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determining the chemical composition of stars is one of the primary goals of astrophysics .
such investigations help us to better understand the chemical enrichment of the galaxy and to make some assumptions about the mechanisms involved in element evolution in the interstellar medium , and in stellar atmospheres in particular @xcite . while studying the sun , the problem of the abundances of certain atoms necessitated a model to explain this .
it was finally explained with the introduction of the pp- and cno- cycles in the interior of the sun .
but this was not enough to explain the presence of large amounts of helium .
the next step in studying the evolution of elements was the introduction of nucleosynthesis theory .
modern scientific understanding is that chemical elements were formed as a result of the processes occurring in stars , leading to evolutionary changes of their physical conditions .
therefore , the problem of nuclide formation is also closely related to the issue of the evolution of stars and planetary system .
recently jenkins et al .
@xcite announced the discovery of a low - mass planet orbiting the super hd77338 as part of our ongoing calan - hertfordshire extrasolar planet search @xcite .
the best - fit planet solution has an orbital period of 5.7361 @xmath4 0.0015 days and with a radial velocity semi - amplitude of only 5.96@xmath41.74  ms@xmath5 , giving a minimum mass of @xmath6  m@xmath7 .
the best - fit eccentricity from this solution is 0.09@xmath8 , and is in the agreement with results of a bayesian analysis and a periodogram analysis .    according to modern theory ,
the formation of the nucleus of chemical elements from carbon to iron is the result of thermonuclear reactions involving he , c , o , ne and si in stars .
after the depletion of hydrogen reserves , a star s core starts running a 3@xmath9 reaction , where it produces a number of elements as a result of the following transformations : @xmath10 , @xmath11 , @xmath12 .
+ after reaching a specific threshold temperature , carbon begins fusing with the formation of ne , na and mg :    @xmath13 , + @xmath14 , + @xmath15 .
+ aluminum can then be produced by : @xmath16 .
+ the combustion reaction of oxygen is a dual - channel process and causes the presence of al , s , p , si and mg . one of the channels is : + @xmath17 , + @xmath18 , + @xmath19 , + with continuous temperature growth , silicon burning is initiated .
this process is described by a number of reactions . as a result
we can receive , for example , ar , ni , s , etc .
@xmath20 , after two @xmath21 decays , turns into @xmath22 .
it is the final stage of the fusion of nuclides in massive stars , which forms the nucleus of the iron group .
+ the production of heavy elements is provided by other mechanisms .
they are called s- and r- processes .    * s - process or slow neutron capture : formation of heavier nuclei by lighter nuclei through successive neutron capture .
the original element in the s - process is @xmath22 .
the reaction chain ends with @xmath23 .
it is thought that s - processes occur mostly in stars on the asymptotic giant branch .
for the s - process to run , an important condition is the ability to produce neutrons .
the main neutron source reactions are : @xmath24 , @xmath25 .
example of s - process reactions are : @xmath26    elements heavier than h and he are usually called metals in astrophysics . their concentration is significantly less , relative to hydrogen and helium , but they are the source of thousands of spectral lines originating from a star s atmosphere .
the abundance of iron depends on a stars age and on its position in the galaxy @xcite .
metal - rich stars are also known to be rich in orbiting giant exoplanets .
high metallicity appears to be a major ingredient in the formation of planets through core accretion @xcite . +
hd 77338 is one of the most metal - rich stars in the sample of @xcite and in the local solar neighborhood in general .
its spectral type is given as k0iv in the hipparcos main catalogue @xcite .
however , is not a subgiant , as labeled in hipparcos @xcite , its mass and radius are smaller than the sun s : m = 0.93 @xmath27 0.05 m@xmath28 , r = 0.88 @xmath27 0.04 r@xmath28 .
a parallax of 24.54 @xmath27 1.06 mas for hd 77338 means the star is located at a distance of 40.75 @xmath4 1.76 pc .
its effective temperature and surface gravity were found @xmath29 = 5370 @xmath27 80 k , log@xmath30 = 4.52 @xmath27 0.06 @xcite .
more stellar parameters for hd 77338 and detailed information about its planetary system are in @xcite .
using the simbad database one can find information on the previous assessments of abundances in the atmosphere of hd 77338 ( see table  [ tab1 ] ) . in most cases
the authors only determine the metallicity of the star , i.e. the iron abundance . in turn , we recomputed the abundances of many elements which show significant absorption lines in the observed spectrum of .
.simbad s list of previous assessments of abundances in the atmosphere of hd 77338 [ cols="^,^,^,^,^,^",options="header " , ]     in table  [ tab2 ] we present our results for 12 different ionic species .
we compare our abundances with the solar values , obtained using a model atmosphere of 5777/4.44/0.00 .
they are in good agreement with each other .
[ fig2 ] and fig .
[ fig3 ] show the line profiles of cr and mg calculated using a @xmath31 = 0.75 km / s .    in fig .
[ fig4 ] we show the dependence of [ x / h ] on atomic number of each element for every iteration .
the presence of errors can be explained by the presence of noise in the selected spectral lines , along with only having a small number of lines to work with for some elements . in fig .
[ fig5 ] we present the dependence of [ x / fe ] for the final iteration , where different elements are shown using different plotting shapes depending on their mechanism of formation .
we determined abundances for 12 ionic species in the atmosphere of the sun and the metal - rich exoplanet host star hd 77338 .
our values for the solar abundances are in good agreement with results from previous authors , proving the validity of our method .
we used the solar spectrum as a reference to select the proper list of absorption lines to be used later in the analysis of the spectrum .
our [ x / h ] correlates well with the condensation temperature of the ions ( @xmath32 ) , see discussion in @xcite .
this may indicate the presence of a common shell ( in the past ) and can be an additional criterion for the existence of a planetary system around metal - rich stars .
we also computed @xmath33 for both stars .
it is worth noting that we determined all parameters in the framework of a fully self - consistent approach ( see @xcite for more details ) . in general , lines of mn
, cu can not be used to obtain @xmath33 because these lines usually have several close components , but in our case the parameter @xmath34 was used to adjust theoretical profiles to get the proper fits to the observed special features .
we believe that fits to fe i lines provide reasonable measures of the rotational velocity .
our results show that the abundances of most elements in the atmosphere can be described well by the overall metallicity . however , we found an overabundance of some of the iron peak elements ( e.g. mn , cu ) .
interestingly , cu is an element formed through the s - process and its abundance follows that of fe , whereas zn and elements formed through the p - process , e.g. ni ( see http://www.mao.kiev.ua/staff/yp/txt/prs.png ) , show a noticeable overabundance compared to iron
. it would be interesting to compare these results for with other metal rich stars to see if this is a common trend for super metal - rich stars .
we plan to investigate this issue in a following paper ( ivanyuk et al .
2013 , in preparation ) .
jsj acknowledges the support of the basal - cata grant .
yp s work has been supported by an fp7 postagbingalaxies grant ( no .
269193 ; international research staff exchange scheme ) .
authors thank the compilers of the international databases used in our study : simbad ( france , strasbourg ) , vald ( austria , vienna ) , and the authors of the atlas of the spectrum of the sun as a star .
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abundances of fe , si , ni , ti , na , mg , cu , zn , mn , cr and ca in the atmosphere of the k - dwarf hd 77338 are determined and discussed . 
 hd 77338 hosts a hot uranus - like planet and is currently the most metal - rich single star to host any planet . 
 determination of abundances was carried out in the framework of a self - consistent approach developed by pavlenko et al . 
 ( 2012 ) . 
 abundances were computed iteratively by the program abel8 , and the process converged after 4 iterations . 
 we find that most elements follow the iron abundance , however some of the iron peak elements are found to be over - abundant in this star . 
 + * key words : * stars : abundances , stars : atmospheres , stars : individual ( hd 77338 ) , line : profiles .    
 @xmath0taras shevchenko national university of kyiv , glushkova ave . , 4 , 03127 , kyiv , ukraine + @xmath1main astronomical observatory of the nas of ukraine , 27 akademika zabolotnoho st . 
 , 03680 kyiv , ukraine + @xmath2centre for astrophysics research , university of hertfordshire , college lane , hatfield , hertfordshire al10 9ab , uk + @xmath3departamento de astronoma , universidad de chile , camino el observatorio 1515 , las condes , santiago , chile + nondanone@gmail.com