Time delays in PG 1115+080: new estimates

Authors


E-mail: vakulik@astron.kharkov.ua

ABSTRACT

We report new estimates of the time delays in the quadruple gravitationally lensed quasar PG 1115+080, obtained from the monitoring data in filter R with the 1.5-m telescope at the Maidanak Mountain (Uzbekistan, Central Asia) in 2004–2006. The time delays are 16.4 d between images C and B and 12 d between C and A1+A2, with image C leading for both pairs. The only known estimates of the time delays in PG 1115 are those based on observations by Schechter et al. –23.7 and 9.4 d between images C and B, and C and A1+A2, respectively, – and as revised by Barkana –25 and 13.3 d for the same image components, but with the use of another method. The new values of time delays in PG 1115+080 may be expected to provide larger estimates of the Hubble constant, thus decreasing a diversity between the H0 estimates taken from gravitationally lensed quasars and those taken from other methods.

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