15 research outputs found
Sloan/Johnson-Cousins/2MASS Color Transformations for Cool-Stars
We present multi-color transformations and photometric parallaxes for a
sample of 40 low mass dwarfs selected from the Sloan Digital Sky Survey (SDSS)
and the General Catalog of Trigonometric Stellar Parallaxes. Our sample was
re-observed at the Manastash Ridge Observatory (MRO) using both Sloan and
Johnson-Cousin filters and color transformations between the two photometric
systems were derived. A subset of the sample had previously measured
Johnson-Cousins photometry and parallaxes as well as 2MASS photometry. We
observed these stars at MRO using Sloan filters and used these data to derive
photometric parallax relations as well as SDSS/Johnson-Cousins/2MASS color
transformations. We present the data and derived transformations for use in
future low mass star studies.Comment: 7 pages, Accepted for publication in PAS
Defining the Middle Corona
International audienceAbstract The middle corona, the region roughly spanning heliocentric distances from 1.5 to 6 solar radii, encompasses almost all of the influential physical transitions and processes that govern the behavior of coronal outflow into the heliosphere. The solar wind, eruptions, and flows pass through the region, and they are shaped by it. Importantly, the region also modulates inflow from above that can drive dynamic changes at lower heights in the inner corona. Consequently, the middle corona is essential for comprehensively connecting the corona to the heliosphere and for developing corresponding global models. Nonetheless, because it is challenging to observe, the region has been poorly studied by both major solar remote-sensing and in-situ missions and instruments, extending back to the Solar and Heliospheric Observatory (SOHO) era. Thanks to recent advances in instrumentation, observational processing techniques, and a realization of the importance of the region, interest in the middle corona has increased. Although the region cannot be intrinsically separated from other regions of the solar atmosphere, there has emerged a need to define the region in terms of its location and extension in the solar atmosphere, its composition, the physical transitions that it covers, and the underlying physics believed to shape the region. This article aims to define the middle corona, its physical characteristics, and give an overview of the processes that occur there
FORWARD MODELING TRANSIENT BRIGHTENINGS AND MICROFLARES AROUND AN ACTIVE REGION OBSERVED WITH Hi-C
MODELING ACTIVE REGION TRANSIENT BRIGHTENINGS OBSERVED WITH X-RAY TELESCOPE AS MULTI-STRANDED LOOPS
Defining the Middle Corona
The middle corona, the region roughly spanning heliocentric distances from 1.5 to 6 solar radii, encompasses almost all of the influential physical transitions and processes that govern the behavior of coronal outflow into the heliosphere. The solar wind, eruptions, and flows pass through the region, and they are shaped by it. Importantly, the region also modulates inflow from above that can drive dynamic changes at lower heights in the inner corona. Consequently, the middle corona is essential for comprehensively connecting the corona to the heliosphere and for developing corresponding global models. Nonetheless, because it is challenging to observe, the region has been poorly studied by both major solar remote-sensing and in-situ missions and instruments, extending back to the Solar and Heliospheric Observatory (SOHO) era. Thanks to recent advances in instrumentation, observational processing techniques, and a realization of the importance of the region, interest in the middle corona has increased. Although the region cannot be intrinsically separated from other regions of the solar atmosphere, there has emerged a need to define the region in terms of its location and extension in the solar atmosphere, its composition, the physical transitions that it covers, and the underlying physics believed to shape the region. This article aims to define the middle corona, its physical characteristics, and give an overview of the processes that occur there.ISSN:0038-0938ISSN:1573-093