M31-004526.62 (J004526.62+415006.3)

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Target Notes

Classification: LBV

Not resolved from J004526.58+415005.8 less than one arcsecond N. According to LGGS the unresolved neighbor has odd colors with comparable brightness in BRI but contributes -0.04 mag in V.

Photometry Table

MJD	V	*	Image	B	*	Image	R	*	Images	I	*	Images
56537.24	16.34± 0.05	b		--	-	-	15.99± 0.06	B		--	-	-
56593.10	16.32± 0.03	b		--	-	-	16.00± 0.04	B		--	-	-
56951.07	16.62± 0.05	b		16.86± 0.04	B		16.17± 0.06	B		--	-	-
56982.20	16.51± 0.05	b		16.88± 0.05	B		--	-	-	--	-	-
57036.13	16.47± 0.06	b		16.83± 0.04	B		--	-	-	--	-	-
57309.14	16.41± 0.05	b		16.75± 0.03	B		16.05± 0.06	B		--	-	-
57340.21	16.47± 0.03	b		--	-	-	--	-	-	15.86± 0.07	B
57633.35	16.74± 0.05	b		17.06± 0.05	B		16.38± 0.05	B		--	-	-
57638.29	16.78± 0.04	b		--	-	-	--	-	-	16.19± 0.05	B
57958.32	17.51± 0.07	b		17.77± 0.07	B		--	-	-	17.04± 0.07	B
57963.28	17.54± 0.06	b		17.89± 0.08	B		17.17± 0.06	B		--	-	-
58045.07	17.48± 0.05	b		17.83± 0.07	B		17.14± 0.06	B		--	-	-
58067.12	17.52± 0.09	b		--	-	-	--	-	-	17.01± 0.07	B
58098.12	17.56± 0.07	b		17.80± 0.06	B		--	-	-	--	-	-
58312.32	17.51± 0.05	b		17.76± 0.05	B		17.18± 0.06	B		--	-	-
58316.28	17.49± 0.04	b		--	-	-	--	-	-	16.98± 0.06	B
58341.25	17.61± 0.06	b		17.92± 0.08	B		--	-	-	--	-	-
58366.14	17.51± 0.05	b		17.71± 0.04	B		--	-	-	--	-	-
58372.12	17.49± 0.09	b		--	-	-	--	-	-	17.07± 0.06	B
58403.12	17.45± 0.04	b		--	-	-	17.22± 0.06	B		--	-	-
58420.03	17.40± 0.05	b		17.72± 0.07	B		--	-	-	--	-	-
58436.02	17.45± 0.06	b		17.55± 0.04	B		17.24± 0.06	B		--	-	-
58671.30	17.11± 0.04	b		17.39± 0.05	B		--	-	-	--	-	-
58672.32	16.96± 0.05	b		--	-	-	16.59± 0.05	B		16.39± 0.07	B
58695.30	16.93± 0.05	Ab		17.21± 0.05	B		16.65± 0.04	B		16.46± 0.05	B
58696.28	16.94± 0.04	b		--	-	-	16.65± 0.05	B		16.41± 0.06	B
58757.08	16.91± 0.04	b		--	-	-	16.57± 0.04	B		--	-	-
58784.04	16.91± 0.04	b		17.18± 0.04	B		--	-	-	--	-	-
58812.10	16.92± 0.03	b		--	-	-	16.60± 0.05	B		--	-	-
58836.18	16.86± 0.03	b		--	-	-	--	-	-	16.30± 0.04	B
59001.39	16.94± 0.05	b		--	-	-	16.50± 0.04	B		--	-	-
59059.31	16.97± 0.03	b		17.25± 0.04	B		16.65± 0.04	B		--	-	-
59077.22	16.96± 0.06	b		--	-	-	16.61± 0.05	B		--	-	-
59081.22	16.89± 0.04	b		--	-	-	--	-	-	16.35± 0.05	B
59131.05	16.88± 0.04	b		17.21± 0.06	B		--	-	-	--	-	-
59136.11	16.82± 0.03	b		17.19± 0.10	B		16.50± 0.03	B		--	-	-
59166.07	16.79± 0.03	b		--	-	-	--	-	-	16.23± 0.06	B
59166.25	16.82± 0.03	b		--	-	-	--	-	-	16.24± 0.05	B
59376.36	16.83± 0.05	b		17.17± 0.06	B		--	-	-	--	-	-
59380.36	16.70± 0.03	b		--	-	-	16.41± 0.04	B		--	-	-
59409.38	16.64± 0.04	b		--	-	-	16.31± 0.04	B		--	-	-
59415.34	16.63± 0.04	b		16.95± 0.04	B		--	-	-	--	-	-
59442.30	16.55± 0.04	Ab		16.90± 0.04	B		16.20± 0.04	B		15.91± 0.05	AB
59467.14	16.53± 0.04	b		--	-	-	16.19± 0.04	B		--	-	-
59485.12	16.50± 0.03	b		16.95± 0.10	B		--	-	-	--	-	-
59522.07	16.52± 0.04	b		16.92± 0.04	B		--	-	-	--	-	-
59525.06	16.48± 0.03	b		--	-	-	--	-	-	15.84± 0.05	B
59546.07	16.56± 0.03	b		--	-	-	--	-	-	15.90± 0.05	B
59551.04	16.53± 0.03	b		16.93± 0.03	B		16.19± 0.04	B		--	-	-
59583.07	16.61± 0.04	b		--	-	-	16.26± 0.05	B		--	-	-
59753.35	16.66± 0.08	Ab		16.90± 0.07	B		16.29± 0.08	B		--	-	-
59816.21	16.51± 0.03	Tb		--	-	-	--	-	-	--	-	-
59823.21	16.57± 0.04	b		--	-	-	16.23± 0.04	B		--	-	-
59848.13	16.60± 0.03	b		--	-	-	--	-	-	16.01± 0.05	B
59851.07	16.72± 0.09	b		--	-	-	16.30± 0.05	B		16.01± 0.07	B
59879.07	16.69± 0.04	b		16.98± 0.04	B		--	-	-	--	-	-
59903.15	16.86± 0.03	b		17.16± 0.04	B		16.49± 0.03	B		--	-	-
59905.22	16.88± 0.04	b		17.21± 0.06	B		--	-	-	16.24± 0.06	B
60147.34	17.69± 0.10	b		--	-	-	17.35± 0.05	B		--	-	-
60172.31	17.88± 0.04	Ab		18.11± 0.04	B		17.47± 0.05	B		17.26± 0.05	AB
60202.15	17.93± 0.10	Ab		18.14± 0.10	AB		17.62± 0.12	AB		--	-	-
60251.07	17.95± 0.06	Ab		18.18± 0.08	B		--	-	-	17.52± 0.06	B
60290.08	17.98± 0.07	b		--	-	-	--	-	-	17.39± 0.07	B
60292.13	18.00± 0.04	b		18.21± 0.05	B		--	-	-	--	-	-
60469.37	18.22± 0.07	b		18.20± 0.06	B		--	-	-	--	-	-
60498.30	17.99± 0.07	b		--	-	-	17.62± 0.04	B		--	-	-
60506.31	18.05± 0.07	b		18.28± 0.08	B		--	-	-	--	-	-
60529.25	18.07± 0.07	b		--	-	-	17.77± 0.05	B		17.74± 0.07	B
60533.32	18.05± 0.04	b		18.16± 0.04	B		--	-	-	--	-	-
60555.18	18.05± 0.06	b		18.24± 0.08	B		17.72± 0.07	B		--	-	-
60564.20	17.93± 0.05	b		--	-	-	17.64± 0.04	B		--	-	-
60594.05	18.06± 0.05	b		--	-	-	--	-	-	17.52± 0.06	B
60595.05	18.05± 0.08	b		18.16± 0.08	B		17.64± 0.07	B		--	-	-
60651.09	18.03± 0.05	b		18.18± 0.06	B		17.71± 0.05	B		--	-	-

Plots of Brightness and Color

Variability

It is very likely that this star is variable.

Correlation factors between bands

If the brightness variation is true variability then there should be a correlation between brightness changes recorded in different filter bands. The following table are the R-squared linear correlation factors calculated for the pairs of bands. The number in parentheses next to the R-squared value is the number of elements used to calculate the correlation factor. The number in square brackets next to the band is the range of magnitudes measured.

	V [1.90 mag]	B [1.53 mag]	R [1.78 mag]
B [1.53 mag]	0.99 (40)
R [1.78 mag]	0.99 (38)	0.97 (19)
I [1.90 mag]	0.99 (24)	0.97 (6)	0.99 (7)

Magnitude-Magnitude Plots

The plots below are provided to check the values in the table above and also to show any non-linear correlations

I & R Statistics

Welch & Stetson (1993, AJ, 105, 1813) present a method for varible star detection in CCD images from automated surveys. Data from two bands are compared and two statistics are calculated: R and I.

The I-statistic has an expectation value of zero for stars that are NOT variable. A larger non-zero I-value indicates a higher likelihood that the star is variable. The R statistic indicates how the color of the star changes as the variable grows brighter with R = 1.0 being no change in color.

R and I values have only been calculated if there are more than four (4) matched measurements of brightness in each band.

	V (I|R)	B (I|R)	R (I|R)
B (I|R)	111.03 | 0.82
R (I|R)	118.95 | 0.94	89.96 | 0.67
I (I|R)	106.89 | 1.04	101.51 | 0.92	121.73 | 1.16