LSC Adult Notables - Fall 2020 Published on Jun 12, 2020 Browse LSCs Fall 2020 adult best and solid selling titles, as chosen by a committee of librarians and LSC staff.In the nex t section we illustrate the results we obtaine d from observations made in 1998, at a latitude of 17 degr ees, as an example of the opportunities offer ed by quad rature data.We have used this technique to derive solar wind characteristics from the analysis of data acquired by SOHO and Ulysses when the SOHOSunUlysses included angle is 90 degrees: that is, when SOHO, the Sun and Ulysses are in quadrature.We summarize here the results obtained from the study of the December 1998 quadrature, when we focussed on the behavior of slow wind from lowlatitude regions, and anticipate some results from the June 2000 quadrature, which focussed on establishing a relationship between coronal and wind abundances of different elements and whose analysis is in progress.
We conclude by illustrating briefly the objectives of future quadrature studies. American Institute of Physics Cartoon showing past and future quadratures campaigns (arrows), as a function of the phase of the solar cycle. Top: wind speed for the June 20 to July 6, 2000, time interval, from the Ulysses SWOOPS experiment. Bottom: FeO ratio, over the same time span, from Ulysses SWICS experiment. The bars, which represent 1-day averages over SWICS data points, are drawn for the days when the coronal ratio has been evaluated from UVCS data. Figures - uploaded by Giannina Poletto Author content All figure content in this area was uploaded by Giannina Poletto Content may be subject to copyright. Ulysses 2.7.2 Free Public FullDiscover the worlds research 17 million members 135 million publications 700k research projects Join for free Public Full-text 1 Content uploaded by Giannina Poletto Author content All content in this area was uploaded by Giannina Poletto on Aug 02, 2014 Content may be subject to copyright. Poletto and S. T. Suess Osservatorio Astr osico di Ar cetri, Lar go E. F ermi 5, 5012 5 F ir enze, Italy NASA Marshall Space Flight Center, NSSTC, Huntsville, AL 35812 Abstract. Coronal and solar wind observ a tions of the same plasma, rst observed remotely in the corona and later, in situ, provide the best w ay to determine the evolution of plasma as it is being accelerated from the corona out to interplanetary distances. W e have used this technique to derive solar wind characteristics from the analysis of data acquired by SOHO and Ulysses when the SOHO-Sun-Ulysses included angle is 90 degrees: that is, when SOHO, the Sun and Ulysses are in quadrature. W e summarize here the results obtained from the study of the December 1998 quadrature, when we focussed on the behavior of slow wind from low-latitude re gions, and anticipate some results from the June 2000 quadrature, which focussed on establishing a relationship between coron al and wind abundances of dif ferent elements and whose analysis is in progress. W e conclud e by illustrating briey the objectiv es of future quadrature studies. INTR ODUCTION In the pre-SOHO era, the only possibility to observ e the same plasma rst remotely in the corona and, later, in situ, occurred when the Helios 1 and 2 pro bes were mov ing away from the Earth, and con v eniently located with respect to the P78 coronagraphs 1. W e ha ve made sev eral SOHO-Sun-Uly sses quad rature campaigns and plan to make mor e in future. ![]() Hence, the position of Ulysses dictates the scenario of the campaign, and, in part, its objectiv e: slo wfast wind analyses depen ding on wheth er Ulysses is at lowhigh latitudes. A quadrature campaign relies heavily on SOHO LASCO and UVCS coron al observ ations. LASCO pro- vides the ov erall coronal contex t above 2 solar radii and the UVCS spectrogr aph acqu ires data o v er a lim- ited range of altitudes, usually between 1.5 and 4.5 solar radii. The UVCS slit is set normal to the solar radius, with the radial to Ulysses crossing through its center. The grating positions, as well as the spatial and spectral resolution, are chosen to t the objective of the campaign. Coronal parameters are deri ved from data of these two exper iments and in situ parameters are pro- vided by Ulysses SWOOPS and SWICS experiments. Data from other sources, SUMER and CDS on SOHO or Sacramento Peak National Observato ry FeXIV maps and W ilcox Solar Observ atory magnetic eld maps, or the Ulysses magnetometer, have been occasionally used to complement the UVCSLASCO and SWOOPSSWICS data sets. At the time of this writing, we have led 8 quadra- ture campaigns, making observa tions at latitudes ranging from 10 to 80 degr ees, sampling both lo w and high lat- itude coronal plasma.
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