J/MNRAS/504/5907 OGLE Bulge short-period sample (Gomel+, 2021)
Search for dormant black holes in ellipsoidal variables.
III. The OGLE Bulge short-period sample.
Gomel R., Faigler S., Mazeh T., Pawlak M.
<Mon. Not. R. Astron. Soc. 504, 5907-5918 (2021)>
=2021MNRAS.504.5907G 2021MNRAS.504.5907G (SIMBAD/NED BibCode)
ADC_Keywords: Surveys ; Photometry ; Stars, variable
Keywords: methods: data analysis - techniques: photometric - binaries: close -
stars: black holes
Abstract:
This is the third of a series of papers that presents an algorithm to
search for close binaries with massive, possibly compact, unseen
secondaries. The detection of such a binary is based on identifying a
star that displays a large ellipsoidal periodic modulation, induced by
tidal interaction with its companion. In the second paper of the
series, we presented a simple approach to derive a robust modified
minimum mass ratio (mMMR), based on the observed ellipsoidal
amplitude, without knowing the primary mass and radius, assuming the
primary fills its Roche lobe. The newly defined mMMR is always smaller
than the actual mass ratio. Therefore, a binary with an mMMR larger
than unity is a good candidate for having a massive secondary, which
might be a black hole or a neutron star. This paper considers 10956
OGLE short-period ellipsoidals observed towards the Galactic bulge. We
re-analyse their modulation and identify 136 main-sequence systems
with mMMR significantly larger than unity as candidates for having
compact-object secondaries, assuming their observed periodic
modulations reflect indeed the ellipsoidal effect. Obviously, one
needs follow-up observations to find out the true nature of these
companions.
Description:
This catalog contains 10812 OGLE short-period ellipsoidals observed
towards the Galactic Bulge. We re-analysed each lightcurve modulation,
and derived for each system its modified minimum mass ratio (mMMR).
We also identified 137 main-sequence systems with lower-percentile
mMMR larger than unity as candidates for having compact-object
secondaries.
Each system parameters are given in a single line.
Given below a summary table containing results of the analysis
performed on 10812 short-period ellipsoidals.
Each system parameters are given in a single line.
The listed parameters are:
OGLE ID (last six digits), OGLE orbital period [days], reference time
[JD-2450000], reference-time error, fitted I magnitude, fitted I
magnitude error, cosine and sine Fourier coefficients, each followed
by its error [mag], total number of analyzed points, total number of
analyzed seasons, light-curve time range [days], reduced chi-square of
the four-harmonic model, mMMR and lower-percentile mMMR.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
tableb1.dat 282 10812 OGLE short-period ellipsoidals
--------------------------------------------------------------------------------
See also:
J/AcA/66/405 : Galactic bulge eclipsing + ellipsoidal binaries
(Soszynski+, 2016)
Byte-by-byte Description of file: tableb1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 A19 --- ID Star's ID (OGLE-BLG-NNN-NNNNNN)
21- 28 F8.4 deg RAdeg Right ascension (J2000.0)
30- 37 F8.4 deg DEdeg Declination (J2000.0)
39- 46 F8.6 d P OGLE orbital period
48- 58 F11.6 d T0 Reference time [JD-2450000]
60- 67 F8.6 d e_T0 Reference-time error
69- 77 F9.6 mag Imag Fitted I magnitude
79- 86 F8.6 mag e_Imag Fitted I magnitude error
88- 96 F9.6 mag a1c Cosine coefficient of first harmonic
99-106 F8.6 mag e_a1c a1c error
109-116 F8.6 mag a2c Cosine coefficient of second harmonic
119-126 F8.6 mag e_a2c a2c error
128-136 F9.6 mag a3c Cosine coefficient of third harmonic
139-146 F8.6 mag e_a3c a3c error
148-156 F9.6 mag a4c Cosine coefficient of forth harmonic
159-166 F8.6 mag e_a4c a4c error
168-176 F9.6 mag a1s Sine coefficient of first harmonic
179-186 F8.6 mag e_a1s a1s error
189-196 F8.6 mag a2s Sine coefficient of second harmonic
199-206 F8.6 mag e_a2s a2s error
208-216 F9.6 mag a3s Sine coefficient of third harmonic
219-226 F8.6 mag e_a3s a3s error
228-236 F9.6 mag a4s Sine coefficient of forth harmonic
239-246 F8.6 mag e_a4s a4s error
248-252 I5 --- N Total number of analyzed points
254 I1 --- Ns Total number of analyzed seasons
256-259 I4 d TimeRange Light-curve time range
261-266 F6.2 --- chis Reduced chi-square of a four-harmonic model
268-274 F7.4 --- mMMR Modified minimum mass ratio
276-282 F7.4 --- mMMR1sig Lower-percentile mMMR
--------------------------------------------------------------------------------
Acknowledgements:
Roy Gomel, roygomel6(at)gmail.com
References:
Gomel et al., Paper I 2021MNRAS.501.2822G 2021MNRAS.501.2822G
Gomel et al. Paper II 2021MNRAS.504.2115G 2021MNRAS.504.2115G
(End) Patricia Vannier [CDS] 29-Apr-2021