J/AJ/166/116 OGLE-2019-BLG-0825 light curve (Satoh+, 2023)
OGLE-2019-BLG-0825: Constraints on the Source System and Effect on Binary-lens
Parameters Arising from a Five-day Xallarap Effect in a Candidate Planetary
Microlensing Event.
Satoh Y.K., Koshimoto N., Bennett D.P., Sumi T., Rattenbury N.J.,
Suzuki D., Miyazaki S., Bond I.A., Udalski A., Gould A., Bozza V.,
Dominik M., Hirao Y., Kondo I., Kirikawa R., Hamada R., Abe F., Barry R.,
Bhattacharya A., Fujii H., Fukui A., Fujita K., Ikeno T.,
Ishitani Silva S., Itow Y., Matsubara Y., Matsumoto S., Muraki Y.,
Niwa K., Okamura A., Olmschenk G., Ranc C., Toda T., Tomoyoshi M.,
Tristram P.J., Vandorou A., Yama H., Yamashita K., Mroz P., Poleski R.,
Skowron J., Szymanski M.K., Poleski R., Soszynski I., Pietrukowicz P.,
Kozlowski S., Ulaczyk K., Rybicki K.A., Iwanek P., Wrona M., Gromadzki M.,
Albrow M.D., Chung S.-J., Han C., Hwang K.-H., Kim D., Jung Y.K.,
Kim H.W., Ryu Y.-H., Shin I.-G., Shvartzvald Y., Yang H., Yee J.C.,
Zang W., Cha S.-M., Kim D.-J., Kim S.-L., Lee C.-U., Lee D.-J., Lee Y.,
Park B.-G., Pogge R.W., Jorgensen U.G., Longa-Pena P., Sajadian S.,
Skottfelt J., Snodgrass C., Tregloan-Reed J., Bach-Moller N., Burgdorf M.,
D'Ago G., Haikala L., Hitchcock J., Hundertmark M., Khalouei E.,
Peixinho N., Rahvar S., Southworth J., Spyratos P., Leading Authors,
The MOA Collaboration, The OGLE Collaboration, The KMTNet Collaboration,
The MiNDSTEp Collaboration
<Astron. J., 166, 116 (2023)>
=2023AJ....166..116S 2023AJ....166..116S
ADC_Keywords: Gravitational lensing; Optical; Photometry
Keywords: Gravitational microlensing ; Brown dwarfs ; Xallarap effect
Abstract:
We present an analysis of microlensing event OGLE-2019-BLG-0825. This
event was identified as a planetary candidate by preliminary modeling.
We find that significant residuals from the best-fit static
binary-lens model exist and a xallarap effect can fit the residuals
very well and significantly improves χ2 values. On the other hand,
by including the xallarap effect in our models, we find that
binary-lens parameters such as mass ratio, q, and separation, s,
cannot be constrained well. However, we also find that the parameters
for the source system such as the orbital period and semimajor axis
are consistent between all the models we analyzed. We therefore
constrain the properties of the source system better than the
properties of the lens system. The source system comprises a G-type
main-sequence star orbited by a brown dwarf with a period of P∼5days.
This analysis is the first to demonstrate that the xallarap effect
does affect binary-lens parameters in planetary events. It would not
be common for the presence or absence of the xallarap effect to affect
lens parameters in events with long orbital periods of the source
system or events with transits to caustics, but in other cases, such
as this event, the xallarap effect can affect binary-lens parameters.
Description:
Microlensing event OGLE-2019-BLG-0825 was first discovered on 2019
June 3 by the Optical Gravitational Lensing Experiment (OGLE)
collaboration. OGLE conducts a microlensing survey using the 1.3m
Warsaw Telescope with a CCD camera with a 1.4deg2 field of view
(FOV) at Las Campanas Observatory in Chile and distributes alerts of
the discovery of microlensing events by their OGLE-IV Early Warning
System. The event is located in the OGLE-IV field BLG534, which is
observed on the Cousins I band with an hourly cadence.
The Microlensing Observations in Astrophysics (MOA) collaboration also
independently discovered this event on 2019 June 23, and identified it
as MOA-2019-BLG-273 using the MOA alert system. The MOA collaboration
conducts a microlensing exoplanet survey toward the Galactic bulge
using the 1.8m MOA-II telescope with a CCD camera with a 2.2deg2
wide FOV, MOA-cam3, at the University of Canterbury's Mount John
Observatory in New Zealand.
The Korea Microlensing Telescope Network (KMTNet) collaboration
conducts a microlensing survey using three 1.6m telescopes each with a
CCD camera with a 4.0deg2 FOV. The telescopes are located at the
Cerro Tololo Inter-American Observatory (CTIO) in Chile, the South
African Astronomical Observatory (SAAO) in South Africa, and Siding
Spring Observatory (SSO) in Australia. This event is located in an
overlapping region with two KMTNet observed fields (KMTNet BLG01 and
BLG41), which are observed with high cadence once every 15 minutes,
and was discovered by the KMTNet EventFinder as KMT-2019-BLG-1389 on
2019 June 28.
The Danish telescope of MiNDSTEp (Microlensing Network for the
Detection of Small Terrestrial Exoplanets) made follow-up observations
in the I band. MiNDSTEp uses the 1.54m Danish Telescope at the
European Southern Observatory at La Silla Observatory in Chile. Data
from the Spitzer space telescope were also available, but these show
no detectable signal and so are not used.
Objects:
-----------------------------------------------------------------
RA (2000) DE Designation(s)
-----------------------------------------------------------------
17 52 21.61 -30 48 13.2 OGLE-2019-BLG-0825 = KMT-2019-BLG-1389
-----------------------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
fig1.dat 40 10743 Light curve for OGLE-2019-BLG-0825
--------------------------------------------------------------------------------
See also:
J/AJ/106/773 : Mass-luminosity relation (Henry+, 1993)
J/AcA/50/421 : OGLE-II DIA BUL_SC1 field (Wozniak, 2000)
J/ApJ/640/1051 : 25pc sample of Sun-like stars (Grether+, 2006)
J/A+A/450/681 : Companions to close spectroscopic binaries (Tokovinin+, 2006)
J/A+A/497/497 : Physical parameters from JHK flux (Gonzalez-Hernandez+, 2009)
J/A+A/504/959 : Amplitudes of single-mode Cepheids (Klagyivik+, 2009)
J/AcA/59/1 : VI light curves of LMC RR Lyrae stars (Soszynski+, 2009)
J/A+A/529/A75 : Limb-darkening coefficients (Claret+, 2011)
J/A+A/525/A95 : Search for brown-dwarf companions of stars (Sahlmann+, 2011)
J/AcA/61/1 : VI light curves of Galactic Bulge RR Lyrae (Soszynski+, 2011)
J/AcA/61/285 : VI light curves of Galactic Bulge Cepheids (Soszynski+, 2011)
J/A+A/549/A147 : Abundances of microlensed bulge dwarf stars V. (Bensby+, 2013)
J/A+A/587/A64 : Physical properties of giant exoplanets (Santerne+, 2016)
J/A+A/605/A79 : TGAS Cepheids and RR Lyrae stars (Gaia Collaboration+, 2017)
J/AJ/154/210 : 2015 high-cadence Spitzer microlensing events (Zhu+, 2017)
J/A+A/631/A125 : 54 massive companions detected with SOPHIE (Kiefer+, 2019)
J/ApJS/244/29 : Microlensing events toward the Galactic bulge (Mroz+, 2019)
J/ApJ/900/4 : Abundances & ages of stars in the Milky Way bulge (Sit+, 2020)
J/AJ/161/134 : Survey of stellar &planetary comp. within 25pc (Hirsch+, 2021)
J/A+A/645/A7 : Determining true mass RV exoplanets with Gaia (Kiefer+, 2021)
J/AJ/164/180 : Mass Prod 2021 KMTNet Microlensing Planets. I. (Ryu+, 2022)
Byte-by-byte Description of file: fig1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- Tel Telescope identifier
10- 20 F11.6 d HJD [8145/8791] Heliocentric Julian Date; HJD-2450000
22- 31 F10.2 --- Flux [-93288/3.2e6] Observed flux from Tel
33- 40 F8.2 --- e_Flux [4.23/58632] Uncertainty in Flux
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 22-Mar-2024