obsid   target                  start time      int time    inst    ccd     grat    drop rate(%)
-----------------------------------------------------------------------------------------------------------
7783	SDSS_J1335+3533     	70:55911.078		23.9	ACIS-S	S4		NONE	34.4
9699	Cas_A[S3,-120,-     	84:42812.863		 3.1	ACIS-S	S4		NONE	8.4
9698	Cas_A[I3,-120,-     	84:47299.404		 2.1	ACIS-I	I4		NONE	3.6