Home
→
Recent submissions

IIA Institutional Repository: Recent submissions

Now showing items 41-60 of 8136

Impact of two severe geomagnetic storms on the ionosphere over Indian longitude sector during March-April 2023

Rajana, Siva Sai Kumar; Panda, Sampad Kumar; Jade, Sridevi; Vivek, Chiranjeevi G; Upadhayaya, A.K; Bhardwaj, Arti; Jorphail, S; Seemala, Gopi Krishna (Springer, 2024-01)

We investigated the ionosphere response to the two severe geomagnetic storms in the ascending phase of solar cycle 25 which occurred during the 23-24 March 2023 (SYM-Hmin = −169 nT) and 23-24 April 2023 (SYM-Hmin = −233 ...
Origin of the broadband emission from the transition blazar B2 1308+326

Pandey, Ashwani; Kushwaha, Pankaj; Wiita, Paul J; Prince, Raj; Czerny, Bożena; Stalin, C. S (EDP Sciences, 2024-01)

Context. Transition blazars exhibit a shift from one subclass to the next during different flux states. It is therefore crucial to study them to understand the underlying physics of blazars. Aims. We probe the origin of ...
Unravelling the post-collision properties of the Cartwheel galaxy: A MUSE exploration of its bar and inner region

Mondal, Chayan; Barway, Sudhanshu (EDP Sciences, 2024-01)

Aims. We aim to investigate the characteristics of the bar and inner disc in the collisional ring galaxy Cartwheel. Methods. We used integral field unit (IFU) observations from the Multi-Unit Spectroscopic Explorer (MUSE) ...
Shooting for the stars

India Today (2024-01-01)
UOCS – XI. Study of blue straggler stars in open cluster NGC 7142 using UVIT/AstroSat

Panthi, Anju; Vaidya, Kaushar; Vernekar, Nagaraj; Subramaniam, A; Jadhav, Vikrant; Agarwal, Manan (Oxford University Press on behalf of Royal Astronomical Society, 2024-01)

We present a study of blue straggler stars (BSSs) of open cluster NGC 7142 using AstroSat/UVIT data and other archival data. Using a machine-learning-based algorithm, ML-MOC, on Gaia DR3 data, we find 546 sources as cluster ...
Narrow-line Seyfert 1 galaxies in Sloan Digital Sky Survey: a new optical spectroscopic catalogue

Paliya, Vaidehi S; Stalin, C. S; Dominguez, Alberto; Saikia, D. J (Oxford University Press on behalf of Royal Astronomical Society, 2024-01)

Narrow-line Seyfert 1 (NLSy1) galaxies are an enigmatic class of active galactic nuclei (AGN) that exhibit peculiar multiwavelength properties across the electromagnetic spectrum. For example, these sources have allowed ...
Intensity and velocity oscillations in a flaring active region

Millar, David C. L; Fletcher, Lyndsay; Joshi, Jayant (Oxford University Press on behalf of Royal Astronomical Society, 2024-01)

Chromospheric oscillations can give us insight into the physical environment in the solar atmosphere, both in quiet Sun and flaring conditions. Many authors have reported increases in the prevalence of 3-minute oscillations ...
Role of magnetic pressure forces in fluctuation dynamo saturation

Sur, Sharanya; Subramanian, Kandaswamy (Oxford University Press on behalf of Royal Astronomical Society, 2024-01)

Using magnetohydrodynamic simulations of fluctuation dynamos in turbulent flows with rms Mach numbers Mrms = 0.2, 1.1, and 3, we show that magnetic pressure forces play a crucial role in dynamo saturation in supersonic ...
Unravelling the nuclear dust morphology of NGC 1365: a two-phase polar–RAT model for the ultraviolet to infrared spectral energy distribution

Swain, Subhashree; Shalima, P; Latha, K. V. P (Oxford University Press on behalf of Royal Astronomical Society, 2024-01)

We present a 3D radiative transfer model for the spectral energy distribution (SED) of NGC 1365, which is a ‘changing look’ Seyfert 1.8 type active galactic nucleus (AGN). The SED from the ultraviolet (UV) to the infrared ...
How does the presence of bar affects the fueling of supermassive black holes? An IllustrisTNG100 perspective

Kataria, Sandeep Kumar; Vivek, M (Oxford University Press on behalf of Royal Astronomical Society, 2024-01)

We conducted a statistical study of black hole masses of barred and unbarred galaxies in the IllustrisTNG100 cosmological magnetohydrodynamical simulations. This work aims to understand the role of the bars in the growth ...
Star formation history of the post-collisional Cartwheel galaxy using AstroSat/UVIT FUV images

Mayya, Y. D; Barway, Sudhanshu; Gomez-Gonzalez, V. M. A; Zaragoza-Cardiel, J (Oxford University Press on behalf of Royal Astronomical Society, 2024-01)

We present the results obtained by analysing the new AstroSat Ultra-Violet Imaging Telescope (UVIT) far-ultraviolet (FUV) image of the collisional-ring galaxy Cartwheel. The FUV emission is principally associated with the ...
Chemodynamical study of two CEMP-no stars from the Hamburg/ESO Survey

Shejeelammal, J; Goswami, A (Oxford University Press on behalf of Royal Astronomical Society, 2024-01)

The Carbon-Enhanced Metal-Poor (CEMP) stars with no enhancement of neutron-capture elements, the so-called CEMP-no stars are believed to be the direct descendants of first-generation stars and provide a unique opportunity ...
Spectral properties of GX 339−4 in the intermediate state using AstroSat observation

Jana, Arghajit; Chatterjee, Debjit; Chang, Hsiang-Kuang; Naik, Sachindra; Monda, Santanu (Oxford University Press on behalf of Royal Astronomical Society, 2024-01)

We present the results obtained from the spectral studies of black hole X-ray binary GX 339−4 using AstroSat observations during its 2021 outburst. AstroSat observed the source in the intermediate state for ∼600 ks. The ...
Eruption of prominence initiated by loss of equilibrium: multipoint observations

Vemareddy, P; Syed Ibrahim, M (Oxford University Press on behalf of Royal Astronomical Society, 2024-01)

Using the SDO/AIA, SOHO/LASCO, STEREO/SECCHI, and ground-based H α, radio observations, we studied a prominence eruption (PE) from the western limb that occurred on 2013 December 4. PE is associated with a moderate coronal ...
SWASTi-CME: A Physics-based Model to Study Coronal Mass Ejection Evolution and Its Interaction with Solar Wind

Mayank, Prateek; Vaidya, Bhargav; Mishra, Wageesh; Chakrabarty, D (American Astronomical Society, 2024-01)

Coronal mass ejections (CMEs) are primary drivers of space weather, and studying their evolution in the inner heliosphere is vital to prepare for a timely response. Solar wind streams, acting as background, influence their ...
Effect of low-mass galaxy interactions on their star formation

Subramanian, S; Mondal, Chayan; Kalari, Venu (EDP Sciences, 2024-01)

According to the Λ cold dark matter model of galaxy formation, the hierarchical assembly process is scale-free and interactions between galaxies in all mass ranges are expected. The effects of interactions between dwarf ...
Polarized resonance line transfer in a spherically symmetric medium with angle-dependent partial frequency redistribution

Sampoorna, M; Supriya, H. D (Oxford University Press on behalf of Royal Astronomical Society, 2023-12)

In a stellar atmosphere, the resonance line polarization arises from scattering of limb-darkened radiation field by atoms. This spectral line polarization gets affected particularly in the wings, when the line photons ...
Evolution of low-frequency quasi-periodic oscillations in GX 339-4 during its 2021 outburst using AstroSat data

Mondal, Santanu; Salgundi, Anirudh; Chatterjee, Debjit; Jana, Arghajit; Chang, H. K; Naik, Sachindra (Oxford University Press on behalf of Royal Astronomical Society, 2023-12)

The black hole X-ray binary GX 339-4 showed an X-ray outburst during 2021. The AstroSat captured this outburst when the source entered into the intermediate flux state while the count rate was declining. The source showed ...
X-ray polarization observations of IC 4329A with IXPE: Constraining the geometry of the X-ray corona

Pal, Indrani; Stalin, C. S; Chatterjee, Rwitika; Agrawal, Vivek K (Indian Academy of Sciences, 2023-12)

X-ray polarimetry is a powerful tool to probe the geometry of the hot X-ray corona in active galactic nuclei (AGN). Here, we present our results on the characterisation of the X-ray polarization of the radio-quiet Seyfert-type ...
Identifying the population of T-Tauri stars in Taurus: UV–optical synergy

Nayak, Prasanta K; Narang, Mayank; Puravankara, Manoj; Tyagi, Himanshu; Banerjee, Bihan; Sharma, Saurabh; Pandey, Rakesh; Surya, Arun; Mathew, Blesson; Arun, R; Ujjwal, K; Kartha, Sreeja S (Indian Academy of Sciences, 2023-12)

With the third data release of the Gaia mission, GaiaDR3with its precise photometry and astrometry, it is now possible to study the behavior of stars at a scale never seen before. In this paper, we developed new criteria ...

Recently added

IIA Institutional Repository: Recent submissions

Search DSpace

Browse

All of DSpace

My Account