Astrochemistry, Astrobiology and Exoplanets

Program: 2021-2022

1. Recycling of organic (carbon containing) matter in the Galaxy
1.1 Possibility of PAH, C60 and other similar species origin under planetary nebulae conditions.
1.2 Possible origin (and/or destruction) of PAH molecules in the aromatization processes under ISM conditions.
1.3 Clumps in planetary nebulae (PN) as important sources of ISM organics processed by joint vacuum ultraviolet (VUV) and corpuscular energetic particles (EP) radiation.
1.4 Possible polymerization of aliphatic hydrocarbons (methane, acetylene etc.) in wind clumps during AGB to PN transition phase and later.
1.5 Possible origin of PAH, HAC, C60 and other such species under conditions of PN clumps when aliphatization processes dominate over aromatization.
1.6 Differentiation of aliphatic and aromatic hydrocarbons in molecular clouds.
1.7 Theoretical investigation of origin of prebiotic molecules (diene hydrocarbons, aminoacids, sugars etc.) under newborn stellar disk conditions followed by the search of their manifestation in available observed spectra.
1.8 Spectral manifestation of organics in AGB and PN depending on C/O ratio and AGB and PN nuclei outflows rates and velocities.
1.9 Survivability of ices under PN conditions.
1.9.1 Gas to solid water in clumps and beyond the non-stationery PDR.
1.9.2 Amorphous to crystalline type of water ice as above.
2. Survivability of complex chemical species in galaxies during their evolution
2.1 Connection between star formation rate and hard radiation fluxes and corresponding radiation doses of dust in star-burst galaxies (1D and 2D distribution).
2.2 Connection between galactic nuclei activity and hard radiation fluxes and corresponding radiation doses of dust in such galaxies (1D and 2D distribution).
2.3 Ices and corresponding gas-phase molecules (also PAH, HAC, C60 etc.) as observational tools to differentiate between starburst and AGN type of activity.
2.4 Complex indicators of Cosmic ray dominating regions in special kind of active galaxies – HII galaxies, super-associations, blue compact dwarfs, WR galaxies, etc.
3. Disturbances of the Earth and (exo)planets atmospheres by external agents
3.1 Passing of the Sun through interstellar clouds: VUV and EP fluxes around planets with and without magnetic fields.
3.2 Solar superflares: VUV and EP fluxes around planets with and without magnetic fields.
3.3 Evolution of the heliosphere revealed by observations of solar-like star astrospheres: VUV and EP fluxes around planets with and without magnetic fields.

Methods and Tools of Investigation

Following methods and tools will be used for theoretical modeling and observational and experimental data accessing.


• CLOUDY (Ferland, 2013 - nublado.org) – the model and the corresponding computer code to calculate 1D physical and chemical conditions of static and dynamic interstellar clouds in the parameters set from intergalactic medium up to stellar disks (Yeghikyan, 2009; 2016a; 2016b; 2017a; 2017b). The latest versions take into account important non-thermal desorption of ices.


• SRIM code (Stopping and Range of Ions in Matter) (Ziegler, Biersack, 2013 - srim.org) – to calculate energy losses of EP in gas- and solid-phase species (Yeghikyan, 2008; 2011a; 2013c).


• CRST (Cosmic Ray Spectrum Transformation) – our own code to calculate the EP spectral transformation due to energy losses in dense media (Yeghikyan, 2011; Yeghikyan, Barsamyan, 2013c).


• ASTROCHEMISTRY-UCL. The time-dependent 1D model and code of the chemical evolution of the molecular cloud (kindly provided by Professors D. Williams and S. Viti, e.g. Yeghikyan, Viti, Williams, 2001). This code should be combined with CRST to study an important problem of a CR induced ionization rate distribution inside of the densest parts of molecular clouds and protoplanetary disks and, when applicable, to take into account ices evaporation processes.


• A2 (Aliphatization versus Aromatization) – our own model to calculate EP induced polycondensation of different type of hydrocarbons in the solid phase (Keheyan, Cataldo, Yeghikyan, 2004c).


• HELIOSPHERE-MC-EARTH. Our own the time-dependent 2D gasdynamical model and code of the heliosphere interacting with dense media in the case of the Sun passing through molecular clouds (Yeghikyan, Fahr, 2003, 2004a, 2006) using gasdynamical core of CLAWPACK (R. LeVeque, 1998; 2007)


• ATMOX (Atmospheric Oxygen) – our own model and code to calculate disturbed oxygen and ozone 1D distribution under influence of different external agents (Yeghikyan, Fahr, 2004a, 2004b, 2006). A new version takes into account external hydrogen, dust, VUV and EP fluxes disturbing the atmosphere.


• Open archival data (IRAS, ISO, Spitzer, Hershel, Alma, Fermi, etc).


• Sources of (VUV and EP) ionization radiation and IR spectroscopy (the program will be presented separately with the Department of the Nuclear Physics of the Yerevan State University, Institute of Physics, Institute of Physical Chemistry and The Molecules Structure Investigation Group of The Armenian Academy of Sciences).

Ararat YEGHIKYAN D.Sci., Leading Research Associate, Head of the Department
Anahit SAMSONYAN Junior Research Associate	Armen HAKOBYAN Junior Research Associate	Sama SHAMYAR Assistant Astronomer	Vladimir AIRAPETIAN (NASA/Goddard Space Flight Center, USA) PhD Foreign Research Associate

Collaboration, grants

• RA MES State Committee of Science, Armenia, research project No 15T-1C081. “ Investigation of stellar superflares of solar-like stars, their contribution into the origin of complex organic molecules in molecular clouds and protoplanets.”, Ashot Hakobyan – head of the group, Ararat Yeghikyan and Anahit Samsonyan - researchers, 01.01․2016-01.01.2018.


• ANSEF grant, PI - Anahit Samsonyan, Title: «Comparison of Far infrared [CII] 157micron and [OIII] 88 micron emission lines in Starburssts and AGN».
  A title of the Anahit Samsonyan PhD thesis, supervised by Prof. D. Weedman, to be finished in 2018, is "[CII] 158 mkm emission line in dusty starburst galaxies".


• "Complex indicators of Cosmic ray dominating regions in special kind of active galaxies – HII galaxies, super-associations, blue compact dwarfs, WR galaxies, etc", - informal collaboration with Dr. Jaklin Martirosyan, Yerevan State University, Department of General Physics and Astrophysics.


• "O,B star winds: the impact on the parent molecular cloud chemistry" – a title of the magister thesis of Virab Gevorgyan, 1st grade magister student, supervised by Dr. A. Yeghikyan, to be finished in May, 2018.


• "Stellar winds in planetary nebulae: the impact on the nebulae chemistry" – informal collaboration with a former magister student Sasun Gishyan, supervised by Dr. A. Yeghikyan, a probable PhD may be finished in 2020.


• AvH Foundation grant, Germany. Dr. Ararat Yeghikyan: Renewed research stay in Germany for a period of 01.06.2017 - 31.08.2017․ Title: Transfer of energetic particles in planetary nebulae: acceleration in interacting winds shocks and energy losses beyond the shock-front in the context of nebular dust irradiation․ In collaboration with Prof. Dr. Hans Fahr, Argelander Institute, University of Bonn․

Scientific Publications

Popular Publications

• Եղիկյան, Ա. 2008, Տեսակների զանգվածային բնաջնջման աստղաֆիզիկական տեսակետ


• Եղիկյան, Ա. 2009, Նյութի նախակենսաբանական էվոլյուցիայի մասին․ որտե՞ղ են առաջացել բարդ օրգանական միացությունները


• Եղիկյան, Ա. 2010, Արդյո՞ք Մարսի մթնոլորտում դիտվող մեթանը կենսածին բնույթ ունի


• Yeghikyan, A. 2013, Astrobiology, bio-mass-extinctions, and all that


• Եղիկյան, Ա. 2014, Աստղագիտության կապն այլ գիտությունների, մշակույթի և հասարակության հետ


• Եղիկյան, Ա. 2015, Արդյո՞ք Տիեզերքը միշտ է եղել բարենպաստ կյանքի առաջացման համար


• Yeghikyan, A. 2018, Does Iron in Armenian really means a Sky Drop?


• Եղիկյան, Ա. 2019, Կյանքի առաջացման աստղաֆիզիկական տեսակետը