New variable stars in the globular cluster NGC 288

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We report discovery of 3 new faint variables in the globular cluster NGC 288: 2 SX Phe stars and 1 contact binary. Both SX Phe variables are blue stragglers. The contact binary is located below cluster turnoff, slightly to the red of the main sequence. New photometry of 6 previously known variables is also presented. We note that 26 out of a total 43 SX Phe stars identified recently in ω Cen and NGC 288 exhibit V-band light curves with full amplitudes smaller than 0.10 mag. The sample of known SX Phe stars is likely to be significantly incomplete in regard to the low amplitude variables.