Astrochemistry, Astrobiology and Exoplanets
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
- 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).
Following methods and tools will be used for theoretical modeling and observational and experimental data accessing.
Senior Research Associate,
Head of the Group
Junior Research Associate
Junior Research Associate
- 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 2012-2017
- Yeghikyan, A., Hakobyan Ashot., 2017, Possible solar superflare impact on the terrestrial atmosphere, in preparation.
- Yeghikyan, A., Samsonyan A., 2017, Ices in starburst galaxies, in preparation.
- Yeghikyan, A., Martirosyan, J., 2017, PAH in WR galaxies, in preparation.
- Yeghikyan, A., Gishyan, S., 2017, Stellar winds in planetary nebulae: the impact on the nebulae chemistry, in preparation.
- Yeghikyan, A., Gevorgyan, V., 2017, O,B star winds: the impact on the parent molecular cloud chemistry, in preparation.
- Yeghikyan, A. 2017, Astrochemistry as the basics for the astrobiology, in preparation.
- Yeghikyan, A., Fahr, H. 2017, On the effectivity of particle acceleration under conditions of interacting stellar winds in planetary nebulae, submitted.
- Yeghikyan, A. 2017, On the particles acceleration possibilities in WR nebulae shocks, submitted
- Hakobyan, Armen. 2017, Investigation of performance of the BAO 2.6 m telescope: influence of the main mirror's optical quality, submitted
- Yeghikyan, A., 2017, On dust irradiation in planetary nebulae in the context of survivability of ices, Molecular Astrophysics, 8, 40 - 47.
- Yeghikyan, A., 2017, Ices under conditions of planetary nebulae, in: Non-Stable Universe: Energetic Resources, Activity Phenomena and Evolutionary Processes, ASP Conf. Series, (Eds. A. M. Mickaelian, H. A. Harutyunian, E. H. Nikoghosyan), 511, 98-107.
- Yeghikyan, A., 2017, Evolution of energetic particle fluxes in the early heliosphere, Astrophysics, 60 (3), 374 – 386.
- Yeghikyan, A. 2017, The origin of life from the astrophysical point of view, 1st Int. Youth School-Conf. Proceedings, 4 pages, in press.
- Yeghikyan, A., 2016, Irradiation of ices inside molecular clouds in cosmic ray dominated regions of galaxies, in: Eds.: A. M. Mickaelian, H. G. Khosroshahi, H. A. Harutyunian.Proc.of Armenian-Iranian Astronomical Workshop, Yerevan, p. 162-169.
- Yeghikyan, A., 2016, On Survivability of Ices in Active Galaxies, in: Edited by A. Mickaelian, A. Lawrence and T. Magakian.ASP Conf. Series, Vol. 505, p.144-151.
- Samsonyan, A., L.; Using The Cornell Atlas of Spitzer/IRS Sources, Proceedings of an International Symposium dedicated to the 50th anniversary of the Markarian Survey and the 10th anniversary of the Armenian Virtual Observatory, Vol. 505, p.233, 2016
- Samsonyan, A., L.; Mid-Infrared [NeII] and [NeIII] Emission Line Profiles in Starbursts and AGN, Proceedings of Armenian-Iranian Astronomical Workshop (AIAW), "Gitutyun" Publishing House of the National Academy of Sciences of the Republic of Armenia (NAS RA), p. 200-204, 2016
- Samsonyan, Anahit; Weedman, Daniel; Lebouteiller, Vianney; Barry, Donald; Sargsyan, Lusine; Neon and [C II] 158 μm Emission Line Profiles in Dusty Starbursts and Active Galactic Nuclei, The Astrophysical Journal Supplement Series, Volume 226, Issue 1, article id. 11, 18 pp. (2016)
- Yeghikyan, A., 2015, Was the Universe always a convenient place for the origin of life? In: Eds.: H. A. Harutyunian, A. M. Mickaelian, S. V. Farmanyan. Yerevan, "Gitutyun", p. 72-82, (in Armenian, with English ''Abstract'').
- Sargsyan, L.; Samsonyan, A.; Lebouteiller, V.; Weedman, D.; Barry, D.; Bernard-Salas, J.; Houck, J.; Spoon, H.; Star Formation Rates from [C II] 158 mum and Mid-infrared Emission Lines for Starbursts and Active Galactic Nuclei; The Astrophysical Journal, Volume 790, Issue 1, article id. 15, 12 pp. (2014)
- Yeghikyan, A., Barsamyan, L., 2013, Irradiation of dust in molecular clouds. IV. ACR doses. Astrophysics, 56, 443-452.
- Yeghikyan, A., 2013, On the radii of astrospheres, Astrophysics, 56, 246-254.
- Yeghikyan, A., 2013, On dust irradiation in molecular clouds. III. Internal sources of stellar UV photons, Astrophysics, 56, 142-151.
- Yeghikyan, A. 2013, Astrobiology, biomass-extinctions and all that, ArAS News,64, 8-11.
- Melikian, N. D.; Tamazian, V. S.; Karapetian, A. A.; Samsonyan, A. L., Emission objects in Cyg OB7. Flare activity variation of UV Ceti, AIP Conference Proceedings, Volume 1452, pp. 73-79 (2012)
- Sargsyan L., Lebouteiller V., Weedman, D., Spoon H., Bernard-Salas J, Engels D., Stacey G., Houck J., Barry D., Miles J., Samsonyan A.;[C II] 158 μm Luminosities and Star Formation Rate in Dusty Starbursts and Active Galactic Nuclei; The Astrophysical Journal, Volume 755, Issue 2, article id. 171, 13 pp. (2012)
- Sargsyan, L.; Gevorgyan, M.; Abrahamyan, H.; Kostandyan, G.; Paronyan G.; Samsonyan, A.; Sargsyan, D.; Sinamyan, P.; Dust obscuration of the narrow line region of active galactic nuclei, Astrophysics, Volume 55, Issue 4, pp.460-470, 2012
- Yeghikyan, A. Does “iron” in Armenian really means a “sky drop” ? Inter. Conf. “Astronomical Heritage of the Middle East”, Byurakan, November 13-17 2017.
- Yeghikyan, A. 2017, On the particles acceleration possibilities in WR nebulae shocks, Stellar Associations: 70 Years of Research, Byurakan, Sept. 2017.
- Yeghikyan, A. 2017, The origin of life from the astrophysical point of view, 1st Int. Youth School-Conf. Proceedings, Byurakan, Sept. 2017.
- Anahit Samsonyan, Dual AGNs observed with NOT and INT, Stellar Associations: 70 Years of Research, Byurakan, Sept. 2017.
- A. Samsonyan, Velocity Dispersions in Mid Infrared Neon and Far Infrared [CII] Emission Lines for Starbursts and AGN, EWASS2017, poster: 26-30 June 2017, Prague, Czeck Republic.
Proceedings of Meetings