69 citations · 387 across the 23 of their papers we have counts for
25 papers
Galactic Archaeology with the Subaru `Ōnohi`ula Prime Focus Spectrograph Strategic Program
Masashi Chiba, Rosemary F. G. Wyse, Evan N. Kirby +48
The recently commissioned Subaru `Ōnohi`ula Prime Focus Spectrograph (PFS) will obtain spectra from nearly 2,400 fibers that cover 1.24 square degrees. The 360 night Subaru Strateg…
Dynamical Evolution of Four Old Galactic Open Clusters traced by their constituent stars with \textit{Gaia} DR3
Shanmugha Balan, Khushboo K Rao, Kaushar Vaidya +2
We investigate the evolutionary stages of four open clusters, Berkeley 39, Collinder 261, NGC 6819, and NGC 7789, of ages ranging from 1.6 -- 6 Gyr. These clusters have previously…
Understanding stellar populations in thin & thick discs of edge-on galaxies with MUSE -- I. The case of the reignited S0 galaxy ESO 544-27
Devang Somawanshi, Souradeep Bhattacharya, Manish Kataria +1
Edge-on galaxies act as the best laboratories to understand the origin of thin and thick discs in galaxies. Measurement of spatially resolved stellar population properties in such…
Determination of dynamical ages of open clusters through the A parameter -- II
Khushboo K. Rao, Kaushar Vaidya, Manan Agarwal +2
Blue straggler stars (BSS), one of the most massive members of star clusters, have been used for over a decade to investigate mass segregation and estimate the dynamical ages of gl…
On the /Fe bimodality of the M31 disks
Chiaki Kobayashi, Souradeep Bhattacharya, Magda Arnaboldi +1
An outstanding question is whether the /Fe bimodality exists in disk galaxies other than in the Milky Way. Here we present a bimodality using our state-of-the-art galactic chemi…
RomAndromeda: The Roman Survey of the Andromeda Halo
Arjun Dey, Joan Najita, Carrie Filion +50
As our nearest large neighbor, the Andromeda Galaxy provides a unique laboratory for investigating galaxy formation and the distribution and substructure properties of dark matter…
The Andromeda Galaxy's Last Major Merger: Constraints from the survey of Planetary Nebulae
Souradeep Bhattacharya, Magda Arnaboldi, Ortwin Gerhard +7
The Andromeda galaxy (M 31) has experienced a tumultuous merger history as evidenced by the many substructures present in its inner halo. We use planetary nebulae (PNe) as chemodyn…
Weighing Andromeda: Mass estimates of the M~31 galaxy
Souradeep Bhattacharya
Andromeda (M 31) is the nearest giant spiral galaxy to our Milky Way, and over the past few decades, has been dubbed the most massive member of the Local Group. I explore the evolu…
The survey of planetary nebulae in Andromeda (M31) VI. Kinematics of M31 inner-halo substructures and comparison with major-merger simulation predictions
Souradeep Bhattacharya, Magda Arnaboldi, Francois Hammer +4
M31 has experienced a recent tumultuous merger history as evidenced from the many substructures that are still present in its inner halo, particularly the G1-Clump, NE- and W- shel…
Discovery of double BSS sequences in the old Galactic open cluster Berkeley 17
Khushboo K Rao, Souradeep Bhattacharya, Kaushar Vaidya +1
Blue straggler stars (BSS) are peculiar objects which normally appear as a single broad sequence along the extension of the main sequence. Only four globular clusters (GCs) have be…
A EDR3 search for tidal tails in disintegrating open clusters
Souradeep Bhattacharya, Khushboo K. Rao, Manan Agarwal +2
We carry out a search for tidal tails in a sample of open clusters with known relatively elongated morphology. We identify the member stars of these clusters from the precise astro…
The survey of planetary nebulae in Andromeda (M 31) V. Chemical enrichment of the thin and thicker discs of Andromeda. Oxygen to argon abundance ratios for planetary nebulae and H II regions
Magda Arnaboldi, Souradeep Bhattacharya, Ortwin Gerhard +6
We use oxygen and argon abundances for planetary nebulae (PNe) with low internal extinction (progenitor ages of (>4.5 Gyr) and high extinction (progenitor ages <2.5 Gyr), as well a…
The survey of planetary nebulae in Andromeda (M31). IV. Radial oxygen and argon abundance gradients of the thin and thicker disc
Souradeep Bhattacharya, Magda Arnaboldi, Nelson Caldwell +6
We obtain a magnitude-limited sample of Andromeda (M 31) disc PNe with chemical abundance estimated through the direct detection of the [OIII] 4363 line. Thi…
Tidal tails in the disintegrating open cluster NGC 752
Souradeep Bhattacharya, Manan Agarwal, Khushboo K. Rao +1
We utilize the robust membership determination algorithm, ML-MOC, on the precise astrometric and deep photometric data from Gaia Early Data Release 3 within a region of radius 5$^{…
Determination of dynamical ages of open clusters through the A parameter -- I
Khushboo K. Rao, Kaushar Vaidya, Manan Agarwal +1
The sedimentation level of blue straggler stars (BSS) has been shown to be a great tool to investigate the dynamical states of globular clusters (GCs). The area enclosed between th…
The survey of planetary nebulae in Andromeda (M31) III. Constraints from deep planetary nebula luminosity functions on the origin of the inner halo substructures in M31
Souradeep Bhattacharya, Magda Arnaboldi, Ortwin Gerhard +4
The Andromeda (M31) galaxy displays several substructures in its inner halo whose origin as remnants of accreted satellites or perturbations of the pre-existing disc are encoded in…
ML-MOC: Machine Learning (kNN and GMM) based Membership Determination for Open Clusters
Manan Agarwal, Khushboo K. Rao, Kaushar Vaidya +1
The existing open cluster membership determination algorithms are either prior dependent on some known parameters of clusters or are not automatable to large samples of clusters. I…
Blue Straggler Populations of Seven Open Clusters with Gaia DR2
Kaushar Vaidya, Khushboo K. Rao, Manan Agarwal +1
Blue straggler stars (BSS) are well studied in globular clusters but their systematic study with secure membership determination is lacking in open clusters. We use Gaia DR2 data t…
The survey of Planetary Nebulae in Andromeda (M31) II. Age-velocity dispersion relation in the disc from Planetary Nebulae
Souradeep Bhattacharya, Magda Arnaboldi, Nelson Caldwell +7
The age-velocity dispersion relation is an important tool to understand the evolution of the disc of the Andromeda galaxy (M31) in comparison with the Milky Way. We use Planetary N…
The survey of Planetary Nebulae in Andromeda (M31): I. Imaging the disk and halo with MegaCam@CFHT
Souradeep Bhattacharya, Magda Arnaboldi, Johanna Hartke +4
The Andromeda (M31) galaxy subtends nearly 100 sq. deg. on the sky, with severe contamination from the Milky Way halo stars whose surface density displays a steep gradient across t…
The blue straggler population of the old open cluster Berkeley 17
Souradeep Bhattacharya, Kaushar Vaidya, W. P. Chen +1
Blue Straggler Stars (BSSs) are observed in Galactic globular clusters and old open clusters. The radial distribution of BSSs has been used to diagnose the dynamical evolution of g…
Star formation toward the H~II region IRAS 10427-6032
Kaushar Vaidya, Souradeep Bhattacharya, Vatsal Panwar +3
The formation and properties of star clusters formed at the edges of H II regions are poorly known. We study stellar content, physical conditions, and star formation processes arou…
Chandra studies of the globular cluster 47 Tucanae: A deeper X-ray source catalogue, five new X-ray counterparts to millisecond radio pulsars, and new constraints to r-mode instability window
Souradeep Bhattacharya, Craig O. Heinke, Andrey I. Chugunov +3
We combined Chandra ACIS observations of the globular cluster 47 Tucanae (hereafter, 47 Tuc) from 2000, 2002, and 2014-15 to create a deeper X-ray source list, and study some of th…
Disintegration of the Aged Open Cluster Berkeley 17
Souradeep Bhattacharya, Ishan Mishra, Kaushar Vaidya +1
We present the analysis of the morphological shape of Berkeley 17, the oldest known open cluster (~10 Gyr), using a probabilistic star counting of Pan-STARRS point sources, and con…