Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.atnf.csiro.au/research/pulsar/ppta/uploads/Main2/2012_09_05_van_Straten.pdf Дата изменения: Wed Sep 5 05:24:02 2012 Дата индексирования: Thu Feb 7 00:07:57 2013 Кодировка: Поисковые слова: universe

What's the deal with PSR J1022+1001?
Parkes Pulsar Timing Array Discussion 5 September 2012

Willem van Straten
1


PSR J1022+1001 profile


PSR J1022+1001
Camilo, F., Nice, D. J., Shrauner, J. A., & Taylor, J. H. 1996, ApJ, 469, 819 · using Arecibo and Greenbank · first observed profile shape variations "on a timescale of minutes" · limit to timing precision
3


PSR J1022+1001
Kramer, M., Xilouris, K. M., Camilo, F., Nice, D., Lange, C., Backer, D. C., & Doroshenko, O. 1999, ApJ, 520, 324 · using Effelsberg · observed profile shape variations in both time and frequency · EQUAD ~ 10 µs
4


5


Xilouris, K. M. 1991, A&A, 248, 323

Result in boost ~ 0.1

6


7


PSR J1022+1001
Ramachandran, R. & Kramer, M. 2003, A&A, 407, 1085 · using Westerbork = equatorial mount · therefore, no parallactic angle variation · does not imply instrumental stability!
­ automatic gain controllers ­ phase drift
8


PSR J1022+1001
Hotan, A. W., Bailes, M., & Ord, S. M. 2004, MNRAS, 355, 941 · · · · using Parkes no evidence for shape variations timing r.m.s ~ 2.2 µs 2/Nfree ~ 1.4
9


Template Matching
P() = aS(+ ) + b
FFT

P() = aS()e

-i2

+ ()b

10


11


12


Arrival Time Comparison

· 278 TOAS spanning 6.9 years
13