activity
20092025
most citedSEGUE: A Spectroscopic Survey of 240,000 stars with g=14-20

1.2k citations · 1.3k across the 22 of their papers we have counts for

collaborators

23 papers

astro-ph.EP2025

High-Resolution Echelle Spectroscopy for Solar System Planets: A Planet-as-Point-Source Analogy

Parvathy Menon, Sivarani T, Sriram S +4

Transmission spectroscopy has proven to be an effective technique for characterizing exoplanet atmospheres. However, transmission spectroscopy requires planetary transits, which oc…

astro-ph.EP2025

Addressing wavelength-correlated systematics in exoplanet transmission spectroscopy: a 2D Gaussian Process approach

Lokesh Manickavasaham, Manjunath Bestha, Sivarani Thirupathi +2

Ground-based transmission spectroscopy is often dominated by systematics, which obstructs our ability to leverage the advantages of larger aperture sizes compared to space-based ob…

astro-ph.IM2025

Atmospheric Dispersion Measurement at Hanle Site

Manjunath Bestha, Sivarani Thirupathi, Athira Unni +2

Atmospheric dispersion introduces wavelength-dependent effects that significantly impact ground-based observations, particularly in slit- and fibre-fed spectroscopic studies. These…

astro-ph.EP2025

An Initial Assessment of the Hanle Echelle Spectrograph for Exoplanet Atmosphere Studies

Manjunath Bestha, Athira Unni, T. Sivarani +6

Transmission spectroscopy is an effective technique for probing exoplanetary atmospheres. While most observations have relied on space facilities such as HST and JWST, ground-based…

astro-ph.IM2023★ 1 cited

Recovering simulated planet and disk signals using SCALES aperture masking

Mackenzie Lach, Steph Sallum, Ravinder Banyal +29

The Slicer Combined with Array of Lenslets for Exoplanet Spectroscopy (SCALES) instrument is a lenslet-based integral field spectrograph that will operate at 2 to 5 microns, imagin…

astro-ph.IM2023

Simulating medium-spectral-resolution exoplanet characterization with SCALES angular/reference differential imaging

Aditi Desai, Stephanie E. Sallum, Ravinder Banyal +30

SCALES (Slicer Combined with Array of Lenslets for Exoplanet Spectroscopy) is a 2 - 5 micron high-contrast lenslet-based integral field spectrograph (IFS) designed to characterize…

astro-ph.IM2023

The Slicer Combined with Array of Lenslets for Exoplanet Spectroscopy (SCALES): driving science cases and expected outcomes

Steph Sallum, Andrew Skemer, Deno Stelter +34

The Slicer Combined with Array of Lenslets for Exoplanet Spectroscopy (SCALES) is a m, high-contrast integral field spectrograph (IFS) currently being built for Keck Observa…

astro-ph.SR2023★ 8 cited

Field blue straggler stars: Discovery of white dwarf companions to blue metal-poor stars using UVIT/AstroSat

Anju Panthi, Annapurni Subramaniam, Kaushar Vaidya +4

Blue metal-poor (BMP) stars are the main-sequence stars that appear bluer and more luminous than normal turn-off stars of metal-poor globular clusters. They are believed to be eith…

astro-ph.SR2022★ 6 cited

Globular Cluster UVIT legacy Survey (GlobUleS) III. Omega Centauri in Far-Ultraviolet

Deepthi S. Prabhu, Annapurni Subramaniam, Snehalata Sahu +21

We present the first comprehensive study of the most massive globular cluster Omega Centauri in the far-ultraviolet (FUV) extending from the center to ~ 28% of the tidal radius usi…

astro-ph.IM2022

Design of SCALES: A 2-5 Micron Coronagraphic Integral Field Spectrograph for Keck Observatory

Andrew Skemer, R. Deno Stelter, Stephanie Sallum +49

We present the design of SCALES (Slicer Combined with Array of Lenslets for Exoplanet Spectroscopy) a new 2-5 micron coronagraphic integral field spectrograph under construction fo…

astro-ph.GA2022★ 14 cited

Globular Clusters UVIT Legacy Survey (GlobULeS) I. FUV-optical Color-Magnitude Diagrams for Eight Globular Clusters

Snehalata Sahu, Annapurni Subramaniam, Gaurav Singh +22

We present the first results of eight Globular Clusters (GCs) from the AstroSat/UVIT Legacy Survey program GlobULeS based on the observations carried out in two FUV filters (F148W…

astro-ph.SR2020★ 9 cited

A high-resolution spectroscopic study of two new Na- and Al-rich field giants -- likely globular cluster escapees in the Galactic halo

Avrajit Bandyopadhyay, Sivarani Thirupathi, Timothy C. Beers +1

The stars SDSS J064655.6+411620.5 and SDSS J193712.01+502455.5 are relatively bright stars that were initially observed as part of the SDSS/MARVELS pre-survey. They were selected,…

astro-ph.IM2019★ 37 cited

The Detailed Science Case for the Maunakea Spectroscopic Explorer, 2019 edition

The MSE Science Team, Carine Babusiaux, Maria Bergemann +258

(Abridged) The Maunakea Spectroscopic Explorer (MSE) is an end-to-end science platform for the design, execution and scientific exploitation of spectroscopic surveys. It will unvei…

astro-ph.IM2018★ 7 cited

The Maunakea Spectroscopic Explorer Book 2018

Alexis Hill, Nicolas Flagey, Alan McConnachie +122

(Abridged) This is the Maunakea Spectroscopic Explorer 2018 book. It is intended as a concise reference guide to all aspects of the scientific and technical design of MSE, for the…

astro-ph.SR2018★ 15 cited

Chemical composition of two bright extremely metal-poor stars from the SDSS MARVELS pre-survey

Avrajit Bandyopadhyay, Sivarani Thirupathi, Antony Susmitha +4

\sdsszeroeight\ (V = 11.4; [Fe/H] = 3.1) and \sdssonethree\ (V = 12.4; [Fe/H] = 3.2) were observed with the SDSS 2.5-m telescope as part of the SDSS-MARVELS spectroscopic pre…

astro-ph.IM2017★ 3 cited

Performance results of HESP physical model

Anantha Chanumolu, Sivarani Thirupathi, Damien Jones +3

As a continuation to the published work on model based calibration technique with HESP(Hanle Echelle Spectrograph) as a case study, in this paper we present the performance results…

astro-ph.EP2016★ 17 cited

Very Low-Mass Stellar and Substellar Companions to Solar-like Stars From MARVELS VI: A Giant Planet and a Brown Dwarf Candidate in a Close Binary System HD 87646

Bo Ma, Jian Ge, Alex Wolszczan +34

We report the detections of a giant planet (MARVELS-7b) and a brown dwarf candidate (MARVELS-7c) around the primary star in the close binary system, HD 87646. It is the first close…

astro-ph.IM2016★ 31 cited

The Detailed Science Case for the Maunakea Spectroscopic Explorer: the Composition and Dynamics of the Faint Universe

Alan McConnachie, Carine Babusiaux, Michael Balogh +173

MSE is an 11.25m aperture observatory with a 1.5 square degree field of view that will be fully dedicated to multi-object spectroscopy. More than 3200 fibres will feed spectrograph…

astro-ph.IM2015★ 9 cited

Modelling high resolution Echelle spectrographs for calibrations: Hanle Echelle spectrograph, a case study

Anantha Chanumolu, Damien Jones, Sivarani Thirupathi

We present a modelling scheme that predicts the centroids of spectral line features for a high resolution Echelle spectrograph to a high accuracy. Towards this, a computing scheme…

astro-ph.IM2015

Thirty Meter Telescope International Observatory Detailed Science Case 2024

Warren Skidmore, Bob Kirshner, David Andersen +168

The Thirty Meter Telescope (TMT) International Observatory (TIO) will be a revolutionary leap forward in astronomical observing capabilities, enabling us to address some of the mos…

astro-ph.GA2015

Investigating the AGN activity and black hole masses in Low Surface brightness galaxies

Smitha Subramanian., Ramya. S., Mousumi Das. +3

We present an analysis of the optical nuclear spectra from the active galactic nuclei (AGN) in a sample of giant low surface brightness (GLSB) galaxies. GLSB galaxies are extreme l…

astro-ph.SR2009★ 5 cited

Automated Determination of [Fe/H] and [C/Fe] from Low-Resolution Spectroscopy

B. Marsteller, T. C. Beers, T. Sivarani +5

We develop an automated spectral synthesis technique for the estimation of metallicities ([Fe/H]) and carbon abundances ([C/Fe]) for metal-poor stars, including carbon-enhanced met…

astro-ph.GA2009★ 1.2k cited

SEGUE: A Spectroscopic Survey of 240,000 stars with g=14-20

II SEGUE Collaboration, Brian Yanny, Constance Rockosi +2

The SEGUE survey obtained 240,000 moderate resolution (R = 1800) spectra from 3900 - 9000 Angstroms of fainter Milky Way stars (14.0 < g < 20.3) of a wide variety of spectral types…