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results from neutrino telescopes. Carlos de los Heros , Uppsala University. COSMO05. Bonn, Aug. 28 – Sep. 1, 2005. Outlook. as a framework : high energy neutrino astronomy the world of neutrino telescopes: current projects recent physics results from AMANDA and Baikal
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results from neutrino telescopes Carlos de los Heros, Uppsala University COSMO05. Bonn, Aug. 28 – Sep. 1, 2005
Outlook. • as aframework: high energyneutrino astronomy • the world of neutrino telescopes: current projects • recent physics results from AMANDA and Baikal • ICECUBE: status and capabilities • summary
T. Gaisser 2005 proton accelerators ? neutrino astronomy • nature accelerates particles to ~10 7 times the CM energy of LHC! acceleration sites must sit somewhere candidate sources: • SNe remnants, mquasars • active galactic nuclei • gamma ray bursts • guaranteed sources: • atmospheric neutrinos (from p& K mesons decay) • galactic plane: • CR interacting with ISM, concentrated on the disk • CMB (diffuse): • UHE p g D+ n p+ (p p0)
your favourite cosmicaccelerator p g n your favourite detector particle propagation in the Universe • production: • neutrino production at source: • p+orp+pcollisions give pions: • p -> mn + nmmn -> e- + nm+ ne • neutrino flavors:e : : 1:2:~0 at source. Expect 1:1:1 at detector • propagation: • photons:can be absorbed on intervening • matter or radiation; • protons:deviated by magnetic fields • at high-enough energies: • p and g react with the CMB bckgr. • n’s will get to you • however: • n’s extremely difficult to detect!
Outlook. • as aframework: high energyneutrino astronomy • the world of neutrino telescopes: current projects • recent physics results from AMANDA and Baikal • ICECUBE: status and capabilities • summary
BAIKAL KAMCHATKA SALSA GLUE AUTEC ANTARES SADCO NESTOR NEMO AMANDA / ICECUBE RICE, ANITA current HE neutrino detection efforts OPTICAL RADIO ACOUSTIC @ extremely high energies (E>1018 eV)
signatures O(km) long muon tracks O(10m) cascades, nentneutral current neutrino detection in ice/water event reconstruction by Cherenkov light timing: need array of PMTs with ~1ns resolution optical properties of the medium of prime importance longer absorption length → larger effective volume longer scattering length → better pointing resolution neutrino astronomy possible since
the BAIKAL detector NT-200 - 8 strings with 192 optical modules - 72 m height, 1070 m depth - meffective area >2000 m2(E>1 TeV) - Running since 1998 4 Km to shore • NT-200+ • - commisioned April 9, 2005. • - 3 new strings, 200 m height • 1 new bright Laser for time calibration • imitation of 20TeV-10PeV cascades, • >10^12 photons/pulse w/ diffusor, • - new DAQ • 2 new 4km cables to shore NT200+ is tailored to UHE n-induced cascades 5 Mton equipped volume; V_eff > 10 Mton at 10 PeV
the AMANDA detector AMANDA-B10 - 10 strings with 302 optical modules - 450 m height, 1500 m depth - data years: 1997/99 AMANDA-II - 19 strings, 677 OMs - running since 2000 - new DAQ with FADC since 2003 Optical Module since March 2005 we are called IceCube! (AMANDA and IceCube collaborations merged) PMT noise: ~1 kHz
the site South Pole your daily commute to work Station facilities AMANDA 1500 m Amundsen-Scott South Pole station 2000 m [not to scale]
AMANDA-B10 time average flux upper limit [cm-2s-1] AMANDA-II sin(d) AMANDA detector performance • muons: • directional error:1.5° - 2.5° • s(log(Ereco/Etrue)):0.3 – 0.4 • coverage:2 • cascades:(e±, , neutral current) • zenith error:30° - 40° • s(log(Ereco/Etrue)):0.1 – 0.2 • (5TeV < E < 5PeV) • coverage:4 • m effective area:>10000 m2 for Em>1TeV Average upper limit = sensitivity (δ>0°) (integrated above 10 GeV, E-2 signal)
Outlook. • as aframework: high energyneutrino astronomy • the world of neutrino telescopes: current projects • recent physics results from AMANDA and Baikal • ICECUBE: status and capabilities • summary
in this talk: • AMANDA (and Baikal when available) results from: • atmospheric neutrinos • searches for anextra-terrestrial n flux: • galactic center • diffuse (anytime, anywhere) • point source (anytime, somewhere) • transient (known ‘flary’ objects & GRBs) (sometime, somewhere) • search forWIMPs: Excess from the center of the Sun/Earth agreed AMANDA collaboration strategy: analyses are done ‘blind’. cuts optimized on a % of data or on a time-scrambled data set.
test beams: atmospheric muons cosmicray muons atmospheric muons: -AMANDA test beam: Im vs depth, CR composition - background for other searches • SPASE (scintillator array @ 3000m) • e density @ surface • shower core resolution: 0(m) • shower direction resolution: < 1.5o • AMANDA • m‘s @ >1500m(>300 GeV @ surface) • use SPASE core position for combined fit • combined SPASE-AMANDA ‘detector’: • - probes hadronic (m) and EM (e) component • of the primary shower • - s(E) ~ 0.07 in log(Eprim) • - results compatible with composition • change around the knee • - sources of systematic uncertainties: • (~30% in ln(A), not shown in the plot) • -shower generation models • -muon propagation EHadron E-2.7 0.02
horizontal vertical Frejus AMANDA test beams: atmospheric neutrinos atmospheric neutrinos: -guaranteed test beam - background for other searches first spectrum > 1 TeV (up to 300 TeV) - matches lower energy Frejus data ► reconstruct energy of up-going μ`s ► obtain nenergy spectrum from regularized unfolding • set limit on cosmic neutrino flux: • how much E-2 cosmic ν - signal • allowed within uncertainty of • highest energy bins? limit on diffuse E-2νμflux (100 -300 TeV): E2μ(E) < 2.6·10–7 GeV cm-2 s-1 sr-1
- Gaus. limit - model - - - - - n’sfrom the galactic plane • location of AMANDA not optimal reach only outer region of the galactic plane: 33o<d<213o • three signal ansatz: • line source, Gaussian source, diffuse source • limits include systematic uncertainty • of 30% on atm. flux • energy range: 0.2 to 40 TeV data sample 2000-03: 3369nevts:
analyses optimized for nm (reduced sensitivity to ne and nt ) • HE: TeV < En < PeV • search confined to up-going tracks • UHE: En > PeV • Earth opaque: search in the upper hemisphere and close to the horizon all-flavour • Cascades: TeV < En < PeV • 4p sensitivity search for HE neutrinos from the cosmos energy regions: • strategies in the search for point sources: • diffuseflux with no time-space correlations. • from high energy tail of atmosphericνμ • selection with emphasis on background(s) rejection • spatial correlation with steadyobjects • search for clusters of events (w. or w.o. catalogue) • stacking of same-type of point source candidates • space and/or time correlation with transient phenomena • known active flary periods of TeV gamma sources • coincidence with GRBs
7 8 6 diffuse flux search AMANDA 1: B10, 97, ↑μ 2: A-II, 2000, atmosph. n 3: A-II, 2000, cascade 4: B10, 97, UHE 6: A-II, 2000, UHE sensit. 7: A-II, 2000-03 ↑μ sensit. Baikal 5: 98-03, cascades 8: NT200+ sensitivity to ne limits for other flux predictions: - cuts optimized for each case. - expected limit from a given model compared with observed limit. some AGN models excluded at 90% CL: Szabo-Protehoe 92. Proc. HE Neutr. Astrophys. Hawaii 1992. Stecker, Salamon. Space Sc. Rev. 75, 1996 Protheroe. ASP Conf series, 121, 1997 all-flavor limits 1:1:1 flavor flux ratio
1ES1959 Cyg-X3 Cyg-X1 Mk421 Mk501 crab M87 SS433 search for clusters of events in the northern sky significance map event selection optimized for both dN/dE ~ E-2 and E-3 spectra data from 2000-2003 (807 days) 3369 n from northern hemisphere 3438 n expected from atmosphere • search for excesses of events on: • the full Northern Sky • a set of selected candidate sources … out of 33 Sources
neutrino sky from Baikal 1998-2002 data sample -372 events - 385 evts expected - no indication of clustering
time search for’scorrelated with GRBs low background analysis due to both space and time coincidence search! Off-Time Always Blind Precursor On Time 10 min 1 hour 1 hour 110 s T90 • catalogues: BATSE+IPN3 • bckg. Stability required within ±1 hour from burst • several search techniques: • coincidence with T90 • precursor (110s before T90) • cascades (all flavour, 4p!) • -coincident with T90 • -rolling time window • (no catalogue)
search for DM candidates in the Sun/Earth • Wm 20%, Wb 5% • non-baryonic matter MSSM candidate: the neutralino, c • may exist as relic gas in the galactic halo gravitational accumulation in Sun/Earth makes ‘indirect’ searches with neutrino telescopes possible neutralino-induced neutrinos: qq cc l+l- n W,Z,H signature: n excess from Sun/Earth’s center direction A lot of physics (ie. uncertainties) involved: - relic density calculations - DM distribution in the halo - velocity distribution - c properties (MSSM) - interaction of c with matter (capture)
2001 results from indirect DM searches search for a neutralino signal from the Earth search for a neutralino signal from the Sun Sun analysis possible due to improved reconstruction capability for horizontal tracks in AMANDA-II compared with B10.
other particle searches 10-14 e.g. magnetic monopoles: Cherenkov-light (n·g/e)2 (1.33*137/2)2 8300 times brighter than ‘s! signature: ‘slowly‘ moving bright particles Soudan KGF Amanda-B10 10-15 MACRO Orito upper limit (cm-2 s-1 sr-1) 10-16 Baikal 2005 electrons 10-17 1 km3 10-18 0.50 0.75 1.00 = v/c
Outlook. • as aframework: high energyneutrino astronomy • the world of neutrino telescopes: current projects • recent physics results from AMANDA and Baikal • ICECUBE: status and capabilities • summary
the IceCube observatory: IceCube+IceTop 1200 m surface array: IceTop • 80 stations air shower array (one per IceCube string) • similar station concept as Auger • 2 tanks (2 DOMs each) per station • 125 m grid, 1 km2 at 690 g/cm2 IceTop IceCube deep ice array: IceCube • digital readout technology (DOMs) • 80 strings, 60 DOM’s each • 17 m DOM spacing • 125 m between strings • hexagonal pattern over 1 km2x1 km
e e “cascade” Em=6 PeV En = 375 TeV ~300m @ Et = 1 PeV IceCube: an all-flavor neutrino telescope m m • background • mainly downgoing bundles • (+ uncorrelated coincident 's) • - exp. rate at trigger level ~1.7 kHz - atm. rate at trigger level ~300/day • IceCube will be able to identify • - tracks from for E > 100 GeV • - cascades from e for E > 10 TeV • - for E > 1 PeV
Galactic center IceCube: Aeff and resolution Em< 1 PeV: focus on the Northern sky, E > 1 PeV: sensitive aperture increases with energy full sky observations possible
IceTop Stations with DOMs – January 2004 digitized muon signals from DOMs signal, freeze control, temperature control cables Amplitude (ATWD counts) vs time (ns) power cable
IceCube first string: january 2005 27.1, 10:08: Reached maximum depth of 2517 m, reversed direction, started to ream up 28.1, 7:00: drill head and return water pump are out of the hole, preparations for string installation start 7:52: Handover of hole for deployment 9:15: Started installation of the first DOM (DOM 60) 12:06: 10th DOM installed 22:36: 60th DOM installed Typical time for DOM installation:12 min 22:48: Start drop 29.1, 1:31: String secured at depth of 2450.80 m 20:40: First communication to DOM
an IceCube-IceTop event 4 IceTop stations AMANDA deployed string
Outlook. • as aframework: high energyneutrino astronomy • the world of neutrino telescopes: current projects • recent physics results from AMANDA and Baikal • ICECUBE: status and capabilities • summary
summary • a wealth of physics results from the currently working neutrino telescopes on several topics • sensitivity reaching the level of current predictions of n productionin AGN.Some models already excluded @ 90%CL • first Km3 project (IceCube) started at the South Pole: first events seen • two projects + R&D efforts for a Km3 detector in the Mediterranean
Absorption ice bubbles dust dust detector medium: nice ice effective scattering length absorption length AMANDA depth AMANDA depth on average: optical properties: data from calibration light sources deployed along the strings and from cosmic ray muons.
sliding window events time search for neutrino flares search for neutrino flares without a-priori hypothesis on their time of occurrence search for excesses in time-sliding windows: galactic objects: 20 days extra-galactic objects: 40 days Preliminary … out of 12 Sources → no statistically significant effect observed
AMANDA: sensitive in very different energy regimes Energy range production site(s) galactic extra galactic
TRANSIENT WAVEFORM RECODER UPGRADE • Transient Waveform Recorder system • installed between the 2001 and 2004 • campaigns • Increased OM dynamic range x ~100 • Increased 1pe detection efficiency • Virtually dead-time free • Manageable trigger rate: ~150 Hz • (majority 18) • Possibility of using software trigger • Under evaluation • Physics benefits: • Improved angular resolution • Improved energy resolution • UHE/EHE physics
IceCube: time plan Up to 18 holes per season: Nov.:preparation Dec.:construction Jan.:construction Feb.:commissioning
IceCube: sensitivities Diffuse nmsensitivity Point source nmsensitivity
IceCube+AMANDA event • verification of newly deployed string • off-line synchronization of AMANDA and IceCube data
May '02 June '02 July '02 POINT SOURCE SEARCH: TIME WINDOW EXCESS “Orphan flare” (MJD 52429) Example: 1ES1959+650 Preliminary sliding search window Error bars: off-source background per 40 days
Preliminary! ... very rare - very high energy events many proposals for radio and acoustic detectors in ice, water, salt, from moon .. e.g. ice: >>km attenuation length sparse instrumentation 100-fold volume increase ... or moon, ice radio emission >100 < 10 GZK neutrinos/year
RICE AGASA Amanda, Baikal 2002 RICE GLUE 2004 2007 Anita AUGER nt Amanda,Antares, Baikal, Nestor 2012 Auger + new techn. km3