PAS Scientifically Interesting Events logs (July 2022 - present)

Figure 1. Magnetic cloud-like structure followed by a stream interface .

Figure 2. An interplanetary shock captured with PAS 1s mode.

Figure 3. High-speed stream, shock, ICME on Jan 28 - Feb 8, 2025.

Figure 4. Earth-directed ICME, aurorae seen with Kp 4 – 8, clear magnetic cloud with cold protons and alphas and with heavier ions. High-speed hot wind after the magnetic cloud.

Figure 5. Interface between slow and fast streams on Dec 7th, and perhaps also on Dec 3rd and14th.

Figure 6. Interval with clear presence of alphas.

Figure 7. A familiar structure looking like either a stream interface or an ICME in the slow/intermediate-speed wind.

Figure 8. Stream interaction region with non-thermal protons and alpha particles especially in the fast wind. Significant data correction for the slow wind that preceded the stream interface.

Figure 9. Interplanetary shock with V jump of 60 km.s^-1 (Ratio Nd to Nu is about 2). Clear alpha particles. Non-thermal proton intervals.

Figure 10. Interesting interval with high-speed stream on October 27, 2024. Missed data context during WOL at the beginning of STP 332. Clear non-thermal ion intervals. Data quality is mostly good.

Figure 11. ICME in slow wind. Max proton speed ~ 420 km/s. Clear alpha particle flux. High correction factor due to low proton speed surrounding the structure.

Figure 12. PAS 1s mode except for Sep 23 – 25 in STP 328, where PAS was on 2s mode (see operation table). High correction factor (lower data quality) for slow wind streams. High solar activities with several ICMEs detected. PSP was also in the vicinity of SO during this perihelion.

Figure 13. An ICME-like structure. PAS 1s data. Good data quality throughout apart from the slow wind. Velocity jump > 400 km/s. Hot and dense ion stream (sheath) behind the velocity jump. The jump contains two-step-like shocks. Interesting non-thermal proton and alpha interval.

Figure 14. A shock at the perihelion (_{0.3 AU). PAS 1s data. Good data quality throughout apart from the slow wind. A shock with \Delta 𝑉} 400 km/s with a very dense interval behind the shock (sheath?).

Figure 15. Interesting structure at the perihelion (0.3 AU). PAS 1s data. Good data quality throughout apart from the slow wind. Either a stream interface (transition from slow- to high-speed stream) or an ICME with cold materials containing clear alpha particles. Featured by spiky structures (time scale of hours).

Figure 16. Slow, dense, and hot solar wind featured by spiky features (~ timescale of hours) in energy, velocity, temperature. A transition to intermediate/high-speed stream after Sep 30th.

Figure 17. Slow/intermediate fast wind intervals. Clear small-scale (hours) spiky features. Very dense SW interval after Sep 24.

Figure 18. Slow, dense, and hot solar wind featured by spiky features (~ timescale of hours) in energy, velocity, temperature. A transition to intermediate/high-speed stream after Sep 30th.

Figure 19. ICME with max H+ speed~ 700 km/s. Clear presence of non-thermal H+/He2+ populations (complex distribution functions).

Figure 20. Clear shock and sheath on Sep 4 followed by cold, tenuous H+ and He2+ streams on Sep 5. Another ICME with two-step shocks on Sep 6 followed by alternating cold and hot intervals. Data contamination by photoelectrons on September 4 - 6 visible as uniform energy flux across all energies in green.

Figure 21. Shock-ICME sampled with PAS 1s cadence.

Figure 22. Detected with PAS 1s data. Shock with V jump of 400 km/s. Clear sheath behind the shock. Proton speed in ICME ~ 1000 km/s. Secondary electron contamination on 23rd and 27th July.

Figure 23. Fast and hot stream (correlated velocity and temperature).

Figure 24. ICME detected at 0.94 AU with clear alpha particles and some additional ion species. Cold materials.

Figure 25. Two-step shocks on 13 - 14 June 2024.

Figure 26. An ICME preceded by a shock. Velocity jump > 200 km/s. Photoelectron contamination visible as uniform energy flux at all energies.

Figure 27. An ICME preceded by a shock. Velocity jump ~ 200 km/s. Plausibly clear flux rope structure. Clear alpha energy flux throughout.

Figure 28. An ICME at 0.45 AU with a shock and plausibly a flux rope with cold prominence materials. An additional species above He2+ omnidirectional energy flux.

Figure 29. Slow (V~ 350 km/s) and dense (200 /cc) wind with multiple populations and additional species.

Figure 30. Fast-/intermediate-speed wind on April 8th – 12th at 0.35 AU with a presence of jets throughout.

Figure 31. Dense wind interval preceding a high-speed stream. Presence of jets and sub-populations.

Figure 32. March – April 2024 Perihelion data (0.29 AU).

Figure 33. Slow and high-speed streams with broad energy flux. Presence of strong non-thermal H+ population.

Figure 34. Overview.

Figure 35. Zoom-in.

Figure 36. Note: the new PAS high cadence tests (1s or 2s) were running from Nov 2023 – 10 March 2024. There are several intervals with partial VDFs. PAS is on 2s cadence from March 11, 2024.

Figure 37. PAS was in 1s cadence, some partial VDF with 5 elevations. Nice wave activities upstream of the shocks seen by MAG.

Figure 38. IP shock or shock/ICME in moderate speed wind, calm upstream conditions.

Figure 39. Shock/ICME in slow wind with high alpha density in the trailing edge.

Figure 40. Dense ICME. Only partial VDF at the beginning of the interval.

Figure 41. Hot, slow streams at 0.3 AU. Some visible reflected ions upstream of the shock.

Figure 42. Mostly slow-intermediate speed wind with a few ICMEs. PAS static mode (window changes every 6h, 4s cadence). Distance 0.29 AU.

Figure 43. Possibly two ICMEs. 1st shock with \Delta V = 500 km/s, 2nd shock with \Delta V = 300 km/s. The ion energy flux of the 1st shock overshoots the PAS field of view. Alternate intervals of hot and cold materials.

Figure 44. A high density interval with clear He2+ (and possibly another ionized species above He2+?).

Figure 45. Alternating hot/cold intervals with clear He2+. There is possibly an IP shock on 20th of August at 4:00.

Figure 46. An IP shock, with some possible partial IP crossings.

Figure 47. An interval with the ion density enhancement.

Figure 48. An interplanetary (IP) shock in the slow wind.

Figure 49. An ICME on the 26th of July with maximum proton speed of 1130 km/s. There are two intervals of fast and dense protons. A cold trailing interval after the 2nd speed bump. There are some contaminations possibly due to photoelectrons across all the energies before the shock.

Figure 50. ICME with maximum proton speed of 800 km/s and intervals of cold H+ and He2+ (and some hot H+). A few hours interval with a very low density (0.02 cm-3).

Figure 51. ICME with maximum proton speed of 600 km/s and cold trailing interval (with a second proton peak, possibly a very fast beam, above the first peak).

Figure 52. A hot ion stream with intermediate/high speed wind, preceded by an intermediate/slow wind interval with clear He2+.

Figure 53. Slow, hot solar wind with some clear (dense) He2+.

Figure 54. Stream interaction region with clear H+ and He2+ in the trailing part (slow wind).

Figure 55. Cold stream of H+ and He2+ preceding hot stream (with a stream interface – like structure), followed by an ICME-like structure in intermediate – fast wind.

Figure 56. ICMEs in intermediate/slow wind with hot sheath and cold plasmas (0.5 AU).

Figure 57. A stream interface observed at 0.29 AU during the perihelion. The fast stream has a very high number density, reaching 1500 /cc. There is an intense He2+ energy flux with a clear separation from the cold protons in the fast stream.

Figure 58. An ICME with shock on the 20th and a cold/dense plasma with clear proton-alpha separation in the trailing part. This event was observed to have a strong Bz and it arrives at Earth.

Figure 59. A shock arrival.

Figure 60. A shock and/or stream interface with preceded cold plasma.

Figure 61. An interplanetary shock.

Figure 62. A potential Coronal Mass Ejection with a broaden shock region and a flux-rope structure at the trailing edge.

Figure 63. A drop of ion omnidirectional energy flux on the 24th December 2022, characterised by a 12-hr interval of a very low ion Eflux with n ~ 0.01 - 0.1 cm-3. Likely high uncertainties for moment calculations, seen as strong fluctuations of temperature and ion number density. SolO was located before Earth/MMS. Stereo-A was between SolO and Earth.

Figure 64. Slow and dense solar wind at 0.33 AU and high-speed streams plausibly containing switchback patches at 0.3 AU.

Figure 65. A shock/ICME arrival on the 6th of September 2022. High-speed protons up to 1100 km/s and high-temperature protons up to a few hundred eV in the shock. Cold protons in the magnetic cloud.

Figure 66. A stream interaction region / high-speed stream or an ICME arrival on the 3rd of September, 2022.

Figure 67. An ICME detected on the 1st of September 2022. Proton speed up to 1200 km/s in the shock. Cold plasma in the magnetic cloud. Data gap at the beginning STP 220, starting from 12:35 due to WOL and TCM.

Figure 68. Interplanetary shock. Warning - data quality factor exceeding the lower threshold before IP shock.

Figure 69. Shock/ICME arrival on 25/07/2022 with the proton bulk reaching ~1000 km/s.