HST Star Case Study

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However, are the NIR photometric properties of these > 3σ detections consistent with the photometric properties of the A HST star? 3.4.2 Photometric calibration of the NIR > 3σ detections The V and I magnitudes of the A HST star are measured with aperture photometry on the HST F 555W and F 814W images (see section 3.2.2), namely, mVH ST,A = 20.23 ± 0.12 and m H I ST,A = 19.39 ± 0.26 mag, respectively. Conversely, using aperture photometry for measuring the magnitudes of the NIR > 3σ detections is not possible in this case, since their stellar profiles are not fully recovered. Alternatively, their J , H , and K S magnitudes can be estimated by taking the ratio of the added NIR peak fluxes of the two guide stars (i.e. G.S.1 and G.S.2) to the peak fluxes of the…show more content…
magnitudes derived in section 3.3.1, F and G.S. G.S.1J ,H ,K S J ,H ,K S F represent the NIR peak fluxes of G.S.1 and G.S.2, respectively, and F repre- G.S.2 >3σ sents the NIR peak fluxes of the > 3σ detections. K S The resulting J , H , and K S magnitudes of the > 3σ detections are m = 18.15 ± 0.37 >3σ H J mag, m = 18.51 ± 0.36, and m = 18.96 ± 0.36, respectively, while their uncertainties >3σ >3σare calculated as
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