Greetings,
Z Tau is in the list of LPVs of the LPV Double Trouble Campaign. These are stars that have close companions.
MAOPhot uses the PSF (point spread function) Photometry exclusively to overcome problems with measuring targets with close companions. (See GitHub - petefleurant/PSF-Photometry: Two Color Photometry using Photutils.psf (model fitting photometry) )
Images recently taken by the Mittelman ATMoB Observatory (MAO) were processed and then analyzed by MAOPhot which uses Python Astropy Photutils.
The following are results for V-R color Photometry (AAVSO Comparison Star Chart ID X39596AYP) :
Check Star Estimates using check star: 118 (V: 11.810) (R: 11.666)
V* Ave: 11.814 R* Ave: 11.661
V* Std: 0.015 R* Std: 0.026
Variable Star Estimates of Var: Z Tau
V* Ave: 15.254 R* Ave: 13.060
V* Std: 0.015 R* Std: 0.026
Note using AAVSO’s VPhot with same sequence 127, 130, 136, 141, 144
VPhot resulted in check star estimates of
V* Ave: 11.803 R* Ave: 11.671
V* Std: 0.015 R* Std: 0.013
The PSF used MAOPhot was a Circular Gaussian model of FWHM=3.0.
The report follows:
#TYPE=Extended
#OBSCODE=FPIA
#SOFTWARE=Self-developed; MAOPhot 1.1.6 using Photutils
#DELIM=,
#DATE=JD
#OBSTYPE=CCD
#NAME,DATE,MAG,MERR,FILT,TRANS,MTYPE,CNAME,CMAG,KNAME,KMAG,AMASS,GROUP,CHART,NOTES
Z Tau,2460953.79293,15.253,0.013,V,YES,STD,ENSEMBLE,na,118,11.813,1.371,na,X39596AYP,Mittelman ATMoB Observatory|KMAGINS=-9.128|KMAGSTD=11.813|KREFMAG=11.81|Tvr=1.401|TvrErr=0.024|VMAGINS=-5.782
Z Tau,2460953.79813,13.062,0.023,R,YES,STD,ENSEMBLE,na,118,11.662,1.371,na,X39596AYP,Mittelman ATMoB Observatory|KMAGINS=-9.086|KMAGSTD=11.662|KREFMAG=11.666|Tr_vr=-0.245|Tr_vrErr=0.01|VMAGINS=-7.189
I welcome comments, suggestions, and questions.
Pierre Fleurant
FPIA