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Radio Emission from RRAT J1819-14 at Low Frequencies. Teplykh D., Malofeev V., Logvinenko S. Neutron stars. R ns ~ 10 km M ns ~ M B ns ~ 10 12 — 10 13 G p ~ ms - s. Anomalous pulsars. Geminga Anomalous X-ray pulsars (AXPs) Soft gamma-ray repeaters(SGRs)
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Radio Emission from RRAT J1819-14 at Low Frequencies Teplykh D., Malofeev V., Logvinenko S.
Neutron stars Rns ~ 10 km Mns ~ M Bns ~ 1012 — 1013G p ~ ms - s 9-th GAMOW SUMMER SCHOOL
Anomalous pulsars • Geminga • Anomalous X-ray pulsars (AXPs) • Soft gamma-ray repeaters(SGRs) • X-ray dim isolated neutron stars (XDINSs) • Compact X-ray objects in remnant of supernova (CCO) • Transient pulsars: - Rotating radio transients (RRATs) - switch off (B1931+24) 9-th GAMOW SUMMER SCHOOL
RRATs • These sources are characterized by the emission of bursts with duration 2–30 ms. • The maximum burst flux density is 0.1– 4 Jy. • The mean interval between bursts is 4 min–3 hrs • The 10 of 11 sources have periods in the range 0.4–7 s. And the period derivative ˙P was measured for 3 pulsars. • The inferred magnetic fields are in the 1012 – 1014 G, and ages of these objects are 0.1–3 Myrs. 9-th GAMOW SUMMER SCHOOL
RRATs 9-th GAMOW SUMMER SCHOOL
Burst observational signatures J1819-1458 M.A.McLaughlin et al. Nature, 439, 817-820 (2006) The rotational properties of neutron stars • - pulsars - magnetars - XDINS - RRATs 9-th GAMOW SUMMER SCHOOL
Observations • LPA:111.5 ± 1.5 МHz, 3.3 m / cos , Aef 20 000 m2 • Receivers:96 20 kHz, 460 5 kHz t = 28.06 ms J1819-14 46 periods of pulsars were recorded during a single observation session. On the whole 33 observation sessions have been made. 9-th GAMOW SUMMER SCHOOL
Large Phased Array 9-th GAMOW SUMMER SCHOOL
J1133+16 at 111 MHz • S = 1000 mJy • Р = 1,1s • DM = 4,8 • Δt = 2,56ms • 482periods 470 chan = 111.88 MHz 10 chan = 109.59MHz 9-th GAMOW SUMMER SCHOOL
Relative flux density Pulse phase (ms) B2310+42 at 111 MHz • S = 110 mJy • Р = 0,35 s • DM = 17,3 • Δt = 5,12 ms • 375 groups 470 chan = 111.88 MHz 10 chan = 109.59MHz 9-th GAMOW SUMMER SCHOOL
J1819-14 at 111 MHz • Sum of 4 days (January 2009) • 49 pulses 9-th GAMOW SUMMER SCHOOL
1819-14 at 111 MHz • Sum of 4 days (January 2009) • 49 pulses • With compensation for DM = 196 9-th GAMOW SUMMER SCHOOL
1819-14 at 111 MHz • Sum of 7 days • (January 2009) • 93 pulses 9-th GAMOW SUMMER SCHOOL
1819-14 at 111 MHz • Sum of 7 days (February - March 2009) • 109pulses 9-th GAMOW SUMMER SCHOOL
1819-14 at 111 MHz • Sum of 7 days (February - March 2009) • 109pulses With compensation for DM = 196 9-th GAMOW SUMMER SCHOOL
Parameters of J1819-14 at 111 MHz Ratio of the total number of bursts detected to the total observation time: 1400 MHz– 2% 111MHz~5% Sp(111)17 Jy w50 70 ms Sp(1400) 0,4Jy 1,5 (111-1400 MHz) 9-th GAMOW SUMMER SCHOOL
Conclusions • There is radio emission from RRAT J1819-14 at 111MHz. • The ratio of the total number of bursts detected to the total observation time is close to the ratio at 1400 MHz. • Spectral index ~ 1.5. It is close to the mean spectral index of normal pulsars. 9-th GAMOW SUMMER SCHOOL