A5070356403- Astrophysics and Star Formation Studies
- Molecular Spectroscopy and Structure
- Atmospheric Ozone and Climate
- Spectroscopy and Laser Applications
- Astro and Planetary Science
- Stellar, planetary, and galactic studies
- Advanced Chemical Physics Studies
- Astrophysics and Cosmic Phenomena
- Particle accelerators and beam dynamics
- Gyrotron and Vacuum Electronics Research
- Atomic and Molecular Physics
- Astronomical Observations and Instrumentation
- Synthesis and Biological Evaluation
- Fluorine in Organic Chemistry
- Scientific Research and Discoveries
- Advanced Combustion Engine Technologies
- Advanced Thermodynamic Systems and Engines
- Quantum, superfluid, helium dynamics
- Chemical Reactions and Mechanisms
- Calibration and Measurement Techniques
- Water Quality Monitoring and Analysis
- Solar and Space Plasma Dynamics
- Galaxies: Formation, Evolution, Phenomena
- Spectroscopy and Chemometric Analyses
- Advanced Physical and Chemical Molecular Interactions
Astro Space Center
2012-2023
Russian Academy of Sciences
2009-2023
P.N. Lebedev Physical Institute of the Russian Academy of Sciences
1994-2023
Polycyclic aromatic hydrocarbons and polycyclic nitrogen heterocycles are thought to be widespread throughout the Universe, because these classes of molecules probably responsible for unidentified infrared bands, a set emission features seen in numerous Galactic extragalactic sources. Despite their expected ubiquity, astronomical identification specific has proven elusive. We present discovery benzonitrile ($c$-C$_6$H$_5$CN), one simplest nitrogen-bearing molecules, interstellar medium....
Identifying PAHs in space Midinfrared spectroscopy has shown that polycyclic aromatic hydrocarbons (PAHs) are abundant many astronomical objects, but this technique cannot determine which specific PAH molecules present. Radio astronomy could provide individual identifications if the molecule is sufficiently and a large dipole moment, expected to produce numbers of very weak lines. McGuire et al. performed stacking matched filter analysis search for radio observations TMC-1, located within...
Abstract We present an overview of the GBT Observations TMC-1: Hunting Aromatic Molecules Large Program on Green Bank Telescope. This and a related program were launched to explore depth breadth aromatic chemistry in interstellar medium at earliest stages star formation, following our earlier detection benzonitrile ( c -C 6 H 5 CN) TMC-1. In this work, details observations, use archival data, data reduction strategies are provided. Using these propargyl cyanide (HCCCH 2 is described, as well...
We report an astronomical detection of HC$_4$NC for the first time in interstellar medium with Green Bank Telescope toward TMC-1 molecular cloud a minimum significance $10.5 \sigma$. The total column density and excitation temperature are determined to be $3.29^{+8.60}_{-1.20}\times 10^{11}$ cm$^{-2}$ $6.7^{+0.3}_{-0.3}$ K, respectively, using MCMC analysis. In addition HC$_4$NC, HCCNC is distinctly detected whereas no clear HC$_6$NC made. propose that dissociative recombination protonated...
A survey of the Class I methanol masers in transition |$7_0-6_1 \ {\rm A}^+$| at 44.07 GHz has been carried out with Parkes radio telescope. About 250 positions were searched direction Galactic H II regions, |${\rm H}_2{\rm O}$| and 6.7-GHz masers. 55 new emission sources 44 detected, amongst which is second strongest sky, M8E, a flux density 520 Jy. Most newly found are associated O}$|, OH presumably located common regions star formation. strong anticorrelation between was discovered. The...
A survey of Class II methanol masers at 6.7 GHz was made in the Northern hemisphere with 32-m Medicina radio telescope. 42 objects were detected, 20 them are new detections GHz. Our results show that detection rate toward inner part Galaxy is higher than other directions. It confirmed most associated faint compact HII regions. The large velocity dispersion and offset from parent molecular clouds.
A southern hemisphere survey of methanol emission sources has been carried out using the Australia Telescope National Facility Mopra millimetre telescope. 85 sources, majority them masers, have detected in 80−71 A+ transition at 95 GHz. Together with a similar northern survey, this completes search for 95-GHz from Galactic plane. The previously found correlation between intensities 44 and GHz is confirmed here larger sample sources. results large velocity gradient statistical equilibrium...
We report the detection of carbon-chain radical HC$_5$O for first time in interstellar medium toward dark cloud TMC-1 using 100 m Green Bank Telescope. observe four hyperfine components this $J = 17/2 \rightarrow 15/2$ rotational transition that originates from $^2\Pi_{1/2}$ fine structure level its ground state, and calculate an abundance $n/n_{H_2}$ $1.7\times 10^{-10}$, assuming excitation temperature $T_{ex} 7$~K. No indication HC$_3$O, HC$_4$O, HC$_6$O, is found these or archival...
A survey of young bipolar outflows in regions low-to-intermediate-mass star formation has been carried out two class I methanol maser transitions: 7_0-6_1A+ at 44 GHz and 4_{-1}-3_0E 36 GHz. We detected narrow features towards NGC 1333I2A, 1333I4A, HH25MMS, L1157 GHz, 2023 Flux densities the lines are no higher than 11 Jy relevant source luminosities about 10^{22} erg s{-1}, which is much lower those strong masers high-mass regions. No emission was found 39 outflows. All located clouds with...
We report the first interstellar detection of DC$_7$N and six $^{13}$C-bearing isotopologues HC$_7$N toward dark cloud TMC-1 through observations with Green Bank Telescope, confirm recent HC$_5$$^{15}$N. For average $^{13}$C isotopomers, DC$_7$N, HC$_5$$^{15}$N, we derive column densities 1.9(2)$\times$10$^{11}$, 2.5(9)$\times$10$^{11}$, 1.5(4)$\times$10$^{11}$ cm$^{-2}$, respectively. The resulting isotopic ratios are consistent previous values derived from similar species in source,...
The H II region RCW120 is a well-known object, which often considered as target to verify theoretical models of gas and dust dynamics in the interstellar medium. However, exact geometry still matter debate. In this work, we analyse observational data on molecular emission show that 13CO(2-1) C18O(2-1) lines are fitted by 2D model representing ring-like face-on structure. changing C18O(3-2) line profile from double-peaked single-peaked dense Condensation 1 might be signature stalled expansion...
A southern hemisphere survey of methanol emission sources in two millimetre-wave transitions has been carried out using the ATNF Mopra millimetre telescope. 16 have detected 31−40 A+ transition at 107 GHz, including six new exhibiting class II maser features. Combining these results with similar northern survey, a total eleven 107-GHz masers detected. 00−1−1 E 108 GHz resulted detection sources; one them showing characteristics. This is first presumably II. The large velocity gradient...
The results of the lowest frequency spectral survey carried out toward a molecular cloud and sensitive observations at selected frequencies are presented. entire Arecibo C-band (4--6 GHz) was observed towards cyanopolyyne peak TMC-1 with an rms sensitivity about 17--18 mK (about 2--2.5 mJy). In addition, number ranges within X-band (8--10 were longer integration times sensitivities 7--8 2 mJy) or higher. scan itself, already--known H2CO HC5N lines detected. However, in more frequencies, C2S,...
We observed 14 methanol transitions near lambda=2 mm in Galactic star-forming regions. Broad, quasi-thermal J(0)-J(-1)E lines 157 GHz were detected toward 73 sources. Together with the 6(-1)-5(0)E and 5(-2)-6(-1)E at 133 7(1)-7(0)E line 165 GHz, they used to study excitation. In majority of objects, Class I transition is inverted, II 6(0)-6(-1)E are overcooled. This exactly as predicted by models low gain masers. The absence inversion means that emission all objects arises areas without a...
We present a survey of 56 massive star-forming regions in the 44 GHz methanol maser transition made with Karl G. Jansky Very Large Array (VLA); 24 fields showed emission. The data allow us to demonstrate associations, at arcsecond precision, Class I emission outflows, HII regions, and shocks traced by 4.5 micron find total 83 components linewidths ranging from 0.17 3.3 km s$^{-1}$ nearly flat distribution median value 1.1 s$^{-1}$. relative velocities masers respect systemic velocity host...