M. Meixner
A5026218827- Stellar, planetary, and galactic studies
- Astrophysics and Star Formation Studies
- Astronomy and Astrophysical Research
- Gamma-ray bursts and supernovae
- Astro and Planetary Science
- Astronomical Observations and Instrumentation
- Galaxies: Formation, Evolution, Phenomena
- Astrophysical Phenomena and Observations
- Spectroscopy and Laser Applications
- Adaptive optics and wavefront sensing
- Atmospheric Ozone and Climate
- Vehicle emissions and performance
- Molecular Spectroscopy and Structure
- Space Exploration and Technology
- Astrophysics and Cosmic Phenomena
- Superconducting and THz Device Technology
- Calibration and Measurement Techniques
- History and Developments in Astronomy
- Scientific Research and Discoveries
- Plant tissue culture and regeneration
- Pulsars and Gravitational Waves Research
- Geophysics and Gravity Measurements
- Chromosomal and Genetic Variations
- Planetary Science and Exploration
- Semiconductor Quantum Structures and Devices
Space Telescope Science Institute
2015-2024
Jet Propulsion Laboratory
2023-2024
Johns Hopkins University
2014-2024
Ames Research Center
2021-2024
Amedes Genetics (Germany)
2019-2023
Bloomberg (United States)
2013-2022
Michigan Science Center
2009-2022
Goddard Space Flight Center
2015-2021
Universities Space Research Association
2021
L3Harris (United States)
2019-2021
We are performing a uniform and unbiased, ~7x7 degrees imaging survey of the Large Magellanic Cloud (LMC), using IRAC MIPS instruments on board Spitzer Space Telescope in order to agents galaxy's evolution (SAGE), interstellar medium (ISM) stars LMC. The detection diffuse ISM with column densities >1.2x10^21 H cm^-2 permits detailed studies dust processes ISM. SAGE's point source sensitivity enables complete census newly formed masses >3 solar that will determine current star formation rate...
MIRI (the Mid-Infrared Instrument for the James Webb Space Telescope [JWST]) operates from 5 to 28.5 μm and combines over this range: (1) unprecedented sensitivity levels; (2) subarcsecond angular resolution; (3) freedom atmospheric interference; (4) inherent stability of observing in space; (5) a suite versatile capabilities including imaging, low- medium-resolution spectroscopy (with an integral field unit), coronagraphy. We illustrate potential uses unique combination with various science...
The large amount of dust produced by this supernova may help explain the observed in young galaxies.
Abstract The Mid-Infrared Instrument (MIRI) extends the reach of James Webb Space Telescope (JWST) to 28.5 μ m. It provides subarcsecond-resolution imaging, high sensitivity coronagraphy, and spectroscopy at resolutions λ /Δ ∼ 100–3500, with high-resolution mode employing an integral field unit provide spatial data cubes. resulting broad suite capabilities will enable huge advances in studies over this wavelength range. This overview describes history acquiring capability for JWST. discusses...
The nearby Supernova 1987A was accompanied by a burst of neutrino emission, which indicates that compact object (a neutron star or black hole) formed in the explosion. There has been no direct observation this object. In work, we observe supernova remnant with JWST spectroscopy finding narrow infrared emission lines argon and sulphur. line is spatially unresolved blueshifted velocity relative to rest frame. We interpret as gas illuminated source ionizing photons located close center...
The importance of COVID-19 surveillance from wastewater continues to grow since case-based in the general population has been scaled back world-wide. In Berlin, Germany, quantitative and genomic monitoring for SARS-CoV-2 is performed three treatment plants (WWTP) covering 84% December 2021. Omicron sublineage JN.1 (B.2.86.1.1), was first identified on 22 October 2023 rapidly became dominant sublineage. This change accompanied by a parallel still ongoing increase notification-based...
Aims: In this paper, we perform detailed modelling of the Spitzer and Herschel observations LMC, in order to: (i) systematically study uncertainties biases affecting dust mass estimates; to (ii) explore peculiar ISM properties LMC. Methods: To achieve these goals, have modelled spatially resolved SEDs with two alternate grain compositions, impact different submillimetre opacities on mass. We rigorously propagated observational errors (noise calibration) through entire fitting process, derive...
We present ∼1000 new candidate Young Stellar Objects (YSOs) in the Large Magellanic Cloud selected from Spitzer Space Telescope data, as part of Surveying Agents a Galaxy's Evolution (SAGE) Legacy program. The YSOs, detected by their excess infrared (IR) emission, represent early stages evolution, still surrounded disks and/or infalling envelopes. Previously, fewer than 20 such YSOs were known. SAGE Point Source Catalog regions color–magnitude space least confused with other IR-bright...
We report on an analysis of the gas and dust budget in interstellar medium (ISM) Large Magellanic Cloud (LMC). Recent observations from Spitzer Space Telescope enable us to study mid-infrared excess asymptotic giant branch (AGB) stars LMC. This is first time we can quantitatively assess input AGB over a complete galaxy, fully based observations. The integrated mass-loss rate all intermediate high carbon-rich candidates LMC 8.5x10^-3 solar mass per year, up 2.1x10^-2 year. number could be...
We present a catalog of 1750 massive stars in the Large Magellanic Cloud (LMC), with accurate spectral types compiled from literature, and photometric for subset 1268 these stars, goal exploring their infrared properties. The consists counterparts Spitzer SAGE survey database, which we uniform photometry 0.3 to 24 μm UBVIJHKs+IRAC+MIPS24 bands. resulting color–magnitude diagrams illustrate that supergiant B[e], red supergiant, luminous blue variable (LBV) are among brightest point sources...
We present late-time optical and mid-infrared observations of the Type II supernova 2003gd in galaxy NGC 628. Mid-infrared excesses consistent with cooling dust ejecta are observed 499 to 678 days after outburst accompanied by increasing extinction growing asymmetries emission-line profiles. Radiative-transfer models show that up 0.02 solar masses has formed within ejecta, beginning as early 250 outburst. These formation can be efficient massive-star supernovae could have been major...
Color-magnitude diagrams (CMDs) are presented for the Spitzer SAGE (Surveying Agents of a Galaxy's Evolution) survey Large Magellanic Cloud (LMC). IRAC and MIPS 24 μm epoch 1 data presented. These represent deepest, widest mid-infrared CMDs their kind ever produced in LMC. Combined with Two Micron All Sky Survey, used to delineate evolved stellar populations LMC, as well Galactic foreground extragalactic background populations. Some 32,000 stars brighter than tip red giant branch identified....
We present new Herschel photometric and spectroscopic observations of Supernova 1987A, carried out in 2012. Our dedicated measurements provide 70 micron data improved imaging quality at 100 160 compared to previous 2010. spectra show only weak CO line emission, an upper limit for the 63 [O I] flux, eliminating possibility that contaminations distort previously estimated dust mass. The far-infrared spectral energy distribution (SED) is well fitted by thermal emission from cold dust. newly...
The Mid-InfraRed Instrument (MIRI) on the James Webb Space Telescope (JWST) provides measurements over wavelength range 5 to 28.5 μm. MIRI has, within a single "package," four key scientific functions: photometric imaging, coronagraphy, single-source low-spectral resolving power (R ∼ 100) spectroscopy, and medium-resolving 1500 3500) integral field spectroscopy. An associated cooler system maintains at its operating temperature of < 6.7 K. This paper describes driving principles behind...
The goal of this paper is to present the results a preliminary analysis extended infrared (IR) emission by dust in interstellar medium (ISM) Large Magellanic Cloud (LMC). We combine Spitzer Surveying Agents Galaxy Evolution (SAGE) and Infrared Astronomical Satellite (IRAS) data correlate with gas tracers H i, CO, Hα. global as well detailed modeling spectral energy distribution (SED) few selected regions. Extended associated neutral, molecular, diffuse ionized phases ISM detected at all IR...
We investigate the infrared (IR) properties of cool, evolved stars in Small Magellanic Cloud (SMC), including red giant branch (RGB) and dust-producing supergiant (RSG) asymptotic (AGB) using observations from Spitzer Space Telescope Legacy program entitled: "Surveying Agents Galaxy Evolution Tidally-stripped, Low Metallicity SMC", or SAGE-SMC. The survey includes, for first time, full spatial coverage SMC bar, wing, tail regions at wavelengths (3.6 - 160 microns). identify a combination...
The dust properties in the Large and Small Magellanic clouds (LMC/SMC) are studied using HERITAGE Herschel Key Project photometric data five bands from 100 to 500 μm. Three simple models of emission were fit observations: a single temperature blackbody modified by power-law emissivity (SMBB), broken (BEMBB), two blackbodies with different temperatures, both same (TTMBB). Using these models, we investigate origin submillimeter excess, defined as above that expected SMBB observations <200 We...
The Small Magellanic Cloud (SMC) provides a unique laboratory for the study of lifecycle dust given its low metallicity (~1/5 solar) and relative proximity (~60 kpc). This motivated SAGE-SMC (Surveying Agents Galaxy Evolution in Tidally-Stripped, Low Metallicity Cloud) Spitzer Legacy program with specific goals studying amount type present interstellar medium, sources winds evolved stars, how much is consumed star formation. mapped full SMC (30 sq. deg.) including Body, Wing, Tail 7 bands...
We present an overview of the HERschel Inventory The Agents Galaxy Evolution (HERITAGE) in Magellanic Clouds project, which is a Herschel Space Observatory open time key program. mapped Large Cloud (LMC) and Small (SMC) at 100, 160, 250, 350, 500 μm with Spectral Photometric Imaging Receiver (SPIRE) Photodetector Array Camera Spectrometer (PACS) instruments on board using SPIRE/PACS parallel mode. overriding science goal HERITAGE to study life cycle matter as traced by dust LMC SMC....
Supernova (SN) explosions are crucial engines driving the evolution of galaxies by shock heating gas, increasing metallicity, creating dust, and accelerating energetic particles. In 2012 we used Atacama Large Millimeter/Submillimeter Array to observe SN 1987A, one best-observed supernovae since invention telescope. We present spatially resolved images at 450um, 870um, 1.4mm, 2.8mm, an important transition wavelength range. Longer emission is dominated synchrotron radiation from...
The spatial variations of the gas-to-dust ratio (GDR) provide constraints on chemical evolution and lifecycle dust in galaxies. We examine relation between gas at 10–50 pc resolution Large Small Magellanic Clouds (LMC SMC) based Herschel far-infrared (FIR), H i 21 cm, CO, Hα observations. In diffuse atomic interstellar medium (ISM), we derive GDR as slope dust–gas find GDRs 380 3 LMC, 1200 120 SMC, not including helium. atomic-to-molecular transition is located surface densities 0.05 M☉ pc−2...
We estimate the total dust input from cool evolved stars in Small Magellanic Cloud (SMC), using 8 micron excess emission as a proxy for dust-production rate. find that Asymptotic Giant Branch (AGB) and red supergiant (RSG) produce (8.6-9.5) x 10^7 solar masses per year of dust, depending on fraction far-infrared sources belong to star population (with 10%-50% uncertainty individual rates). RSGs contribute least (<4%), while carbon-rich AGB (especially so-called "extreme" stars) account...
We have carried out 13CO(J = 2–1) observations of the active star-forming region N159 west in Large Magellanic Cloud with ALMA. found that CO distribution at a sub-parsec scale is highly elongated small width. These clouds called "filaments" show straight or curved distributions typical width 0.5–1.0 pc and length 5–10 pc. All known infrared young stellar objects are located toward filaments. broad wings two molecular outflows high-mass stars N159W-N N159W-S, whose dynamical timescale ∼104...
We report the results from an optical imaging survey of proto-planetary nebula candidates using Hubble Space Telescope (HST). The goals were to image low surface brightness reflection nebulosities around nebulae and investigate distribution circumstellar dust, which scatters star light central post-asymptotic giant branch creates nebulosities. exploited high resolving power wide dynamic range HST detected in 21 27 sources. reduced deconvolved images are presented along with photometric...