THE COSMIC RAYS

THE COSMIC RAYS

Wolfgang Kundt

Argelander Institute of Bonn University

Vulcano, 29 May 2008

COSMIC-RAY BOOSTING

• Not via multi-step accelerations, (in situ, Fermi 1, 2 , shock acceleration): Journal of Astrophysics and Astronomy 142, 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.

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.

THE GAMMA-RAY BURSTS

Wolfgang Kundt,

Vulcano, 29 May 2008

GAMMA-RAY-BURST PROPERTIES

Wolfgang Kundt, 27. September 2006

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



Burst Spectra

log( S)

log(h/MeV)1



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].

4S

10S38L



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 ?!



CONSTRAINTS (3)

• 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).

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.

References

• Aharonian, F., Ozernoy, L., 1979: Astron. Tzirk 1072, 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: Nature 444, 1044-1046• Grupe et al, 2007: Ap. J. 662, 443-458• Hjorth, J., et al (20 authors), 2006: The Messenger 126, 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: Nature 271, 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 & A 134, 301-305

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.

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.



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THE COSMIC RAYS