Skip to content
DraconiticResearch
Search Sources API
203,948 studies31 sourcesUpdated 45 min ago
PreprintarXiv licencearXiv

In-flight Timing Calibration of the Follow-up X-Ray Telescope on Board the Einstein Probe

  • Juan Zhang
  • Xiaofan Zhao
  • Dawei Han
  • Hao Wang
  • Yong Chen
  • Mingyu Ge
  • Shijie Zheng
  • Shumei Jia
  • Haisheng Zhao
  • Weiwei Cui
  • Hanlong Peng
  • Wentao Ye
9 more authors
  • Yaoming Duan
  • Youli Tuo
  • Zhen Ji
  • Fuli Ma
  • Chengkui Li
  • Ju Guan
  • Jingjing Xu
  • Jin Wang
  • Liming Song
Open at sourcePDFDOICite

Abstract

After the launch of Einstein Probe (EP), pulsars are observed to calibrate the timing system of the onboard Follow-up X-ray Telescope (FXT) by measuring the times of arrival (TOAs). FXT has two independently operating modules, namely FXTA and FXTB, each equipped with the Wolter-I optics and the pnCCD camera. For scientific observations, each pnCCD has three distinct readout modes that differ in frame cycles, the full frame mode (FF, 50 ms per frame), the partial windowed mode (PW, 2.2 ms per frame), and the timing mode (TM, 23.68 μs per row, 9.4352 ms per frame). Thus, 1RXS J170849.0--400910 with the spin period of 11 s is observed in FF, PSR B1509--58 (150 ms) in PW, and Crab pulsar (33 ms) in TM as well as PSR B1821--24 (3.05 ms) and PSR B1937+21 (1.56 ms). The TOAs of these pulsars measured by FXTA and FXTB are compared with the results of NICER, and for Crab pulsar with the Jodrell Bank Monthly Ephemeris (JBE). Results verify that the timing system of FXTA and FXTB in FF, PW, and TM modes are consistent with each other, and are in good alignment with NICER. The measured advance of the Crab pulsar's main peak relative to JBE is 357±14(stat)±54(sys) μs in FXTA and 394±14(stat)±67(sys) μs in FXTB. Based on measurements of PSR B1821--24 and PSR B1937+21, the preliminary absolute timing accuracy is estimated to be 6 μs for FXTA and 31 μs for FXTB in TM mode. Additionally, the systematic delay of FXTA timing results relative to FXTB is found to be 20±19(stat)±21(sys) μs.

Versions

Related

  1. Detecting seven new glitches in PSR J1341-6220 using six-year timing observations from the Parkes 64 m radio telescope
    L. H. Shang, Y. L. Liang, Y. Z. Qiao +2
    Astronomy & AstrophysicsPeer-reviewedPublisher termsHigh-energy astrophysicsCrossref
  2. First overnight balloon flight of the GRAINE 2023 emulsion gamma-ray telescope enabled by a large-scale pressure-vessel gondola
    Hiroki Rokujo, Shigeki Aoki, Takashi Azuma +34
    arXivPreprintarXiv licenceFull textInstrumentation & methodsarXiv
  3. Environmental Noise Challenges for the Einstein Telescope - A Review
    Matteo Di Giovanni
    arXivPreprintCC BY 4.0Full textInstrumentation & methodsGravitation & general relativityarXiv
  4. Scalable and sequential inference of the neutron star equation of state with the Einstein Telescope
    Thibeau Wouters, Thomas C. K. Ng, Hauke Koehn +4
    arXivPreprintCC BY 4.0Full textHigh-energy astrophysicsGravitation & general relativityarXiv
  5. Detection of cosmic strings by gravitational wave lensing. Predictions for Einstein Telescope
    Jakub Szyndler, Tomasz Bulik
    arXivPreprintCC BY 4.0Full textCosmologyGravitation & general relativityarXiv

Cite

BibTeXRIS
BibTeX
@misc{zhang2026inflight,
  title = {{In-flight Timing Calibration of the Follow-up X-Ray Telescope on Board the Einstein Probe}},
  author = {Juan Zhang and Xiaofan Zhao and Dawei Han and Hao Wang and Yong Chen and Mingyu Ge and Shijie Zheng and Shumei Jia and Haisheng Zhao and Weiwei Cui and Hanlong Peng and Wentao Ye and Yaoming Duan and Youli Tuo and Zhen Ji and Fuli Ma and Chengkui Li and Ju Guan and Jingjing Xu and Jin Wang and Liming Song},
  howpublished = {arXiv},
  year = {2026},
  month = oct,
  doi = {10.48550/arxiv.2610.12943},
  eprint = {2610.12943},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2610.12943},
}
RIS
TY  - UNPB
TI  - In-flight Timing Calibration of the Follow-up X-Ray Telescope on Board the Einstein Probe
AU  - Juan Zhang
AU  - Xiaofan Zhao
AU  - Dawei Han
AU  - Hao Wang
AU  - Yong Chen
AU  - Mingyu Ge
AU  - Shijie Zheng
AU  - Shumei Jia
AU  - Haisheng Zhao
AU  - Weiwei Cui
AU  - Hanlong Peng
AU  - Wentao Ye
AU  - Yaoming Duan
AU  - Youli Tuo
AU  - Zhen Ji
AU  - Fuli Ma
AU  - Chengkui Li
AU  - Ju Guan
AU  - Jingjing Xu
AU  - Jin Wang
AU  - Liming Song
PY  - 2026
DA  - 2026/10/09
PB  - arXiv
DO  - 10.48550/arxiv.2610.12943
UR  - https://arxiv.org/abs/2610.12943
AB  - After the launch of Einstein Probe (EP), pulsars are observed to calibrate the timing system of the onboard Follow-up X-ray Telescope (FXT) by measuring the times of arrival (TOAs). FXT has two independently operating modules, namely FXTA and FXTB, each equipped with the Wolter-I optics and the pnCCD camera. For scientific observations, each pnCCD has three distinct readout modes that differ in frame cycles, the full frame mode (FF, 50 ms per frame), the partial windowed mode (PW, 2.2 ms per frame), and the timing mode (TM, 23.68 μs per row, 9.4352 ms per frame). Thus, 1RXS J170849.0--400910 with the spin period of 11 s is observed in FF, PSR B1509--58 (150 ms) in PW, and Crab pulsar (33 ms) in TM as well as PSR B1821--24 (3.05 ms) and PSR B1937+21 (1.56 ms). The TOAs of these pulsars measured by FXTA and FXTB are compared with the results of NICER, and for Crab pulsar with the Jodrell Bank Monthly Ephemeris (JBE). Results verify that the timing system of FXTA and FXTB in FF, PW, and TM modes are consistent with each other, and are in good alignment with NICER. The measured advance of the Crab pulsar's main peak relative to JBE is 357^±14(stat)_±54(sys) μs in FXTA and 394^±14(stat)_±67(sys) μs in FXTB. Based on measurements of PSR B1821--24 and PSR B1937+21, the preliminary absolute timing accuracy is estimated to be 6 μs for FXTA and 31 μs for FXTB in TM mode. Additionally, the systematic delay of FXTA timing results relative to FXTB is found to be 20^±19(stat)_±21(sys) μs.
ER  -