A5040030765- Astronomy and Astrophysical Research
- Adaptive optics and wavefront sensing
- Astrophysics and Cosmic Phenomena
- Stellar, planetary, and galactic studies
- Advanced optical system design
- Gamma-ray bursts and supernovae
- Astronomical Observations and Instrumentation
- Particle Accelerators and Free-Electron Lasers
- CCD and CMOS Imaging Sensors
- Astrophysical Phenomena and Observations
- Advanced Fiber Optic Sensors
- Calibration and Measurement Techniques
- Semiconductor Lasers and Optical Devices
- Photonic and Optical Devices
- Galaxies: Formation, Evolution, Phenomena
- Advanced Measurement and Metrology Techniques
- Particle Detector Development and Performance
- Optical Coatings and Gratings
- Advanced Optical Sensing Technologies
- Laser Design and Applications
- Nuclear physics research studies
- Artificial Intelligence in Games
- Laser-Plasma Interactions and Diagnostics
- Spacecraft Design and Technology
- Optical Polarization and Ellipsometry
South African Radio Astronomy Observatory
2020-2024
University of Wisconsin–Madison
2020-2022
Astronomical Observatory
2022
Inter-University Centre for Astronomy and Astrophysics
2014-2018
Trinity College Dublin
2008
University of Michigan
2008
Abstract We present results from a high-cadence multiwavelength observational campaign of the enigmatic changing-look active galactic nucleus 1ES 1927+654 2022 May to 2024 April, coincident with an unprecedented radio flare (an increase in flux by factor ∼60 over few months) and emergence spatially resolved jet at 0.1–0.3 pc scales. Companion work has also detected recurrent quasi-periodic oscillation (QPO) 2–10 keV band increasing frequency (1–2 mHz) same period. During this time, soft...
We present results from a high cadence multi-wavelength observational campaign of the enigmatic changing look AGN 1ES 1927+654 May 2022- April 2024, coincident with an unprecedented radio flare (an increase in flux by factor $\sim 60$ over few months) and emergence spatially resolved jet at $0.1-0.3$ pc scales (Meyer et al. 2024). Companion work has also detected recurrent quasi-periodic oscillation (QPO) $2-10$ keV band increasing frequency ($1-2$ mHz) same period (Masterson al., 2025)....
ABSTRACT We have re-observed $\rm \sim$40 low-inclination, star-forming galaxies from the MaNGA survey (σ ∼ 65 km s−1) at ∼6.5 times higher spectral resolution 10 using HexPak integral field unit on WIYN 3.5-m telescope. The aim of these observations is to calibrate MaNGA’s instrumental and characterize turbulence in warm interstellar medium ionized galactic outflows. Here we report results for Hα region as they pertain calibration resolution. Remarkably, find that previously reported...
Abstract 1ES1927+654 is a nearby active galactic nucleus (AGN) that has shown an enigmatic outburst in optical/UV followed by X-rays, exhibiting strange variability patterns at timescales of months to years. Here we report the unusual X-ray, UV, and radio source its postflare state (2022 January–2023 May). First, detect increase soft X-ray (0.3–2 keV) flux from 2022 May 2023 almost factor 5, which call bright state. The hard 2–10 keV increased 2, while UV density did not show any significant...
Devasthal Optical Telescope Integral Field Spectrograph (DOTIFS) is a new multi-object (IFS) being designed and fabricated by the Inter-University Center for Astronomy Astrophysics (IUCAA), Pune, India, Cassegrain side port of 3.6m Telescope, (DOT) constructed Aryabhatta Research Institute Observational Sciences (ARIES), Nainital. It mainly to study physics kinematics ionized gas, star formation H II regions in nearby galaxies. novel instrument terms multi-IFU, built deployment system, high...
The Sloan Digital Sky Survey V (SDSS-V) is an all-sky spectroscopic survey of <6 million objects, designed to decode the history Milky Way, reveal inner workings stars, investigate origin solar systems, and track growth supermassive black holes across Universe. Local Volume Mapper (LVM) a facility provide contiguous 2,500 deg2 integral-field over 3.5 year period from Las Campanas Observatory in Chile. In this paper we overview status update for LVM instrument (hereafter LVM-I). Each unit's...
A generic fiber positioning strategy and a fabrication path are presented for microlens-fiber-coupled integral field units. It is assumed that microlens-produced micro-images carried to the spectrograph input through step-index,multi-mode fiber, but our results apply micro-pupil reimaging applications as well. Considered performance trades between filling percentage of core with micro-image versus throughput observing efficiency.A merit function defined product transmission efficiency...
In order to run the large format detector arrays and mosaics that are required by most astronomical instruments, readout electronic controllers which can process multiple CCD outputs simultaneously at high speeds low noise levels. These need be modular configurable, should able types cater a wide variety of requirements. IUCAA Digital Sampler Array Controller (IDSAC), is generic based on fully scalable architecture adequately flexible powerful enough control detectors used in ground...
Long-slit astronomical spectroscopy has various limitations when dealing with optimum slit width, atmospheric dispersion, extended source spectroscopy, etc. to name a few. Most of these issues can be solved by the use optical fibers as light carrier from telescope focal plane spectrograph. The approach is technically and scientifically flexible in terms instrument modularity target acquisition. Implementation Integral Field Unit (IFU) provides continuous sampling objects distinct advantage...
We have re-observed $\rm\sim$40 low-inclination, star-forming galaxies from the MaNGA survey ($\upsigma\sim65$~\kms) at $\sim$6.5 times higher spectral resolution ($\upsigma\sim10$~\kms) using HexPak integral field unit on WIYN 3.5m telescope. The aim of these observations is to calibrate MaNGA's instrumental and characterize turbulence in warm interstellar medium ionized galactic outflows. Here we report results for H$\rm\upalpha$ region as they pertain calibration resolution. Remarkably,...
The performance of fiber-fed astronomical spectrographs is highly influenced by the properties fibers. near-field and far-field scrambling characteristics have a profound impact on line spread function (LSF) spectra. Focal ratio degradation (FRD) influences output beam size, thereby affecting throughput, as well size collimator dispersion elements. While previous research has indicated that these depend shape fiber core showed non-circular fibers can yield uniform scrambling, result remains...
Most optical spectropolarimeters built to date operate as long-slit or point-source instruments; they are inefficient for observations of extended objects such galaxies and nebulae. 2D spectropolarimetry technique development is a major challenge in astronomical instrumentation. At the South African Astronomical Observatory (SAAO) FiberLab, we developing capable Integral Field front-end called FiberPol(-6D) existing SpUpNIC spectrograph on SAAO 1.9 m telescope. general purpose 2 arc-minute...
We present fore-optics and calibration unit design of Devasthal Optical Telescope Integral Field Spectrograph (DOTIFS). DOTIFS is designed to modify the focal ratio light match its plate scale physical size Units (IFUs). The also delivers a telecentric beam IFUs on telescope plane. There part which combined with have compact system. use Xenon-arc lamp as continuum source Krypton/Mercury-Neon lamps wavelength sources. Fore-optics shares two optical lenses maintain compactness overall...
The IUCAA digital sampling array controller (IDSAC) is a flexible and generic yet powerful CCD that can handle wide range of scientific detectors. Based on an easily scalable modular backplane architecture consisting single board controllers (SBC), IDSAC control large detector arrays mosaics. Each the SBCs offers full functionality required to independently. be cold swapped without need reconfigure them. also available in backplane-less architecture. SBC data from up four video channels with...
We present the design of prototype telescope and spectrograph system for Affordable Multiple Aperture Spectroscopy Explorer (AMASE) project. AMASE is a planned project that will pair 100 identical multi-fiber spectrographs with large array telephoto lenses to achieve area integral field spectroscopy survey sky at spatial resolution half an arcminute spectral R=15,000, covering important emission lines in optical studying ionized gas Milky Way beyond. The be enabled by significant reduction...
As a part of design study for the On-Instrument Low Order Wave-front Sensor (OIWFS) TMT Infra-Red Imaging Spectrograph (IRIS), we recently evaluated noise performance detector control system consisting IUCAA SIDECAR DRIVE ELECRONICS CONTROLLER (ISDEC), ASIC and HAWAII-2RG (H2RG) MUX. To understand improve this to serve as near infrared wavefront sensor, implemented new read out modes like multiple regions interest with differential multi-accumulate readout schemes detector. In system,...
Many sets of polarization evolution equations have been suggested to describe the method buildup by spin filtering in storage rings. In this paper a generic system describing is derived and solved, then we compare contrast other descriptions appearing literature. This interest projects planning produce polarized antiproton beam filtering, any project utilizing The physical processes responsible for are analysed their contributions dynamics highlighted. It hoped that will shed light on some confusion
Devasthal Optical Telescope Integral Field Spectrograph (DOTIFS) is a new multi-Integral Unit (IFU) instrument, planned to be mounted on the 3.6m optical telescope in Nainital, India. It has eight identical, fiber-fed spectrographs disperse light coming from 16 IFUs. The produce 2,304 spectra over 370-740nm wavelength range simultaneously with spectral resolution of R=1200-2400. composed all-refractive, allspherical optics designed achieve average 26.0% throughput CCD help high transmission...
We have developed an analytic model for generic image transfer using microlens-coupled fibers to determine the telescope input beam speed that optimizes lenslet clear aperture and minimizes fiber focal-ratio degradation. Assuming are fed at f/3.5 by lenslets, our study shows f/11 is optimum feed a coupled with 100um diameter core. These considerations relevant design of high-efficiency, dedicated survey telescopes employ lenslet-coupled systems.
We describe the optimum telescope focal ratio for a two-element, three-surface, telecentric image-transfer microlens-to-fiber coupled integral field unit within constraints imposed by microoptics fabrication and optical aberrations. create generalized analytical description of parameters from first principles. find that performance, including all aberrations, design constrained an analytic model considering only spherical aberration diffraction matches ± 4 % optimized ray-tracing software...