Multi-band Photometric Study of the Variable Star BN Tri

Abstract

: Using the 43.18 cm wide-field telescope at Xinjiang Astronomical Observatory, we carried out BVR three-band photometric observations of the variable star BN Tri. The data were reduced and the light curves were analyzed with the software MaxIm DL 6. The light curves in the g, r, and i bands were subjected to three-frequency sinusoidal fitting using the Period04 software, yielding residuals of 0.00848, 0.00700, and 0.00673, respectively, indicating a good fitting quality. The fundamental frequency F1 is measured to be about 13.47 d⁻¹, corresponding to a period of approximately 0.074 days, which is in good agreement with the period of 0.070 days given in the GCVS5 catalog. This consistency supports the reliability of our data and confirms that BN Tri is a short-period pulsating variable star of δ Scuti type. Meanwhile, the secondary frequencies F2 and F3 exhibit slight shifts between the r and i bands, with their amplitudes showing a decreasing trend from the r band to the i band, and significant phase differences are observed among the bands. These features reflect differences in the vertical propagation of distinct pulsation modes. The zero-point values in the g, r, and i bands are 0.268, −0.413, and −0.208, respectively, indicating an asymmetric band-to-band distribution of the mean spectral energy. In summary, the measured period is in good agreement with the GCVS5 value (0.070 days), with a relative deviation of about 5.7%, which is within the allowable range of observational errors, thus validating the effectiveness of the present observational data.