Opening a Window on ICME-driven GCR Modulation in the Inner Solar System

Winslow, R. M.; Schwadron, N. A.; Lugaz, Noé; Guo, Jingnan; Joyce, Colin J.; Jordan, A. P.; Wilson, J. K.; Lawrence, D. J.; Wimmer‐Schweingruber, Robert F.; Mays, M. L.

doi:10.3847/1538-4357/aab098

Cited by 32 publications

(36 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, except for a few studies that used multipoint spacecraft observations (Burlaga et al, 1981;Cane et al, 1997;Farrugia et al, 2011;Good et al, 2015Good et al, , 2018Janvier et al, 2019;Kilpua et al, 2011;Möstl, 2015;Möstl et al, 2009;Prise et al, 2015;Wang et al, 2018;Winslow et al, 2016Winslow et al, , 2018, CME measurements are largely restricted to single-point observations in space (see also discussion in Lugaz et al, 2018). However, except for a few studies that used multipoint spacecraft observations (Burlaga et al, 1981;Cane et al, 1997;Farrugia et al, 2011;Good et al, 2015Good et al, , 2018Janvier et al, 2019;Kilpua et al, 2011;Möstl, 2015;Möstl et al, 2009;Prise et al, 2015;Wang et al, 2018;Winslow et al, 2016Winslow et al, , 2018, CME measurements are largely restricted to single-point observations in space (see also discussion in Lugaz et al, 2018).…”

Section: Introductionmentioning

confidence: 99%

“…With currently no plasma measurements at sub-1 AU heliocentric distances, we rely on models to simulate CME evolution in the inner heliosphere. In this study, we combine two distinct issues/types of research: multispacecraft measurements of the same CME with the spacecraft at the same radial distance (Burlaga et al, 1981;Kilpua et al, 2011;Möstl et al, 2009) and multispacecraft measurements of the same CME with the spacecraft at the same longitude (Farrugia et al, 2011;Good et al, 2015Good et al, , 2018Möstl, 2015;Prise et al, 2015;Wang et al, 2018;Winslow et al, 2016Winslow et al, , 2018. As a result, it is important to have multipoint observations to understand the governing physics behind CME propagation and evolution in the inner heliosphere.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Radial Evolution of Coronal Mass Ejections Between MESSENGER, Venus Express, STEREO, and L1: Catalog and Analysis

2020

View full text Add to dashboard Cite

Our knowledge of the properties of coronal mass ejections (CMEs) in the inner heliosphere is constrained by the relative lack of plasma observations between the Sun and 1 AU. In this work, we present a comprehensive catalog of 47 CMEs measured in situ measurements by two or more radially aligned spacecraft (MESSENGER, Venus Express, STEREO, Wind/ACE). We estimate the CME impact speeds at Mercury and Venus using a drag-based model and present an average propagation profile of CMEs (speed and deceleration/acceleration) in the inner heliosphere. We find that CME deceleration continues past Mercury's orbit but most of the deceleration occurs between the Sun and Mercury. We examine the exponential decrease of the maximum magnetic field strength in the CME with heliocentric distance using two approaches: a modified statistical method and analysis from individual conjunction events. Findings from both the approaches are on average consistent with previous studies but show significant event-to-event variability. We also find the expansion of the CME sheath to be well fit by a linear function. However, we observe the average sheath duration and its increase to be fairly independent of the initial CME speed, contradicting commonly held knowledge that slower CMEs drive larger sheaths. We also present an analysis of the 3 November 2011 CME observed in longitudinal conjunction between MESSENGER, Venus Express, and STEREO-B focusing on the expansion of the CME and its correlation with the exponential falloff of the maximum magnetic field strength in the ejecta.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Radial Evolution of Coronal Mass Ejections Between MESSENGER, Venus Express, STEREO, and L1: Catalog and Analysis

2020

View full text Add to dashboard Cite

show abstract

“…Past conjunctions between the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MES-SENGER; see Solomon et al, 2007) spacecraft at Mercury and spacecraft at 1 AU have made possible a number of detailed studies of CME evolution in the inner heliosphere (Winslow et al, 2016;Winslow et al, 2018;Good et al, 2015;Good et al, 2018;Wang et al, 2018;Vršnak et al, 2019). However, a number of physical questions regarding the evolution of CMEs have not been fully addressed by these past studies.…”

Section: Introductionmentioning

confidence: 99%

Evolution of a Long‐Duration Coronal Mass Ejection and Its Sheath Region Between Mercury and Earth on 9–14 July 2013

2020

View full text Add to dashboard Cite

Using in situ measurements and remote-sensing observations, we study a coronal mass ejection (CME) that left the Sun on 9 July 2013 and impacted both Mercury and Earth while the planets were in radial alignment (within 3 • ). The CME had an initial speed as measured by coronagraphs of 580 ± 20 km/s, an inferred speed at Mercury of 580 ± 30 km/s, and a measured maximum speed at Earth of 530 km/s, indicating that it did not decelerate substantially in the inner heliosphere. The magnetic field measurements made by MESSENGER and Wind reveal a very similar magnetic ejecta at both planets. We consider the CME expansion as measured by the ejecta duration and the decrease of the magnetic field strength between Mercury and Earth and the velocity profile measured in situ by Wind. The long-duration magnetic ejecta (20 and 42 hr at Mercury and Earth, respectively) is found to be associated with a relatively slowly expanding ejecta at 1 AU, revealing that the large size of the ejecta is due to the CME itself or its expansion in the corona or innermost heliosphere and not due to a rapid expansion between Mercury at 0.45 AU and Earth at 1 AU. We also find evidence that the CME sheath is composed of compressed material accumulated before the shock formed, as well as more recently shocked material.

show abstract

“…Over the last decade, the WSA relation for specifying solar wind conditions near the Sun has been one of the most frequently used modelling approaches for studying the consequences of evolving space weather in the heliosphere. Examples include the prediction of high-speed solar wind streams [33,21,39], the prediction of arrival time and speed of coronal mass ejections [59,69,49,63], the study of the sensitivity of CME events to model parameter settings [60,7], the propagation of coronal mass ejections in the evolving ambient solar wind [24,56], the prediction of solar energetic particles [23,19,66], the understanding of how the evolving ambient solar wind flow interacts with planetary magnetospheres [9], or the study of Forbush decreases in the flux of galactic cosmic rays [68].…”

Section: Introductionmentioning

confidence: 99%

Forecasting the Ambient Solar Wind with Numerical Models. II. An Adaptive Prediction System for Specifying Solar Wind Speed near the Sun

Reiss

MacNeice

Muglach

et al. 2020

ApJ

View full text Add to dashboard Cite

The ambient solar wind flows and fields influence the complex propagation dynamics of coronal mass ejections in the interplanetary medium and play an essential role in shaping Earth's space weather environment. A critical scientific goal in the space weather research and prediction community is to develop, implement and optimize numerical models for specifying the large-scale properties of solar wind conditions at the inner boundary of the heliospheric model domain. Here we present an adaptive prediction system that fuses information from in situ measurements of the solar wind into numerical models to better match the global solar wind model solutions near the Sun with prevailing physical conditions in the vicinity of Earth. In this way, we attempt to advance the predictive capabilities of well-established solar wind models for specifying solar wind speed, including the Wang-Sheeley-Arge (WSA) model. In particular, we use the Heliospheric Upwind eXtrapolation (HUX) model for mapping the solar wind solutions from the near-Sun environment to the vicinity of Earth. In addition, we present the newly developed Tunable HUX (THUX) model which solves the viscous form of the underlying Burgers equation. We perform a statistical analysis of the resulting solar wind predictions for the time 2006-2015. The proposed prediction scheme improves all the investigated coronal/heliospheric model combinations and produces better estimates of the solar wind state at Earth than our reference baseline model. We discuss why this is the case, and conclude that our findings have important implications for future practice in applied space weather research and prediction.

show abstract

Opening a Window on ICME-driven GCR Modulation in the Inner Solar System

Cited by 32 publications

References 39 publications

Radial Evolution of Coronal Mass Ejections Between MESSENGER, Venus Express, STEREO, and L1: Catalog and Analysis

Radial Evolution of Coronal Mass Ejections Between MESSENGER, Venus Express, STEREO, and L1: Catalog and Analysis

Evolution of a Long‐Duration Coronal Mass Ejection and Its Sheath Region Between Mercury and Earth on 9–14 July 2013

Forecasting the Ambient Solar Wind with Numerical Models. II. An Adaptive Prediction System for Specifying Solar Wind Speed near the Sun

Contact Info

Product

Resources

About