A5044202948- Astrophysics and Star Formation Studies
- Stellar, planetary, and galactic studies
- Astro and Planetary Science
- Atmospheric Ozone and Climate
- Molecular Spectroscopy and Structure
- Gamma-ray bursts and supernovae
- Pulsars and Gravitational Waves Research
- Geophysics and Gravity Measurements
- Solar and Space Plasma Dynamics
- Astrophysics and Cosmic Phenomena
- Radio Astronomy Observations and Technology
- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Advanced Chemical Physics Studies
- Advanced Combustion Engine Technologies
- Spacecraft and Cryogenic Technologies
- Space Exploration and Technology
- Spectroscopy and Laser Applications
- Ionosphere and magnetosphere dynamics
- Atmospheric and Environmental Gas Dynamics
Indian Institute of Space Science and Technology
2021-2024
ABSTRACT We investigate the presence of hub-filament systems in a large sample 146 active proto-clusters, using H13CO+ J = 1-0 molecular line data obtained from ATOMS survey. find that filaments are ubiquitous and very common dense core scales (∼0.1 pc) to clump/cloud (∼1–10 pc). The proportion proto-clusters containing decreases with increasing dust temperature (Td) luminosity-to-mass ratios (L/M) clumps, indicating stellar feedback H ii regions gradually destroys as evolve. Clear velocity...
ABSTRACT We present a statistical study of sample 17 hub-filament-system (HFS) clouds high-mass star formation using high-angular resolution (∼1–2 arcsec) ALMA 1.3 and 3 mm continuum data. The includes eight infrared (IR)-dark nine IR-bright types, which correspond to an evolutionary sequence from the IR-dark stage. central massive clumps their associated most cores are observed follow trend increasing mass (M) surface density (Σ) with evolution In addition, mass-segregated cluster young...
We present a comprehensive study of the gas kinematics associated with density structures at different spatial scales in filamentary infrared dark cloud, G034.43+00.24 (G34). This makes use H13CO+ (1-0) molecular line data from ALMA Three-millimeter Observations Massive Star-forming regions (ATOMS) survey, which has and velocity resolution 0.04 pc 0.2 km/s, respectively. Several tens dendrogram have been extracted position-position-velocity space H13CO+, include 21 small-scale leaves 20...
Abstract There is growing evidence that high-mass star formation and hub-filament systems (HFS) are intricately linked. The gas kinematics along the filaments forming star(s) in central hub excellent agreement with new generation of global hierarchical models. In this paper, we present an observational investigation a typical HFS cloud, G310.142+0.758 (G310 hereafter), which reveals unambiguous mass inflow from cloud scale via onto protostar(s) at conforming model predictions. Continuum...
ABSTRACT We present new 3-mm continuum and molecular lines observations from the ATOMS survey towards massive protostellar clump, MM1, located in filamentary infrared dark cloud (IRDC), G034.43+00.24 (G34). The observed are tracers of either dense gas (e.g. HCO+/H13CO+ J= 1–0) or outflows CS 2–1). most complete picture to date seven cores MM1 is revealed by dust emission. These found be gravitationally bound, with virial parameter, αvir < 2. At least four identified a total outflowing...
ABSTRACT We present new continuum and molecular line data from the ALMA Three-millimeter Observations of Massive Star-forming regions (ATOMS) survey for two protoclusters, G12.42+0.50 G19.88−0.53. The 3 mm maps reveal seven cores in each globally contracting protoclusters. These satisfy radius–mass relation surface mass density criteria high-mass star formation. Similar to their natal clumps, virial analysis suggests that they are undergoing gravitational collapse ($\rm \alpha _{vir} \lt...
PSR J2030+4415 is a gamma-ray pulsar with an X-ray wind nebula elongated along the north-south direction. The system shows prominent filament oriented at angle of 130{\deg} to axis. To improve our understanding non-thermal processes occurring in nebula, we attempted determine possible existence radio counterpart, study its morphology, and obtain restrictive upper limits emission wavelengths. We performed observations surroundings upgraded Giant Metrewave Radio Telescope (uGMRT) two frequency...
Context. In about 2000, the south pole of Triton experienced an extreme summer solstice that occurs every ∼650 years, when subsolar latitude reached 50°S. Bracketing this epoch, a few occultations probed atmosphere in 1989, 1995, 1997, 2008, and 2017. A recent ground-based stellar occultation observed on 6 October 2022 provides new measurement atmospheric pressure Triton. This is presented here. Aims. The goal to constrain volatile transport models (VTMs) atmosphere. basically vapor...
Abstract This paper presents an overview of the QUARKS survey, which stands for “Querying Underlying mechanisms massive star formation with ALMA-Resolved gas Kinematics and Structures.” The survey is observing 139 clumps covered by 156 pointings at Atacama Large Millimeter/submillimeter Array (ALMA) Band 6 ( λ ∼ 1.3 mm). In conjunction data obtained from ALMA-ATOMS 3 mm), aims to carry out unbiased statistical investigation process within protoclusters down a scale 1000 au. describes...
Abstract We present a detailed structural and gas kinematic study of the star-forming complex W5-NW. A cloud–cloud collision scenario unravels with evidence collision-induced star cluster formation. Various signatures such as “complementary distribution” “bridging features” are explored. At colliding region, two clouds have complementary morphologies, where W5-NWb has filamentary key-like shape that fits into U-shaped cavity in W5-NWa behaves like keyhole. The interaction region between is...
Abstract Using new continuum and molecular line data from the Atacama Large Millimeter/submillimeter Array Three-millimeter Observations of Massive Star-forming Regions (ATOMS) survey archival Very Array, 4.86 GHz data, we present direct observational evidence hierarchical triggering relating three epochs massive star formation in a ringlike H ii region, G24.47+0.49. We find radio flux analysis that it is excited by star(s) spectral type O8.5V–O8V first epoch formation. The swept-up ionized...
Context. Massive stars produce strong stellar winds that consist of continuous outflows material at speeds thousands km s −1 . These convey large amounts kinetic power, especially in the case Wolf–Rayet (WR) stars. When these interact with nearby material, they will likely shocks. Among other processes, particle acceleration is expected to occur. This particularly well established massive binary systems, where collide, allowing systems be identified thanks detection synchrotron radio...
ABSTRACT Large wind kinetic power of Wolf-Rayet (WR) stars make them ideal targets in low radio frequencies to search for non-thermal emission due relativistic particle acceleration. In this paper, we present observations two WR stars, 114 and 142, Band 4 (550–950 MHz) 5 (1050–1450 using the upgraded Giant Meterwave Radio Telescope. Neither star is detected observed frequency bands, nor extended associated with them. The upper limit free–free from stellar enables us constrain mass-loss rate...
In recent years, systems involving massive stars with large wind kinetic power have been considered as promising sites for investigating relativistic particle acceleration in low radio frequencies. With this aim, we observed two Wolf-Rayet systems, WR 114 and 142, using upgraded Giant Meterwave Radio Telescope observations Band 4 (550–950 MHz) 5 (1050–1450 MHz). None of the targets was detected at these Based on non-detection, report 3𝜎 upper limits to flux densities 735 1260 MHz (123 66 𝜇Jy...
Massive stars produce strong stellar winds that consist of continuous outflows material at speeds thousands km/s. These convey large amounts kinetic power, especially in the case Wolf-Rayet (WR) stars. When these interact with nearby material, they will likely shocks. Among other processes, particle acceleration is expected to occur. This particularly well established massive binary systems, where collide, allowing systems be identified thanks detection synchrotron radio emission, produced...
PSR,J2030$+$4415 is a gamma-ray pulsar with an X-ray wind nebula elongated along the north--south direction. The system shows prominent filament oriented at angle of 130° to axis. To improve our understanding non-thermal processes occurring in nebula, we attempted determine possible existence radio counterpart, study its morphology, and obtain restrictive upper limits emission wavelengths. We performed observations surroundings upgraded Giant Metrewave Radio Telescope (uGMRT) two frequency...
We present a detailed structural and gas kinematic study of the star-forming complex W5-NW. A cloud-cloud collision scenario unravels with evidences induced star cluster formation. Various signatures such as "complementary distribution" "bridging-features" are explored. At colliding region, two clouds have complementary morphologies, where W5-NWb has filamentary key-like shape which fits into U-shaped cavity in W5-NWa that behaves like keyhole. The interaction region between is characterised...
Using new continuum and molecular line data from the ALMA Three-millimeter Observations of Massive Star-forming Regions (ATOMS) survey archival VLA, 4.86 GHz data, we present direct observational evidence hierarchical triggering relating three epochs massive star formation in a ring-like H II region, G24.47+0.49. We find radio flux analysis that it is excited by star(s) spectral type O8.5V-O8V first epoch formation. The swept-up ionized ring structure shows secondary collapse, within this...
ABSTRACT Hub-filament systems are considered as natural sites for high-mass star formation. Kinematic analysis of the surroundings hub-filaments is essential to better understand formation within such systems. In this work, we present a detailed study massive Galactic protocluster IRAS 15394$-$5358, using continuum and molecular line data from ALMA three-millimetre observations star-forming regions (ATOMS) survey. The 3 mm dust map reveals fragmentation ($\rm M=843~{\rm M}_{\odot }$) clump...
Hub-filament systems are considered as natural sites for high-mass star formation. Kinematic analysis of the surroundings hub-filaments is essential to better understand formation within such systems. In this work, we present a detailed study massive Galactic protocluster IRAS 15394$-$5358, using continuum and molecular line data from ALMA Three-millimeter Observations Massive Star-forming Regions (ATOMS) survey. The 3~mm dust map reveals fragmentation ($\rm M=843~M_{\odot}$) clump into six...
The production of silicon monoxide (SiO) can be considered as a fingerprint shock interaction. In this work, we use high-sensitivity observations the SiO (2-1) and H$^{13}$CO$^{+}$ (1-0) emission to investigate broad narrow toward 146 massive star-forming regions in ATOMS survey. We detected 136 distinguished components across extension 118 sources (including 58 UC $H_{II}$ regions) with an average angular resolution 2.5$^{\prime}$$^{\prime}$. derived luminosity ($L_{SiO}$) whole sample...
Abstract The production of silicon monoxide (SiO) can be considered as a fingerprint shock interaction. In this work, we use high-sensitivity observations the SiO (2-1) and H13CO+ (1-0) emission to investigate broad narrow toward 146 massive star-forming regions in ATOMS survey. We detected 136 distinguished components across extension 118 sources (including 58 UC H ii regions) with an average angular resolution 2.5′ ′. derived luminosity ($L_\mbox{SiO}$) whole sample shows that majority...
We present a statistical study of sample 17 hub-filament-system (HFS) clouds high-mass star formation using high-angular resolution ($\sim$1-2 arcsecond) ALMA 1.3mm and 3mm continuum data. The includes 8 infrared (IR)-dark 9 IR-bright types, which correspond to an evolutionary sequence from the IR-dark stage. central massive clumps their associated most cores are observed follow trend increasing mass ($M$) surface density ($Σ$) with evolution In addition, mass-segregated cluster young...
There is growing evidence that high-mass star formation and hub-filament systems (HFS) are intricately linked. The gas kinematics along the filaments forming star(s) in central hub excellent agreement with new generation of global hierarchical models. In this paper, we present an observational investigation a typical HFS cloud, G310.142+0.758 (G310 hereafter) which reveals unambiguous mass inflow from cloud scale via onto protostar(s) at conforming model predictions. Continuum molecular line...
Large wind kinetic power of Wolf-Rayet (WR) stars make them ideal targets in low radio frequencies to search for non-thermal emission due relativistic particle acceleration. In this paper, we present observations two WR stars, 114 and 142, Band 4 (550-950 MHz) 5 (1050-1450 using the upgraded Giant Meterwave Radio Telescope (uGMRT). Neither star is detected observed frequency bands, nor extended associated with them. The upper limit free-free from stellar enables us constrain mass-loss rate...