We report on the analysis of a microlensing event OGLE-2014-BLG-1722 that showed two distinct short term anomalies .
The best fit model to the observed light curves shows that the two anomalies are explained with two planetary mass ratio companions to the primary lens .
Although a binary source model is also able to explain the second anomaly , it is marginally ruled out by 3.1 \sigma .
The 2-planet model indicates that the first anomaly was caused by planet “ b ” with a mass ratio of q = ( 4.5 _ { -0.6 } ^ { +0.7 } ) \times 10 ^ { -4 } and projected separation in unit of the Einstein radius , s = 0.753 \pm 0.004 .
The second anomaly reveals planet “ c ” with a mass ratio of q _ { 2 } = ( 7.0 _ { -1.7 } ^ { +2.3 } ) \times 10 ^ { -4 } with \Delta \chi ^ { 2 } \sim 170 compared to the single planet model .
Its separation has two degenerated solutions : the separation of planet c is s _ { 2 } = 0.84 \pm 0.03 and s _ { 2 } = 1.37 \pm 0.04 for the close and wide models , respectively .
Unfortunately , this event dose not show clear finite source and microlensing parallax effects , thus we estimated the physical parameters of the lens system from Bayesian analysis .
This gives that the masses of planet b and c are m _ { b } = 56 _ { -33 } ^ { +51 } M _ { \oplus } and m _ { c } = 85 _ { -51 } ^ { +86 } M _ { \oplus } , respectively , and they orbit a late type star with a mass of M _ { host } = 0.40 _ { -0.24 } ^ { +0.36 } M _ { \odot } located at D _ { L } = 6.4 _ { -1.8 } ^ { +1.3 } kpc from us .
The projected distance between the host and planets are r _ { \perp, b } = 1.5 \pm 0.6 AU for planet b , and r _ { \perp, c } = 1.7 _ { -0.6 } ^ { +0.7 } AU and r _ { \perp, c } = 2.7 _ { -1.0 } ^ { +1.1 } AU for close and wide models of planet c. If the 2-planet model is true , then this is the third multiple planet system detected by using the microlensing method , and the first multiple planet system detected in the low magnification events , which are dominant in the microlensing survey data .
The occurrence rate of multiple cold gas giant systems is estimated using the two such detections and a simple extrapolation of the survey sensitivity of 6 year MOA microlensing survey ( 88 ) combined with the 4 year \mu FUN detection efficiency ( 40 ) .
It is estimated that 6 \pm 2 \% of stars host two cold giant planets .