M31-004424.21 (J004424.21+412116.0)

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Target Notes

Classification: YSG

No blend concerns

Photometry Table

MJD	V	*	Image	B	*	Image	R	*	Images	I	*	Images
56142.33	16.59± 0.05	T		--	-	-	--	-	-	--	-	-
56267.14	--	-	-	--	-	-	16.06± 0.05	T		--	-	-
56490.38	16.68± 0.04	T		--	-	-	--	-	-	--	-	-
56536.26	16.69± 0.05	-		--	-	-	16.13± 0.06	-		--	-	-
56537.20	16.66± 0.05	-		17.54± 0.07	-		--	-	-	--	-	-
56915.14	16.68± 0.03	A		17.57± 0.05	A		16.11± 0.04	A		--	-	-
57227.33	16.70± 0.04	A		17.57± 0.04	A		16.12± 0.04	A		--	-	-
57310.09	16.60± 0.03	A		--	-	-	--	-	-	15.55± 0.06	A
57633.30	16.80± 0.05	A		17.72± 0.06	A		16.19± 0.05	A		--	-	-
57635.35	16.75± 0.05	-		--	-	-	--	-	-	15.64± 0.06	-
57638.27	16.84± 0.05	-		--	-	-	--	-	-	15.75± 0.04	-
57928.34	16.55± 0.04	A		17.44± 0.05	A		16.00± 0.05	A		15.47± 0.07	A
57958.26	16.50± 0.06	-		17.37± 0.07	-		--	-	-	15.44± 0.06	-
57963.26	16.50± 0.06	-		17.37± 0.07	-		--	-	-	--	-	-
57988.22	16.52± 0.07	-		17.37± 0.07	-		--	-	-	15.42± 0.06	-
58035.03	16.61± 0.04	-		--	-	-	16.04± 0.04	-		--	-	-
58043.05	16.59± 0.05	-		17.50± 0.06	-		16.01± 0.04	-		--	-	-
58045.05	16.59± 0.05	-		--	-	-	--	-	-	15.47± 0.06	-
58067.10	16.59± 0.04	-		--	-	-	--	-	-	15.48± 0.06	-
58073.09	16.58± 0.06	-		17.49± 0.07	-		--	-	-	--	-	-
58077.08	16.56± 0.07	-		--	-	-	--	-	-	15.47± 0.07	-
58098.07	16.54± 0.06	-		17.43± 0.07	-		--	-	-	--	-	-
58103.08	16.56± 0.05	-		--	-	-	--	-	-	15.47± 0.07	-
58312.26	16.57± 0.06	-		17.46± 0.07	-		15.99± 0.06	-		--	-	-
58316.24	16.59± 0.06	-		--	-	-	--	-	-	15.45± 0.06	-
58339.26	16.54± 0.07	-		--	-	-	--	-	-	15.45± 0.07	-
58342.26	16.57± 0.04	-		17.45± 0.07	-		--	-	-	--	-	-
58366.11	16.55± 0.04	-		17.50± 0.06	-		--	-	-	--	-	-
58375.09	16.57± 0.05	-		--	-	-	15.98± 0.04	-		--	-	-
58403.06	16.58± 0.03	-		--	-	-	--	-	-	15.46± 0.05	-
58420.01	16.60± 0.06	-		17.47± 0.08	-		--	-	-	--	-	-
58433.09	16.58± 0.06	-		17.52± 0.06	-		16.02± 0.06	-		--	-	-
58436.04	16.59± 0.04	-		17.49± 0.06	-		16.00± 0.04	-		--	-	-
58671.29	16.61± 0.07	-		17.61± 0.06	-		--	-	-	--	-	-
58673.29	16.63± 0.08	-		--	-	-	16.04± 0.07	-		15.49± 0.08	-
58696.30	16.64± 0.07	-		17.65± 0.07	-		16.03± 0.08	-		--	-	-
58750.07	16.63± 0.07	-		17.65± 0.07	-		--	-	-	--	-	-
58779.05	16.61± 0.06	-		--	-	-	16.03± 0.03	-		--	-	-
58812.07	16.60± 0.08	-		--	-	-	15.99± 0.08	-		--	-	-
59000.39	16.54± 0.07	-		--	-	-	15.98± 0.10	-		--	-	-
59055.31	16.60± 0.07	-		--	-	-	16.02± 0.08	-		--	-	-
59077.20	16.61± 0.07	-		17.58± 0.07	-		16.02± 0.07	-		15.48± 0.10	-
59131.09	16.59± 0.07	-		--	-	-	16.00± 0.07	-		--	-	-
59166.12	16.63± 0.07	-		--	-	-	--	-	-	15.49± 0.09	-
59194.11	16.61± 0.07	-		17.61± 0.07	-		--	-	-	--	-	-
59376.35	16.56± 0.07	-		17.56± 0.07	-		--	-	-	--	-	-
59409.37	16.57± 0.07	-		--	-	-	15.99± 0.07	-		--	-	-
59441.26	16.57± 0.07	-		17.55± 0.08	-		--	-	-	15.45± 0.09	-
59467.11	16.49± 0.07	-		--	-	-	15.87± 0.06	-		--	-	-
59522.04	16.52± 0.07	-		17.50± 0.07	-		--	-	-	15.44± 0.11	-
59546.05	16.56± 0.07	-		--	-	-	15.99± 0.07	-		--	-	-
59583.10	16.59± 0.07	-		17.58± 0.07	-		--	-	-	--	-	-
59739.36	16.48± 0.07	-		17.37± 0.07	-		15.92± 0.07	-		--	-	-
59816.14	16.64± 0.06	-		--	-	-	--	-	-	15.52± 0.07	-
59851.09	16.65± 0.07	-		17.72± 0.07	-		16.06± 0.07	-		--	-	-
59879.03	16.69± 0.07	-		--	-	-	--	-	-	15.52± 0.06	-
59905.07	16.68± 0.07	-		17.70± 0.07	-		16.09± 0.07	-		--	-	-
60147.26	16.66± 0.07	A		17.63± 0.07	-		16.05± 0.07	-		--	-	-
60172.19	16.70± 0.07	A		17.73± 0.07	-		16.07± 0.06	-		15.54± 0.08	A
60201.09	16.68± 0.07	-		--	-	-	16.02± 0.07	-		--	-	-
60202.10	16.66± 0.06	-		17.63± 0.07	-		--	-	-	--	-	-
60251.02	16.46± 0.07	A		17.41± 0.07	-		--	-	-	15.35± 0.07	-
60290.08	16.45± 0.07	A		--	-	-	15.90± 0.07	-		15.40± 0.09	-
60469.36	16.61± 0.07	A		17.58± 0.07	-		16.01± 0.08	-		--	-	-
60504.32	16.56± 0.07	A		17.53± 0.08	-		15.94± 0.06	-		--	-	-
60529.23	16.52± 0.07	-		--	-	-	--	-	-	15.42± 0.06	-
60533.25	16.52± 0.07	T		--	-	-	--	-	-	--	-	-
60555.14	16.49± 0.06	A		17.37± 0.06	-		15.92± 0.06	A		15.40± 0.09	-
60587.10	16.50± 0.06	-		--	-	-	--	-	-	15.43± 0.06	-
60594.07	16.52± 0.07	-		17.43± 0.07	-		15.92± 0.07	-		--	-	-
60649.08	16.59± 0.07	-		17.52± 0.07	-		16.00± 0.07	-		--	-	-
60651.11	16.56± 0.06	-		--	-	-	--	-	-	15.47± 0.09	-

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 [0.40 mag]	B [0.37 mag]	R [0.33 mag]
B [0.37 mag]	0.74 (38)
R [0.33 mag]	0.89 (34)	0.60 (20)
I [0.40 mag]	0.88 (27)	0.63 (9)	0.98 (6)

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)	1.63 | 1.28
R (I|R)	1.53 | 1.12	2.47 | 0.05
I (I|R)	2.09 | 1.20	0.87 | 2.75	0.61 | 1.58