پیوندهای مفید
اخبار و اعلانات
آمار
| تعداد نشریات | 161 |
| تعداد شماره‌ها | 6,514 |
| تعداد مقالات | 70,372 |
| تعداد مشاهده مقاله | 123,848,902 |
| تعداد دریافت فایل اصل مقاله | 97,018,331 |
شناسایی نمایههای طیفی نامتقارن در ناحیه‌گذار خورشید | ||
| فیزیک زمین و فضا | ||
| مقاله 10، دوره 50، شماره 3، مهر 1403، صفحه 731-741 اصل مقاله (1.53 M) | ||
| نوع مقاله: مقاله پژوهشی | ||
| شناسه دیجیتال (DOI): 10.22059/jesphys.2024.368006.1007576 | ||
| نویسندگان | ||
| راضیه حسینی* ؛ حسین صفری | ||
| گروه فیزیک، دانشکده علوم، دانشگاه زنجان، زنجان، ایران. | ||
| چکیده | ||
| شناخت نقش فرایندهای مختلف برای درک گرمایش پلاسما تا میلیون‌ها درجه در ناحیه گذار و تاج خورشید بسیار مهم است. بر این اساس ما به بررسی نمایههای طیفی نامتقارن در ناحیه‌گذار خورشید می‌پردازیم. روش شناسایی این عدم‌تقارن‌ها بر اساس برازش الگوهای تک-دو گاوسی است. داده‌های طیفی مورد استفاده در این تحقیق توسط طیف‌نگار تصویربرداری ناحیه رابط (آیریس) در ۱۴ اکتبر ۲۰۱۵ در طول‌موج ۱۳۹۴ آنگستروم Si IV ثبت شده است. با بررسی بیش از ۱۰۳۰۰۰ طیف ناحیه‌گذار، با برآورد سه شرط تجربی، ۱۵۹۸ نمایه نامتقارن با عدم‌تقارن یک سمتی یا دوسمتی یافت شد. در این پژوهش سه شرط تجربی برآورد عدم‌تقارن در طیف معرفی می‌شود: (۱) مقدار معنا‌داری برازش الگوی تک‌گاوسی بیشتر از یک، (۲) حداقل شدت دو مؤلفه (قله اول و دوم در نمایه طیف) بیشتر از DN ۲۰ (تعداد فوتون‌های رسیده در قله نمایه طیف) و (۳) فاصله مراکز دو مؤلفه طیف در مقیاس سرعت بیشتر از ۲۰ کیلومتر بر ثانیه. بیشترین تعداد نمایههای نامتقارن مربوط به نمایه‌ای با یک مؤلفه در سمت آبی آن است. کمترین تعداد را نمایههایی ناسازگار با هر دو الگوی برازش تک و دو گاوسی (نمایههایی با دو بال) در اختیار دارند. ما نشان دادیم که موقعیت نمایههای نامتقارن روی نواحی با چگالی بالای شار مغناطیسی در اچ‌ام‌آی (ابزار مغناطیس نگار خورشیدی بر روی رصدخانه دینامیک خورشیدی اس دی‌او است) و همچنین نواحی شبه شبکه‌ای روشن در مقیاس بزرگ در تصویر رستر ۱۳۳۰ آنگستروم متمرکز است، که نشان‌دهنده ساز و کارهای مغناطیسی در بروز عدم‌تقارن طیف ناحیه گذار است. | ||
| کلیدواژه‌ها | ||
| خورشید؛ ناحیه‌گذار؛ نمایههای طیفی نامتقارن | ||
| عنوان مقاله [English] | ||
| Identification of the asymmetric spectral profiles in the solar transition region | ||
| نویسندگان [English] | ||
| Razieh Hosseini؛ Hossein Safari | ||
| Department of Physics, Faculty of Science, University of Zanjan, Zanjan, Iran. | ||
| چکیده [English] | ||
| The temperature of the solar atmosphere steeply increases in the transition region from the chromosphere to the corona. In the coronal temperatures, the coronal hole, quiet sun, and active regions are visible in the solar corona. The magnetic field controls the solar corona. Different physical processes (e.g. magnetic reconnection, waves) play a role in the coronal dynamics, which cause plasma heating to millions of degrees. Then, it is essential to understand the role of these processes. A more exact analysis of the emission line profiles to investigate the dynamics and thermal behavior of the coronal and transition region plasma is spectroscopy. The spectral line profiles are proof of the structural evolution of the magnetic field and plasma temperature in the coronal holes and quiet sun. So far, the study of coronal spectral lines indicates that most line profiles are well-fitted based on a single Gaussian profile. However, some spectral lines avoid from a single Gaussian model because they have least one excess component. Observations display that 5 % to 10 % of line profiles have the blueward asymmetry in the quiet sun and coronal holes. Considering the mentioned advantages of spectroscopy, we use the formed Si IV 1394 Å spectral line in the transition region from the Interface Region Imaging Spectrograph (IRIS) raster in a central-equatorial region of Sun on 14 October 2015. Also, we make co-spatiotemporal raster images from Atmospheric Imaging Assembly (AIA) 193 Å, IRIS/SJI 1330 Å and Helioseismic and Magnetic Imager (HMI) magnetograms. Our data includes quiet sun, coronal hole and bright points features. The Si IV 1394 Å spectral line profiles are fitted with the single and then with double Gaussian function. We apply three essential conditions to certify any spectral profiles as asymmetric profile by double Gaussian model, that is, (1) the asymmetric profile must have a goodness-of-fit greater ( ) than one for the single Gaussian fits, (2) the minimum intensity of the first and second component to be 20 DN and (3) the distance between the centers of the two components to be more significant than 20 km/s. 1598 asymmetric profiles that are found out of a total of 103,000 profiles. The four types of profiles are dominated as only blue wing, only red wing, two clear peaks and none of the three types (it has two wings). The most significant number of asymmetric profiles corresponds to a profile with a component on its blue side. The lowest number is possessed by profiles inconsistent with single and double Gaussian fitting models (two wings). The asymmetries are concentrated on positions with high magnetic flux density. Also, asymmetric profiles arise in the large-scale bright lane-like areas in the SJI 1330 Å raster map. Corresponding to these areas, the magnetic flux concentration in the HMI raster map shows most probably, the network lanes. This correspondence can indicate the magnetic source. The asymmetric profiles may be owing to the reconnection of the open magnetic field of coronal hole with the bright points’ loops for bright points inside and the boundary of coronal hole. Also, we may contemplate a similar plan for asymmetric profiles at the coronal hole boundary, where the open magnetic fields of coronal hole may be reconnected with the quiet sun's close loops. However, the asymmetry of profiles at quiet sun may be owing to the reconnection of closed loops at this region. It is clear that the blueward and redward asymmetry are signatures of downflow, and upflow that may be caused by magnetic reconnection. However, the bidirectional jets derived from magnetic reconnection at the forming height of Si IV 1394 Å may be a reason for the asymmetric profiles with two clear peaks and two wings. Magnetic reconnections below the formation height of Si IV 1394 Å in the transition region may be a reason for upflows. Also, the profiles with blue wing may be relevant to the upflow spread of jets. These profiles are mainly sited away from the jet footpoints and on the network jets. The reconnection events above the formation height of Si IV 1394 Å or coronal return flows may be a reason for downflows. The red wing of the spectral line profiles is probably relevant to the downflow arising from reconnections that mainly placed around the footpoints of grid jets. | ||
| کلیدواژه‌ها [English] | ||
| Sun, Transition Region, Asymmetric Spectral Profiles | ||
| مراجع | ||
|
Boerner, P., Edwards, C., Lemen, J., Rausch, A., Schrijver, C., Shine, R., & Shing, L. (2012). Initial calibration of the atmospheric imaging assembly (AIA) on the solar dynamics observatory (SDO). Solar Physics, 275. 41. Brooks, D. H., & Warren, H. P. (2009). Flows and motions in moss in the core of a flaring active region: evidence for steady heating. Astrophysical Journal , 703, L10. Chen, Y., Tian, H., Huang, Z., Peter, H., & Samanta, T. (2019). Investigating the transition region explosive events and their relationship to network jets. Astrophysical Journal, 873, 79. Cranmer, S. R. (2009). Coronal Holes. Solar Physics, 6, 3. Culhane, J. L., Korendyke, C. M., Watanabe, T., & Doschek, G. A. (2000). Extreme-ultraviolet imaging spectrometer designed for the Japanese Solar-B satellite. Instrumentation for UV/EUV Astronomy and Solar Missions, 4139, 294. De Pontieu, B., McIntosh Scott W., Hansteen Viggo H., & Schrijver Carolus J. (2009). Observing the roots of solar coronal heating in the chromosphere. Astrophysical Journal, 701, L1. De Pontieu, B., Title, A. M., Lemen, J. R., Kushner, G. D., Akin, D. J., Allard, B., Berger, T., & Boerner, P. (2014). The interface region imaging spectrograph (IRIS). Solar Physics, 289, 2733. Del Zanna, G. (2008). Flows in active region loops observed by Hinode EIS. Astronomy & Astrophysics, 481, L49. Garton, T. M., Gallagher, P. T., & Murray, S. A. (2018). Automated coronal hole identification via multi-thermal intensity segmentation. Journal of Space Weather and Space Climate, 8, A02. Hara, H., Watanabe, T., Harra, L. K., Culhane, J. L., Young, P. R., Mariska, J. T., & Doschek, G. A. (2008). Coronal plasma motions near footpoints of active region loops revealed from spectroscopic observations with Hinode EIS. Astrophysical Journal Letters, 678, L67. Harra, L., Sakao, T., Mandrini, C. H., Hara, H., Imada, S., Young, P. R., Driel-Gesztelyi, L., & Baker, D. (2008). Outflows at the edges of active regions: contribution to solar wind formation?. Astrophysical Journal Letters. 676, L147. Hassler, D. M., Rottman, G. J., Orrall, F. Q. (1991). Systematic radial flows in the chromosphere, transition region, and corona of the quiet Sun. Astrophysical Journal, 372, 710. Hosseini, R., Kayshap, P., Alipour, N., Safari, H., (2024), Asymmetry of the spectral lines of the coronal hole and quiet Sun in the transition region, Monthly Notices of the Royal Astronomical Society, doi: 10.1093/mnras/stae356. Insley, J. E., Moore, V., Harrison, R. A., (1995). The differential rotation of the corona as indicated by coronal holes. Solar Physics, 160, 1. Kayshap, P., Tripathi, D., Solanki, S. K., & Peter, H. (2018). Quiet-Sun and coronal hole in Mg II k line as observed by IRIS. Astrophysical Journal, 864, 21. Kjeldseth, Moe O., & Nicolas, K. R. (1977). Emission measures, electron densities, and nonthermal velocities from optically thin UV lines near a quiet solar limb. Astrophysical Journal, 211, 579. Klimchuk, J. A. (2006). On solving the coronal heating problem. Solar Physics, 234, 41. Ko, Y. K., Doschek, G. A., Warren, H. P., & Young, P. R. (2009). Hot plasma in nonflaring active regions observed by the extreme-ultraviolet imaging spectrometer on Hinode. Astrophysical Journal. 679, 1956. Krieger, A. S., Timothy, A. F., Roelof, E. C., (1973). A coronal hole and its identification as the source of a high velocity solar wind stream. Solar Physics, 29, 505. Lemen, J. R., Title, A. M., Akin, D. J., Boerner, P. F., Chou, C., Drake, J. F., & Duncan, D. W. (2012). The atmospheric imaging assembly (AIA) on the solar dynamics observatory (SDO). Solar Physics, 275, 17. Linker, J. A., Heinemann, S. G, Temmer, M., Owens, Mathew J, C., Ronald, M., & Arge, C. N. (2021). Coronal hole detection and open magnetic flux. Astrophysical Journal, 918, 21. Martínez-Sykora, J., De Pontieu, B., Hansteen, V., & McIntosh, S. W. (2011). What do spectral line profile asymmetries tell us about the solar atmosphere?. Astrophysical Journal, 732, 84. McIntosh, S. W., & De Pontieu, B. (2009a). Observing episodic coronal heating events rooted in chromospheric activity. Astrophysical Journal, 706, L80. McIntosh, S. W., & De Pontieu, B. (2009b). High-speed transition region and coronal upflows in the quiet Sun. Astrophysical Journal, 707, 542. Mishra, S. K., Sangal, K., Kayshap, P., Jelnek, P., Srivastava, A. K., & Rajaguru, S. P. (2023). Origin of quasi-periodic pulsation at the base of a Kink-unstable jet. Astrophysical Journal, 945, 113. Patsourakos, S., & Klimchuk, J. A. (2006). Nonthermal spectral line broadening and the nanoflare model. Astrophysical Journal, 647, 1452. Parker E. N. (1972). Topological dissipation and the small-scale fields in turbulent gases. Astrophysical Journal, 174, 499. Parnell, C. E., & De Moortel, I. (2012). A contemporary view of coronal heating. Philosophical Transactions of the Royal Society of London Series A, 370, 3217. Peter, H., & Judge, P. G. (1999). On the Doppler shifts of solar ultraviolet emission lines. Astrophysical Journal, 522, 1148. Peter, H., (2000). Multi-component structure of solar and stellar transition regions. Astronomy & Astrophysics, 360,761. Peter, H. (2001). On the nature of the transition region from the chromosphere to the corona of the Sun. Astronomy & Astrophysics, 374, 1108. Peter, H., Gudiksen, B. V., & Nordlund, A. (2006). Forward modeling of the corona of the Sun and solar-like stars: from a three-dimensional magnetohydrodynamic model to synthetic extreme-ultraviolet spectra. Astrophysical Journal, 638, 1086. Peter, H. (2010). Asymmetries of solar coronal extreme ultraviolet emission lines. Astronomy & Astrophysics, 521, A51. Sabri, S., Poedts, S., & Ebadi, H. (2019). Plasma heating by magnetoacoustic wave propagation in the vicinity of a 2.5D magnetic null-point. Astronomy & Astrophysics, 623, A81. Sabri, S., Ebadi, H., & Poedts, S. (2020). Plasmoids and Resulting Blobs due to the Interaction of Magnetoacoustic Waves with a 2.5D Magnetic Null Point. Astrophysical Journal, 902,11. Sabri, S., Ebadi, H., & Poedts, S. (2022). Propagation of the Alfven Wave and Induced Perturbations in the Vicinity of a 3D Proper Magnetic Null Point. Astrophysical Journal, 924, 126. Sabri, S., Poedts, S., Ebadi, H. (2023). How Nonlinearity Changes Different Parameters in the Solar Corona. Astrophysical Journal, 944, 72. Sakao, T., Kano, R., Narukage, N., Kotoku, J., Bando, T., DeLuca, E. E, & Lundquist, L. L. (2007). Continuous plasma outflows from the edge of a solar active region as a possible source of solar wind. Science, 318, 1585. Scherrer, P. H., Schou, J., Bush, R.I., Kosovichev, A.G., Bogart, R.S., Hoeksema, J. T., & Liu, Y. (2012). The helioseismic and magnetic imager (HMI) investigation for the solar dynamics observatory (SDO). Solar Physics, 275, 207. Stucki, K., Solanki, S. K., Pike, C. D., Schühle, U., Rüedi, I., Pauluhn, A., Brković, A. (2002). Properties of ultraviolet lines observed with the Coronal Diagnostic Spectrometer (CDS/SOHO) in coronal holes and the quiet Sun. Astronomy & Astrophysics, 381, 653. Upendran, V., & Tripathi, D. (2022). On the impulsive heating of quiet solar corona. Astrophysical Journal, 926, 138. Waldmeier, M. (1975). The coronal hole at the 7 march 1970 solar eclipse. Solar Physics, 40, 351. Wiegelmann, T., & Solanki, S. K. (2004). Why are coronal holes indistinguishable from the quiet Sun in transition region radiation?. SOHO 15 Coronal Heating, 575, 35. Wilhelm, K., Curdt, W., Marsch, E., Schuhle, U., Lemaire P., Gabriel, A., & Vial, J. C. (1995). SUMER - solar ultraviolet measurements of emitted radiation. Solar Physics, 162, 189. Wilhelm, K., (2000), Solar spicules and macrospicules observed by SUMER. Astronomy & Astrophysics, 360, 351.
| ||
|
آمار تعداد مشاهده مقاله: 375 تعداد دریافت فایل اصل مقاله: 311 |
||