J/MNRAS/524/1826 Mon R2 photometry (Orcajo+, 2023)
Time-series photometry and multiwavelength characterization of the
young stellar cluster Mon R2.
Orcajo S., Cieza L.A., Gamen R.
<Mon. Not. R. Astron. Soc., 524, 1826-1854 (2023)>
=2023MNRAS.524.1826O 2023MNRAS.524.1826O (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, open ; Stars, variable ; Photometry ; Optical
Keywords: brown dwarfs - stars: fundamental parameters - stars: low-mass -
stars: rotation - stars: variables: general -
open clusters and associations: individual: Mon R2
Abstract:
Using the Las Cumbres Observatory Global Telescope Network (LCOGT), we
have obtained multi-epoch photometry of the young cluster Mon R2. We
have monitored over 6000 sources with i-band between 13 and 23 mag
within a 26x26 arcmin2 field of view. For each star, we collected
∼1500 photometric points covering a temporal window of 23d. Based on
these data, we have measured rotation-modulated of 136 stars and
identified around 90 additional variables, including 14 eclipsing
binary candidates. Moreover, we found 298 other variables with
photometric high-scatter. In addition, we have obtained r-band and
Hα narrow-band photometry of the cluster with LCOGT and
low-resolution optical spectroscopy of 229 stars with GMOS-Gemini. We
used the Gaia data from the periodic stars and objects with Hα
or IR-excesses, which are mostly low-mass pre-main sequence stars
(<1M☉) in the cluster to estimate the distance (825±51pc) and
the mean proper motions (µ_αcos(δ)=-2.75mas/yr and
µδ=1.15mas/yr) of its members. This allows us to use the
Gaia data to identify additional Mon R2 member candidates. We also
used Pan-STARRS photometry from our LCOGT sources to construct a more
precise H-R diagram, from which we estimate the mean age of the
cluster and identify other possible members including eleven
spectroscopy brown dwarf with M7 to M9 GMOS spectral types. Finally,
we combined our membership lists with Spitzer infrared photometry to
investigate the incidence of stars with discs and the effect these
have on stellar rotation.
Description:
We studied and characterized the young OC Mon R2 using a
multiwavelength and multitechnique approach. We used I-band
time-series photometry to monitor the stars and to identify
variability. We also used optical spectroscopy to determine the
spectral types in the low-mass regime. Moreover, we identified cluster
member candidates using different criteria, including variability,
proper motions from Gaia, disc indicators (IR colours, and Hα
emission) and the position in the H-R diagram.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
spitzer.dat 136 983 Spitzer data (table F1)
colour.dat 225 124 Colour excess values for 124 sources (table F3)
memcand.dat 159 1566 Objects with spectral type but not fulfilling
the membership criteria (table F4)
bdcand.dat 124 247 BD candidates (table F6)
listlc.dat 109 6842 List of light curves
lc/* . 6842 Individual light curves
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See also:
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
II/349 : The Pan-STARRS release 1 (PS1) Survey - DR1 (Chambers+, 2016)
II/368 : The Spitzer (SEIP) source list (SSTSL2) (Spitzer Science Center, 2021)
Byte-by-byte Description of file: spitzer.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 F6.1 --- Id Internal identification number
8- 9 I2 h RAh Right ascension (J2000)
11- 12 I2 min RAm Right ascension (J2000)
14- 20 F7.4 s RAs Right ascension (J2000)
22 A1 --- DE- Declination sign (J2000)
23- 24 I2 deg DEd Declination (J2000)
26- 27 I2 arcmin DEm Declination (J2000)
29- 34 F6.3 arcsec DEs Declination (J2000)
36- 43 F8.5 mag [3.6] Spitzer flux in magnitude for band [3.6],
in 3.6 aperture
45- 51 F7.5 mag e_[3.6] Error in band [3.6]
53- 61 F9.5 mag [4.5] ?=999 Spitzer flux in magnitude for band [4.5],
in 3.6 aperture
63- 71 F9.5 mag e_[4.5] ?=999 Error in band [4.5]
73- 81 F9.5 mag [5.8] ?=999 Spitzer flux in magnitude for band [5.8],
in 3.6 aperture
83- 92 F10.6 mag e_[5.8] ?=999 Error in band [5.8]
94-101 F8.5 mag [8.0] Spitzer flux in magnitude for band [8.0],
in 3.6 aperture
103-109 F7.5 mag e_[8.0] Error in band [8.0]
111 I1 --- Disc [0/1] Disc presence (disc=1 and no disc=0)
115-116 I2 --- Ref Reference (1)
118-136 A19 --- Spitzer Spitzer identification
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Note (1): References as follows:
1 = IRSA
2 = Gutermuth et al., 2009ApJS..184...18G 2009ApJS..184...18G, Cat. J/ApJS/184/18
3 = Kryukova et al., 2012AJ....144...31K 2012AJ....144...31K, Cat. J/AJ/144/31
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Byte-by-byte Description of file: colour.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 F6.1 --- Id Internal identification number
8- 9 I2 h RAh Right ascension (J2000)
11- 12 I2 min RAm Right ascension (J2000)
14- 20 F7.4 s RAs Right ascension (J2000)
22 A1 --- DE- Declination sign J2000
23- 24 I2 deg DEd Declination J2000
26- 27 I2 arcmin DEm Declination J2000
29- 34 F6.3 arcsec DEs Declination J2000
36 I1 --- Vtype [1/4]?=0 Variability type (G1)
40- 45 F6.3 d P ?=0 Period
47- 49 I3 --- Power Peak power of periodogram
51 I1 --- Vhs [0/1] High-scatter variables (1=yes, 0=no)
53- 56 A4 --- Halpha Halpha spectral line in emission (Ha),
in absorption (Ha-) and "HaCa" is Hα
and CaII emission line presence
58- 59 A2 --- SpType Spectral Type: M1 to M9,
"nonM" for earlier spectral types and
"N" for unidentified spectra
61- 63 I3 --- Disc [0/1]?=999 Excess in IR or Hα
(1=excess, 0=no excess)
65 I1 --- ZamsFlag [0/1] Object above zams in i-y colour
(1=yes, 0=no)
67 I1 --- GaiaFlag [0/1] Gaia candidate according us parameters
(1=yes, 0=no)
69- 87 I19 --- Gaia ?=- Gaia source identification
89-107 A19 --- Spitzer Spitzer source identification
109-126 I18 --- PS1 Pan-STARRS source identification
128-135 F8.4 mag E(g-r) ?=-99 Colour excess in E(g-r)
137-144 F8.4 mag e_E(g-r) ?=-99 Error in E(g-r)
146-153 F8.4 mag E(r-i) ?=-99 Colour excess in E(r-i)
155-162 F8.4 mag e_E(r-i) ?=-99 Error in E(r-i)
164-170 F7.4 mag E(z-y) Colour excess in E(z-y)
172-177 F6.4 mag e_E(z-y) Error in E(z-y)
179-186 F8.4 mag E(r-z) ?=-99 Colour excess in E(r-z)
188-195 F8.4 mag e_E(r-z) ?=-99 Error in E(r-z)
197-203 F7.4 mag E(i-z) Colour excess in E(i-z)
205-210 F6.4 mag e_E(i-z) Error in E(i-z)
212-218 F7.4 mag E(i-y) Colour excess in E(i-y)
220-225 F6.4 mag e_E(i-y) Error in E(i-y)
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Byte-by-byte Description of file: memcand.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 F6.1 --- Id Internal identification number
8- 9 I2 h RAh Right ascension (J2000)
11- 12 I2 min RAm Right ascension (J2000)
14- 20 F7.4 s RAs Right ascension (J2000)
22 A1 --- DE- Declination sign J2000
23- 24 I2 deg DEd Declination J2000
26- 27 I2 arcmin DEm Declination J2000
29- 34 F6.3 arcsec DEs Declination J2000
36- 42 F7.4 mag Imag Photometric instrumental I-band
44- 54 F11.9 mag e_Imag Instrumental rms I-band
56- 65 F10.7 mag dImag Differential magnitude
67 I1 --- Vtype [1/4]?=0 Variability type (G1)
69- 74 F6.3 d P ?=0 Period
76- 82 F7.3 --- Power Peak power of periodogram
84 I1 --- Vhs [0/1] High-scatter variables (1=yes, 0=no)
86- 89 A4 --- Halpha Hα spectral line in emission (Ha),
in absorption (Ha-) and "HaCa" is
Hα and CaII emission line presence
91- 94 A4 --- SpType Spectral Type: M1 to M9,
"nonM" for earlier spectral types and
"N" for unidentified spectra
96 I1 --- Disc [0/9]?=- Excess in IR or Hα
(1=excess, 0=no excess, 9=NaN)
98 I1 --- ZamsFlag [0/1]?=- Object above zams in i-y colour
(1=yes, 0=no)
100 I1 --- GaiaFlag [0/1]?=- Gaia candidate according us
parameters (1=yes, 0=no)
102-120 I19 --- Gaia ? Gaia source identification
122-140 A19 --- Spitzer Spitzer source identification
142-159 I18 --- PS1 ? Pan-STARRS source identification
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Byte-by-byte Description of file: bdcand.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 F6.1 --- Id Internal identification number
8- 9 I2 h RAh Right ascension (J2000)
11- 12 I2 min RAm Right ascension (J2000)
14- 20 F7.4 s RAs Right ascension (J2000)
22 A1 --- DE- Declination sign J2000
23- 24 I2 deg DEd Declination J2000
26- 27 I2 arcmin DEm Declination J2000
29- 34 F6.3 arcsec DEs Declination J2000
36 I1 --- Vtype [1/4]?=0 Variability type (G1)
40- 45 F6.3 d P ?=0 Period
47- 49 I3 --- Power Peak power of periodogram
51 I1 --- Vhs [0/1] High-scatter variables (1=yes, 0=no)
53 A1 --- Halpha [-] Hα spectral line in emission (Ha),
in absorption (Ha-) and "HaCa"
is Hα and CaII emission line presence
55 A1 --- SpType [-] Spectral Type: M1 to M9, "nonM" for
earlier spectral types and "N" for
unidentified spectra
57- 61 F5.1 --- Disc [0/1]?=999 Excess in IR or Hα
(1=excess, 0=no excess)
63 I1 --- ZamsFlag [0/1] Object above zams in i-y colour
(1=yes, 0=no)
65 I1 --- GaiaFlag [0/1] Gaia candidate according us parameters
(1=yes, 0=no)
67- 85 I19 --- Gaia ?=- Gaia source identification
87-105 A19 --- Spitzer Spitzer source identification
(JHHMMSS.ss+DDMMSS.s)
107-124 I18 --- PS1 ?=- Pan-STARRS source identification
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Byte-by-byte Description of file: listlc.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 F6.1 --- Id Internal identification number
8- 9 I2 h RAh Right ascension (J2000)
11- 12 I2 min RAm Right ascension (J2000)
14- 20 F7.4 s RAs Right ascension (J2000)
22 A1 --- DE- Declination sign (J2000)
23- 24 I2 deg DEd Declination (J2000)
26- 27 I2 arcmin DEm Declination (J2000)
29- 34 F6.3 arcsec DEs Declination (J2000)
36- 42 F7.4 mag Imag Average magnitude in I-band
44- 51 F8.6 mag e_Imag Standard deviation of the average magnitude
of the I-band
53- 62 F10.7 mag dImag Average I-band differential magnitude
64- 73 F10.8 mag e_dImag Standard deviation of the average
differential magnitude of I-band
75- 82 F8.4 --- power power of the periodogram
84 I1 --- VType [0/4] Type of variability (G1)
88- 98 F11.8 d Per Period (reliable for powers greater than 70)
100-109 A10 --- FileName Name fo the file with light curve data
in subdirectory lc
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Byte-by-byte Description of file: lc/*
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Bytes Format Units Label Explanations
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1- 4 I4 --- Id Internal identification number
6- 18 F13.7 d JD Julian date (JD-2400000)
20- 26 F7.4 mag dImag Differential magnitude in the I-band
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Global notes:
Note (G1): Variability type as follows:
1 = rotation modulated
2 = possible periodic
3 = binary
4 = other variability
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Acknowledgements:
Santi Orcajo, orcajosanti(at)gmail.com
(End) Patricia Vannier [CDS] 01-Sep-2023