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Ultraviolet radiation is known to inhibit photosynthesis, induce DNA destruction and cause damage to a wide variety of proteins and lipids. In particular, UV radiation between 200-300 nm becomes energetically very damaging to most of the…

Astrophysics · Physics 2009-11-11 Andrea P. Buccino , Guillermo A. Lemarchand , Pablo J. D. Mauas

High-contrast imaging from space must overcome two major noise sources to successfully detect a terrestrial planet angularly close to its parent star: photon noise from diffracted star light, and speckle noise from star light scattered by…

Astrophysics · Physics 2009-11-13 Pascal J. Borde , Wesley A. Traub

Recent discoveries of young exoplanets within their natal disks offer exciting opportunities to study ongoing planet formation. In particular, a planet's mass accretion rate can be constrained by observing the accretion-induced excess…

The ongoing discovery of exoplanets has sparked significant interest in finding suitable worlds that could potentially support life. Stellar ultraviolet (UV; 100-3000 \AA) radiation may play a crucial role in determining the habitability of…

Solar and Stellar Astrophysics · Physics 2024-11-01 Xue Li , Song Wang , Henggeng Han , Jifeng Liu

The optical vortex coronagraph (OVC) is one of the promising ways for direct imaging exoplanets because of its small inner working angle and high throughput. This paper presents the design and laboratory demonstration performance at 633nm…

Instrumentation and Methods for Astrophysics · Physics 2017-06-14 Chengchao Liu , Deqing Ren , Yongtian Zhu , Jiangpei Dou

For solar-system objects, ultraviolet spectroscopy has been critical in identifying sources for stratospheric heating and measuring the abundances of a variety of hydrocarbon and sulfur-bearing species, produced via photochemical…

In a previous paper, we discussed an original solution to improve the performances of coronagraphs by adding, in the optical scheme, an adaptive hologram removing most of the residual speckle starlight. In our simulations, the detection…

Instrumentation and Methods for Astrophysics · Physics 2011-02-17 Davide Ricci , Hervé Le Coroller , Antoine Labeyrie , Pierre Piron

We present the science case for characterizing the nature of the first stars using the Habitable Worlds Observatory (HWO). High-resolution ultraviolet (UV) spectroscopy with the HWO has the potential to confirm any surviving low-mass…

Instrumentation and Methods for Astrophysics · Physics 2025-09-04 Ian U. Roederer , Rana Ezzeddine , Jennifer S. Sobeck

General arguments for optimized coronagraphy in the search for planets are presented. First, off-axis telescopes provide the best telescopic platforms for use with coronagraphy, and telescope fabrication technology now allows the…

Astrophysics · Physics 2007-05-23 A. T. Tokunaga , C. Ftaclas , J. R. Kuhn , P. Baudoz

The Hubble Space Telescope (HST)/Space Telescope Imaging Spectrograph (STIS) contains the only currently operating coronagraph in space that is not trained on the Sun. In an era of extreme--adaptive-optics--fed coronagraphs, and with the…

Instrumentation and Methods for Astrophysics · Physics 2019-05-17 J. H. Debes , B. Ren , G. Schneider

The challenges of high contrast imaging (HCI) for detecting exoplanets for both ground and space applications can be met with extreme adaptive optics (ExAO), a high-order adaptive optics system that performs wavefront sensing (WFS) and…

Very high dynamical range coronagraphs targeting direct exo-planet detection (10^9 - 10^10 contrast) at small angular separation (few lambda/D units) usually require an input wavefront quality on the order of ten thousandths of wavelength…

Astrophysics · Physics 2009-11-13 J. Nishikawa , L. Abe , N. Murakami , T. Kotani

The Optimal Optical CoronagraphWorkshop at the Lorentz Center in September 2017 in Leiden, the Netherlands gathered a diverse group of 25 researchers working on exoplanet instrumentation to stimulate the emergence and sharing of new ideas.…

Extreme wavefront correction is required for coronagraphs on future space telescopes to reach 1e-8 or better starlight suppression for the direct imaging and characterization of exoplanets in reflected light. Thus, a suite of wavefront…

Observations utilizing the ultraviolet capabilities of the Cosmic Origin Spectrograph (COS) onboard the Hubble Space Telescope are of unique value to the astronomy community. Spectroscopy down to 900 A with COS has enabled new science…

Instrumentation and Methods for Astrophysics · Physics 2024-06-12 Svea Hernandez , Andrei Igoshev , Jo Taylor , David Sahnow , Logan Jones

The plasma thermodynamics in the solar upper atmosphere, particularly in the corona, are dominated by the magnetic field, which controls the flow and dissipation of energy. The relative lack of knowledge of the coronal vector magnetic field…

Solar and Stellar Astrophysics · Physics 2016-06-29 N. E. Raouafi , P. Riley , S. Gibson , S. Fineschi , S. K. Solanki

Extra-solar planets have not been imaged directly with existing ground or space telescopes because they are too faint to be seen against the halo of the nearby bright star. Most techniques being explored to suppress the halo are achromatic,…

Astrophysics · Physics 2009-11-10 Johanan L. Codona , Roger Angel

Transmission spectroscopy of exoplanets is a tool to characterize rocky planets and explore their habitability. Using the Earth itself as a proxy, we model the atmospheric cross section as a function of wavelength, and show the effect of…

Earth and Planetary Astrophysics · Physics 2017-03-23 Y. Betremieux , L. Kaltenegger

I describe the capabilities of the Cosmic Origins Spectrograph, scheduled for May 2009 installation on the Hubble Space Telescope. With a factor-of-ten increase in far-UV throughput for moderate resolution spectroscopy, COS will enable a…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 J. Michael Shull
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