J/A+A/694/A43 SMC High-Mass X-ray binaries variability (Treiber+, 2025)
Two decades of optical variability of Small Magellanic Cloud
high-mass X-ray binaries.
Treiber H., Vasilopoulos G., Bailyn C. D., Haberl F., Udalski A.
<Astron. Astrophys. 694, A43 (2025)>
=2025A&A...694A..43T 2025A&A...694A..43T (SIMBAD/NED BibCode)
ADC_Keywords: Binaries, X-ray ; Magellanic Clouds ; Photometry ; Optical
Keywords: stars: emission-line, Be - stars: neutron - pulsars: general -
Magellanic Clouds -
Abstract:
We present an analysis of the long-term optical/IR behavior of 111
high-mass X-ray binaries (HMXBs) in the Small Magellanic Cloud, based
on data from the OGLE collaboration. Most systems exhibit variability
on a range of timescales. This variability regulates the mass transfer
to the compact object, while the compact object can, in turn, affect
the donor star's behavior. To better understand this complex
interaction and the resulting X-ray properties in these systems, we
define a new taxonomy for the observed super-orbital variability. This
taxonomy connects to the color changes, orbital periods, and X-ray
behavior of the sources. In most cases, these properties can be
explained by differences between the flux of the disk around the Be
star and the flux from the star itself. We also refine and present new
potential orbital periods and sub-orbital variability in the sources.
Description:
table 2: Source numbers, which we use throughout this paper, increase
with increasing spin period and then with increasing RA for sources
without measured spin periods. The corresponding source number used by
Haberl & Sturm (2016A&A...586A..81H 2016A&A...586A..81H, Cat. J/A+A/586/A81) is indicated,
with Source #2 having two designations thanks to more recent studies
finding separately-cataloged sources to be the same system. OGLE IDs
are for OGLE IV unless otherwise noted. We indicate sources with
updated X-ray coordinates using the following letters: a:
2015ATel.8091....1K 2015ATel.8091....1K; b: 2014ATel.5772....1K 2014ATel.5772....1K; (c) 2018ATel12219....1G 2018ATel12219....1G.
table 3: The following letters indicate the origin of the established
period: X, H, C, B, G, M, and S designate periods from X-ray data, and
aggregated in Haberl et al. (2016A&A...586A..81H 2016A&A...586A..81H, Cat. J/A+A/586/A81),
Coe et al. (2015MNRAS.452..969C 2015MNRAS.452..969C), Bird et al. (2012MNRAS.423.3663B 2012MNRAS.423.3663B),
Gaudin et al. (2024ApJ...965L..10G 2024ApJ...965L..10G, 2024MNRAS.534.1937G 2024MNRAS.534.1937G), Maitra et
al. (2023ATel15886....1M 2023ATel15886....1M), and Sarraj et al. (2012IBVS.6030....1S 2012IBVS.6030....1S),
respectively. The X-ray period is from Galache et al.
(2008ApJS..177..189G 2008ApJS..177..189G) unless otherwise noted, where (a) is Schreier et
al. (1972ApJ...178L..71S 1972ApJ...178L..71S), (b) is Vasilopoulos et al.
(2017MNRAS.470.4354V 2017MNRAS.470.4354V), (c) is Townsend et al. (2011MNRAS.416.1556T 2011MNRAS.416.1556T),
(d) is Coe et al. (2014ATel.5766....1C 2014ATel.5766....1C), (e) is Townsend et al.
(2011MNRAS.416.1556T 2011MNRAS.416.1556T), (f) is Schurch et al. (2009MNRAS.392..361S 2009MNRAS.392..361S),
and (g) is Carpano et al. (2017A&A...602A..81C 2017A&A...602A..81C). We report the
periodogram peaks within 10% of each established period. The "Best Pd"
is the overall peak in the 2-200 day periodogram for the detrended
light curve, with the exception of eclipsing source SXP 182 and the
longer-period sources. We do not further investigate whether our "Best
Pd" is preferred over any periods established in the literature. While
we report a best period for any source with a peak above a false alarm
level of 0.001, only the periods surrounded by asterisks are
"confident" as defined in Sect. 5.2. Even then, there is a chance that
this strong signal is not orbital in origin, especially if it is an
alias of a system periodicity outside of the search range. For details
on the periodicity search, see Sect. 5. I-band values use the original
I mag data whereas V-I calculations use V mag data and I-band linearly
interpolated at the times of V mag observations. In the tenth
percentile I magnitude column, we mark with (c) sources with OGLE IV
manually calibrated to the median I magnitude of OGLE II and OGLE III.
For sources with unphysical OGLE II V-band measurements, we indicate
in the 90th percentile column that we only use III and IV for color
measurements. For the four sources without reliable color
measurements, we do not include any color information.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table2.dat 106 111 Identifying information of HMXBs in our sample
table3.dat 120 111 Optical properties of the sample
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See also:
J/A+A/586/A81 : High-mass X-ray binaries in the SMC (Haberl+, 2016)
J/MNRAS/466/1019 : Bright HMXBs in THINGS galaxies (Sazonov+, 2017)
J/A+A/665/A31 : Neutron-star kicks in HMXBs with Gaia EDR3 (Fortin+, 2022)
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Seq Source number
4 A1 --- n_Seq [abc] Note on Seq (1)
6- 10 A5 --- HS Source number in Haberl & Sturm
(2016A&A...586A..81H 2016A&A...586A..81H, Cat. J/A+A/586/A81)
13- 14 I2 h RAh X-ray Right Ascension (J2000)
16- 17 I2 min RAm X-ray Right Ascension (J2000)
19- 23 F5.2 s RAs X-ray Right Ascension (J2000)
26 A1 --- DE- X-ray Declination sign (J2000)
27- 28 I2 deg DEd X-ray Declination (J2000)
30- 31 I2 arcmin DEm X-ray Declination (J2000)
33- 36 F4.1 arcsec DEs X-ray Declination (J2000)
39- 41 F3.1 arcsec PosErr Position Error
43- 44 I2 h RAOh OGLE Right Ascension (J2000)
46- 47 I2 min RAOm OGLE Right Ascension (J2000)
49- 53 F5.2 s RAOs OGLE Right Ascension (J2000)
55 A1 --- DEO- OGLE Declination sign (J2000)
56- 57 I2 deg DEOd OGLE Declination sign (J2000)
59- 60 I2 arcmin DEOm OGLE Declination sign (J2000)
62- 65 F4.1 arcsec DEOs OGLE Declination sign (J2000)
67- 74 F8.3 s Pspin ? Spin period
79- 84 F6.2 d PorbXray ? Orbital period from X-ray
87-106 A20 --- OGLE OGLE identification
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Note (1): updated X-ray coordinates using the following letters:
a = Kennea et al.. 2015ATel.8091....1K 2015ATel.8091....1K
b = Krimm et al., 2014ATel.5772....1K 2014ATel.5772....1K
c = Guillot et al., 2018ATel12219....1G 2018ATel12219....1G
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Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Seq Name of the source
5 I1 --- Type Source type in taxonomy
7- 11 F5.2 mag BaseNum Base number
13- 16 F4.2 --- VarMetric Variability metric
18- 39 A22 d EstPds Established periods (1)
41- 63 A23 d NearEst Best near established periods (1)
65- 71 F7.2 d BestPd ? Best period
72 A1 --- n_BestPd [*] * for confident best period
74- 78 F5.2 mag b_Imag ? Tenth percentile OGLE I mag
79- 81 A3 --- n_Imag [(c) ] Note on Imag (2)
83- 87 F5.2 mag Imag ? Median OGLE I mag
89- 93 F5.2 mag B_Imag ? Ninetieth percentile OGLE I mag
95- 99 F5.2 mag b_V-I ? Tenth percentile OGLE V-I mag
100-105 A6 --- n_V-I [III/IV ] Note on V-I (3)
107-111 F5.2 mag V-I ? Median OGLE V-I mag
116-120 F5.2 mag B_V-I ? Ninetieth percentile OGLE V-I mag
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Note (1): The following letters indicate the origin of the established period:
X, H, C, B, G, M, and S designate periods from X-ray data, and
aggregated in Haberl et al. (2016A&A...586A..81H 2016A&A...586A..81H, Cat. J/AA+/586/A81),
Coe et al. (2015MNRAS.452..969C 2015MNRAS.452..969C), Bird et al. (2012MNRAS.423.3663B 2012MNRAS.423.3663B),
Gaudin et al. (2024ApJ...965L..10G 2024ApJ...965L..10G, 2024MNRAS.534.1937G 2024MNRAS.534.1937G),
Maitra et al. (2023ATel15886....1M 2023ATel15886....1M), and
Sarraj et al. (2012IBVS.6030....1S 2012IBVS.6030....1S), respectively.
The X-ray period is from Galache et al. (2008ApJS..177..189G 2008ApJS..177..189G) unless
otherwise noted, where
(a) is Schreier et al. (1972ApJ...178L..71S 1972ApJ...178L..71S),
(b) is Vasilopoulos et al. (2017MNRAS.470.4354V 2017MNRAS.470.4354V),
(c) is Townsend et al. (2011MNRAS),
(d) is Coe et al. (2014ATel.5766....1C 2014ATel.5766....1C),
(e) is Townsend et al. (2011MNRAS.416.1556T 2011MNRAS.416.1556T),
(f) is Schurch et al. (2009MNRAS.392..361S 2009MNRAS.392..361S), and
(g) is Carpano et al. (2017A&A...602A..81C 2017A&A...602A..81C)
Note (2): (c) for sources with OGLE IV manually calibrated to the median I
magnitude of OGLE II and OGLE III.
Note (3): III/IV for sources with unphysical OGLE II V-band measurements,
we indicate in the 90th percentile column that we only use III and IV
for color measurements.
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Acknowledgements:
Helena Treiber, lena.treiber(at)princeton.edu
(End) Helena Treiber [Princeton Univ., USA], Patricia Vannier [CDS] 22-Dec-2024