100 citations · 347 across the 20 of their papers we have counts for
23 papers
Comparing the contrast performance of two IFU technologies for exoplanet direct imaging with ELT-PCS
Ryan Griffiths, Siddharth Maharana, Matthias Tecza
A key science goal for the Planetary Camera and Spectrograph (ELT-PCS) instrument is to image rocky exoplanets in reflected light around nearby M- and K-dwarfs. These observations…
Commissioning and on-sky performance of FiberPol: a fiber-fed spectropolarimetric system for the SAAO 1.9 m telescope
Siddharth Maharana, K. C. J. Dennison-Farrar, Sabyasachi Chattopadhyay +8
At the South African Astronomical Observatory (SAAO), we have developed FiberPol a spectropolarimetric front-end for the SpUpNIC spectrograph on the 1.9 m telescope fed by fiber…
WALOP-South: a four camera one shot imaging polarimeter for the PASIPHAE survey. Paper III -- PSF modelling
Indrajit Paul, Kishan Deka, Tuhin Ghosh +22
The two WALOP instruments, built for the PASIPHAE survey, will measure the linear polarization of large numbers of stars in the Galactic polar regions in the SDSS- band. They ar…
Evidence for cloud-to-cloud variations in the ratio of polarized thermal dust emission to starlight polarization
Nidhi Mehandiratta, Georgia V. Panopoulou, Eirik Gjerløw +12
The correlation between optical starlight polarization and polarized thermal dust emission can be used to infer intrinsic dust properties. This correlation is quantified by the rat…
Wide Area Linear Optical Polarimeter Control Software
John A. Kypriotakis, Bhushan Joshi, Dmitry Blinov +19
The WALOPControl software is designed to facilitate comprehensive control and operation of the WALOP (Wide Area Linear Optical Polarimeter) polarimeters, ensuring safe and concurre…
High optical to X-ray polarization ratio reveals Compton scattering in BL Lacertae's jet
Ivan Agudo, Ioannis Liodakis, Jorge Otero-Santos +147
Blazars, supermassive black hole systems (SMBHs) with highly relativistic jets aligned with the line of sight, are the most powerful long-lived emitters of electromagnetic emission…
The WALOP-North Instrument I: Optical Design, Filter Design, Calibration
John A. Kypriotakis, Siddharth Maharana, Ramya M. Anche +18
The Wide Area Linear Optical Polarimeter North (WALOP-North) is an optical polarimeter designed for the needs of the PASIPHAE survey. It will be installed on the 1.3m telescope at…
Improving polarimetric accuracy of RoboPol to 0.05 % using a half-wave plate calibrator system
Siddharth Maharana, Dmitry Blinov, A. N. Ramaprakash +2
RoboPol is a four-channel, one-shot linear optical polarimeter that has been successfully operating since 2013 on the 1.3 m telescope at Skinakas Observatory in Crete, Greece. Usin…
Systems design, assembly, integration and lab testing of WALOP-South Polarimeter
Siddharth Maharana, A. N. Ramaprakash, Chaitanya Rajarshi +28
Wide-Area Linear Optical Polarimeter (WALOP)-South is the first wide-field and survey-capacity polarimeter in the optical wavelengths. On schedule for commissioning in 2024, it wil…
FiberPol-6D: Spectropolarimetric Integral Field mode for the SAAO 1.9 m Telescope using fibers
Siddharth Maharana, Sabyasachi Chattopadhyay, Matthew Bershady
Most optical spectropolarimeters built to date operate as long-slit or point-source instruments; they are inefficient for observations of extended objects such as galaxies and nebu…
The first degree-scale starlight-polarization-based tomography map of the magnetized interstellar medium
V. Pelgrims, N. Mandarakas, R. Skalidis +21
We present the first degree-scale tomography map of the dusty magnetized interstellar medium (ISM) from stellar polarimetry and distance measurements. We used the RoboPol polarimet…
Spectropolarimeter on a 2--4 m class telescope and proposed science cases
Archana Soam, Siddharth Maharana, B-G Andersson +1
We propose a spectropolarimeter a covering wavelength range of 3200--7000 Å [3200Å chosen as lower limit to go to the atmospheric cut-off. It's ``needed" for some Serkowski curves…
Zero-polarization candidate regions for calibration of wide-field optical polarimeters
N. Mandarakas, G. V. Panopoulou, V. Pelgrims +14
Context. Calibration of optical polarimeters relies on the use of stars with negligible polarization (unpolarized standard stars) for determining the instrumental polarization zero…
The RoboPol sample of optical polarimetric standards
D. Blinov, S. Maharana, F. Bouzelou +34
Optical polarimeters are typically calibrated using measurements of stars with known and stable polarization parameters. However, there is a lack of such stars available across the…
Bright-Moon Sky as a Wide-Field Linear Polarimetric Flat Source for Calibration
S. Maharana, S. Kiehlmann, D. Blinov +20
Next-generation wide-field optical polarimeters like the Wide-Area Linear Optical Polarimeters (WALOPs) have a field of view (FoV) of tens of arcminutes. For efficient and accurate…
WALOP-South: A Four-Camera One-Shot Imaging Polarimeter for PASIPHAE Survey. Paper II -- Polarimetric Modelling and Calibration
Siddharth Maharana, Ramya M. Anche, A. N. Ramaprakash +22
The Wide-Area Linear Optical Polarimeter (WALOP)-South instrument is an upcoming wide-field and high-accuracy optical polarimeter to be used as a survey instrument for carrying out…
Starlight-polarization-based tomography of the magnetized interstellar medium: PASIPHAE's line-of-sight inversion method
V. Pelgrims, G. V. Panopoulou, K. Tassis +20
We present the first Bayesian method for tomographic decomposition of the plane-of-sky orientation of the magnetic field with the use of stellar polarimetry and distance. This stan…
WALOP-South: A wide-field one-shot linear optical polarimeter for PASIPHAE survey
Siddharth Maharana, John A. Kypriotakis, A. N. Ramaprakash +20
WALOP (Wide-Area Linear Optical Polarimeter)-South, to be mounted on the 1m SAAO telescope in South Africa, is first of the two WALOP instruments currently under development for ca…
WALOP-South: A Four Camera One Shot Imaging Polarimeter for PASIPHAE Survey. Paper I -- Optical Design
Siddharth Maharana, John A. Kypriotakis, A. N. Ramaprakash +17
The WALOP-South instrument will be mounted on the 1 m SAAO telescope in South Africa as part of the PASIPHAE program to carry out a linear imaging polarization survey of the Galact…
RoboPol: AGN polarimetric monitoring data
D. Blinov, S. Kiehlmann, V. Pavlidou +29
We present uniformly reprocessed and re-calibrated data from the RoboPol programme of optopolarimetric monitoring of active galactic nuclei (AGN), covering observations between 201…
RoboPol: A four-channel optical imaging polarimeter
A. N. Ramaprakash, C. V. Rajarshi, H. K. Das +30
We present the design and performance of RoboPol, a four-channel optical polarimeter operating at the Skinakas Observatory in Crete, Greece. RoboPol is capable of measuring both re…
PASIPHAE: A high-Galactic-latitude, high-accuracy optopolarimetric survey
Konstantinos Tassis, Anamparambu N. Ramaprakash, Anthony C. S. Readhead +13
PASIPHAE (the Polar-Areas Stellar Imaging in Polarization High-Accuracy Experiment) is an optopolarimetric survey aiming to measure the linear polarization from millions of stars,…
RoboPol: Connection between optical polarization plane rotations and gamma-ray flares in blazars
D. Blinov, V. Pavlidou, I. Papadakis +21
We use results of our 3 year polarimetric monitoring program to investigate the previously suggested connection between rotations of the polarization plane in the optical emission…