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Torino - 13/07/2010



HIGH ENERGY NEUTRINO TELESCOPE Tommaso Chiarusi INFN - Sezione Bologna

on behalf of the ANTARES Collaboration Friday, July 23, 2010

Physics with High Energy Cosmic νs SNR

Binary systems



Dark Matter


protons (50 Mpc)

Exotics (magnetic monopoles, nuclearites)

Galactic photons (10 Mpc) neutrons (unstables)


low energy particles Friday, July 23, 2010

Extra Galactic


Neutrino Telescopes perform indirect measurements (Markov, 1960 )

PMTs lattice Che

ren ligh kov t

transparent media

charge current interaction νμ


Upgoing μ


incoming neutrino



dense neutrino target

track reconstruction from time and position of detected Cherenkov light assuming a θCherenkov = 43˚ in water Friday, July 23, 2010

Sky coverage

ANTARES > 75% 2 25% – 75% < 25%

TeV γ-Sources galactic extragalactic

IceCube 100% 0%

Friday, July 23, 2010

The ANTARES Collaboration

ITEP, Moscow  University of Moscow 

IFIC,Valencia  UPV, Valencia,  TUC, Barcelona 

NIKHEF, Amsterdam KVI Groningen  NIOZ Texel  

CPPM, Marseille  DSM/IRFU/CEA, Saclay  APC Paris  IPHC (IReS), Strasbourg  Univ. de H.-A., Mulhouse  Clermont-Ferrand  IFREMER, Toulon/Brest  C.O.M. Marseille  LAM, Marseille  GeoAzur Villefranche 

Tommaso Chiarusi Friday, July 23, 2010

University/INFN of Bari  University/INFN of Bologna  University/INFN of Catania  LNS – Catania  University/INFN of Pisa  University/INFN of Rome  University/INFN of Genova 

University of Erlangen  Reimes Sternwarte Bamberg. 

ISS, Bucarest

PCC 2010 - Torino 13/07/2010


Toulon La Seyne sur Mer

Main cable (45km)

Shore station

Friday, July 23, 2010

•12 lines of 75 PMTs •25 storeys/line •3 PMTs/storey •885 active PMTs

Instrumented volume 0.05 km3 ➠ high PMT density so to have a good angular resolution and optimizing the effective area Tommaso Chiarusi Friday, July 23, 2010

PCC 2010 - Torino 13/07/2010

Expected Performance (full detector) Neutrino effective area

Angular resolution

•For Eν<10 PeV, Aeff grows with energy due to the increase of σν and the muon range. •For Eν>10 PeV the Earth becomes opaque to neutrinos.

•For Eν < 10 TeV, the angular resolution is dominated by the ν-μ angle. •For Eν > 10 TeV, the resolution is limited by track reconstruction errors.

Ndet=Aeff × Time × Flux


A 0.3 deg angular resolution would imply a time precision better than 5 ns and OM position known to better than 2 m ANTARES actual time and spatial precisions: ~ 1.8 ns (= 1.3 ns TTS + 0.5 ns time calib.) on a 10” PMT and ~ 0.1 m for each OM!! Friday, July 23, 2010

ANTARES deployment

Friday, July 23, 2010

Living under the sea: the uncorrelated single photon spurious signals Sea science studies

Bursts in the rate from bioluminescence

baseline (40K + biolumin.)


decays (constant)

Bioluminescence (occasional)

40 kHz/PMT(10”, 0.5 p.e. thld) up to some MHz/PMT(10”, 0.5 p.e. thld) +

No “beam crossing” reference such as for experiments at Colliders +

complex DAQ structures in extreme conditions (mandatory: minimal underwater maintaining) ➠ ALL DATA TO SHORE approach (up to 15 Gbps total) Friday, July 23, 2010


Acoustic Positioning

Example for Sea current v= 25 cm/s rmax = 22m

• Acoustic system • 1 emitter (+ receiver) at each line socket • 5 receivers along each line • Compass and Accelerometer • 1 Compass at each storey • 1 Accelerometer at each storey • Measure every 2 min • Acoustics: distance sockets - receivers • Compass: Heading • Accelerometer: tilt Tommaso Chiarusi Friday, July 23, 2010

PCC 2010 - Torino 13/07/2010


mostly coherent movement of lines

Atmospheric muons and neutrinos p 5-line data (May-Dec 2007) + 9-12-line data (2008)

µ νµ

cosmic rays


341 days detector live time 1062 neutrino candidates

cosmic νµ

νµ µ


Preliminary good agreement with Monte-Carlo expectation: upward-going: atmospheric neutrinos: 916 (30% syst. error) atmospheric muons:

Zenith angle Friday, July 23, 2010

40 (50% syst. Error)

Muon Depth Intensity Relation ANTARES data with 5 lines

Tommaso Chiarusi Friday, July 23, 2010

PCC 2010 - Torino 13/07/2010

Scrambled ANTARES Sky map of 1000 neutrinos

Galactic coordinate System

Tommaso Chiarusi Friday, July 23, 2010

Earth coordinate System

PCC 2010 - Torino 13/07/2010

Point source sensitivity

Point source search with 5-lines data (2007) is close to be finalized.

pre lim


Tommaso Chiarusi Friday, July 23, 2010


In the next weeks the ANTARES Collaboration will publish the relative upper limits

PCC 2010 - Torino 13/07/2010

Dark matter searches

5-line data 2007 (68 days) 68 days detector live time


Competitive with direct detection for SD cross section

Neutralino mass (GeV) Friday, July 23, 2010

Diffuse Flux: energy estimator

R =

number of PMTs with prompt and late photons number of all PMTs contributing to the event


good slope for energy resolution


Friday, July 23, 2010


Diffuse Flux: unblindig the data E2 \test = 10-7 GeV cm-2 s-1 sr-1

Atms i, no R cut Atms i, R*1.31 Signal i, no R cut Signal i, R*1.31



νprompt (Bartol+RQPM)














log (Ei/GeV) 10

R =

Tommaso Chiarusi Friday, July 23, 2010

number of PMTs with prompt and late photons number of all PMTs contributing to the event

PCC 2010 - Torino 13/07/2010

Diffuse Flux: upper limit with 2007-2009 data

pre lim



• MACRO: Astropart.Phys. 19:1-13,2003. • BAIKAL, Astronomy Letters, 2009, Vol. 35, No. 10, pp. 651–662. • AMANDA-II (807 d) Phys.Rev.D76:042008,2007 • IceCube: Astrop. Phys. 20 (2004) 507 • WB= Waxman & Bahcall, PRD59 (1999) • MPR98, PRD 63 (2001) • SDSS91: Phys. Rev. Lett. 66(91)2697

Tommaso Chiarusi Friday, July 23, 2010

PCC 2010 - Torino 13/07/2010

Ongoing combined searches • Receive GRB alerts from Satellites (Fermi, Swift...) search for coincident neutrinos within time window (~100 seconds)

• Send neutrino cluster alert for optical follow-up Trigger: multiple / HE single neutrino event; Reconstruction “on-line” (<10ms)

Alert message to Tarot Telescope in La Silla (Chile) Tarot takes 6 images of 3 minutes immediately and after 1, 3, 9 and 27 days sending alerts to the ROTSE system (4 telescopes) since 3 months

• Correlation with AUGER source distribution investigate directional correlation of neutrinos and UHE particles

• Correlation with VIRGO-LIGO signals investigate correlation of neutrinos and gravitational waves

Tommaso Chiarusi Friday, July 23, 2010

PCC 2010 - Torino 13/07/2010

Conclsions ANTARES • is continuously taking data • has a broad physics program • determined the most sensitive upper limit on diffuse flux • complements the sky coverage of IceCube • paves the way for KM3NeT Tommaso Chiarusi Friday, July 23, 2010

PCC 2010 - Torino 13/07/2010

THANK YOU! Essential Bibliography 1. T. Chiarusi and M. Spurio, 2010, High-Energy Astrophysics with Neutrino Telescope, European Physics Journal C 65, nn. 3-4, 649 2. J. A. Aguilar et al. Transmission of light in deep sea water at the site of the Antares neutrino telescope. Astropart. Phys. 23 (2005) 131-155. 3. P. Amram et al. Sedimentation and Fouling of Optical Surfaces at the ANTARES Site. Astropart Phys. 19 (2003) 253-267. 4. P. Amram et al. The ANTARES optical module. Nucl. Instr. Meth. A484 (2002) 369. 5. M. Ageron et al. Studies of a full scale mechanical prototype line for the ANTARES neutrino telescope and tests of a prototype instrument for deep-sea acoustic measurements. Nucl. Instrum. Meth. A581 (2007) 695-708. 6. J. A. Aguilar, The Data Acquisition System of the ANTARES neutrino telescope, Nucl. Instrum. Meth. A 570 (2007) 107-116 7. A.Margiotta(ANTARESColl.), Systematic uncertainties in MonteCarlo simulations of the atmospheric muon flux in the 5-line ANTARES detector. Nucl. Instrum. Meth. A602 (2009) 76. arXiv:0809.0268 [astro-ph]. 8. G. Carminati, A. Margiotta, M. Spurio. MUons from Parametric formulas: A fast Generator of atmospheric Îź-bundles for neutrino telescopes (MUPAGE). Nucl. Instr. Methods A602 (2009) 95 9. J.A. Aguilar et al, Zenith distribution and flux of atmospheric muons measured with the 5-line ANTARES detector, in press on Astropart. Physics (ASTROPARTPHYS-D-10-00029R2)

Friday, July 23, 2010


Friday, July 23, 2010

Observation of induced electromagnetic showers from muon tracks The light from EM shower is produced in â&#x20AC;&#x153;one pointâ&#x20AC;? on the muon path and it arrives delayed at PMT


Friday, July 23, 2010

ANGULAR RESOLUTION angular resolution = difference between reconstructed and MC generated angles vs. neutrino energy

µrec− µgener. µrec−νgener. dominated   by  kinema+cs



dominated by  reconstruc+on

Friday, July 23, 2010

angular resolu+on   <  0.2°  above   ≈ 10  TeV   limited  tracking  accuracy    due  to  <me  resolu<on:   Light  scaAering  σ  ~  1.0  ns   TTS  in  PMT            σ  ~  1.3  ns   <me  calibra<on    σ  <  0.5  ns   OM  posi<on            σ  <  10  cm   25        (↔  σ  <  0.5  ns)

THE ANTARES DETECTOR POSITIONING SYSTEM • REAL TIME  POSITIONING   Acous<c  posi<oning  system  +  set  of  <ltmeters  and  compasses. • Transceivers  (RxTx)  on  the  boAom  of  the  lines,  4  autonomous  transponders  around  the   apparatus. • 5  hydrophones  (Rx)  per  line  at  specific  heights. • Tiltmeter  and  compass  per  storey,  sound  velocimeters  (various  depths). RECONSTRUCTION  OF  THE  LINE  SHAPE   GLOBAL  χ2  FIT  TO  LINE  SHAPE   MODEL  (BEHAVIOUR  OF  LINE:  SEA  CURRENT)  

Hydrophone posi+on  rela+ve  to  line  base  loca+on  (20  days)


Acoustic transceiver

Friday, July 23, 2010

Acoustic transceiver

Resolu+on be3er  than  10  cm

TIME CALIBRATION Time  difference  between  the  LED  OB  and  an  OM 3  OMs

σ = 0.4  ns


Op+cal LED  beacon

-­‐ Electronics  +  calibra0on  

σ ~ 0.5  ns

-­‐ TTS  in  photomul0pliers    

σ ~ 1.3  ns

-­‐ Light  sca?ering  +  dispersion  in  sea  water  

σ ~  1.5  ns  at  40  m  

Angular resolu+on        0.3o  (for  Eν  >  10  TeV  ) Including  the  acous+c  posi+on  resolu+on  and  the  ν-­‐µ  angle Friday, July 23, 2010





The biggest  challenge  is  to  determine   the  separate  contribu<on  of  absorp+on  and  sca3ering Friday, July 23, 2010

IN SITU CALIBRATION WITH 40K Integral under peak  =  rate  of   correlated   coincidences


Gaussian peak  on   coincidence  plot

Cherenkov γ

e-­‐ (β  decay) 40K

Peak offset 29


No dependence  on   bioluminescent  ac<vity  has   been  observed

Friday, July 23, 2010

Cross check  of   <me  calibra<on  

High precision  (~5%)   monitoring  of  OM   efficiencies

Physics with High Energy Cosmic νs 

Understanding production mechanism (‘cosmic accelerators’) of SNR

HE cosmic rays 

Study very energetic objects: 

galactic: SN remnants, microquasars..

extragalactic: GRB, AGN,…;

Search for Dark matter (wimps)

Exotic (magnetic monopoles, nuclearites)

Binary systems


Dark Matter


Exotics (magnetic monopoles, nuclearites) Friday, July 23, 2010


Latest results of the ANTARES high-energy neutrino telescope

t c a w r t e i s v b e A rr o f e y b l l l n i o w e d i ls t s u i c h t

The ANTARES high-energy neutrino telescope, fully functional since May 2008, is based on the detection of Cherenkov light produced in sea water by neutrinoinduced muons as well as electromagnetic or hadronic showers. It consists of a three-dimensional array of 885 photomultipliers distributed over 12 lines and installed at a depth of 2500 m in the Mediterranean Sea, 40 km off the French coast. The main goal of the experiment is the search for highenergy neutrinos from astrophysical sources such as AGNs, GRBs and SGRs or possibly from WIMP annihilation in the Sun or in the Galactic Halo. The telescope is sensitive to neutrinos with energy greater than few hundred GeV, with an effective area for upward muon detection which reaches 0.05 km2 at the highest energies. In this talk we review the current status of the detector; we give an overview on the atmospheric muon and neutrino analyses and present the first searches for point-like neutrino sources and diffuse flux of VHE neutrinos using data from Dec. 2007 to Dec. 2009.

Friday, July 23, 2010

Presentation PCC 2010  

Antares a PCC 2010, Torino

Presentation PCC 2010  

Antares a PCC 2010, Torino