pith. sign in

arxiv: 2604.05295 · v1 · submitted 2026-04-07 · 🌌 astro-ph.SR · physics.space-ph

Statistics of blob properties in two types of coronal streamers

Haiyi Li , Zhenghua Huang , Maria S. Madjarska , Youqian Qi , Hui Fu , Ming Xiong , Lidong Xia This is my paper

Pith reviewed 2026-05-10 20:01 UTC · model grok-4.3

classification 🌌 astro-ph.SR physics.space-ph
keywords streamer blobsactive region streamersquiet equatorial streamerssolar windblob velocityblob accelerationLASCO observationscoronal streamers
0
0 comments X

The pith

Blobs in active-region streamers occur twice as often with higher initial velocities than in quiet equatorial streamers.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper compares properties of propagating blobs in coronal streamers that have active regions at their base versus those that do not. Using a full year of SOHO/LASCO/C2 images from 2018, the authors measure occurrence rates, velocities, accelerations, and first-appearance heights for blobs in each category. They report that active-region streamers produce roughly twice as many blobs, which also start with significantly higher speeds and show a different pattern linking acceleration to appearance height. These statistical differences indicate that surface activity influences the dynamics of material higher in the corona and the structure of the solar wind.

Core claim

Our statistical analysis reveals that the occurrence rate of blobs in active region streamers (ARSs) is about twice as high as in quiet equatorial streamers (QESs). On average, ARS blobs have significantly higher initial velocities and slightly higher accelerations but slightly lower heights of first appearance. A weak positive correlation exists between initial velocities and heights of first appearance in both groups. The correlation between accelerations and heights is negative for ARS blobs and positive for QES blobs. These results provide statistical evidence that a higher degree of activity at the coronal base causes more dynamic blobs higher up and affects the structures of the solar风

What carries the argument

Statistical comparison of occurrence rate, initial velocity, acceleration, and first-appearance height between blobs identified in active region streamers and quiet equatorial streamers in LASCO/C2 images.

If this is right

  • Higher activity at the streamer base produces more frequent and faster-moving blobs at greater heights.
  • The opposite sign of the acceleration-height correlation in the two streamer types points to different propagation physics.
  • Blob statistics can serve as a tracer for how photospheric activity shapes the solar wind.
  • Solar wind originating above active-region streamers is expected to carry more variable structure than wind from quiet equatorial streamers.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • The factor-of-two difference in occurrence rate could be incorporated into models that link photospheric activity maps to predicted solar-wind variability.
  • Repeating the analysis over multiple solar cycles would test whether the reported contrasts remain stable when overall activity levels change.
  • Cross-checking blob trajectories with in-situ plasma measurements at L1 could confirm whether the observed velocity and acceleration differences reach Earth orbit.

Load-bearing premise

Observed differences in blob occurrence rate, velocity, and acceleration between the two streamer types are caused by the presence or absence of active regions at the base rather than by streamer geometry, line-of-sight effects, or selection biases.

What would settle it

A new set of observations in which streamers with and without active regions at the base, but matched for geometry and viewing angle, show no significant differences in blob occurrence rate or velocity distributions.

Figures

Figures reproduced from arXiv: 2604.05295 by Haiyi Li, Hui Fu, Lidong Xia, Maria S. Madjarska, Ming Xiong, Youqian Qi, Zhenghua Huang.

Figure 1
Figure 1. Figure 1: Example of the streamer classification. Panel A shows a composite image combining LASCO/C2 and AIA 171 Å images on 17 May 2018, from which the evolution in these obser￾vations allows us to determine whether there an active region exists at the streamer base. The streamer shown at the east limb (left side of the image) is an example of an ARS located above the active region of NOAA 12711 (as seen in the AIA… view at source ↗
Figure 2
Figure 2. Figure 2: LASCO/C2 and AIA 171 Å composite images of a QES (left panel) and an ARS (right panel). In the left panel, the QES is visible at the west limb, where no active region is visible at its base throughout its lifetime (see the AIA 171 Å observations). In the right panel, the ARS is visible at the east limb, with an active region (NOAA 12706) at its base. All times denoted in the figures refer to universal time… view at source ↗
Figure 3
Figure 3. Figure 3: Example showing how we obtained the parameters of a streamer blob. Panel (a) shows a running-difference image of LASCO/C2, where the dark blue line marks the propagating path of a streamer blob. Panel (b) is a time-distance diagram obtained along the dark blue line marked in panel (a) based on the running-difference images. The propagation of the blob is shown as the dark feature and the bright one above, … view at source ↗
Figure 4
Figure 4. Figure 4: Statistical results of the heights of first appearance of ARS (left panel) and QES blobs (right panel). The average and the standard de￾viation of the distributions are denoted a and s, respectively. the QESs, with standard deviations of 63.11 km s−1 in ARSs and 40.53 km s−1 in QESs. About 50% of the blobs in ARSs com￾pared with about 16% of blobs in QESs have initial velocities higher than 100 km s−1 , wh… view at source ↗
Figure 6
Figure 6. Figure 6: While the blobs propagate outward, most of them accel [PITH_FULL_IMAGE:figures/full_fig_p004_6.png] view at source ↗
Figure 5
Figure 5. Figure 5: Same as [PITH_FULL_IMAGE:figures/full_fig_p005_5.png] view at source ↗
Figure 6
Figure 6. Figure 6: Same as [PITH_FULL_IMAGE:figures/full_fig_p005_6.png] view at source ↗
Figure 7
Figure 7. Figure 7: Velocity as a function of height for 112 individual ARS blobs (left panel) and for 55 QES blobs (right panel). Each individual blob is traced by a solid circle of the same color. The cyan lines represent the solar wind speeds given by the Paker model (Parker 1958) [PITH_FULL_IMAGE:figures/full_fig_p006_7.png] view at source ↗
Figure 8
Figure 8. Figure 8: Scatter diagrams for initial velocities vs. heights of first appearance of the ARS blobs (left panel) and of the QES blobs (right panel). Each blue circle represents an individual blob. A black diamond shows the average value ob￾tained in a segment of 0.4 R⊙ (marked by the dashed red line), and the error bar in black de￾notes the 1σ error. The solid green line shows a linear fit to the segmented average va… view at source ↗
Figure 9
Figure 9. Figure 9: Same as [PITH_FULL_IMAGE:figures/full_fig_p006_9.png] view at source ↗
read the original abstract

Previous studies have shown that a streamer blob might originate in the lower corona and thus be affected by activity in that region. While the base of one streamer might differ from that of another, it can be cataloged into two distinct types: active region streamers (ARSs) that have active regions at their base, and quiet equatorial streamers (QESs) that do not have an active region underneath.The difference between the blob properties in ARSs and those in QESs remains unknown. By analyzing the whole-year observations from SOHO/LASCO/C2 in 2018, we carried out a statistical analysis of the properties of propagating blobs in ARSs and QESs. We found that the properties of streamer blobs are very different from one blob to another. The occurrence rate of blobs in ARSs is about twice as high as that in QESs. On average, the ARS blobs have significantly higher initial velocities and slightly higher accelerations, but slightly lower heights of first appearance than the QES blobs. There is a weak positive correlation between the initial velocities and heights of first appearance in the two groups of streamer blobs. The correlation between the accelerations and heights of first appearance in ARS blobs is negative, while that in QES blobs is positive. Our results provide statistical evidence that a higher degree of activity at the coronal base of a streamer can cause more dynamic blobs higher up, and that it affects the structures of the solar wind originating in the region.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

2 major / 2 minor

Summary. The paper performs a statistical comparison of propagating streamer blobs observed in SOHO/LASCO/C2 data throughout 2018, classifying streamers into active-region streamers (ARSs) and quiet equatorial streamers (QESs). It reports that ARS blobs occur at roughly twice the rate of QES blobs, exhibit higher average initial velocities and accelerations, appear at slightly lower heights, and show differing correlations between velocity/acceleration and first-appearance height. The authors conclude that greater base activity produces more dynamic blobs and influences solar-wind structure.

Significance. A well-controlled demonstration that base activity modulates blob kinematics would strengthen the link between low-corona conditions and the variability of the slow solar wind. The use of a full-year, uniform dataset is a positive feature, but the absence of methodological transparency and geometric controls limits the immediate impact.

major comments (2)
  1. [Methods and Results sections (abstract and main text)] The manuscript provides no description of the blob-detection algorithm, the criteria used to classify streamers as ARS versus QES, the total number of blobs and streamers in each category, or any statistical significance tests for the reported factor-of-two occurrence-rate difference and velocity/acceleration contrasts. These omissions are load-bearing for the central claim.
  2. [Discussion and Results] No quantitative matching, regression, or even summary statistics are given for streamer geometry (half-width, density scale height) or line-of-sight orientation derived from the LASCO images. Without such controls, the attribution of kinematic differences to base activity rather than systematic differences in streamer topology or detection bias cannot be evaluated.
minor comments (2)
  1. [Abstract] The abstract reports “slightly higher accelerations” and “slightly lower heights” without numerical values or uncertainties, making it impossible to judge the practical importance of these differences.
  2. [Results] The correlation statements (weak positive for velocity vs. height; opposite signs for acceleration vs. height) are presented without correlation coefficients, p-values, or scatter plots, reducing clarity.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for their constructive review and for recognizing the potential significance of linking base activity to blob kinematics in the slow solar wind. We agree that greater methodological detail and geometric controls are needed to support the central claims, and we will revise the manuscript accordingly.

read point-by-point responses

  1. Referee: [Methods and Results sections (abstract and main text)] The manuscript provides no description of the blob-detection algorithm, the criteria used to classify streamers as ARS versus QES, the total number of blobs and streamers in each category, or any statistical significance tests for the reported factor-of-two occurrence-rate difference and velocity/acceleration contrasts. These omissions are load-bearing for the central claim.

    Authors: We acknowledge that the original manuscript omitted these essential details. In the revised version we will add a dedicated Methods section that describes the blob-detection algorithm, the criteria for classifying streamers as ARS versus QES, the total numbers of blobs and streamers analyzed in each category, and the results of statistical significance tests (e.g., appropriate non-parametric tests) for the reported differences in occurrence rate, initial velocity, and acceleration. These additions will make the central claims transparent and reproducible. revision: yes

  2. Referee: [Discussion and Results] No quantitative matching, regression, or even summary statistics are given for streamer geometry (half-width, density scale height) or line-of-sight orientation derived from the LASCO images. Without such controls, the attribution of kinematic differences to base activity rather than systematic differences in streamer topology or detection bias cannot be evaluated.

    Authors: We agree that quantitative controls for streamer geometry and viewing geometry are important. In the revision we will include summary statistics for average streamer half-widths and density scale heights derived from the LASCO/C2 images for both the ARS and QES samples, together with a qualitative discussion of line-of-sight orientation. A full per-blob regression analysis lies outside the scope of the present statistical study, but the added averages will allow readers to assess whether topology differences could explain the observed kinematic contrasts. revision: partial

Circularity Check

0 steps flagged

No circularity: purely observational statistics from image data

full rationale

This paper performs a direct statistical analysis of streamer blobs using SOHO/LASCO/C2 observations in 2018. Streamers are classified into ARSs and QESs by the presence or absence of active regions at the base, and blob properties (occurrence rate, initial velocity, acceleration, height of first appearance, and correlations) are measured and compared empirically. No mathematical derivations, equations, parameter fitting, or model predictions are present; results are extracted counts and kinematics from the images without reduction to fitted inputs or self-referential steps. The central claim is an observational contrast, not a derived quantity.

Axiom & Free-Parameter Ledger

0 free parameters · 2 axioms · 0 invented entities

The study is purely observational and relies on standard solar-physics assumptions about image interpretation and streamer classification. No free parameters, new physical entities, or ad-hoc axioms are introduced in the abstract.

axioms (2)
  • domain assumption Propagating blobs can be reliably identified and tracked in LASCO/C2 white-light images
    The entire statistical analysis depends on consistent detection of moving features in coronagraph data.
  • domain assumption Streamers can be accurately classified as ARS or QES according to the presence of active regions at their base
    The two-type division is central to the comparison and is taken as given.

pith-pipeline@v0.9.0 · 5583 in / 1469 out tokens · 61961 ms · 2026-05-10T20:01:42.302301+00:00 · methodology

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Reference graph

Works this paper leans on

44 extracted references · 44 canonical work pages

  1. [1]

    2024, ApJ, 973, 130 Ambrož, P ., Druckmüller, M., Galal, A

    Alzate, N., Di Matteo, S., Morgan, H., Viall, N., & V ourlidas, A. 2024, ApJ, 973, 130 Ambrož, P ., Druckmüller, M., Galal, A. A., & Hamid, R. H. 2009 , Sol. Phys., 258, 243

    work page 2024

  2. [2]

    E., et al

    Antonucci, E., Downs, C., Capuano, G. E., et al. 2023, Physic s of Plasmas, 30, 022905

    work page 2023

  3. [3]

    T., et al

    Bemporad, A., Poletto, G., Suess, S. T., et al. 2003, ApJ, 593 , 1146

    work page 2003

  4. [4]

    2020, ApJ, 895, 123

    Boe, B., Habbal, S., & Druckmüller, M. 2020, ApJ, 895, 123

    work page 2020

  5. [5]

    E., Howard, R

    Brueckner, G. E., Howard, R. A., Koomen, M. J., et al. 1995, So l. Phys., 162, 357 Cécere, M., Wyper, P . F., Krause, G., Sahade, A., & Rice, O. E. K. 2025, A&A, 697, A155

    work page 1995

  6. [6]

    Q., et al

    Chen, Y ., Li, X., Song, H. Q., et al. 2009, ApJ, 691, 1936

    work page 2009

  7. [7]

    P ., Seaton, D

    Chitta, L. P ., Seaton, D. B., Downs, C., DeForest, C. E., & Hig ginson, A. K. 2023, Nature Astronomy, 7, 133

    work page 2023

  8. [8]

    Domingo, V ., Fleck, B., & Poland, A. I. 1995, Sol. Phys., 162, 1

    work page 1995

  9. [9]

    B., & Karpen, J

    Einaudi, G., Boncinelli, P ., Dahlburg, R. B., & Karpen, J. T. 1999, J. Geo- phys. Res., 104, 521

    work page 1999

  10. [10]

    1995, Space Sci

    Geiss, J., Gloeckler, G., & von Steiger, R. 1995, Space Sci. R ev., 72, 49

    work page 1995

  11. [11]

    T., Borrini, G., Asbridge, J

    Gosling, J. T., Borrini, G., Asbridge, J. R., et al. 1981, J. Geophys. Res., 86, 5438

    work page 1981

  12. [12]

    Higginson, A. K. & Lynch, B. J. 2018, ApJ, 859, 6

    work page 2018

  13. [13]

    T., Antiochos, S

    Karpen, J. T., Antiochos, S. K., Richard DeV ore, C., & Golub, L. 1998, ApJ, 495, 491

    work page 1998

  14. [14]

    & Livshits, M

    Koutchmy, S. & Livshits, M. 1992, Space Sci. Rev., 61, 393

    work page 1992

  15. [15]

    2021, ApJ, 920, L6

    Lee, J.-O., Cho, K.-S., An, J., et al. 2021, ApJ, 920, L6

    work page 2021

  16. [16]

    R., Title, A

    Lemen, J. R., Title, A. M., Akin, D. J., et al. 2012, Sol. Phys. , 275, 17

    work page 2012

  17. [17]

    2024, A&A, 683, A126

    Li, H., Huang, Z., Deng, K., et al. 2024, A&A, 683, A126

    work page 2024

  18. [18]

    2023, MNRAS, 518, 1776

    Liang, Y ., Qu, Z., Hao, L., Xu, Z., & Zhong, Y . 2023, MNRAS, 518, 1776

    work page 2023

  19. [19]

    Lynch, B. J. 2020, ApJ, 905, 139

    work page 2020

  20. [20]

    2023, A&A, 672, A100

    Lyu, S., Wang, Y ., Li, X., & Zhang, Q. 2023, A&A, 672, A100

    work page 2023

  21. [21]

    Lyu, S., Wang, Y ., & Owen, C. J. 2025, ApJ, 988, 152

    work page 2025

  22. [22]

    Parenti, S., Landi, E., & Bromage, B. J. I. 2003, Mem. Soc. Ast ron. Italiana, 74, 717

    work page 2003

  23. [23]

    Parker, E. N. 1958, ApJ, 128, 664 Pasachoff, J. M., Rušin, V ., Druckmüllerová, H., et al. 2011, ApJ, 734, 114 Pasachoff, J. M., Rušin, V ., Saniga, M., et al. 2015, ApJ, 800, 90

    work page 1958

  24. [24]

    D., Thompson, B

    Pesnell, W. D., Thompson, B. J., & Chamberlin, P . C. 2012, Sol . Phys., 275, 3

    work page 2012

  25. [25]

    C., Kohl, J

    Raymond, J. C., Kohl, J. L., Noci, G., et al. 1997, Sol. Phys., 175, 645

    work page 1997

  26. [26]

    C., Suleiman, R., Kohl, J

    Raymond, J. C., Suleiman, R., Kohl, J. L., & Noci, G. 1998, Spa ce Sci. Rev., 85, 283

    work page 1998

  27. [27]

    2014, Living Reviews in Solar Physics, 11, 4 Réville, V ., Fargette, N., Rouillard, A

    Reale, F. 2014, Living Reviews in Solar Physics, 11, 4 Réville, V ., Fargette, N., Rouillard, A. P ., et al. 2022, A&A, 659, A110

    work page 2014

  28. [28]

    & Tandberg-Hanssen, E

    Saito, K. & Tandberg-Hanssen, E. 1973, Sol. Phys., 31, 105

    work page 1973

  29. [29]

    Seaton, D. B. & Darnel, J. M. 2018, ApJ, 852, L9

    work page 2018

  30. [30]

    B., Hughes, J

    Seaton, D. B., Hughes, J. M., Tadikonda, S. K., et al. 2021, Na ture Astronomy, 5, 1029

    work page 2021

  31. [31]

    R., J., Lee, D

    Sheeley, N. R., J., Lee, D. D. H., Casto, K. P ., Wang, Y . M., & Rich, N. B. 2009, ApJ, 694, 1471

    work page 2009

  32. [32]

    Sheeley, N. R., J. & Rouillard, A. P . 2010, ApJ, 715, 300

    work page 2010

  33. [33]

    R., Wang, Y

    Sheeley, N. R., Wang, Y . M., Hawley, S. H., et al. 1997, ApJ, 48 4, 472

    work page 1997

  34. [34]

    Q., Chen, Y ., Liu, K., Feng, S

    Song, H. Q., Chen, Y ., Liu, K., Feng, S. W., & Xia, L. D. 2009, So l. Phys., 258, 129

    work page 2009

  35. [35]

    Q., Kong, X

    Song, H. Q., Kong, X. L., Chen, Y ., et al. 2012, Sol. Phys., 276 , 261

    work page 2012

  36. [36]

    2007, A&A, 475, 707

    Spadaro, D., Susino, R., V entura, R., V ourlidas, A., & Landi , E. 2007, A&A, 475, 707

    work page 2007

  37. [37]

    Suess, S. T. 1988, in Solar and Stellar Coronal Structure and Dynamics, ed. R. C. Altrock, 130–139

    work page 1988

  38. [38]

    K., Raymond, J

    Uzzo, M., Ko, Y . K., Raymond, J. C., Wurz, P ., & Ipavich, F. M. 2003, ApJ, 585, 1062 Vásquez, A. M., Nuevo, F. A., Burtovoi, A., et al. 2025, Sol. P hys., 300, 4 V asudevan, G., Shing, L., Mathur, D., et al. 2019, in Societyof Photo-Optical In- strumentation Engineers (SPIE) Conference Series, V ol. 11180, International Conference on Space Optics; ICSO ...

    work page 2003

  39. [39]

    Wang, Y . M. & Hess, P . 2018, ApJ, 859, 135

    work page 2018

  40. [40]

    Wang, Y . M. & Sheeley, N. R., J. 1992, ApJ, 392, 310

    work page 1992

  41. [41]

    M., Sheeley, N

    Wang, Y . M., Sheeley, N. R., J., & Rich, N. B. 2000, Geophys. Re s. Lett., 27, 149

    work page 2000

  42. [42]

    M., Sheeley, N

    Wang, Y . M., Sheeley, N. R., J., Walters, J. H., et al. 1998, Ap J, 498, L165

    work page 1998

  43. [43]

    & Mann, G

    Warmuth, A. & Mann, G. 2005, A&A, 435, 1123

    work page 2005

  44. [44]

    J., Seaton, D

    West, M. J., Seaton, D. B., Wexler, D. B., et al. 2023, Sol. Phy s., 298, 78 Article number, page 7

    work page 2023