Photospheric origins of chromospheric and coronal activity

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Published by National Aeronautics and Space Administration, National Technical Information Service, distributor in [Washington, DC, Springfield, Va .

Written in English

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Subjects:

  • Solar activity.

Edition Notes

Book details

Series[NASA contractor report] -- NASA-CR 195215., NASA contractor report -- NASA CR-195215.
ContributionsUnited States. National Aeronautics and Space Administration.
The Physical Object
FormatMicroform
Pagination1 v.
ID Numbers
Open LibraryOL14704510M

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Get this from a library. Photospheric origins of chromospheric and coronal activity. [United States. National Aeronautics and Space Administration.;]. Chromospheric and coronal activities in the quiet sun originating from photospheric 5-minute oscillations.

These stars are almost evenly split between stars showing hybrid-chromospheric and coronal outer atmospheric structures. EXOSAT observations have been obtained for three hybrid stars, of which only α TrA, the nearest, is detected.

The temperature of the emitting plasma is likely to be ∼10 by: 5. One of the great problems of astrophysics is the unanswered question about the origin and mechanism of chromospheric and coronal heating.

Just how these outer stellar envelopes are heated is of fundamental importance, since all stars have hot chromospheric and coronal shells where the temperature rises to millions of degrees, comparable to the temperatures in the stars' cores.

From the clear statistical relationship between the photospheric and coronal α values they inferred that the observed coronal twists, and their attendant currents, are of sub-photospheric origin.

This profile creates an isothermal photospheric-chromospheric layer at 0 Mm ≤ z photospheric density of ρ ph = × 10 −7 g cm Author: P. Syntelis, E. Priest. Abstract We present an extensive survey of the chromospheric and coronal activity among low-mass members of the Hyades open cluster.

We have obtained H alpha spectroscopy of 91 probable cluster members, including 23 that lie within three fields for which we have deep ROSAT X-ray observations.

20 of the 23 stars are detected in X-rays; the non-detections are probably not Hyades members. Recent observations at high spatial resolution have shown that magnetic flux cancellation occurs on the solar surface much more frequently than previously thought, and so this led Priest et al. () to propose magnetic reconnection driven by photospheric flux cancellation as a mechanism for chromospheric and coronal by: 7.; Wargelin et al.

The X-ray coronal and chromospheric activity have been studied in detail by Fuhrmeister et al. () and Wargelin et al. Re-cently Thompson et al. () claimed detection of rota-tional modulation of emission lines in the Proxima Cen spectrum.

Nowadays M dwarfs represent important targets for. Spicules are dynamic jets propelled upwards (at speeds of ∼20 km s-1) from the solar ‘surface’ (photosphere) into the magnetized low atmosphere of the Sun1,2,3. They carry a. Solar activity is associated with the appearance, temporal evolution and spatial modifications of the magnetic field at the solar surface and with its interactions with plasma mass flows.

Minor Photospheric and Chromospheric Magnetic Activity and Related Coronal Signatures | SpringerLinkAuthor: G. Cauzzi, A. Falchi, R. Falciani, E. Hiei, L. Smaldone. Thursday, - Magnetic Instabilities II 45 Physically consistent simulation of chromospheric and coronal magnetic fields Buchner, J¨ org¨ 1.

(1) Max-Planck-Institut fur Sonnensystemforschung¨ A popular approach in solar physics is the force-free extrapolation of photospheric magnetic fields to the corona. Comparison of Chromospheric and Coronal Chirality in Solar Filaments, and (Korea Astronomy and Space Science Institute) Introduction Chromospheric Chirality (Martin et al.

Solar phys,) Dextral If the filament channel goes to right from the positive polarity. Sinistral If the filament cannel goes to left. Inferences of the coronal magnetic field can be obtained by extrapolating measurements of the photospheric magnetic field vector (e.g., observed by Hinode/SOT, SOLIS, or the up-coming SDO/HMI instruments) into the corona.

Because the magnetic pressure dominates the plasma pressure in active-region coronae, making the plasma β low (see work by GaryCited by: Key for understanding solar activity: the solar magnetic field. How to measure the solar magnetic field. ● In-situ: magnetometer. ● Remote: magnetographs Method: Zeeman Effect: a magnetic field in a plasma produces: splitting of certain spectral lines (mostly photospheric and chromospheric) - polarisation of light.

Written by world-leading experts, these thirteen papers cover all regions of the subject from the solar interior, photosphere, chromosphere, active regions, and corona out to the solar wind.

The history of solar magnetic fields as well as the necessary instrumentation are also covered. photospheric spots and chromospheric activity M. Fernandez 1 and L.F. Miranda2 1 Max-Planck-Institut fur Astronomie, K¨onigst D Heidelberg, Germany ([email protected]) 2 Instituto de Astrof sica de Andaluc a, CSIC, Ap.

CorreosC/ Sancho Panza s/n, E Granada, Spain ([email protected]). The IRIS instrument [De Pontieu et al., ] observes the chromospheric lines of MgII h and k in the UV, as well as photospheric and coronal lines at subarcsecond spatial resolution with 2 s temporal resolution over a field of view of × arc sec.

The IRIS provides a wealth of information but does not include polarimetry and cannot Cited by: Flares and Eruptive Activity. These precursors have long been observed to appear minutes to an hour before the main flare in chromospheric and coronal images as small-scale multiple brightenings and/or plasma flows.

dense material of chromospheric / photospheric origin is sometimes involved. The CME plasma is entrained on an expanding. CORONAL MASS EJECTIONS: OVERVIEW OF OBSERVATIONS H. HUDSON1, J.-L. BOUGERET2 and J. BURKEPILE3 1Space Sciences Laboratory, University of California, Berkeley, CA USA 2Observatoire de Paris, Meudon, France 3High Altitude Observatory, Boulder, CO, USA Received: 11 October ; Accepted in final form: 7 March Abstract.

We survey the subject of Coronal. The solar magnetic field controls the dynamics and topology of all coronal phenomena. Heated plasma flows along magnetic field lines and energetic particles can only propagate along magnetic field lines.

Coronal loops are nothing other than conduits filled with heated plasma, shaped by the geometry of the coronal magnetic field, where cross-field diffusion is strongly inhibited.

Define chromospheric. chromospheric synonyms, chromospheric pronunciation, chromospheric translation, English dictionary definition of chromospheric. flux tubes in nonmagnetic environment [62], in magnetic tubes of partially ionized plasma [63], in spicules [], in photospheric tubes [67], in high-temperature and waves, reconnection.

The chromosphere (literally, "sphere of color") is the second of the three main layers in the Sun's atmosphere and is roughly 3, to 5, kilometers deep.

The chromosphere's rosy red color is only apparent during eclipses. The chromosphere sits just above the photosphere and below the solar transition region. The Physics of Chromospheric Plasmas - Proceedings of the Coimbra Solar Physics Meeting Held at the University of Coimbra, - A Short History of the New World Order, Ronald Wright Garfield Halloween Coloring & Activity Book Empirical Clinical Practice, Srinika.

It is now widely recognized that the chromosphere and corona have a common origin in the mechanical energy flux generated in the hydrogen convection zone lying beneath the photosphere. Furthermore, magnetic field phenomena appear to be as vital to Pages: Search the history of over billion web pages on the Internet.

Featured texts All Books All Texts latest This Just In Smithsonian Libraries FEDLINK (US) Genealogy Lincoln Collection. Books to Borrow. Top Chromospheric and photospheric evolution of an extremely active solar region in solar cycle 19".

Preface Theplans forthe Heidelberg ConferenceMechanisms of Chromospheric and Coro- nal Heating, held from June 5 to 8, ,materialized during several discussions between Eric Priest, Robert Rosner, Peter Ulmschneider, and later Jeff Linsky at meetings in.

Abstract: We explore the biological damage initiated in the environments of F, G, K, and M-type main-sequence stars due to photospheric, chromospheric and flare radiation. The amount of chromospheric radiation is, in a statistical sense, directly coupled to the stellar age as well as the presence of significant stellar magnetic fields and dynamo activity.

The rise and decay rates of episodes of major activity progress from those for the hot coronal EUV lines and the ‐cm flux to slower values for the chromospheric H Lyman alpha line, 10,‐Å line, and photospheric ‐Å UV by: A Coronal Mass Ejection (CME; see Figure 1) is “ an observable change in coronal structure that 1) occurs on a time scale of a few minutes and several hours and 2) involves the appearance and outward motion of a new, discrete, bright, white-light feature in the coronagraph field of view” (Hundhausen et al., ; Schwenn, ).

With a File Size: 1MB. Due to the heightened magnetic activity in these coronal loop regions, coronal loops can often be the precursor to solar flares and coronal mass ejections (CMEs). The Solar plasma that feed these structures is heated from under 6 K to well over 10 6 K from the.

In this review, our present day understanding of the Sun's global photospheric and coronal magnetic fields is discussed from both observational and theoretical viewpoints. Firstly, the large-scale properties of photospheric magnetic fields are described, along with recent advances in photospheric magnetic flux transport models.

Following this, the wide variety of theoretical models used to. The energy of solar flares comes from the magnetic field in the solar atmosphere [ 1 ]. Major flares usually originate from solar active regions (ARs).

In solar ARs, strong and concentrated bipolar magnetic field exists and manifests as dark sunspots in photosphere [ 2, 5 ].Author: Han He. Numerical 3-D Simulations of the Collapse of Photospheric Flux Tubes.- Chromospheric and Coronal Indicators of Stellar Magnetic Structure.- II.

Rotation - Activity - Cycle - Age Connection: Observations.- The Observed Relationships between Some Solar Rotation Parameters and the Activity Cycle.- The Mount Wilson Program for Stellar Activity Cycles Basic Plasma Processes on the Sun by E.

Priest,available at Book Depository with free delivery worldwide. The activity of the Sun is known to undergo cyclic variations with an 11 year period (22 year period for magnetic activity), as manifest in several activity indicators, including the number and surface area of sunspots, total solar irradiance, chromospheric and coronal activity, and magnetic morphology (e.g.

[,]).Cited by: Buy Solar Magnetic Fields: From Measurements Towards Understanding (Space Sciences Series of ISSI) on FREE SHIPPING on qualified orders. Chromospheric and coronal fields Solar chromospheric magnetic fields [C.

Keller (USA)] Lunch Solar coronal magnetic fields [S.M. White (USA)] Magnetic field diagnostic techniques Magnetic field diagnostic techniques through the Zeeman and Hanle effect.

A corona (Latin, 'crown') is an aura of plasma that surrounds the sun and other celestial bodies. The Sun's corona extends millions of kilometres into space and is most easily seen during a total solar eclipse, but it is also observable with a coronagraph.

The word "corona" is a Latin word meaning "crown", from the Ancient Greek κορώνη (korōnè, “garland, wreath”).

The high. The lowest layer of the sun's atmosphere is the photosphere. It is about miles ( kilometers) thick. This layer is where the sun's energy is released as light. Because of the distance from.

@article{osti_, title = {Image-optimized Coronal Magnetic Field Models}, author = {Jones, Shaela I. and Uritsky, Vadim and Davila, Joseph M., E-mail: [email protected], E-mail: [email protected]}, abstractNote = {We have reported previously on a new method we are developing for using image-based information to improve global coronal magnetic field models.It is also known that lots of dynamic phenomena, such as chromospheric jets and Ellerman bombs, make high-speed flows and heating in the chromosphere through the emerging process involving magnetic reconnection.

Major activities, such as flares and CMEs, are sometimes triggered by field emergence in an active region.Photospheric magnetic field not only plays important roles in building up free energy and triggering solar eruptions, but also has been observed to change.

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