Search Publications
Membership determination in open clusters using the DBSCAN Clustering Algorithm
Hasan, P.; Raja, M.; Mahmudunnobe, Md. +2 more
In this paper, we apply the machine learning clustering algorithm Density Based Spatial Clustering of Applications with Noise (DBSCAN) to study the membership of stars in twelve open clusters (NGC 2264, NGC 2682, NGC 2244, NGC 3293, NGC 6913, NGC 7142, IC 1805, NGC 6231, NGC 2243, NGC 6451, NGC 6005 and NGC 6583) based on Gaia DR3 Data. This sampl…
Using GMM in open cluster membership: An insight
Hasan, P.; Raja, M.; Hasan, S. N. +2 more
The unprecedented precision of Gaia has led to a paradigm shift in membership determination of open clusters where a variety of machine learning (ML) models can be employed. In this paper, we apply the unsupervised Gaussian Mixture Model (GMM) to a sample of thirteen clusters with varying ages (log t ≈ 6.38-9.64) and distances (441-5183 pc) from G…
LCGCT: A light curve generator in customisable-time-bin based on time-series database
Xu, Y.; Cui, C.; Fan, D. +1 more
In the era of time-domain astronomy, scientists often need to generate light curves with varying time-bin. However, an increase in time resolution typically leads to a substantial increase in data transmission. To enhance the data processing efficiency in time-domain astronomy, we propose a novel time-series data model for storing time-series obse…
Reconstructing the mid-infrared spectra of galaxies using ultraviolet to submillimeter photometry and Deep Generative Networks
Efstathiou, A.; Rissaki, Agapi; Pavlou, O. +2 more
The mid-infrared spectra of galaxies are rich in features such as the Polycyclic Aromatic Hydrocarbon (PAH) and silicate dust features which give valuable information about the physics of galaxies and their evolution. For example they can provide information about the relative contribution of star formation and accretion from a supermassive black …
Classifying the clouds of Venus using unsupervised machine learning
Molaverdikhani, K.; Grassi, T.; Ercolano, B. +2 more
Because Venus is completely shrouded by clouds, they play an important role in the planet's atmospheric dynamics. Studying the various morphological features observed on satellite imagery of the Venusian clouds is crucial to understanding not only the dynamic atmospheric processes, but also interactions between the planet's surface structures and …
Planetary orbital mapping and mosaicking (POMM) integrated open source software environment
Logan, Thomas L.; Smyth, Michael M.; Calef, Fred J.
Several Open Source planetary orbital mapping and utility image processing software packages, including, VICAR, AFIDS, ISIS, GDAL, and GeoTIFF, have been integrated into a single software environment (POMM), where package programs can be run independently from a Linux command line, or combined in synergistic scripts that facilitate advanced trans-…
The effect of baseline on the uncertainties of range determination performed by two-site astrometric observations. A sample case for the triangulation method: TURKSAT 3A and TURKSAT 4A
Gökay, H. G.; Özdemi̇r, S.; Bağıran, M. N. +1 more
The uncertainties in range determination depending on two-site locations for GEO satellites were calculated and shown that the uncertainty in the range depends not only on linear baseline distance between the locations but also both latitude and longitude of geographic coordinates of the sites. By taking the first observing site as fixed and chang…