| Name: | Sruti Satyasmita |
| Affiliation: | Indian Institute of Technology, Hyderabad |
| Conference ID : | ASI2024_71 |
| Title : | Structures of kinetic scale magnetic discontinuity in solar wind turbulence |
| Authors : | Sruti Satyasmita1, Popi Das1, Kirit D. Makwana1 |
| Authors Affiliation: | 1 Sruti Satyasmita, Popi Das, Kirit D. Makwana Affiliation (Indian Institute of Technology, Telangana-
502285, India) |
| Mode of Presentation: | Poster |
| Abstract Category : | Sun, Solar System, Exoplanets, and Astrobiology |
| Abstract : | Solar wind is a turbulent medium with strong fluctuations ranging from the sidereal rotation period to kinetic scales. These fluctuations can be characterized by sudden changes in the magnetic field magnitude and/or direction. Such sudden changes can give rise to intermittency in the solar wind. Presence of intermittency can be corroborated if the increments found from time series spacecraft measurements deviate from a Gaussian distribution. Self-similarity is a characteristic feature of turbulence, so we also show that self-similarity is violated at small scales, giving another indication of presence of intermittency. Current sheets are one of the structures that can give rise to such intermittency. We apply three different methods to the fluxgate magnetometer data from the Magnetosphere Multiscale (MMS) mission to identify such events: time derivative of magnetic field using smoothing spline technique, Partial Variance of Increments (PVI), and modified Tsurutani-Smith (TS) method after the noise reduction. Using the three methods with varying noise reduction level, a consistent set of events are identified. The events identified using PVI and modified TS method match with that of spline method after adjusting the threshold for both the signals which operate at larger time increments in comparison to the spline method. The events are identified in all four MMS satellites and a simultaneity condition is applied so as to eliminate the spurious events as well as verify that these events are due to some physical phenomena, not just fluctuations. The magnetic field rotation angle across these events is also significantly larger than the average rotation angle calculated for such intervals. We also measured its time duration indicating that these structures are of the order or even smaller than ion kinetic scales. Further high resolution observations and numerical simulations are required to probe their real spatial-temporal scales. |
