NICER observation list: Target ID 251101

Abstract

PSR B0540-69 recently transitioned to a previously unknown state with a 36% increase in spin-down rate and a large change in the braking index from 2.1 to near 0, a rare value for any pulsar. On-going Swift/XRT observations show that the pulsar remains in this new state. With its large effective area, low background, rapid readout, and accurate timing, NICER is by far the most efficient instrument for extending the ephemeris. We propose 12 short (200 s), monthly observations to maintain a phase-connected ephemeris; to search for a possible return to its old spin-down state; to measure the evolution in the braking index; to search for a change in the gamma-ray flux or pulse profile; and to improve our understanding of this extraordinary pulsar.
Obsid RA DEC l b Start End Exposure Number of
Modules
Number of
Processing
Status of
Processing
Date of
Processing
Public
date
2511010101 85.042 -69.332 279.718 -31.517 58562.6995 58562.7104 433.0 52 1 VALIDATED 58566.4 58576
2511010102 85.039 -69.329 279.715 -31.519 58563.6465 58563.6530 236.0 52 2 VALIDATED 58569.0 58577
2511010201 85.051 -69.335 279.721 -31.514 58594.0249 58594.0361 238.0 52 3 VALIDATED 58602.8 58608
2511010301 85.044 -69.329 279.714 -31.517 58624.7272 58624.7435 970.0 52 3 VALIDATED 58631.7 58638
2511010401 85.042 -69.334 279.720 -31.517 58654.0386 58654.0528 395.0 52 1 VALIDATED 58659.9 58668
2511010501 85.051 -69.330 279.714 -31.514 58684.7675 58684.7892 1388.0 52 3 VALIDATED 58690.1 58698
2511010601 85.044 -69.333 279.718 -31.516 58717.0748 58717.0845 523.0 52 2 VALIDATED 58721.8 58731
2511010701 85.047 -69.331 279.716 -31.515 58748.3238 58748.3962 516.0 52 3 VALIDATED 58752.9 58762
2511010801 85.046 -69.326 279.711 -31.516 58777.9806 58777.9935 519.0 52 3 VALIDATED 58782.7 58791