Asset Details
Do you wish to reserve the book?
Solar Soft X-Ray Irradiance Variability, II: Temperature Variations of Coronal X-Ray Features
Hey, we have placed the reservation for you!
By the way, why not check out events that you can attend while you pick your title.
Oops! Something went wrong.
Looks like we were not able to place the reservation. Kindly try again later.
Are you sure you want to remove the book from the shelf?
Solar Soft X-Ray Irradiance Variability, II: Temperature Variations of Coronal X-Ray Features
Do you wish to request the book?
Solar Soft X-Ray Irradiance Variability, II: Temperature Variations of Coronal X-Ray Features
Please be aware that the book you have requested cannot be checked out. If you would like to checkout this book, you can reserve another copy
We have requested the book for you!
Your request is successful and it will be processed during the Library working hours. Please check the status of your request in My Requests.
Oops! Something went wrong.
Looks like we were not able to place your request. Kindly try again later.
Journal Article
Solar Soft X-Ray Irradiance Variability, II: Temperature Variations of Coronal X-Ray Features
2023
Overview
The temperature variations of the corona and its individual surface features as a function of the solar cycle are an interesting and important aspect of understanding the physics of the Sun. To study the temperature variations, we have used the full-disk soft X-ray images of the corona obtained from Hinode/X-Ray Telescope (XRT) in different filters. A sophisticated algorithm has been developed in Python to segment the different coronal features such as the active regions (ARs), coronal holes (CHs), background regions (BGs), and X-ray bright points (XBPs), derived the total intensity of all the features, and generated the temperature maps of the corona using the filter ratio method. Due to the XRT straylight issue in some filters and unavailability of a good pair of images, we used for our analysis the filter combinations of Ti-poly and Al-mesh for the period from February 01, 2008 to May 08, 2012 and Al-poly and Al-mesh for the period from May 09, 2012 to June 30, 2021, in total for 14 years which covers Solar Cycle 24. The first analysis in using the XRT intensity values of the coronal features from segmented solar disk and their relation to solar activity is presented. We discuss the temperature variations of a full-disk corona and all features (ARs, CHs, BGs, and XBPs). Our time series plots of the average temperature of the full-disk and all the features show temperature fluctuations synchronized with the solar cycle (sunspot number). Although the temperature of all features varies, but the mean temperature estimated for the whole observed period of the full-disk is around 1.29 ± 0.16 MK and active regions (ARs) are around 1.76 ± 0.32 MK, whereas BGs, CHs, and XBPs are 1.27 ± 0.15 MK, 1.23 ± 0.14 MK, and 1.37 ± 0.18 MK, respectively. In addition, we found that the mean temperature contribution estimated of the background regions (BGs) is around 93.2%, whereas ARs, CHs, and XBPs are 3.1%, 1.6% and 2.1%, respectively, to the average coronal temperature of the full-disk. The temperature values and their variations of all the features suggest that the features show a high variability in their temperature and that the heating rate of the emission features may be highly variable on solar cycle timescales. It is evident from the analysis that the filter-ratio method can be directly used for temperature analysis of coronal features and to study their surface temperature variability as a function of solar magnetic activity.
Publisher
Springer Netherlands,Springer Nature B.V,Springer Verlag
