National Research Lobachevsky State University of Nizhny Novgorod
Russian Federation
UDK 53 Физика
UDK 520 Инструменты, приборы и методы астрономических наблюдений, измерений и анализа
UDK 521 Теоретическая астрономия. Небесная механика. Фундаментальная астрономия. Теория динамической и позиционной астрономии
UDK 523 Солнечная система
UDK 524 Звезды и звездные системы. Вселенная Солнце и Солнечная система
UDK 52-1 Метод изучения
UDK 52-6 Излучение и связанные с ним процессы
GRNTI 41.00 АСТРОНОМИЯ
GRNTI 29.35 Радиофизика. Физические основы электроники
GRNTI 29.31 Оптика
GRNTI 29.33 Лазерная физика
GRNTI 29.27 Физика плазмы
GRNTI 29.05 Физика элементарных частиц. Теория полей. Физика высоких энергий
OKSO 03.06.01 Физика и астрономия
OKSO 03.05.01 Астрономия
OKSO 03.04.03 Радиофизика
BBK 2 ЕСТЕСТВЕННЫЕ НАУКИ
BBK 223 Физика
TBK 614 Астрономия
TBK 6135 Оптика
BISAC SCI004000 Astronomy
BISAC SCI005000 Physics / Astrophysics
Massive stars play an important role in the Universe. Unlike low-mass stars, the formation of these objects located at great distances is still unclear. It is expected to be governed by some combination of self-gravity, turbulence, and magnetic fields. Our aim is to study the chemical and physical conditions of dense clumps in several high-mass star-forming regions. We performed observations towards 5 high-mass star-forming regions (L1287, S187, S231, DR 21(OH), NGC 7538) with the IRAM 30-m telescope. We covered the 2-3 and 4 mm wavelength bands and analysed the lines of HCN, HNC, HCO$^+$, HC$_3$N, HNCO, OCS, CS, SiO, SO$_2$, and SO. Using the astrodendro algorithm on the 850 $\mu$m dust emission data from the SCUBA Legacy catalogue, we identified dense gas clumps and assessed their masses, H$_2$ column densities, and sizes. Furthermore, the kinetic temperatures, molecular abundances and dynamical state were obtained. The Red Midcourse Space Experiment Source survey (RMS) was utilized to identify the types of clumps. A total of 20 clumps were identified. We found no significant correlation between line width and size, but the linewidth-mass and mass-size relationships are strongly correlated. Virial analysis indicated that the clumps with H II regions and young stellar objects (YSOs) are gravitationally bound. Furthermore, it was suggested that significant magnetic fields provide additional support for clump stability. Molecular abundances show a decreasing trend from YSOs to submm and H II regions.
ISM: abundances, molecules; stars: formation, massive; astrochemistry
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