Potential Neutrino Signals from Galactic Ray Sources Alexander

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Potential Neutrino Signals from Galactic -Ray Sources Alexander Kappes, Christian Stegmann University Erlangen-Nuremberg Felix

Potential Neutrino Signals from Galactic -Ray Sources Alexander Kappes, Christian Stegmann University Erlangen-Nuremberg Felix Aharonian, Jim Hinton MPI für Kernphysik, Heidelberg Te. V Particle Astrophysics II Madison WI, August 28 – 31, 2006 • Te. V -Ray Sources as Potential Sources • From -Rays to Neutrinos • Rates in a km 3 Neutrino Telescope Alexander Kappes University Erlangen. Nuremberg Te. V Particle Astrophysics II Madison WI, Aug. 28 - 31, 2006

Introduction n Most of our galaxy surveyed by Te. V -ray detectors n Likely

Introduction n Most of our galaxy surveyed by Te. V -ray detectors n Likely all bright Galactic Te. V -ray sources identified ) neutrino source candidates Ø How to derive neutrino flux from measured -ray flux? Ø What are the event rates in neutrino telescopes? Alexander Kappes University Erlangen-Nuremberg Te. V Particle Astrophysics II Madison WI, Aug. 28 - 31, 2006 2

Galactic Te. V -Ray Sources (I) 7 Supernova Remnant (SNR) candidates n Detection of

Galactic Te. V -Ray Sources (I) 7 Supernova Remnant (SNR) candidates n Detection of resolved -ray emission from shells n RX J 1713 -3946 (HESS) RX J 1713 -3946 (H. E. S. S. ) : Multiwavelength analysis points to hadronic origin 12 Pulsar Wind Nebula (PWN) candidates n Normally interpreted as inverse Compton up-scattering of CMBR photons by HE electrons n But if significant fraction of nuclei in pulsar wind ) Neutrinos Vela X (H. E. S. S. ) Alexander Kappes University Erlangen-Nuremberg (Horns et al. , 2006, A&A, 451, L 51) Te. V Particle Astrophysics II Madison WI, Aug. 28 - 31, 2006 3

Galactic Te. V -Ray Sources (II) 3 Binary Systems n Dense radiation fields rapid

Galactic Te. V -Ray Sources (II) 3 Binary Systems n Dense radiation fields rapid cooling of Te. V electrons ) hint to hadronic origin? n Measured -ray flux weak but strong absorption ) flux “enhanced” up to a factor 100 (LS 5039) (Aharonian et al. , 2006, J. Phys. Conf. Series, 39, 408) Galactic Centre Ridge (H. E. S. S. ) LS 5039 H. E. S. S. 1 Diffuse Emission from CR Interactions Structure of Te. V emission similar to radio emission in CS lines from molecular clouds interaction of accelerated protons ) “guaranteed” Te. V neutrino source 7 Sources without good Counterpart at other Wavelengths Alexander Kappes University Erlangen-Nuremberg Te. V Particle Astrophysics II Madison WI, Aug. 28 - 31, 2006 4

Sky Map of Known Te. V -Ray Sources (Galactic coordinates) < 25% visibility* to

Sky Map of Known Te. V -Ray Sources (Galactic coordinates) < 25% visibility* to Med. detector * > 75% visibility* to Med. detector * Visibilities for E < 100 Te. V Alexander Kappes University Erlangen-Nuremberg Te. V Particle Astrophysics II Madison WI, Aug. 28 - 31, 2006 5

From -Ray to Neutrino Flux (I) Hadronic neutrino and -ray production: 0 p+p→p +X

From -Ray to Neutrino Flux (I) Hadronic neutrino and -ray production: 0 p+p→p +X p + p → p§ + X m + m e + m Pion isospin symmetry ) ( : e : : t ) ¼ ( 1 : 2 : 1 : 0 ) Parameterisation of pion and secondary particle production (SIBYLL) (Kelner et al. , astro-ph/0606058) Primary proton spectrum: ) Neutrino / spectrum: Alexander Kappes University Erlangen-Nuremberg Te. V Particle Astrophysics II Madison WI, Aug. 28 - 31, 2006 6

From -Ray to Neutrino Flux (II) n Assuming full neutrino mixing n Relation /

From -Ray to Neutrino Flux (II) n Assuming full neutrino mixing n Relation / spectrum parameters (at Earth) Norm: p = 10 Te. V p = 100 Te. V p = 1 Pe. V Index: Cut-off: Alexander Kappes University Erlangen-Nuremberg Te. V Particle Astrophysics II Madison WI, Aug. 28 - 31, 2006 7

Assumptions made for Calculations 1. No significant contributions from non-hadronic processes to signal 2.

Assumptions made for Calculations 1. No significant contributions from non-hadronic processes to signal 2. Matter density low (no significant absorption / § decay before interaction) 3. Radiation density low (no significant p interaction / absorption) 4. Magnetic field low (muons decay without significant energy loss) 5. Size of emitting region large (full neutrino mixing) 6. NN interactions produce spectra similar to pp n For all extended (H. E. S. S. ) -ray sources conditions 1. – 6. likely valid (except condition 1. in several cases) n For (point like) Binary Systems probable 2. (no significant absorption) and 5. not true Alexander Kappes University Erlangen-Nuremberg Te. V Particle Astrophysics II Madison WI, Aug. 28 - 31, 2006 8

Neutrino and -Ray Spectra for RX J 1713. 7 -3946 (SNR) measured -ray flux

Neutrino and -Ray Spectra for RX J 1713. 7 -3946 (SNR) measured -ray flux (H. E. S. S. ) mean atm. flux (Volkova, 1980, Sov. J. Nucl. Phys. , 31(6), 784) expected neutrino flux § 1 error bands include systematic errors (20% norm. , 10% index & cut-off) Alexander Kappes University Erlangen-Nuremberg Te. V Particle Astrophysics II Madison WI, Aug. 28 - 31, 2006 9

Detector Simulation (KM 3 Ne. T) Location: Mediterranean Sea Instrumented volume: 1 km 3

Detector Simulation (KM 3 Ne. T) Location: Mediterranean Sea Instrumented volume: 1 km 3 Angular resolution for muons: PSF = 0. 3 o (E > 1 Te. V) n n Event rate: comprises (full MC simulation) attenuation in Earth conversion to detection efficiency (Kuch, astro-ph/0606507) n Neutrino spectrum cut-offs at few 10 Te. V ) earth opaqueness not taken into account n Optimal search window (flat background): Alexander Kappes University Erlangen-Nuremberg Te. V Particle Astrophysics II Madison WI, Aug. 28 - 31, 2006 10

Neutrino Rates for RX J 1713. 7– 4622 in KM 3 Ne. T (1

Neutrino Rates for RX J 1713. 7– 4622 in KM 3 Ne. T (1 km 3, 5 years) Alexander Kappes University Erlangen-Nuremberg Te. V Particle Astrophysics II Madison WI, Aug. 28 - 31, 2006 11

Neutrino Events from H. E. S. S. Sources with observed cut-off KM 3 Ne.

Neutrino Events from H. E. S. S. Sources with observed cut-off KM 3 Ne. T (1 km 3, 5 years) E > 1 Te. V Type n n n n Vela X PWN 4. 6 RX J 1713. 7– 3946 8. 2 RX J 0852. 0– 4622 HESS J 1825– 137 1. 8 Crab Nebula PWN 1. 1 HESS J 1303– 631 2. 1 LS 5039* (INFC) 0. 5 NCP: No counterpart Alexander Kappes University Erlangen-Nuremberg 0. 8 E > 5 Te. V Src Bkg Ø [ o] 9 – 23 23 Src Bkg 5 – 15 SNR 1. 3 7 – 14 SNR PWN 2. 0 0. 3 7 – 15 104 1. 9 – 6. 5 21 5 – 10 9. 3 2. 2 – 5. 2 <0. 1 NCP Binary 4. 0 – 7. 6 5. 2 41 2. 6 – 6. 7 1. 1 – 2. 7 0. 3 0. 8 – 2. 3 11 0. 1 – 0. 5 <0. 1 0. 3 – 0. 7 2. 5 0. 1 – 0. 3 at other wavelengths Te. V Particle Astrophysics II Madison WI, Aug. 28 - 31, 2006 *no -ray absorption 12

Summary n Likely, strongest Galactic Te. V -ray sources discovered ) neutrino source candidates

Summary n Likely, strongest Galactic Te. V -ray sources discovered ) neutrino source candidates n Measured -ray spectra allow robust prediction of neutrino fluxes n Simple relation between parameters of -ray and spectrum found n Event rates in a 1 km 3 Mediterranean neutrino telescope (KM 3 Ne. T) Ø about 1 event per year from each of brightest sources (E > 1 Te. V) Ø about equal number of background and signal events Alexander Kappes University Erlangen-Nuremberg Te. V Particle Astrophysics II Madison WI, Aug. 28 - 31, 2006 13