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The greatest flare of a Soft Gamma Repeater

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1 The greatest flare of a Soft Gamma Repeater
On December the greatest flare from SGR was detected by many satellites: Swift, RHESSI, Konus-Wind, Coronas-F, Integral, HEND, … 100 times brighter than ever! Palmer et al. Astro-ph/

2 Подборку оригинальных статей можно найти здесь: http://xray. sai. msu
Подборку оригинальных статей можно найти здесь:

3 Magnetars in the Galaxy
4 SGRs, 8 AXPs, plus candidates, plus radio pulsars with high magnetic fields … Young objects (about 104 yrs). Probably about 10% of all NSs.

4 Alternative theory Fossil disk Mereghetti, Stella 1995
Van Paradijs et al.1995 Alpar 2001 Marsden et al. 2001 Problems ….. How to generate strong bursts?

5 Why “magnetars”? dE/dt > dErot/dt
By definition: magnetically-powered NSs P-Pdot Direct field measurements (Ibrahim et al.)

6 Known magnetars AXPs SGRs CXOU 010043.1-72 0526-66 4U 0142+61 1627-41
1 RXS J XTE J 1E AX J 1E SGRs +candidates

7 Magnetic field measurements
Direct measurement of the magnetic field of the SGR Spin-down Long periods Ibrahim et al. 2002

8 Are SGRs and AXPs relatives?
SGR-like bursts from AXPs Spectral properties Quiet periods of SGRs ( since 1983) Gavriil et al. 2002

9 Historical notes 05 March Cone experiment. Venera-11,12 (Mazets et al.) Event in LMC. SGR Fluence: about 10-3 erg/cm2 Mazets et al. 1979

10 Main types of activity of SGRs
Weak burst. L<1041 erg/s Intermed. bursts.L=1041–1043 erg/s Giant bursts. L<1045 erg/s Hyperflares. L>1046 erg/s See a review in Woods, Thompson astro-ph/

11 Common (weak) bursts from SGRS and AXPs
Typical burst from SGR , SGR and from AXP 1E observed by RXTE (from Woods, Thompson, 2004, astro-ph/ ) (from Woods, Thompson 2004)

12 Intermediate SGR bursts
Four intermediate bursts. However, the forth is sometimes considered as a giant one (from Woods, Thompson) (from Woods, Thompson 2004)

13 Giant flare from SGR 1900+14 (27 Aug 1998)
Data from Ulysses (figure from Hurley et al. 1999a) Spike 0.35 sec P=5.16 sec L> erg/s ETOTAL>1044 erg Influenced the Earth ionosphere Hurley et al. 1999

14 27 Dec 2004 giant outburst of SGR 1806-20
Spike 0.2 sec Fluence 1 erg/cm2 E(spike) erg L(spike) erg/s Long tail (400 s) P=7.65 s E(tail) erg Distance 15 kpc

15 Konus-Wind data om SGR 1806-20 27 Dec 2004 flare
Mazets et al. 2005

16 SGR giant flares vs. GRBs
Woods et al.

17 SGRs and starformation
Possibility of a SGR detection outside the Local group of galaxies Starforming galaxies are the best sites for a search <5 Mpc. M82, M83, NGC 253 About 40 Mpc. Arp 299, NGC 3256 Possible candidates in the BATSE catalogue of short GRBs (Popov, Stern 2005)

18 Theory of magnetars Thompson, Duncan ApJ 408, 194 (1993)
Entropy-driven convection in young NSs generate strong magnetic field Twist of magnetic field lines

19 Magnetars origin (a speculative discussion)
Fast rotation is necessary (Thompson, Duncan) Spin-up of a progenitor star in a binary via accretion or synchronization Coalescence About 10% of NSs (Popov, Prokhorov 2005)


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