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THE COSMIC RAYS

THE COSMIC RAYS. Wolfgang Kundt Argelander Institute of Bonn University Vulcano, 29 May 2008. COSMIC-RAY BOOSTING.

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THE COSMIC RAYS

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  1. THE COSMIC RAYS Wolfgang Kundt Argelander Institute of Bonn University Vulcano, 29 May 2008

  2. COSMIC-RAY BOOSTING • Not via multi-step accelerations, (in situ, Fermi 1, 2 , shock acceleration): Journal of Astrophysics and Astronomy142, 150-156 (1984). Note also: their highest energies would require excessive Bs. • Rather by single-step sweeping via corotating magnetic fields, (eE x B-force)  see modified Hillas plot  preferentially by magnetars, but also by the (coronas of the) central disks of active galaxies.

  3. The SPECTRUM of the COSMIC RAYS • peaks in power near the ionic rest energy, (a few GeV), • extends in particle energy up towards 1020.5 eV, • wants Galactic neutron stars as boosters, because of: • W = e # (E +  ×B)·dx = 1021eV ( ×B)12(x)6.5 , • i.e. via a single fall through a strong potential, near the inner edge of a n*´s accretion disk, which will indent deeply into its corotating magnetosphere. • Note that ions above 1018eV are not contained by the galaxy´s magnetic fields (for some 107 yr)  as are the lower-energy ones  hence abund vastly more near their sources. They require robust engines.

  4. THE GAMMA-RAY BURSTS Wolfgang Kundt, Vulcano, 29 May 2008

  5. GAMMA-RAY-BURST PROPERTIES HISTORY • FIRST DETECTION: 2 July 1967 • FIRST CONFERENCE: X-mas 1974 • FIRST REPEATER: 5 March 1979 • CONSENSUS (1980s): Galactic n** • PRESENT MODELS: Fusing binary neutron stars or black holes at cosmic • distances, without further detail • PREFERRED MODEL: as during 80s Wolfgang Kundt, 27. September 2006

  6. GAMMA-RAY-BURST PROPERTIES Burst Spectra log( S) 1 log(h/MeV) Wolfgang Kundt, 27. September 2006

  7. GAMMA-RAY-BURST PROPERTIES CONSTRAINTS (1) • No Pair Formation at Source: d < kpc / • Neutron-star Energetics: d < kpc  • Afterglow Brightness (at low ): d < 0.3 kpc / • Modest Proper Motion of SGR (& radio lobe): d  30pc • Tolerable Luminosity of SGR (k-Eddington): d  30pc • Resolved X-ray Afterglow (growing concentric rings)!? • No Long-Distance travel signatures!? [Mitrofanov, 96] •  Pre- and Post-cursors (offset by  hour)!? [X.Y.Wang & P.Mészáros (2007) discuss delays of 10s and 102s]. Wolfgang Kundt, 27. September 2006

  8. GAMMA-RAY-BURST PROPERTIES CONSTRAINTS (2) • Accreting Galactic dead-pulsar population should be detected (10-17 M/yr n*) ! • Thin-shell energy distribution: <dmax/dmin> = 2 ! • No-Host dilemma: Brad Schaefer et al, [97, 99] • Brightness Excess at high z ( 7): B. Schaefer [07] • Hardness Excess ( 1013 eV) ! • Duration Excess (hour) ! • Afterglow Brightnesses are z-independent !? • L(afterglow)  L(prompt): no beaming ?! Wolfgang Kundt, 27. September 2006

  9. CONSTRAINTS (3) GAMMA-RAY-BURST PROPERTIES • X-ray Afterglows don´t evolve (increasing ionization!) • X-ray Afterglows can fade slowly ( 125 d) ! • All host galaxies – when , and not fake – are peculiar, as a class ! [B.Cobb & Ch.Bailyn (2007), also GRB 070125]. • No Orphan Afterglows have been detected ! • Cavallo-Fabian-Rees limit on L/t • L(after)/L(prompt) ≅ 1 for GRB 060729 ! • The Mg II absorbers are 4-times overabundant (w.r.t. those of quasars), and time-variable (hours). • GRB 070201 has not been seen at g-waves (by LIGO). Wolfgang Kundt, 27. September 2006

  10. CONSTRAINTS (4) • Superluminally expanding radio afterglows, like for GRB 030329 [(4±1)c], and mystery spots [19c], would require pre-existing jet channels [G. Taylor et al (2005)]; similarly for SGR 1806-20 [B. Gaensler (2006)]. • GRB 080319B was the brightest known optical point source in the Universe, aleady 20 sec after outburst! • X-ray afterglow lightcurves show strong flares (<102), between minutes and days after outburst, as well as steep falls! [Chincarini et al (2007); also: Troia et al (2007)]. • Bright optical afterglow follows -ray intensity (GRB 080319B) within a few sec, between 13s and 60s after onset; similarly for GRB 990123.

  11. References • Aharonian, F., Ozernoy, L., 1979: Astron. Tzirk1072, 1 • Chincarini, G., et al (14 authors), 2006, The Messenger 123, 54-58 • Colgate, S.A., Petschek, A.G., 1981, Ap. J.248, 771-782 • Gehrels, N., et al (20 authors), 2006: Nature444, 1044-1046 • Grupe et al, 2007: Ap. J.662, 443-458 • Hjorth, J., et al (20 authors), 2006: The Messenger126, 16-18 • Kundt, W., 2005: Astrophysics, A New Approach • Kundt, W., Chang, H.-K., 1993: Astroph. Sp. Sci. 200, L151-L163 • Marsden, D., Rothschild, R.E., Lingenfelter, R.E., 1999: Ap. J.520, L107-110 • Schaefer, B.E., 1999: Ap.J.511, L79-L83 • Schaefer, B., 2007: Am.Astr.Soc.Meeting, 12 highest-z GRBs (52) too bright • Schmidt, W., 1978: Nature271, 525-527 • Song, Fu-Gao, Jan. 2008: astro-ph/0801.0780 • Sudilovsky, V., et al (6 authors), 2007: Ap. J. 669, 741-748 • Taylor,G.B., Frail,D.A., Berger,E., Kulkarni,S.R., 2004: Ap. J.609, L1-L4 • Vietri, M., Stella, L., Israel, G., 2007: astro-ph/0702598v1 • Zdziarski, A., 1984: A & A134, 301-305

  12. PREFERRED MODEL (1) • Most GRBs come from (n*s at distances) d  (0.1 , 0.2) kpc. • The nearest bursts, the SGRs, have distances d  10 pc. • The GRBs are emitted by throttled pulsars, whose magnetosphere is deeply indented by a low-mass accretion disk assembled from its CSM. These disks tend to be  the Milky Way. Their (anisotropic) emissions – by ricocheting, accreting `blades´ – peak near their disk plane, strengthening an isotropic appearance of the bursts in the sky. • The afterglows are light echos, or transient reflection nebulae. • Centrifugally ejected ion clouds escape transluminally, and show up redshifted in absorption against the burst impact´s light, mainly their receding sector. In extreme cases of large mass ejections (at small speeds), the afterglows can look like SN shells, by acting as photon bags.

  13. PREFERRED MODEL (2) • The short GRBs, of peak duration < 2 sec, result by accretion of a single blob (blade), of size of a terrestrial mountain; they are modul- ated by the throttled pulsar´s spin (of period 5s to 10s), and soften and tail off within some 102 sec. They form basic events, [Piran (2005)]. • The long GRBs are superpositions of short GRBs, cf. the July 1994 accretion by Jupiter of comet Shoemaker-Levy. • Part of the (hot) accreted blob rises to a large scale-height, and gets centrifugally ejected, as a transluminal, baryonic burst. • Occasionally, accretion onto a throttled pulsar can trigger additional high-energy activities, of much longer duration (than 103 sec). • SN-like afterglow lightcurves result because of SN-like ejections.

  14. GAMMA-RAY-BURST PROPERTIES Long Short Wolfgang Kundt, 27. September 2006

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