J/AJ/154/81 BVRI photometry of luminous stars in M31 and M33 (Martin+, 2017)
Multi-epoch BVRI photometry of luminous stars in M31 and M33.
Martin J.C., Humphreys R.M.
<Astron. J., 154, 81-81 (2017)>
=2017AJ....154...81M 2017AJ....154...81M (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, nearby ; Stars, nearby ; Stars, luminous ;
Stars, supergiant ; Photometry, UBVRI ; Stars, variable
Keywords: galaxies: individual (M31,M33) - stars: massive - supergiants
Abstract:
We present the first four years of BVRI photometry from an on-going
survey to annually monitor the photometric behavior of evolved
luminous stars in M31 and M33. Photometry was measured for 199 stars
at multiple epochs, including 9 classic Luminous Blue Variables
(LBVs), 22 LBV candidates, 10 post-RGB A/F type hypergiants, and 18
B[e] supergiants. At all epochs, the brightness is measured in the
V-band and at least one other band to a precision of 0.04-0.10 mag
down to a limiting magnitude of 19.0-19.5. Thirty three stars in our
survey exhibit significant variability, including at least two classic
LBVs caught in S Doradus-type outbursts. A hyperlinked version of the
photometry catalog is at http://go.uis.edu/m31m33photcat
Description:
Images were obtained of M31 and M33 using an Apogee U42 CCD Camera
with a back-illuminated E2v CCD42-40 chip on the F/13 20-inch (0.51m)
telescope at the University of Illinois Springfield Henry R. Barber
Research Observatory near Pleasant Plains, IL. The images are
19.4*19.4 arc minutes squares with a pixel scale of 0.57 arcseconds
per pixel.
Images were exposed in four high-throughput broad-band filters
manufactured by Astrodon: Johnson B and V, and Cousins R and I. The
B-filter does not have the red-leak present in most Astrodon B-filers
manufactured prior to 2013. Images were taken in V at every epoch
except one in 2012. In 2012, many fields were also imaged in R.
Imaging in the B-filter started in 2013, and imaging in the I-filter
started in 2015. Table 1 gives a record of the 199 images of M31 and
77 images of M33.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 68 274 Image log
table3.dat 67 253 Photometric comparison stars
table4.dat 116 1697 Target photometry
table5.dat 438 200 Target notes
table6.dat 110 32 Possible variables
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See also:
II/336 : AAVSO Photometric All Sky Survey (APASS) DR9 (Henden+, 2016)
J/ApJ/836/64 : Luminous variable stars in M31 + M33. IV. (Humphreys+, 2017)
J/ApJ/825/50 : Variable stars in M31 & M33. III. (Gordon+, 2016)
J/AJ/152/62 : Revised LGGS UBVRI of M31 and M33 stars (Massey+, 2016)
J/ApJ/790/48 : Variable stars in M31 & M33. II. LBVs (Humphreys+, 2014)
J/MNRAS/371/1405 : Variables in M33 (Hartman+, 2006)
J/A+A/445/423 : WeCAPP Survey. M31 variables (Fliri+, 2006)
J/AJ/131/2478 : M31 and M33 UBVRI photometry (Massey+, 2006)
J/AJ/115/1894 : EBs and Cepheids in M31A field (Stanek+ 1998)
J/AJ/115/1016 : M 31B eclipsing binaries and Cepheids (Kaluzny+ 1998)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- Gal Galaxy targeted (M31 or M33)
5- 14 A10 "Y:M:D" Date UT date of exposure start
16- 24 F9.3 d MJD Modified Julian Date at exposure start
26- 28 F3.1 arcsec Seeing [2.6/6.5] Full Width at Half Maximum (FWHM) of
Point-Spread-Function (PSF) (approximate
seeing)
30 A1 --- Flt [BVRI] Johnson-Cousins filter (B, V, R, or I)
32- 33 I2 h RAh Hour of Right Ascension (J2000) (1)
35- 36 I2 min RAm Minute of Right Ascension (J2000) (1)
38- 42 F5.2 s RAs Second of Right Ascension (J2000) (1)
44 A1 --- DE- Sign of the Declination (J2000) (1)
46- 47 I2 deg DEd Degree of Declination (J2000) (1)
49- 50 I2 arcmin DEm Arcminute of Declination (J2000) (1)
52- 55 F4.1 arcsec DEs Arcsecond of Declination (J2000) (1)
57- 61 F5.1 deg Rot [150.8/184.6] Field rotation (2)
63- 66 F4.1 mag Faint [17/19.6] Estimate of faint limit (3)
68 A1 --- f_Faint [d] Flag on Faint for 2017 May images (4)
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Note (1): Image center.
Note (2): Orientation of ascending row axis measured east of north in
degrees. The rotation of the images changed year to year as a result of
wear on the adapter holding the camera to the telescope.
Note (3): A rough completeness limit estimated from peak of the magnitude
frequency distribution for the image. It may be possible to measure some
stars as much as 0.5-1.0mag fainter on the image.
Note (4): Images taken on MJD 57887.404, 57888.390, and 57888.406 were taken
under twilight conditions with a bright sky.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 7 F7.4 deg RAdeg Right Ascension in decimal degrees (J2000)
9- 15 F7.4 deg DEdeg Declination in decimal degrees (J2000)
17- 22 F6.3 mag Vmag [10.59/17.1] The V-band magnitude
24- 28 F5.3 mag e_Vmag [0/0.17] The 1σ error in Vmag
30- 34 F5.3 mag B-V [0.06/1.47]? The (B-V) color index
36- 40 F5.3 mag e_B-V [0.014/0.206]? The 1σ error in B-V
42- 43 A2 --- f_B-V [NA] NA flag on (B-V) color index and error
45- 49 F5.3 mag V-R [0.056/1.11]? The (V-R) color index
51- 55 F5.3 mag e_V-R [0/0.47]? The 1σ error in V-R
57- 61 F5.3 mag V-I [0.11/2.13]? The (V-I) color index
63- 67 F5.3 mag e_V-I [0/0.67]? The 1σ error in V-I
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 20 A20 --- LGGS Star designation (JHHMMSS.ss+DDMMSS.sA format)
in the Local Group Galaxy Survey (LGGS)
22- 41 A20 --- Name Name in catalog
43- 50 F8.2 d MJD Modified Julian Date
52 A1 --- l_Vmag [>] Lower limit flag on Vmag
54- 58 F5.2 mag Vmag [13.81/20.41]? Johnson V-band magnitude
60- 63 F4.2 mag e_Vmag ? The 1σ error in Vmag
65- 67 A3 --- n_Vmag Notes for Vmag (1)
69 A1 --- l_Bmag [>] Lower limit flag on Bmag
71- 75 F5.2 mag Bmag [14.32/20.95]? Johnson B-band magnitude
77- 80 F4.2 mag e_Bmag [0.01/0.41]? The 1σ error in Bmag
82- 84 A3 --- n_Bmag Notes for Bmag (1)
86 A1 --- l_Rmag [>] Lower limit flag on Rmag
88- 92 F5.2 mag Rmag [13.35/20.1]? Cousins R-band magnitude
94- 97 F4.2 mag e_Rmag [0.01/0.41]? The 1σ error in Rmag
99-100 A2 --- n_Rmag Notes for Rmag (1)
102 A1 --- l_Imag [>] Lower limit flag on Imag
104-108 F5.2 mag Imag [12.87/19.71]? Cousins I band magnitude
110-113 F4.2 mag e_Imag [0.03/0.28]? The 1σ error in Imag
115-116 A2 --- n_Imag Notes for Imag (1)
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Note (1): Flags after each magnitude note the following:
T = Magnitude not transformed because no valid color at that epoch;
A = Two measurements averaged into the reported value (see Section 2.3
in the paper);
b = Blending may impact the reported magnitude by less than the reported
error;
B = Blending may impact the reported magnitude by more than the reported
error but there is a good chance that the measurement may still be
reliable;
X = Poor image quality renders this measurement unreliable.
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 20 A20 --- LGGS Star designation (JHHMMSS.ss+DDMMSS.sA format)
in the Local Group Galaxy Survey (LGGS)
22- 41 A20 - Name Name in catalog
43-438 A396 - Note Notes
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 22 A22 --- Class Spectral class (B[e]sg=B[e] supergiant,
LBV=Luminous Blue Variable)
24- 43 A20 --- LGGS Star designation (JHHMMSS.ss+DDMMSS.sA format)
in the Local Group Galaxy Survey (LGGS)
45- 57 A13 --- Name Name in catalog
59- 63 F5.2 mag <Vmag> [15.74/19.35] Average V band magnitude
65- 75 A11 --- Var Variability? (likely, or very likely)
77- 80 F4.2 mag VRange [0.08/0.82] V band magnitude range
82- 85 F4.2 --- R2BV [0.42/1] R2 correlation in the BV band pair
87- 90 F4.2 --- e_R2BV [0.04/0.1] Error in R2BV
92- 95 F4.2 --- R2VR [0.63/1] R2 correlation in the VR band pair
97-100 F4.2 --- e_R2VR [0.04/0.11] Error in R2VR
102-105 F4.2 --- R2BR [0.35/0.97]? R2 correlation in the BR band pair
107-110 F4.2 --- e_R2BR [0.04/0.09]? Error in R2BR
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History:
From electronic version of the journal
(End) Prepared by [AAS]; Sylvain Guehenneux [CDS] 09-Nov-2017