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Ninkov, Zoran

Publications and source records attributed to Ninkov, Zoran.

7 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Illuminating Galaxy Evolution at Cosmic Noon with ISCEA: the Infrared Satellite for Cosmic Evolution Astrophysics

ISCEA (Infrared Satellite for Cosmic Evolution Astrophysics) is a small astrophysics mission whose Science Goal is to discover how galaxies evolved in the cosmic web of dark matter at cosmic noon. Its Science Objective is to determine the history of star formation and its quenching in galaxies as a function of local density and stellar mass when the Universe was 3-5 Gyrs old (1.2 10 Mpc in each of 50 protocluster (cluster and cosmic web) fields at 1.2 < z < 2.1. ISCEA measures the star formation quenching factor in those fields, and galaxy kinematics with a precision < 50 km/s to deduce the 3D spatial distribution in each field. ISCEA will transform our understanding of galaxy evolution at cosmic noon. ISCEA is a small satellite observatory with a 30cm equivalent diameter aperture telescope with a FoV of 0.32 deg^2, and a multi-object spectrograph with a digital micro-mirror device (DMD) as its programmable slit mask. ISCEA will obtain spectra of 1000 galaxies simultaneously at an effective resolving power of R=1000, with 2.8"x2.8" slits, over the NIR wavelength range of 1.1 to 2.0 microns, a regime not accessible from the ground without large gaps in coverage. ISCEA will achieve a pointing accuracy of <= 2" FWHM over 200s. ISCEA will be launched into a Low Earth Orbit, with a prime mission of 2.5 years. ISCEA's space-qualification of DMDs opens a new window for spectroscopy from space, enabling revolutionary advances in astrophysics.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2019

ATLAS probe: Breakthrough science of galaxy evolution, cosmology, Milky Way, and the Solar System

Astrophysics Telescope for Large Area Spectroscopy Probe is a concept for a National Aeronautics and Space Administration probe-class space mission that will achieve ground-breaking science in the fields of galaxy evolution, cosmology, Milky Way, and the Solar System. It is the follow-up space mission to Wide Field Infrared Survey Telescope (WFIRST), boosting its scientific return by obtaining deep 1–4 μm slit spectroscopy for ~70% of all galaxies imaged by the ~2 000 deg 2 WFIRST High Latitude Survey at z > 0.5. Astrophysics Telescope for Large Area Spectroscopy will measure accurate and precise redshifts for ~200 M galaxies out to z < 7, and deliver spectra that enable a wide range of diagnostic studies of the physical properties of galaxies over most of cosmic history. Astrophysics Telescope for Large Area Spectroscopy Probe and WFIRST together will produce a 3D map of the Universe over 2 000 deg 2 , the definitive data sets for studying galaxy evolution, probing dark matter, dark energy and modifications of General Relativity, and quantifying the 3D structure and stellar content of the Milky Way. Astrophysics Telescope for Large Area Spectroscopy Probe science spans four broad categories: (1) Revolutionising galaxy evolution studies by tracing the relation between galaxies and dark matter from galaxy groups to cosmic voids and filaments, from the epoch of reionisation through the peak era of galaxy assembly; (2) Opening a new window into the dark Universe by weighing the dark matter filaments using 3D weak lensing with spectroscopic redshifts, and obtaining definitive measurements of dark energy and modification of General Relativity using galaxy clustering; (3) Probing the Milky Way’s dust-enshrouded regions, reaching the far side of our Galaxy; and (4) Exploring the formation history of the outer Solar System by characterising Kuiper Belt Objects. Astrophysics Telescope for Large Area Spectroscopy Probe is a 1.5 m telescope with a field of view of 0.4 deg 2 , and uses digital micro-mirror devices as slit selectors. It has a spectroscopic resolution of R = 1 000, and a wavelength range of 1–4 μm. The lack of slit spectroscopy from space over a wide field of view is the obvious gap in current and planned future space missions; Astrophysics Telescope for Large Area Spectroscopy fills this big gap with an unprecedented spectroscopic capability based on digital micro-mirror devices (with an estimated spectroscopic multiplex factor greater than 5 000). Astrophysics Telescope for Large Area Spectroscopy is designed to fit within the National Aeronautics and Space Administration probe-class space mission cost envelope; it has a single instrument, a telescope aperture that allows for a lighter launch vehicle, and mature technology (we have identified a path for digital micro-mirror devices to reach Technology Readiness Level 6 within 2 yr). In conclusion, Astrophysics Telescope for Large Area Spectroscopy Probe will lead to transformative science over the entire range of astrophysics: from galaxy evolution to the dark Universe, from Solar System objects to the dusty regions of the Milky Way

79 ASTRONOMY AND ASTROPHYSICS↗
NASA NTRS2016

Galaxy Evolution Spectroscopic Explorer: Scientific Rationale

GESE is a mission concept consisting of a 1.5-m space telescope and UV multi-object slit spectrograph designed to help understand galaxy evolution in a critical era in the history of the universe, where the rate of star-formation stopped increasing and started to decline. To isolate and identify the various processes driving the evolution of these galaxies, GESE will obtain rest-frame far-UV spectra of 100,000 galaxies at redshifts, z approximately 1-2. To obtain such a large number of spectra, multiplexing over a wide field is an absolute necessity. A slit device such as a digital micro-mirror device (DMD) or a micro-shutter array (MSA) enables spectroscopy of a hundred or more sources in a single exposure while eliminating overlapping spectra of other sources and blocking unwanted background like zodiacal light. We find that a 1.5-m space telescope with a MSA slit device combined with a custom orbit enabling long, uninterrupted exposures (approximately 10 hr) are optimal for this spectroscopic survey. GESE will not be operating alone in this endeavor. Together with x-ray telescopes and optical/near-IR telescopes like Subaru/Prime Focus Spectrograph, GESE will detect "feedback" from young massive stars and massive black holes (AGN's), and other drivers of galaxy evolution.

digital micro-mirror device (DMD)↗
NASA NTRS2016

Optical Evaluation of Digital Micromirror Devices (DMDs) with UV-Grade Fused Silica, Sapphire, and Magnesium Fluoride Windows and Longterm Reflectance of Bare Devices

Digital micromirror devices (DMDs) are commercial micro-electromechanical systems, consisting of millions of mirrors which can be individually addressed and tilted into one of two states (+/-12deg). These devices were developed to create binary patterns in video projectors, in the visible range. Commercially available DMDs are hermetically sealed and extremely reliable. Recently, DMDs have been identified as an alternative to microshutter arrays for space-based multi-object spectrometers (MOS). Specifically, the MOS at the heart of the proposed Galactic Evolution Spectroscopic Explorer (GESE) uses the DMD as a reprogrammable slit mask. Unfortunately, the protective borosilicate windows limit the use of DMDs in the UV and IR regimes, where the glass has insufficient throughput. In this work, we present our efforts to replace standard DMD windows with custom windows made from UV-grade fused silica, low-absorption optical sapphire (LAOS) and magnesium fluoride (MgF2). We present transmission measurements of the antireflection coated windows and the reflectance of bare (window removed) DMDs. Furthermore, we investigated the long-term stability of the DMD reflectance and experiments for coating DMD active area with a layer of pure aluminum (Al) to boost reflectance performance in the UV spectral range (200−400 nm).

reflectance↗
NASA NTRS2016

Optical Evaluation of DMDs with UV-Grade FS, Sapphire, MgF2 Windows and Reflectance of Bare Devices

Digital Micro-mirror Devices (DMDs) have been identified as an alternative to microshutter arrays for space-based multi-object spectrometers (MOS). Specifically, the MOS at the heart of a proposed Galactic Evolution Spectroscopic Explorer (GESE) that uses the DMD as a reprogrammable slit mask. Unfortunately, the protective borosilicate windows limit the use of DMDs in the UV and IR regimes, where the glass has insufficient throughput. In this work, we present our efforts to replace standard DMD windows with custom windows made from UV-grade fused silica, Low Absorption Optical Sapphire (LAOS) and magnesium fluoride. We present reflectance measurements of the antireflection coated windows and a reflectance study of the DMDs active area (window removed). Furthermore, we investigated the long-term stability of the DMD reflectance and recoating device with fresh Al coatings.

Quijada, Manuel A.↗
NASA NTRS1996

Mineralogy

The power of mineralogical analysis as a descriptive or predictive technique stems from the fact that only a few thousand minerals are known to occur in nature as compared to several hundred thousand inorganic compounds. Further, all of the known minerals have specific stability ranges in pressure, temperature, an composition. A specific knowledge of the mineralogy of a planets surface or interior therefore allows one to characterize the present or past conditions under which the minerals were formed or have existed. For the purposes of this paper, a slightly broader definition of mineralogy was adopted by including not only crystalline materials found on planetary surfaces, but also ices and classes that can benefit from in situ types of analyses. Both visual examination and the various spectroscopies available for robotic probes to planetary surfaces are discussed.

Dyar, M. Darby↗