Variability of cosmic Gamma-Ray Burst (II)

A. Pozanenko*, V. Loznikov* , R. Preece#

*Space Research Institute (IKI)

#Dept. of Physics, Univ. of Alabama in Huntsville

• Aperiodic variability (I)

Coherent variability (II)

Short duration GRB connection with SGR?

• 1982: Mazets, E. P., et al., Ap&SS, 84, 173• 1982 …….. -- ……… 2004• 2004: Boggs, S. et al. SGR1806-20, RHESSI

observations of the 041227 giant flare, GCN Circ. No. 2936

Soft Gamma-ray Repeaters

• Sporadic activity in soft gamma-rays

• 4 SGRs are known (SGR 0526-66, SGR 1900+14, SGR 1627-41, SGR 1806-20)

• Giant Flashes followed long pulsating tail (period 5 – 8 seconds)

• Magnetars = Neutron star with intense magnetic field (> 1014 G)

• Close to the Earth (6-55 Kpc)

Dec.27 2004 Giant Flash of SGR1806-20

• RHESSI, INTEGRAL, Konus-Wind, Swift, Geotail, Helicon-Coronas-F …

Dec.27 2004 Giant Flash of SGR1806-20

RHESSI, K.Hurley et al.

Dec.27 2004 GF of SGR1806-20

Konus-Wind, E.Mazets, et al. Swift, D. Palmer, at al

Dec.27 2004 Giant Flash of SGR1806-20

Short duration GRB

• Duration of T90 less than 2 seconds

• No counterparts

• A separate class of GRBs

• Possible Distant (< 30 Mpc) SGR?

Short duration GRB …

Short GRB time profilesin different energy bands…

Before start:

• Can be Giant Flash from SGR detected from distance about 30 Mpc?

• Is it enough SGRs within 30 Mpc?

• Can be detected Pulsating Tail of distant SGR?

Before start:

• Can be Giant Flash from SGR detected from distance about 30 Mpc? YES

• Is it enough SGRs within 30 Mpc? YES

Can be detected Pulsating Tail of distant SGR???

• The tail energy is the same for all Giant Flashes from SGRs registered

• The ratio of Main Spike of Giant Flashes to the amplitude of pulsation in the tail is varying between 40 and 600

• The amplitude of pulsation depends on geometry, and does not depend on Main Spike

For bright short GRB of BATSE the tail may be detected!

Burst Choice

BATSE:

• Short GRBs (T90 < 2 s)

• Bright GRBs (F64 > 25 phot/cm^2/s)

• 64 ms data • Chan1 ( ~ 25 – 50 keV)• Chan2 ( ~ 50 – 100 keV)• Chan3 ( ~ 100 – 300 keV)• Chan4 ( > 300 keV)

BATSE GRB time profile:Resolution, data types and coverage

To – trigger timeBATSE:DISCSC+PREB – 64ms, To-2.048, To+ ~150 s

BATSE Short GRB F64 > 25 phot/cm^2/s

Id Name comments

0298 910609

0444 910626

2514 930905

3152 94090

3412 950211

3736 950805

6293 970704-

6668 980330 telemetry errors

BATSE 2514 (930905)time profile

Time

0 50 100 150 200

Cou

nts

per0.

064s

Time

0 50 100 150 200

Cou

nts

per0.

064s

102

103

104

BATSE 2514 (930905)Power spectrum, Periodogram

0.01 0.1 1 100

5

10

15

20

#3

0.1 0.2 0.3 0.40

1

2

3

4

5

#3

Pow

erR

educ

ed

2

Frequency, Hz

BATSE 2514 (930905)Phase profile in 100-300 keV

P = 6.425 s

Phase

0.0 0.5 1.0 1.5 2.0 2.5

Cou

nts

perbi

n

57500

58000

58500

59000

59500

60000

Anomalous X-ray Pulsars(V. M. Kaspi., F. P. Gavriil, 2004), HXMB

BATSE Short GRB F64 > 25 phot/cm^2/s

Id Name Possible period

0298 910609 -

0444 910626 1.66 +- 0.05 ?

2514 930905 6.425 +- 0.160

3152 94090 4.00 +- 0.11 ?

3412 950211 6.79 +- 0.17 ?

3736 950805 -

6293 970704- -

6668 980330 Data corrupted in telemetry

Conclusions

• First direct connection of SGR and Short GRB

• Bright galaxy with intensive star formation should be searched within error-box of GRB with (pulsating) tail

• One can estimate distances to Short GRBs which manifest the pulsating tail

• Swift will be able to detect pulsating tale of Short GRB >~ three times more efficiently