J/A+A/690/A220 CXOU J110926.4-650224 SALT spectra (Coti Zelati+, 2024)
Short-term variability of the transitional pulsar candidate CXOUJ110926.4-650224
from X-rays to infrared.
Coti Zelati F., de Martino D., Dhillon V.S., Marsh T.R., Vincentelli F.,
Campana S., Torres D.F., Papitto A., Baglio M.C., Miraval Zanon A., Rea N.,
Brink J., Buckley D.A.H., D'Avanzo P., Illiano G., Manca A., Marino A.
<Astron. Astrophys. 690, A220 (2024)>
=2024A&A...690A.220C 2024A&A...690A.220C (SIMBAD/NED BibCode)
ADC_Keywords: Pulsars ; X-ray sources ; Spectra, optical
Keywords: accretion, accretion discs - methods: data analysis -
methods: observational - techniques: photometric -
techniques: radial velocities - techniques: spectroscopic
Abstract:
CXOU J110926.4-650224 is a candidate transitional millisecond pulsar
(tMSP) with X-ray and radio emission properties reminiscent of those
observed in confirmed tMSPs in their X-ray 'subluminous' disc state.
We present the results of observing campaigns that, for the first
time, characterise the optical and near-infrared variability of this
source and establish a connection with the mode-switching phenomenon
observed in X-rays. The optical emission exhibited flickering
activity, frequent dipping episodes where it appeared redder, and a
multi-peaked flare where it was bluer. The variability pattern was
strongly correlated with that of the X-ray emission. Each dip matched
an X-ray low-mode episode, indicating that a significant portion of
the optical emission originates from nearly the same region as the
X-ray emission. The near-infrared emission also displayed remarkable
variability, including a dip of 20 min in length during which it
nearly vanished. Time-resolved optical spectroscopic observations
reveal significant changes in the properties of emission lines from
the disc and help infer the spectral type of the companion star to be
between K0 and K5. We compare the properties of CXOU J110926.4-650224
with those of other tMSPs in the X-ray subluminous disc state and
discuss our findings within the context of a recently proposed
scenario that explains the phenomenology exhibited by the prototypical
tMSP PPSR J1023+0038.
Description:
This dataset contains reduced observational data of the transitional
pulsar candidate CXOU J110926.4-650224 collected with the Southern
African Large Telescope (SALT). The tables provide flux density
measurements and spectral analysis across various wavelengths.
Objects:
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RA (2000) DE Designation(s)
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11 09 26.43 -65 02 24.9 CXOU J110926.4-650224 = 4PBC J1109.3-6501
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 114 112 List of fits and ascii spectrum files
20200521/* . 20 2020/05/21 SALT/RSS spectrum files (4576-6610Å)
20210402/* . 23 2021/04/02 SALT/RSS spectrum files (5800-7100Å)
20210403/* . 27 2021/04/03 SALT/RSS spectrum files (5800-7100Å)
20210404/* . 27 2021/04/04 SALT/RSS spectrum files (5800-7100Å)
20210406/* . 27 2021/04/06 SALT/RSS spectrum files (5800-7100Å)
20210408/* . 29 2021/04/08 SALT/RSS spectrum files (5800-7100Å)
20210409/* . 25 2021/04/09 SALT/RSS spectrum files (5800-7100Å)
20210410/* . 25 2021/04/10 SALT/RSS spectrum files (5800-7100Å)
20210422/* . 29 2021/04/22 SALT/RSS spectrum files (5800-7100Å)
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Description of file: 2020*/*.tx 2021*/*.txt
Byte-by-byte Description of file:
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Bytes Format Units Label Explanations
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1- 9 F9.4 0.1nm lambda Wavelenght
11- 22 E12.8 --- Flux Flux density
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 36 A36 --- FileName1 Name of the spectrum fits file
38- 70 A33 --- FileName2 Name of the spectrum ascii file
72-114 A43 --- Title Title of the files
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Acknowledgements:
Francesco Coti Zelati, cotizelati(at)ice.csic.es
(End) Patricia Vannier [CDS] 06-Sep-2024