J/MNRAS/517/257 1782 Mira variables candidates with VVV survey (Sanders+, 2022)
Mira variables in the Milky Way's nuclear stellar disc discovery and
classification
Sanders J.L., Matsunaga N., Kawata D., Smith L.C., Minniti D., Lucas P.W.
<Mon. Not. R. Astron. Soc. 517, 257-280 (2022)>
=2022MNRAS.517..257S 2022MNRAS.517..257S (SIMBAD/NED BibCode)
ADC_Keywords: Stars, variable ; Stars, giant ; Milky Way ; Infrared ;
Photometry ; Positional data ; Spectroscopy ; Mass loss
Keywords: stars: AGB and post-AGB - stars: variables: general - Galaxy: bulge -
Galaxy: centre - Galaxy: stellar content
Abstract:
The properties of the Milky Way's nuclear stellar disc give crucial
information on the epoch of bar formation. Mira variables are
promising bright candidates to study the nuclear stellar disc, and
through their period-age relation dissect its star formation history.
We report on a sample of 1782 Mira variable candidates across the
central 3*3 deg2 of the Galaxy using the multi-epoch infrared VISTA
Variables in Via Lactea (VVV) survey. We describe the algorithms
employed to select candidate variable stars and then model their light
curves using periodogram and Gaussian process methods. By combining
with WISE, 2MASS, and other archival photometry, we model the
multiband light curves to refine the periods and inspect the amplitude
variation between different photometric bands. The infrared brightness
of the Mira variables means many are too bright and missed by VVV.
However, our sample follows a well-defined selection function as
expected from artificial star tests. The multiband photometry is
modelled using stellar models with circumstellar dust that
characterize the mass-loss rates. We demonstrate how ~>90 per cent of
our sample is consistent with O-rich chemistry. Comparison to
period-luminosity relations demonstrates that the bulk of the short
period stars are situated at the Galactic Centre distance. Many of the
longer period variables are very dusty, falling significantly under
the O-rich Magellanic Cloud and solar neighbourhood period-luminosity
relations and exhibit high mass-loss rates of
∼2.5*10-5M☉yr-1. The period distribution appears consistent
with the nuclear stellar disc forming ~> 8 Gyr ago, although it is not
possible to disentangle the relative contributions of the nuclear
stellar disc and the contaminating bulge.
Description:
We describe the sequence of steps taken to extract a sample of NSD
Mira variable candidates with VISTA VVV multi epoch survey in infrared
ZYJHKs bands by analysing thousands of light curves variability. As
described in section 2, we supplemented this survey with 2MASS, WISE,
AKARI and other in order to cover a wide range of wavelength. To
select reliable Mira variable candidates we extract properties from
precise light curve modelling. Selection cuts on photometry values and
its variabilities provide final properties catalog in table.dat with
1782 Mira variable candidates. Further, a spectral fit analysis allows
us to characterize the properties of the Mira variable sample as
optical depths, expansion velocity, mass loss rates from a dust model
(i.e section 3).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table.dat 536 1782 Photometric and spectroscopic properties of
our Mira variable candidates sample
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See also:
J/MNRAS/509/2566 : VIVACE, VIrac VAriable Classification Ensemble
(Molnar+, 2022)
J/MNRAS/483/5150 : Variables in NGC 3109 dwarf irregular galaxy (Menzies+,2019)
J/MNRAS/483/3022 : Age gradients throughout the Galaxy with LPVs (Grady+, 2019)
J/MNRAS/482/5567 : Stellar variability in Galactic Centre
(Navarro Molina+, 2019)
J/MNRAS/455/2216 : Outer bulge O-rich Mira's JHKL photometry (Catchpole+, 2016)
J/MNRAS/452/910 : IC 1613 asymptotic giant branch variables (Menzies+, 2015)
J/MNRAS/414/3492 : JHKs photometry of Sculptor dSph galaxy (Menzies+, 2011)
J/MNRAS/399/1709 : Near-infrared survey of Miras (Matsunaga+, 2009)
J/MNRAS/386/313 : IR observations of Mira variables (Whitelock+, 2008)
J/MNRAS/321/77 : Large-amplitude variables near the Galactic Centre
(Glass+, 2001)
J/MNRAS/317/460 : Kinematics of Mira stars (Feast+, 2000)
J/ApJ/919/99 : WISE & Spitzer obs. of OGLE Miras in the LMC (Iwanek+, 2021)
J/ApJ/901/109 : Ages & [Fe/H] of the MW bulge using APOGEE
(Hasselquist+, 2020)
J/ApJ/889/5 : HST obs. of Mira variables in the SNIa host NGC1559
(Huang+, 2020)
J/ApJ/884/20 : OGLE-III Mira variables in the Magellanic Clouds
(Bhardwaj+, 2019)
J/ApJ/877/49 : DUSTiNGS. V. 3.6 and 4.5um light curves (Goldman+, 2019)
J/ApJ/857/67 : HST obs. of Mira candidates in NGC 4258 (Huang+, 2018)
J/ApJ/737/73 : Infrared extinction toward the Galactic Centre (Fritz+,2011)
J/ApJ/723/1195 : SAGE AGB candidates (Riebel+, 2010)
J/ApJS/257/23 : Multiwavelength obs. of Miras in the LMC (Iwanek+, 2021)
J/ApJS/256/43 : O-rich and C-rich AGB stars in our Galaxy (Suh, 2021)
J/AJ/163/192 : 807 Mira variable stars photometry in Magellanic Clouds
(Ou+, 2022)
J/AJ/154/149 : LMC NIR synoptic survey. V. NIR photometry of Miras
(Yuan+, 2017)
J/AJ/153/170 : The M33 Synoptic Stellar Survey. II. Mira variables
(Yuan+, 2017)
J/AJ/152/164 : I-band light curves of OGLE LMC Miras (He+, 2016)
J/AJ/149/64 : MIPSGAL 24µm point source catalog (Gutermuth+, 2015)
J/AJ/136/1242 : LMC long-period variables from MACHO (Fraser+, 2008)
J/AJ/136/1221 : Most luminous LMC sources at 8µm (Kastner+, 2008)
J/A+A/662/A11 : Milky Way's Nuclear Stellar Disc pm catalog
(Shahzamanian+, 2022)
J/A+A/660/A35 : VVV survey. Long-period variable stars (Nikzat+, 2022)
J/A+A/642/A81 : APOGEE cool stars (Schultheis+, 2020)
J/A+A/631/A20 : GALACTICNUCLEUS JHKs imaging survey. II.
(Nogueras-Lara+, 2019)
J/A+A/609/A114 : Local Group AGB stars and red supergiants
(Groenewegen+, 2018)
J/A+A/564/A84 : WISE model grids for O- and C-rich AGB (Lian+, 2014)
J/A+A/549/A147 : Abundances of microlensed bulge dwarf stars. V.
(Bensby+, 2013)
J/A+A/442/281 : Late-type giants BVRIJHKL and Teff calibration
(Kucinskas+, 2005)
J/A+A/503/913 : Synthetic spectrophotometry for C-rich giants
(Aringer+, 2009)
J/AcA/63/21 : VI light curves of Galactic LPVs (Soszynski+, 2013)
J/AcA/59/239 : VI light curves of LMC long-period variables
(Soszynski+, 2009)
VII/233 : 2MASS All-Sky Extended Source Catalog (XSC)
(IPAC-UMass, 2003-2006)
II/376 : VISTA Variable in the Via Lactea Survey (VVV) DR4.2
(Minniti+, 2023)
II/364 : VIRAC. The VVV Infrared Astrometric Catalogue (Smith+, 2019)
II/337 : VISTA Variables in the Via Lactea Survey DR1 (Saito+, 2012)
II/311 : WISE All-Sky Data Release (Cutri+ 2012)
II/297 : AKARI/IRC mid-IR all-sky Survey (ISAS/JAXA, 2010)
II/243 : The ISOGAL Point Source Catalogue - IGPSC (Omont+ 2003)
I/337 : Gaia DR1 (Gaia Collaboration, 2016)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
Byte-by-byte Description of file: table.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- ID Identifier raw number (viracmiraid)
6- 21 F16.12 deg RAdeg Right ascension (J2000) (ra)
23- 39 F17.13 deg DEdeg Declination (J2000) (dec)
41- 59 F19.15 deg GLON Galactic longitude (l)
61- 78 F18.15 deg GLAT Galactic latitude (b)
80- 83 I4 --- IDm09 ? Sequential number from NIR survey of Miras
from Matsunaga et al. 2009MNRAS.399.1709M 2009MNRAS.399.1709M,
Cat. J/MNRAS/399/1709 (M09_id)
85 I1 --- Flag Unreliable detection flag (unreliable) (1)
87- 89 I3 --- Nepochs Number of KS epochs in the light curves,
i.e see section 2.2 and Nepochs
distribution in its figure 4 Ks_nepochs
(Ks_nepochs)
91- 98 F8.4 d P Assigned variability period (period)
100-109 F10.6 d e_P ? Mean error of P period_error
(period_error)
111-118 F8.6 mag Amp Assigned variability amplitude in KS
magnitude (amplitude)
120-127 F8.6 mag TotAmp ? Total variability amplitude in KS
magnitude (total_amplitude)
129-136 F8.4 d Ps Period obtained with single light curve
method (period_single)
138-147 F10.6 d e_Ps ? Mean error of Ps (perioderrorsingle)
149-156 F8.6 mag Amps ? Variability amplitude with single light
curve method (amplitude_single)
158-165 F8.6 mg TotAmps ? Total variability amplitude with single
light curve method (totalamplitudesingle)
167-176 F10.4 d Pm Period obtained from multi-epoch and
multi-bands analysis (period_multi)
178-189 E12.6 d e_Pm ? Mean error of Pm (perioderrormulti)
191-198 F8.6 mag Ampm Variability amplitude from multi-epoch and
multi-bands analysis (amplitude_multi)
200-211 E12.6 mag TotAmpm Otal variability amplitude from multi-epoch
and multi-bands analysis
(totalamplitudemulti)
213-219 F7.4 mag Zmag ? Mean apparent magnitude in Vista Z filter
(Zmeandata)
221-227 F7.4 mag Ymag ? Mean apparent magnitude in Vista Y filter
(Ymeandata)
229-235 F7.4 mag Jmag ? Mean apparent magnitude in Vista J filter
(Jmeandata)
237-243 F7.4 mag Hmag ? Mean apparent magnitude in Vista H filter
(Hmeandata)
245-252 F8.5 mag Ksmag ? Mean apparent magnitude in Vista Ks
filter (Ksmeandata)
254-261 F8.5 mag KsSmag ? Mean apparent magnitude in Vista Ks
filter for the single model
(Ksmeanmodel_single)
263-270 F8.6 mag e_KsSmag ? Mean error of KsSmag
(Kserrormodel_single)
272-278 F7.4 mag ZMmag ? Mean apparent magnitude in Vista Z filter
for the multi-epoch and multi-bands light
curve model (Zmeanmodel)
280-286 F7.4 mag YMmag ? Mean apparent magnitude in Vista Y filter
for the multi-epoch and multi-bands light
curve model (Ymeanmodel)
288-295 F8.5 mag JMmag ? Mean apparent magnitude in Vista J filter
for the multi-epoch and multi-bands light
curve model (Jmeanmodel)
297-304 F8.5 mag HMmag ? Mean apparent magnitude in Vista H filter
for the multi-epoch and multi-bands light
curve model (Hmeanmodel)
306-313 F8.5 mag KsMmag ? Mean apparent magnitude in Vista Ks
filter for the multi-epoch and multi-bands
light curve model (Ksmeanmodel)
315-322 F8.5 mag W1Mmag ? Mean apparent magnitude in Wise W1 filter
for the multi-epoch and multi-bands light
curve model (W1meanmodel)
324-331 F8.5 mag W2Mmag ? Mean apparent magnitude in Wise W2 filter
for the multi-epoch and multi-bands light
curve model (W2meanmodel)
333-340 F8.6 mag e_ZMmag ? Mean error of ZMmag (Zerrormodel)
342-349 F8.6 mag e_YMmag ? Mean error of YMmag (Yerrormodel)
351-358 F8.6 mag e_JMmag ? Mean error of JMmag (Jerrormodel)
360-367 F8.6 mag e_HMmag ? Mean error of HMmag (Herrormodel)
369-376 F8.6 mag e_KsMmag Mean error of KsMmag (Kserrormodel)
378-385 F8.6 mag e_W1Mmag ? Mean error of W1Mmag (W1errormodel)
387-394 F8.6 mag e_W2Mmag ? Mean error of W2Mmag (W2errormodel)
396-403 F8.6 --- AmpZ/Ks ? Z to Ks amplitude ratio
ZKsamplitude_ratio (ZKsamplitude_ratio)
405-412 F8.6 --- AmpY/Ks ? Y to Ks amplitude ratio
YKsamplitude_ratio (YKsamplitude_ratio)
414-421 F8.6 --- AmpJ/Ks ? J to Ks amplitude ratio
JKsamplitude_ratio (JKsamplitude_ratio)
423-430 F8.6 --- AmpH/Ks ? H to Ks amplitude ratio
HKsamplitude_ratio (HKsamplitude_ratio)
432-439 F8.6 --- AmpW1/Ks ? W1 to Ks amplitude ratio
W1Ksamplitude_ratio
(W1Ksamplitude_ratio)
441-448 F8.6 --- AmpW2/Ks ? W2 to Ks amplitude ratio
W2Ksamplitude_ratio
(W2Ksamplitude_ratio)
450-457 F8.6 --- e_AmpZ/Ks ? Mean error of AmpZ/Ks
ZKsamplituderatioerror
(ZKsamplituderatioerror)
459-466 F8.6 --- e_AmpY/Ks ? Mean error of AmpY/Ks
YKsamplituderatioerror
(YKsamplituderatioerror)
468-475 F8.6 --- e_AmpJ/Ks ? Mean error of AmpJ/Ks
JKsamplituderatioerror
(JKsamplituderatioerror)
477-485 F9.6 --- e_AmpH/Ks ? Mean error of AmpH/Ks
HKsamplituderatioerror
(HKsamplituderatioerror)
487-495 F9.6 --- e_AmpW1/Ks ? Mean error of AmpW1/Ks
W1Ksamplituderatioerror
(W1Ksamplituderatioerror)
497-504 F8.6 --- e_AmpW2/Ks ? Mean error of AmpW2/Ks
W2Ksamplituderatioerror
(W2Ksamplituderatioerror)
506-514 F9.6 --- tau Optical depth at 10µm from spectral fit
analysis (opticaldepth10micron)
516-523 F8.5 km/s Vexp Expansion velocity from spectral fit
analysis (expansion_velocity)
525-536 E12.6 Msun/yr dM/dt Mass loss rates from spectral fit analysis
(masslossrate)
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Note (1): Unreliability flag explained below is as follows:
0 = Considerated as reliable Mira variable candidates,
1691 sources in our sample
1 = Unreliable Mira variable candidates, 91 sources in our sample
As mentionned in section 2.4 Multiband light curves, with the
multiband light curves in hand, we go through a final visual
inspection stage of our sample. We assess three aspects: (i) whether
the multiband light curve has perhaps produced spurious results
(possibly due to contaminated WISE observations) in which case we
resort to the results from the single Ks light-curve fit, (ii) whether
the light-curve fits have evidence of some periodicity but no clear
Mira-like oscillations in which case we flag the star as 'unreliable',
and (iii) whether there is no clear evidence for periodicity in which
case we remove the star from our sample. This visual inspection stage
removes 42 stars from our sample and flags 91 as unreliable.
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History:
From electronic version of the journal
(End) Luc Trabelsi [CDS] 01-Sep-2025