1. Long-term monitoring of RRAT J1819-1458 HU HuiDong huhd@uao.ac.cn Urumqi Observatory, NAOC July 27, 2009 Rotating Radio Transients Observation

2. Introduction Rotating Radio Transients (RRATs) Rotating Radio Transients (RRATs) 11 discovered and published on Nature (M. A. McLaughlin et al. 2006) (M. A. McLaughlin et al. 2006)  Characters of the 11 RRATs Bursts duration between 2 and 30 ms Bursts duration between 2 and 30 ms Average time intervals between bursts range from 4 minutes to 3 hours Average time intervals between bursts range from 4 minutes to 3 hours Periodicities, 0.4-7s Periodicities, 0.4-7s Detectible flux duration <1s/d Detectible flux duration <1s/d Brightest radio sources after the giant pulses from the Crab pulsar and the pulsar B1937+21. Brightest radio sources after the giant pulses from the Crab pulsar and the pulsar B1937+21.  The number of RRATs may exceed that of regular pulsars

3. NamePPdotDMRaDec Burst Rate Survey s10 -15 s/spc/cm^3hh:mm:ss.sdd:mm:ss.s 1/h J0054+661.39 1500:54+66240GBT350 J0557-15 4305:57-14:203.43PH J0755-44 11507:55-44:285.14PH J0848-435.97 29308:48-43:161.42PM1 J1047-581.23 6910:47-58:416.86PM2 J1131-57 13011:31-57:111.71*PM2 J1317-57592.6412.614513:17:46.357:59:30.24.5PM1 J1328-58 21313:28-58:541.71*PM2 J1423-56 3114:23-56:4712.00PM2 J1443-604.75 36914:43-60:320.78PM1 J1623-080.50 6016:23-08:46154GBT350 J1739-25 18117:39-25:131.71*PM2 J1754-300.42 9817:54-30:110.60PM1 J1819-14584.2657619618:19:33.0-14:58:1617.62PM1 J1826-140.77 15918:26-14:271.06PM1 J1839-010.93 30718:39-01:360.62PM1 J1840-061.59 77318:40-06:2513.71PM2 J1846-024.47 23918:46-02:561.10PM1 J1848-126.79 8818:48-12:471.25PM1 J1911+00 10019:11+00:370.31PM1 J1913+1330.927.8717519:13:17.6+13:33:20.14.71PM 1 J1928+150.40 19:28+1590PALFA http://www.as.wvu.edu/~pulsar/rratalog/

4. About RRAT J1819-1458 Mclaughlin et al. 2006, Nature ， 439, 817 Burst rate: 17 per hour Burst duration: 2 ms Peak flux : ~3.6 Jy Single pulses timing P: 4.26 s P-dot: 576 10 -15 s/s DM: 196 (3) pc cm -3 Age: 117 Kyr B surf : 5 × 10 13 Gauss Radio observations X-ray observations The Chandra observation detected the X-ray counterpart (Reynolds et al. 2006). XMM–Newton, discovered the X-ray pulsations with the period predicted by the timing of radio bursts. Mclaughlin et al. (2007) So, what is it?

5. Observation system and de-dispersion method 128 channels, with bandwidth 2.5M Hz 2 polarizations, Center frequency is 1540M Hz

6. Observations of RRATs Giant pulses of some pulsars Search of extremely strong pulses from pulsars PSR B0656+14 Weltevrede et al. 2006 ， ApJ ， 645 ， 147 Small-time-scale radio transients search Monitoring of magnetars (AXP & SGRs) Based on the Filter-Bank de-dispersion system, We developed software to search rare and strong single pulses. Since March 2007: Identifying the signal

7. Long Term monitoring of RRAT J1819-1458 -- Timing results from 162 bursts Updated to Mar. 2008 Esamdin et al. 2008 ， MNRAS, 389, 1399 DM=196.0(4)

8. Long Term monitoring of RRAT J1819-1458 -- Timing results from 162 bursts Single pulse timing ： Updated to Mar. 2008 Esamdin et al. 2008 ， MNRAS, 389, 1399

9. Long Term monitoring of RRAT J1819-1458 -- Timing results from 162 bursts Timing position Timing residuals and pulse phases Bimodal distribution of pulse phase? In fact, there are even more… Updated to Mar. 2008 Esamdin et al. 2008 ， MNRAS, 389, 1399

10. About 350 strong bursts detected updated to June 2009 Long-Term monitoring of RRAT J1819-1458 Timing irregularity: First glitch detected in RRAT ？ Epoch around MJD 54580

11. Long-Term monitoring of RRAT J1819-1458 Top left: Timing residuals with 1 st glitch fitted. Bottom right: Timing residuals with both glitches fitted

12. Long Term monitoring of RRAT J1819-1458 Glitch parameters got: Glitch parameters got: Epoch of Glitch 1: MJD 54572 Epoch of Glitch 1: MJD 54572 Δν: 1.989(8)×10 -09 Hz Δν: 1.989(8)×10 -09 Hz ν(dot):8.11(7)×10 -17 Hz s -1 ν(dot):8.11(7)×10 -17 Hz s -1 Epoch of Glitch 2: MJD 54870 Epoch of Glitch 2: MJD 54870 Δν: 1.02(1) ×10 -09 Hz Δν: 1.02(1) ×10 -09 Hz ν(dot): 1.8(2) ×10 -17 Hz s -1 ν(dot): 1.8(2) ×10 -17 Hz s -1 The second glitch is too small?

13. Long Term monitoring of RRAT J1819-1458

14. Summary: In observation of hundreds of hours, we detected about 350 dispersed bursts of RRAT J1819−1458 with the signal-to-noise ratios (S/Ns) above 5 σ threshold. The S/N of the strongest burst is 13.3. The source’s DM measured through our data is 196.0 ± 0.4 pc cm −3. Our timing position with 2σ error is consistent with the position of its X-ray counterpart CXOU J181934.1−145804. 2 glitches detected in observation during 800 days, with first one at MJD 54572, the other one at MJD 54870. The distribution of the timing residuals is bimodal before the first glitch, but has only one main component between the 2 glitches, and becomes bimodal again after the second glitch. Careful study of the radio bursts properties is necessary to get a more accurate parameter of the second glitch. Long Term monitoring of RRAT J1819-1458

15. Thanks! And, Thanks to YUAN J.P. ZHAO C.S. and A. Esamdin