-strings: 30 events / year
Prompt -induced cascades from charm- 15 events/year with 22 string-array
Diffuse extraterrestrial neutrino flux (expected from AGNs or GRBs)
- With 22 strings Waxman-Bahcall rate (with source evolution) E2<5x10-8 GeV-1sr-1s-1 may be detectable
NSF, Aug 7, 2007 Tom Gaisser, IceCube Status 26
Take advantage of -oscillations: use the channel
• No atmospheric background
• But rare, ~1 event / yr in full IceCube
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AMANDA+IC22:Improves low-energy capability for point source search
including from WIMP annihilation in Sun
AMANDA+IC22AMANDA
Angular Resolution Effective Area
AMANDA gives to IceCube more area at lower energyfrom ~ 100 GeV
IceCube gives to AMANDAa better angular resolution up to ~ 50 TeV
Optimization scheme in order to fight atmospheric neutrinos (dominant at this energy):- Search for from dark matter- X-ray Binary: energy spectrum and time characteristic- Pulsar Wind Nebulae: energy spectrum - SNr near Molecular Clouds: stacking
AMANDA+IC22
IC22
preliminary
preliminary
NSF, Aug 7, 2007 Tom Gaisser, IceCube Status 28
AMANDA/IceCube as MeV detector…first proposed by Halzen, Jacobsen & Zas, astro-ph/9512080
PMT noise low (~ 300 Hz) ice uniformly illuminated
detect correlated rate increase on top of PMT noise
NSF, Aug 7, 2007 Tom Gaisser, IceCube Status 29
Supernova watch with IceCube
• IceCube SN DAQ– Now running with 1300 DOMs
– Total noise rate shown • Connection to SNEWS
– Planned for 07/08 season
– Depends on good monitoring
• Sensitivity– Example shows SN at gal. cntr. – Good probability of detection out
to LMC
IceCube deployment 2005-2011AMANDA
IceCube string and IceTop station deployed 12/05 – 01/06
IceTop station only 2006
2560 DOMs deployed to date
ONLY 3 ? FAILED SO FAR
3 more seasons planned
Crucial planning period during the next 4 – 6 months
21
3029
40
50
3938
4748
49
595857
6667
74
65
73
7778
46
56
72
IceCube string and IceTop station deployed 01/05
IceCube string and IceTop station deployed 12/06 – 01/07
71
64
55
IceTop station only in 06 / 07
7576
7069
68
6362
6160
5354
52
4544
Deployed in 07 / 08
2004 / 05
2005 / 06
2006 / 07
2007 / 08
NSF, Aug 7, 2007 Tom Gaisser, IceCube Status 32
Detector operation(Snapshot as of 31-07/07)
PnF Physics Filter Rates
Filter Hz Filter Hz
CascadeFilter 17.6188 EHEFilter 1.2611
FilterMinBias 2.57963 IceCubeMuonFilter 19.0078
IceTopSMT 2.51175 IceTopSMT_InIceCoincidence 2.2141
IceTopSMT_Large 0.832898 InIceSMT_IceTopCoincidence 2.09922
JAMSMuonFilter 0 LowEnergyContainedFilter 3.95822
MoonFilter (*) 0 MuonFilter 19.0078
Latest Status from Experiment Control
*Moon data is taken only when it is > 15 degrees above horizon
NSF, Aug 7, 2007 Tom Gaisser, IceCube Status 35
Point source search with IC9
IC9 Neutrino effective area (Dumm, Finley & Montaruli, ICRC2007)
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Photon data: light curves combination
Elisa Resconi
M. Tluczykont, M. Shayduk, O. Kalekin, E. Bernardini
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What do we gain? Analysis cuts re-optimized using the blocks distribution For the moment NO energy spectrum optimization (to be come soon) How does it look like the Detection Probability ??
Preliminary
NSF, Aug 7, 2007 Tom Gaisser, IceCube Status 39
Optical follow-up
Teresa Montaruli for Multi-wavelength conference, Adler Planetarium, Aug 9
NSF, Aug 7, 2007 Tom Gaisser, IceCube Status 40
Take advantage of -oscillations: use the channel
• No atmospheric background
• Assume diffuse flux at AMANDA limit– 3 x Waxman-Bahcall limit– A total of ~0.48 events per year is
expected for all tau signature in IC-22 • Lollipops: ~0.16 events per year• Inverted Lollipops: ~0.19 per year• Double Bangs: ~0.13 per year
July 22, 2007 Tom Gaisser 42
Local coincidence count rates versus depth (std. occupancy plot)
Note that rates are lower in this standard occupancy plot-- Note: SMT >= 8 per string is required