Professor Gordon Stacey
Astronomical Instrumentation, Extragalactic Astronomy, Far-IR Spectroscopy
ZEUS-2: The high Redshift(z) Early Universe Spectrometer , AO-40: Phased Array Feed for Arecibo Observatory
Amit is a 5th year grad student interested primarily in radio and sub-mm studies of galaxies in the Early Universe, using novel instrumentation. He is a part of the Submillimeter Astrophysics and Instrumentation group studying far infrared and submm atomic and molecular lines to characterize the interstellar medium in galaxies. He has helped build the second generation Redshift(z) and Early Universe Spectrometer (ZEUS-2) implementing the 215/645/850um array. ZEUS-2 is a PI instrument deployed (now 3 annual runs) at the Atacama Pathfinder Experiment (APEX) Telescope at the Chilean Altiplano.
His work focuses on spectral line studies of neutral and ionized ISM at high redshifts. ZEUS-2 is undertaking the first survey of [OIII] and [NII] lines at high redshift which will provide constraints on star formation rates in some of the brightest galaxies in the early Universe. Along with ZEUS-2, data from radio and submm facilities like EVLA, ALMA and Herschel Space Telescope - we aim to study unobscured tracers of ongoing starbursts to constrain massive star formation, ionized gas masses and attempt to study metallicity dependence of emission line diagnostics over cosmic time. These observations will help us understand the hierarchical galaxy evolution model and star formation activity.
He's been a part of the team that built a prototype cryogenic L-Band Phased Array Feed (PAF) for Arecibo Observatory. PAFs offer ~10x faster survey speeds at comparable or greater bandwidth as compared to current instrumentation. However, the challenge of getting all the pieces to work perfectly together is an exciting problem! To implement the idea of Build Your Own Beam (BYOB) on the sky, requires accurate sampling of both, phase and amplitude of the incident field over the entire field of view. This is pushing the limits on currently available data acquisition, conversion and processing hardware. Its an amalgamation of precise Cryogenic design, RF electronics and Digital Signal Processing techniques. And, it makes perfect sense to put it on Arecibo instead of an interferometric array - managing good resolution without compromising on the sensitivity!
Amit was born and brought up in Central India, in a city of lakes, Bhopal. He lived right next to the Arabian Sea (literally) at the National Institute of Technology Karnataka, Surathkal from where he graduated with a B.Tech in Information Technology (2005-2009). He moved to Cornell's School of Electrical and Computer Engineering to finish his Masters (2010). In a very clichéd but happily true sense of pursuing what he loved the most, he started grad school in Astronomy at Cornell (2011-). He enjoys the weather and the scenery of the Fingerlakes region while travelling every so often to his wife at the foothills of Mt. Hood in the Pacific Northwest.
A. Vishwas, C. Ferkinhoff, S. Parshley, T. Nikola, G. Stacey et al, ZEUS-2: on-sky performance, integration of 215/645 micron TES bolometer arrays, an optimized diffraction grating and science results. SPIE 2016 (in prep)
G. Cortes-Medellin, A. Vishwas, S. C. Parshley, D. B. Campbell, P. Perilatt, R. Black, J. Brady, K. F. Warnick, B. D. Jeffs, A Fully Cryogenic Phased Array Camera for Radio Astronomy, IEEE Transactions on Antennas and Propagation, vol. 63, no. 6, pp. 2471-2481, June 2015
G. Cortes-Medellin, S. Parshley, A. Vishwas, D. B. Campbell, Fully cryogenic phased array prototype camera for the Arecibo radio telescope, SPIE 2014
G. Cortes-Medellin, G. Rajagopalan, P. Perillat, A. Vishwas, K. F. Warnick et al, Field of view characterization of Arecibo radio telescope with a phased array feed. IEEE APS/URSI, 2011