1 / 16

Rezo Shanidze

KM3NeT sensitivity to neutrino bursts from galactic supernovae. Rezo Shanidze. VLVnT08 - Toulon, Var, France 22-24 April 2008. Introduction. Is a n -burst from a core collapse of a massive star (Supernova type-II) in Galaxy detectable with KM3NeT ?

annhiggins
Download Presentation

Rezo Shanidze

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. KM3NeT sensitivity to neutrino bursts from galactic supernovae Rezo Shanidze VLVnT08 - Toulon, Var, France 22-24 April 2008

  2. Introduction • Is a n-burst from a core collapse of a massive star (Supernova type-II) in Galaxy detectable with KM3NeT ? • Layout of the talk: - Supernova neutrinos - The SNEWS project - SN-n in the neutrino telescopes - Studies for ANTARES - Estimations for KM3NeT - Summary and outlook ? The “Grand unified” neutrino spectrum from ASPERA Roadmap (phase I). Status and Perspectives of Astropartile Physics in Europe www.aspera-eu.org R.Shanidze, VLVnT08 - Toulon, var, France, 22-34 April, 2008

  3. Neutrinos from the core collapse • A. Burrows, • Annu. Rev. Nucl. Part. Sci, 40 (1990), 181 The neutrino luminosity (Ln) vs. time. Calculations of Myra&Burrows for 13 Mʘ progenitor star and 1.17 Mʘ iron core The time integrated neutrino number spectra vs. n-energy R.Shanidze, VLVnT08 - Toulon, var, France, 22-34 April, 2008

  4. SN neutrino interactions ne+p gn+ e+ (1) ne + 37Cl g37Ar + e- (4) ne + e-gne + e- (2) ne + 16O g16F + e- (5) nm,t+e-g nm,t+e- (3) ne + 16O g16N + e+(6) nl + 16O g16O* + nl(7) • The neutrino interaction cross-sections on the different targets vs. energy. • From A.Burrows, D.Klein, R.Gandhi, PR D45(1992), 3361 R.Shanidze, VLVnT08 - Toulon, var, France, 22-34 April, 2008

  5. Neutrinos from SN1987A K-II: K. Hirata et al, PRL 58(1987), 1490 IMB: R. M. Bionta el al, PRL 58(1987), 1494 Baksan: E.N. Alexeyev et al. PL B205(1988), 209 The neutrinos from SN1987A detected by Kamiokande-II, IMB and Baksan detectors. 23 Feb. 1987, 7:35:35 UT 18 h prior to the first optical sighting Exp. n-Events DT(sec.) E (MeV) K-II: 12 13 7.5 - 36 IMB: 8 6 20 - 40 Baksan: 5 9 12 - 23 R.Shanidze, VLVnT08 - Toulon, var, France, 22-34 April, 2008

  6. The SN Early Warning System http://snews.bnl.gov/ Expected SN rate in our Galaxy ~1-3 / century Important not to miss ! The goal of SNEWS is to provide the astronomical community with a prompt alert of the occurrence of a Galactic core collapse event. Technical description of the SNEWS: New J. Phys. 6(2004),114 [ astrpo-ph/0406214] The SN prompt alert g International network of n-experiments: Super-K, LVD, IceCube/AMANDA ( SNO until 2006) False alert rate of SNEWS < 1 century: Minimum acceptable level for 10s coincidence: 2 experiments, each with a false alarm rate ≤1 per week. R.Shanidze, VLVnT08 - Toulon, var, France, 22-34 April, 2008

  7. SN1987A signal in K-II The SN neutrinos in a neutrino telescope • First suggested for AMANDA: • F. Halzen, J. E. Jacobsen and E. Zas • Phys. Rev. D49(1994), 1758, • Ultratransparent Antarctic ice • as a supernova detector Predicted excess of N(p.e.) in a with NOM (10s): 11 - events in Kamiokande-II 2.14kton – target mass of Kamiokande-II 52 kpc - distance to SN1987A • J. Ahrens et al., (AMANDA Collaboaration), • Astropart. Phys. 16(2002), 345 • 302 OMs, 215 day (1997-1998) R.Shanidze, VLVnT08 - Toulon, var, France, 22-34 April, 2008

  8. AMANDA-II AMANDA-B10 IceCube 30 kpc IceCube sensitivity to the Galactic supernovae IceCube is sensitive to SN1987A type neutrino burst signal from a distance dSN < 30 kpc. (For 6s signal) Number of the fake SN alerts in IceCube < 15 y-1 The distribution of progenitor stars in the Milky Way, located within a distance r(kpc) from the Earth. ( Astropart. Phys.,16(2002), 345) R.Shanidze, VLVnT08 - Toulon, var, France, 22-34 April, 2008

  9. Supernova neutrinos in the undersea telescopes The main difference from other water/ice Cherenkov detectors: a complex sea environment - 40K, bioluminescence, currents, … ANTARES data: From Dec.2007 data taking with 10 lines (from 12). Constant monitoring of the deep sea environment. 3D virtual picture F.Montanet, CNRS/IN2P3 for Antares • The sources of “environmental photons” in ANTARES: • Steady, isotropic radiation from radioactive potassium 40K :~ 350 photons/cm2s. • Continuous bioluminescence ( from bacteria) • Localized bioluminescence bursts ( connected to the macroscopic organisms) R.Shanidze, VLVnT08 - Toulon, var, France, 22-34 April, 2008

  10. ANTARES environmental data Constant on-line monitoring of the sea environment is ANTARES: The values of current mean speed/ direction recorded in ANTARES. R.Shanidze, VLVnT08 - Toulon, var, France, 22-34 April, 2008

  11. Studies for the ANTARES telescope [1]S. Basa, ANTARES-PHYS-1998-03 [2]Y. Becherini, G. Ramadori, M. Spurio, ANTARES-PHYS-2002-002 • - GEANT 3 simulation of the cherenkov photons produced from positrons • in the inverse beta reaction from of the electron anti-n. • ANTARES configuration [2]: 900 OM/PMTs (10 line detector) • Different signals studied : 1, 2, 3 p.e hit rates, coincidence rates (c2) • SN (SN1987A type) • at D=10 kpc (GC) • Maximal sensitivity for • 1 p.e. signals • Above 3 s limit for • Dt< 1 s • negligible signal from • electron neutrinos 25 ms 100ms 10 s 1, 2, 3 - p.e. signal; 4,5 – C2 coincidence R.Shanidze, VLVnT08 - Toulon, var, France, 22-34 April, 2008

  12. The KM3NeT configuration For SN study: KM3NeT is a collection of OMs/PMTs. CDR options: 1) Standard: 10” Hamamatsu R7081 2) Directional 10” OM 3) Small: 3” Photonis XP53X2 ( for Multi-PMT (Flykt) OM ) 4) X-HPD based OM 4 3 2 The “reference detector”: 8325 Multi-PMT OM (15 x 15 x 37) R.Shanidze, VLVnT08 - Toulon, var, France, 22-34 April, 2008

  13. Possible SN signal in the KM3NeT telescope The KM3NeT detector performance evaluated for the reference detector. ANTARES g KM3NeT 5 s significance: < 1 event/ week 900 OM (10” PMT) 8325 OM (21 x 3” PMT) • Constant background from the K40 decays: • ~ 100 Hz cm-2/PMT : • ~ 40 kHz for 10” PMT/OM (ANTARES) • ~ 80 kHzfor Flykt-OM (21x0.09 = 1,8OMANTARES) KM3NeT 0.025 S=N/s ratio 0.050 0.5 • The S=N/s ratio for ANTARES and • KM3NeT vs time. in sec. • KM3NeT data is obtained by rescaling • the number of OMs: • 1) Same type of OM (▪) • 2) “Flykt-OM” () 0.1 10.0 20.0 ANTARES Time [ sec.] R.Shanidze, VLVnT08 - Toulon, var, France, 22-34 April, 2008

  14. Possible improvements • Time evolution of the SN signal (N/s ratio): • For example 2 trigger windows Dt1 and Dt2 and a correlation from the • time evolution of the SN signal can significantly increase the sensitivity • of KM3NeT to the n-bursts from the Galactic supernovae. Dt1 Dt2 OM with new PMTs ~ 1.7 x QE R.Shanidze, VLVnT08 - Toulon, var, France, 22-34 April, 2008

  15. ANTRES/ KM3NeT data model All data to shore concept: • Fast front-end electronics • High bandwidth • Software Trigger M. de Jong, KM3NeT CDR meeting. • “Supernova online trigger” • can be implemented on a • “on-shore” data, which • could run in parallel to • other triggers: • m - trigger • GC - trigger • GRB - trigger GRB trigger: All ANTARES hits (L0) detected in 120s are stored on a disk for GCN alert (~ 23 GB/trigger ) Same date can be used for “SN trigger” study in ANTARES. R.Shanidze, VLVnT08 - Toulon, var, France, 22-34 April, 2008

  16. Summary and Outlook • First study indicates, that the KM3NeT neutrino telescope can • detect a supernova neutrino burst as a significant excess of OM • rates ( > 5s) in a short time interval (~10 s) , for a SN1987A type • supernova explosion at a distance < 10 kpc. • Constant monitoring of the sea environment will be necessary to keep • a “false supernova trigger” rate below a level acceptable by the • SNEWS network ( ≤ 1/week). • After the selection of KM3NeT neutrino telescope configuration, • the optical modules and the site, sensitivity to the neutrino bursts • from the supernovae can be studied with dedicated MC (GEANT4) • simulations. • The “ supernova neutrino trigger” can be designed and tested for • the ANTARES neutrino telescope, with an aim of providing the rate • below 1 trigger/week. R.Shanidze, VLVnT08 - Toulon, var, France, 22-34 April, 2008

More Related