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Analysis of He I 1083 nm Imaging Spectroscopy Using a Spectral Standard

O.V. Malanushenko, H.P. Jones
2004 Solar Physics  
For our example, we find that line widths and central intensity are oppositely correlated in a coronal hole and quiet Sun.  ...  We examine distributions of Doppler velocity and line width as a function of central intensity fcr an active region, filament, quiet Sun, and coronal hole.  ...  Acknowledgements NSO/Kitt Peak data used here are produced cooperatively by NSF/NOAO, NASA/GSFC, and NOAA/SEC. This work was supported by NASA Office of Space Sciences grant 34412-51-14.  ... 
doi:10.1023/b:sola.0000036873.75777.33 fatcat:ehs27xphlndvpjwhaat2q7no4u

Observability of Coronal Heating Processes

P. Venkatakrishnan
1996 International Astronomical Union Colloquium  
A comparison of Hel absorption in quiet and active regions demonstrates the difficulty of interpreting data that connect chromospheric dynamics with coronal heating.  ...  Finally, the implications of the search for observations of coronal heating processes are mentioned.  ...  Hel Absorption and Coronal Heating The observed darkening of active regions in the Hel 1083 nm line and the comparatively low level of its absorption seen in coronal holes seemed to indicate a link between  ... 
doi:10.1017/s0252921100029948 fatcat:ypin6jxxijgsvbyehz3iocwrea

Infrared Solar Physics

Matthew J. Penn
2014 Living Reviews in Solar Physics  
Several avenues of solar physics research exploiting and benefiting from observations at infrared wavelengths from roughly 1000 nm to 12 400 nm are discussed, and the instrument and detector technology  ...  The infrared solar spectrum contains a wealth of physical data about our Sun, and is explored using modern detectors and technology with new ground-based solar telescopes.  ...  Ground-based observations of coronal holes The He i 1083 nm line provides a useful ground-based method for studying coronal features on the disk of the Sun.  ... 
doi:10.12942/lrsp-2014-2 pmid:27194956 pmcid:PMC4841185 fatcat:6yqmat57tbelrgka2pno3h7cfa

Chromospheric Prolateness: Solar Cycle Variations

J. Vilinga, S. Koutchmy, Fr. Auchere, Fr. Baudin, B. Filippov, J-C. Noens
2006 Proceedings of the International Astronomical Union  
However, cool lines like Hα and Ca II lines, do NOT show this Coronal Hole (CH) effect. Coronal lines and HeI (D3; 1083 nm) do show CHs but do not show the prolateness effect.  ...  Coronal X-EUV emissions usually penetrate deep enough into the chromosphere to completely mask this effect on transition region lines and produce the so-called coronal hole effect.  ...  Curves corresponding to the HeI 1083 nm (no prolateness but a CH effect) and to the CaII K line emissions (well pronounced prolateness effect) are shown.  ... 
doi:10.1017/s1743921306001931 fatcat:dzyvc256rjh77n3bi646aksv2e

An Interpretation of the Coronal Holes' Visibility in the Millimeter Wavelength Range

R. Brajša, A. O. Benz, M. Temmer, R. Jurdana-Šepić, B. Šaina, H. Wöhl
2007 Solar Physics  
The observational finding that the average brightness temperature of coronal holes is not much different from the quiet-Sun level (with localized deviations toward higher and lower intensities on the order  ...  Various observations indicate that coronal holes generally appear as low brightness temperature regions (LTRs) in the centimeter and millimeter wavelength ranges.  ...  Sakurai, who kindly provided measurements from the Metsähovi Radio Observatory and Yohkoh-SXT, respectively, and acknowledge the use of complementary data from the Big Bear Solar Observatory and NSO at  ... 
doi:10.1007/s11207-007-9008-4 fatcat:dkx4mchiqbcnhjyzwx33ogpfq4

Proxy-Based Prediction of Solar Extreme Ultraviolet Emission using Deep Learning [article]

Anthony L. Pineci and Peter Sadowski and Eric Gaidos and Xudong Sun
2021 arXiv   pre-print
Here, we evaluate absorption in the near-infrared 1083 nm triplet line of neutral orthohelium as a proxy for extreme ultraviolet (EUV) emission in the 30.4 nm line of He II and 17.1 nm line of Fe IX from  ...  Qualitatively, the model learns the complex spatial correlations between He I absorption and EUV emission has a predictive ability superior to that of a pixel-by-pixel model; it can also distinguish active  ...  DATASETS AND METHODS We used full-disk solar images (i.e., linescanning-based maps) of the He I 1083 nm line strength (i.e., equivalent width) obtained by the Vector SpectroMagnetograph (VSM) at the Synoptic  ... 
arXiv:2103.08887v1 fatcat:ynuli2r23ngx5chtzp5qk7zwny

Solar physics in the 2020s: DKIST, parker solar probe, and solar orbiter as a multi-messenger constellation [article]

V. Martinez Pillet, A. Tritschler, L. Harra, V. Andretta, A. Vourlidas, N. Raouafi, B.L. Alterman, L. Bellot Rubio, G. Cauzzi, S.R. Cranmer, S. Gibson, S. Habbal (+11 others)
2020 arXiv   pre-print
DKIST will join the early science phases of the NASA and ESA Parker Solar Probe and Solar Orbiter encounter missions.  ...  By combining in-situ measurements of the near-sun plasma environment and detail remote observations of multiple layers of the Sun, the three observatories form an unprecedented multi-messenger constellation  ...  of the He I 1083 nm permitted line to infer the three components of the coronal magnetic field.  ... 
arXiv:2004.08632v1 fatcat:igooufoetjcv5cuprz7xn3df5u

Solar Cycle Indices from the Photosphere to the Corona: Measurements and Underlying Physics

Ilaria Ermolli, Kiyoto Shibasaki, Andrey Tlatov, Lidia van Driel-Gesztelyi
2014 Space Science Reviews  
Most of these indices are highly correlated with each other owing to their intrinsic link with the solar magnetism and the dominant eleven year cycle, but their variations may differ in fine details, as  ...  A variety of indices have been proposed in order to represent the many different observables modulated by the solar cycle.  ...  Final acknowledgements go to the many observers and astronomers, both amateur and professional, for performing the regular observations of the solar atmosphere and creating the databases of solar indices  ... 
doi:10.1007/s11214-014-0089-8 fatcat:zbz4utfd45divavvjt23cnplbe

Solar Cycle Indices from the Photosphere to the Corona: Measurements and Underlying Physics [chapter]

Ilaria Ermolli, Kiyoto Shibasaki, Andrey Tlatov, Lidia van Driel-Gesztelyi
2015 Space Sciences Series of ISSI  
Most of these indices are highly correlated with each other owing to their intrinsic link with the solar magnetism and the dominant eleven year cycle, but their variations may differ in fine details, as  ...  A variety of indices have been proposed in order to represent the many different observables modulated by the solar cycle.  ...  Final acknowledgements go to the many observers and astronomers, both amateur and professional, for performing the regular observations of the solar atmosphere and creating the databases of solar indices  ... 
doi:10.1007/978-1-4939-2584-1_4 fatcat:nbks34knvzhx7fb363j55q7vba

Science Requirement Document (SRD) for the European Solar Telescope (EST) (2nd edition, December 2019) [article]

R. Schlichenmaier, R. Erdelyi, E. Khomenko, M. Carlsson, C. Kuckein, A. Ortiz, P.J.A. Simoes Leibniz-Institut für Sonnenphysik Instituto de Astrofisica de Andalucia Departamento de Astrofisica, Universidad de La Laguna SP2RC, University of Sheffield, Max-Planck-Institut für Sonnensystemforschung SUPA School of Physics and Astronomy, University of Glasgow, Astronomical Institute of the Czech Academy of Sciences (+17 others)
2019 arXiv   pre-print
Identifying critical science requirements is one of its main goals. Those requirements will define the capabilities of EST and the post-focus instrument suite.  ...  The goal of the preparatory phase is to accomplish a final design for the telescope and the legal governance structure of EST.  ...  coronal hole boundaries as a function of height.  ... 
arXiv:1912.08650v1 fatcat:hkb47vlltrczbkoslqveztlyca

The Evolution and Space Weather Effects of Solar Coronal Holes [article]

Larisza Diana Krista
2012 arXiv   pre-print
The forecasting of flare and CME related transient geomagnetic storms has become a primary initiative, however, minor magnetic storms caused by coronal holes (CHs) have also proven to be of high importance  ...  This allowed us to further our understanding of CH evolution as a whole.  ...  Figure 1 . 1 KPVT He I 1083 nm spectroheliogram (top, left), EIT 19.5 nm Fe XII emission line image (top, right), the KPVT associated "hand-drawn" coronal hole image (bottom, left), and the automated detection  ... 
arXiv:1210.4475v1 fatcat:hsbygwmgrfcvtoqedljblpywje

Solar weather monitoring

J.-F. Hochedez, A. Zhukov, E. Robbrecht, R. Van der Linden, D. Berghmans, P. Vanlommel, A. Theissen, F. Clette
2005 Annales Geophysicae  
Space Weather nowcasting and forecasting require solar observations because geoeffective disturbances can arise from three types of solar phenomena: coronal mass ejections (CMEs), flares and coronal holes  ...  The objectives of Space Weather require some specific instrumental features, which we list using the experience gained from the daily operations of the Solar Influences Data analysis Centre (SIDC) at the  ...  The authors thank the anonymous referees for their numerous comments and suggestions for improvement. Topical Editor R. J. Forsyth thanks J. M. Kunches and I. G.  ... 
doi:10.5194/angeo-23-3149-2005 fatcat:cwazcpaq4zatthc7n7jhi3q6cy

Magnetic imaging of the outer solar atmosphere (MImOSA)

H. Peter, E. Alsina Ballester, V. Andretta, F. Auchère, L. Belluzzi, A. Bemporad, D. Berghmans, E. Buchlin, A. Calcines, L.P. Chitta, K. Dalmasse, T. del Pino Alemán (+11 others)
2021 Experimental astronomy (Print)  
We suggest a suite of three instruments that far exceed current capabilities in terms of spatial resolution, light-gathering power, and polarimetric performance: (a) A large-aperture UV-to-IR telescope  ...  This mission to measure the magnetic field will finally unlock the driver of the dynamics in the outer solar atmosphere and thereby will greatly advance our understanding of the Sun and the heliosphere  ...  Using lines such as Ca II near 394 nm and 854 nm and He I near 1083 nm, it will explore the magnetic field in the low chromosphere through on-disc measurements.  ... 
doi:10.1007/s10686-021-09774-0 fatcat:4sbhloqiwjflziodizbgxikv64

Magnetic Imaging of the Outer Solar Atmosphere (MImOSA): Unlocking the driver of the dynamics in the upper solar atmosphere [article]

H. Peter, E. Alsina Ballester, V. Andretta, F. Auchere, L. Belluzzi, A. Bemporad, D. Berghmans, E. Buchlin, A. Calcines, L.P. Chitta, K. Dalmasse, T. del Pino Aleman (+11 others)
2021 arXiv   pre-print
We suggest a suite of three instruments that far exceed current capabilities in terms of spatial resolution, light-gathering power, and polarimetric performance: (a) A large-aperture UV-to-IR telescope  ...  This mission to measure the magnetic field will unlock the driver of the dynamics in the outer solar atmosphere and thereby greatly advance our understanding of the Sun and the heliosphere.  ...  II IR (854 nm) He I (1083 nm) He I (1083 nm)  ... 
arXiv:2101.01566v1 fatcat:yvnzyyviibfjpprljqvj5xr6oa

Critical Science Plan for the Daniel K. Inouye Solar Telescope (DKIST)

Mark P. Rast, NSO, DKIST project, and DKIST instrument scientists, Nazaret Bello González, Luis Bellot Rubio, Wenda Cao, Gianna Cauzzi, Edward DeLuca, Bart De Pontieu, Lyndsay Fletcher, Sarah E. Gibson, Philip G. Judge, Yukio Katsukawa (+77 others)
2021 Solar Physics  
With this Critical Science Plan (CSP) we attempt to anticipate some of what those capabilities will enable, providing a snapshot of some of the scientific pursuits that the DKIST hopes to engage as start-of-operations  ...  Inouye Solar Telescope (DKIST) will revolutionize our ability to measure, understand, and model the basic physical processes that control the structure and dynamics of the Sun and its atmosphere.  ...  Acknowledgements This work rests on many years of sustained vision, effort, and dedication by DKIST  ... 
doi:10.1007/s11207-021-01789-2 fatcat:tza7wm3shnaibaicmkpf7raf4i
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