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Paper text:
dynamical studies of the galilean satellites require the series of accurate positional observations .
an analysis of the light curves of satellites obtained during the mutual phenomena allows us to get high - precise astrometric data - differences of topocentric ( in the case of mutual occultations ) or heliocentric ( for mutual eclipses ) coordinates of two satellites involved in the phenomenon .
mutual phenomena in the system of galilean satellites of jupiter are repeated with a period of six years and nine months .
the aim of this work is providing observational data for further analysis .
pulkovo observatory was taking part in the previous international campaigns of mutual phenomena observations in 1995 , 1997 , 2003 and 2009  ( @xcite ) .
pulkovo observatory had collect about of ten percents of all world observations during the campaign of 2003  ( @xcite ) .
recent set of phenomena was available for observations at pulkovo ( 084 ) and at mountain station near kislovodsk ( c20 ) from october 2014 to august 2015 .
jupiter s altitude reached to 45 degrees in the meridian .
ephemeris of mutual phenomena were provided by celestial mechanics department of sai msu and presented at the ephemeris server multi - sat  ( @xcite ) .
.telescopes , cameras and observers . [ cols="<,<,<,<,<",options="header " , ]
observations were carried out with three pulkovo telescopes ( 26-inch refractor , normal astrograph , astrograph za-320 ) and the mtm-500 m telescope of the pulkovo mountain station near kislovodsk ( see table  [ tab1 ] ) .
the observations were performed according to the recommendations given in emelyanov s paper  ( @xcite ) .
observations began in advance before the start of phenomenon and continued for up to the duration time after it s end .
the exposure time was varied from 0.1  s to 1  s , depending on weather conditions and the magnitudes of satellites .
no filter was used .
these ccd images were analyzed and integrated fluxes were calculated for satellite images at the central moment of each frame .
dark current and flat fields were taken into account by the standard way . as a result
, we obtained the ratio of satellite light flux and reference object or the difference between magnitudes of the satellite and the reference object .
we chose the satellite , which did not involved in a phenomenon , or a background star as a reference object . to correct the background gradient due to planet s scattered light we calculated the background intensities using a linear model according to expression @xmath0 .
the parameters @xmath1 , @xmath2 and @xmath3 were determined by the least squares method using intensity value of the pixels ( @xmath4 ) within the ring - shaped area around the image of the satellite . whenever possible , the jupiter was taken out of the field of view of the camera to minimize errors in determining the background .
the least radius of aperture was selected .
in a total , we performed 73 observations of 37 mutual phenomena .
fifty - series of ccd frames of suitable quality and light curves were obtained . some examples of light curves
are shown in fig .
the values of magnitude differences were approximated by a quadratic polynomials to estimate preliminary values of photometric precision .
the standard deviations of determining the magnitudes are ranged from 0.02 to 0.19 mag .
the obtained light curves are available at the pulkovo database http://puldb.ru / photometry / phemu2014 - 2015/.
this work was supported by russian foundation for basic research ( project no .
15 - 02 - 03025 ) .
emelyanov n. v. , andreev m. v. , berezhnoi a. a. et al astrometric results of observations at russian observatories of mutual occultations and eclipses of jupiter s galilean satellites in 2009 .
research , 45,3 , 264 ( 2011 ) .
we present the results of photometric observations of the mutual phenomena in the system of galilean satellites obtained during 2014 - 2015 . 
 the observations were performed using the 26-inch refractor , normal astrograph , za-320 telescope of the pulkovo observatory ( 084 ) and mtm-500 telescope at pulkovo mountain station at kislovodsk ( c20 ) . 
 we made observations a total of 72 phenomena . 
 we had derived 51 light curves of good and medium quality for 34 events . 
 the rms of determining the brightness is within a range from 0.02 to 0.19 mag , the average rms is 0.06 mag . 
 this work was supported by rfbr grant ( project 15 - 02 - 03025 ) .