16,739 research outputs found
Solar physics
Solar monitors on space platforms are discussed. Several experiments, utilizing different techniques for solar constants, spectral irradiance, and cross calibration carried out either on a space platform or a nearby satellite are included. The correlation monitors permit effective manned interface with the major solar instruments and with magnetospheric/atmospheric experiments requiring specific solar conditions before initiation
Solar physics in the space age
A concise and brief review is given of the solar physics' domain, and how its study has been affected by NASA Space programs which have enabled space based observations. The observations have greatly increased the knowledge of solar physics by proving some theories and challenging others. Many questions remain unanswered. To exploit coming opportunities like the Space Station, solar physics must continue its advances in instrument development, observational techniques, and basic theory. Even with the Advance Solar Observatory, other space based observation will still be required for the sure to be ensuing questions
Chameleon fields and solar physics
In this article we discuss some aspects of solar physics from the standpoint
of the so-called chameleon fields (i.e. quantum fields, typically scalar, where
the mass is an increasing function of the matter density of the environment).
Firstly, we analyze the effects of a chameleon-induced deviation from standard
gravity just below the surface of the Sun. In particular, we develop solar
models which take into account the presence of the chameleon and we show that
they are inconsistent with the helioseismic data. This inconsistency presents
itself not only with the typical chameleon set-up discussed in the literature
(where the mass scale of the potential is fine-tuned to the meV), but also if
we remove the fine-tuning on the scale of the potential. Secondly, we point out
that, in a model recently considered in the literature (we call this model
"Modified Fujii's Model"), a conceivable interpretation of the solar
oscillations is given by quantum vacuum fluctuations of a chameleon.Comment: 17 pages including figure
Report from solar physics
A discussion of the nature of solar physics is followed by a brief review of recent advances in the field. These advances include: the first direct experimental confirmation of the central role played by thermonuclear processes in stars; the discovery that the 5-minute oscillations of the Sun are a global seismic phenomenon that can be used as a probe of the structure and dynamical behavior of the solar interior; the discovery that the solar magnetic field is subdivided into individual flux tubes with field strength exceeding 1000 gauss. Also covered was a science strategy for pure solar physics. Brief discussions are given of solar-terrestrial physics, solar/stellar relationships, and suggested space missions
The Citation Impact of Digital Preprint Archives for Solar Physics Papers
Papers that are posted to a digital preprint archive are typically cited
twice as often as papers that are not posted. This has been demonstrated for
papers published in a wide variety of journals, and in many different subfields
of astronomy. Most astronomers now use the arXiv.org server (astro-ph) to
distribute preprints, but the solar physics community has an independent
archive hosted at Montana State University. For several samples of solar
physics papers published in 2003, I quantify the boost in citation rates for
preprints posted to each of these servers. I show that papers on the MSU
archive typically have citation rates 1.7 times higher than the average of
similar papers that are not posted as preprints, while those posted to astro-ph
get 2.6 times the average. A comparable boost is found for papers published in
conference proceedings, suggesting that the higher citation rates are not the
result of self-selection of above-average papers.Comment: 5 pages, 1 table, Solar Physics accepte
Solar Physics - Plasma Physics Workshop
A summary of the proceedings of a conference whose purpose was to explore plasma physics problems which arise in the study of solar physics is provided. Sessions were concerned with specific questions including the following: (1) whether the solar plasma is thermal or non-themal; (2) what spectroscopic data is required; (3) what types of magnetic field structures exist; (4) whether magnetohydrodynamic instabilities occur; (5) whether resistive or non-magnetohydrodynamic instabilities occur; (6) what mechanisms of particle acceleration have been proposed; and (7) what information is available concerning shock waves. Very few questions were answered categorically but, for each question, there was discussion concerning the observational evidence, theoretical analyses, and existing or potential laboratory and numerical experiments
Solar astronomy
An overview is given of modern solar physics. Topics covered include the solar interior, the solar surface, the solar atmosphere, the Large Earth-based Solar Telescope (LEST), the Orbiting Solar Laboratory, the High Energy Solar Physics mission, the Space Exploration Initiative, solar-terrestrial physics, and adaptive optics. Policy and related programmatic recommendations are given for university research and education, facilitating solar research, and integrated support for solar research
Solar Physics with the Square Kilometre Array
The Square Kilometre Array (SKA) will be the largest radio telescope ever
built, aiming to provide collecting area larger than 1 km. The SKA will
have two independent instruments, SKA-LOW comprising of dipoles organized as
aperture arrays in Australia and SKA-MID comprising of dishes in South Africa.
Currently the phase-1 of SKA, referred to as SKA1, is in its late design stage
and construction is expected to start in 2020. Both SKA1-LOW (frequency range
of 50-350 MHz) and SKA1-MID Bands 1, 2, and 5 (frequency ranges of 350-1050,
950-1760, and 4600-15300 MHz, respectively) are important for solar
observations. In this paper we present SKA's unique capabilities in terms of
spatial, spectral, and temporal resolution, as well as sensitivity and show
that they have the potential to provide major new insights in solar physics
topics of capital importance including (i) the structure and evolution of the
solar corona, (ii) coronal heating, (iii) solar flare dynamics including
particle acceleration and transport, (iv) the dynamics and structure of coronal
mass ejections, and (v) the solar aspects of space weather. Observations of the
Sun jointly with the new generation of ground-based and space-borne instruments
promise unprecedented discoveries.Comment: Accepted for publication in Advances in Space Researc
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