Variations of dose rate observed by MSL/RAD in transit to Mars

Guo, Jingnan; Zeitlin, C.; Wimmer‐Schweingruber, R. F.; Hassler, Donald M.; Posner, A.; Heber, B.; Köhler, Jan; Rafkin, Scot; Ehresmann, Bent; Appel, J. K.; Böhm, E.; Böttcher, S.; Burmeister, Sönke; Brinza, D. E.; Lohf, H.; Martı́n, César; Reitz, Günther

doi:10.1051/0004-6361/201525680

Cited by 44 publications

(32 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Mulligan et al 2009). Furthermore, a decrease in the abundance of energetic particles associated with FD has also been in situ observed by the Mars Science Laboratory's rover Curiosity, during its cruise phase from Earth to Mars (Guo et al 2015).…”

Section: Introductionmentioning

confidence: 77%

Superposed epoch study of ICME sub-structures near Earth and their effects on Galactic cosmic rays

Masías-Meza

Dasso

Démoulin

et al. 2016

A&A

113

View full text Add to dashboard Cite

Context. Interplanetary coronal mass ejections (ICMEs) are the interplanetary manifestations of solar eruptions. The overtaken solar wind forms a sheath of compressed plasma at the front of ICMEs. Magnetic clouds (MCs) are a subset of ICMEs with specific properties (e.g. the presence of a flux rope). When ICMEs pass near Earth, ground observations indicate that the flux of Galactic cosmic rays (GCRs) decreases. Aims. The main aims of this paper are to find common plasma and magnetic properties of different ICME sub-structures and which ICME properties affect the flux of GCRs near Earth. Methods. We used a superposed epoch method applied to a large set of ICMEs observed in situ by the spacecraft ACE, between 1998 and 2006. We also applied a superposed epoch analysis on GCRs time series observed with the McMurdo neutron monitors. Results. We find that slow MCs at 1 AU have on average more massive sheaths. We conclude that this is because they are more effectively slowed down by drag during their travel from the Sun. Slow MCs also have a more symmetric magnetic field and sheaths expanding similarly as their following MC, while in contrast, fast MCs have an asymmetric magnetic profile and a sheath in compression. In all types of MCs, we find that the proton density and the temperature and the magnetic fluctuations can diffuse within the front of the MC due to 3D reconnection. Finally, we derive a quantitative model that describes the decrease in cosmic rays as a function of the amount of magnetic fluctuations and field strength. Conclusions. The obtained typical profiles of sheath, MC and GCR properties corresponding to slow, middle, and fast ICMEs, can be used for forecasting or modelling these events, and to better understand the transport of energetic particles in ICMEs. They are also useful for improving future operative space weather activities.

show abstract

Section: Introductionmentioning

confidence: 77%

Superposed epoch study of ICME sub-structures near Earth and their effects on Galactic cosmic rays

Masías-Meza

Dasso

Démoulin

et al. 2016

A&A

113

View full text Add to dashboard Cite

show abstract

“…Without the Martian atmosphere around it, part of the RAD view cone was only very lightly shielded during this period (Zeitlin et al, ) and thus observed a different range of energies in the primary GCR spectrum and a higher number of SEP events. Besides, FDs were also detected during the cruise phase (Guo et al, ).…”

Section: Methodsmentioning

confidence: 99%

Tracking and Validating ICMEs Propagating Toward Mars Using STEREO Heliospheric Imagers Combined With Forbush Decreases Detected by MSL/RAD

et al. 2019

Self Cite

View full text Add to dashboard Cite

The Radiation Assessment Detector (RAD) instrument onboard the Mars Science Laboratory (MSL) mission's Curiosity rover has been measuring galactic cosmic rays (GCR) as well as solar energetic particles (SEP) on the surface of Mars for more than 6 years since its landing in August 2012. The observations include a large number of Forbush decreases (FD) caused by interplanetary coronal mass ejections (ICMEs) and/or their associated shocks shielding away part of the GCR particles with their turbulent and enhanced magnetic fields while passing Mars. This study combines MSL/RAD FD measurements and remote tracking of ICMEs using the Solar TErrestrial RElations Observatory (STEREO) Heliospheric Imager (HI) telescopes in a statistical study for the first time. The large data set collected by HI makes it possible to analyze 149 ICMEs propagating toward MSL both during its 8-month cruise phase and after its landing on Mars. We link 45 of the events observed at STEREO-HI to their corresponding FDs at MSL/RAD and study the accuracy of the ICME arrival time at Mars predicted from HI data using different methods. The mean differences between the predicted arrival times and those observed using FDs range from −11-5 hr for the different methods, with standard deviations between 17 and 20 hr. These values for predictions at Mars are very similar compared to other locations closer to the Sun and also comparable to the precision of some other modeling approaches. Citation:Freiherr von Forstner, J. L., Guo, J., Wimmer-Schweingruber, R. F., Temmer, M., Dumbović, M., Veronig, A., et al. (2019). Tracking and validating ICMEs propagating toward Mars using STEREO Heliospheric Imagers combined with Forbush decreases detected by MSL/RAD. Space Weather, 17, 586-598. https://doi.Mars, we will also directly compare these data at the two planets for better understanding their properties and interplanetary propagations. For up to about six events from this catalog, the ICME and FD properties can be better studied by also taking into account in situ measurements of solar wind and magnetic field from the MAVEN spacecraft that arrived at Mars in late 2014. However, MAVEN can only measure the upstream solar wind intermittently due to the spacecraft orbit (as discussed in section 1), resulting in frequent gaps in the data.Nevertheless, our current results are important for the understanding of space weather, but of course also for the development of future deep space missions and human spaceflight to Mars, where accurate predictions of ICMEs, their associated shocks and accompanying SEP events, and their impact are essential.

show abstract

“…MSL/RAD is an energetic particle detector and it has been carrying out radiation measurements of both particle types and fluxes together with dose and dose equivalent rates during its 11-month cruise phase (Zeitlin et al 2013;Posner et al 2013;Guo et al 2015a;Ehresmann et al 2016) and later on the surface of Mars since the landing of MSL in August 2012 Ehresmann et al 2014;Rafkin et al 2014;Köhler et al 2014;Wimmer-Schweingruber et al 2015;Guo et al 2015b). On the surface of Mars, RAD measures a mix of primary GCRs or SEPs and secondary particles generated in the atmosphere including both charged ) and neutral (Köhler et al 2014;Guo et al 2017b) particles.…”

Section: Gcr Measurement By Msl/radmentioning

confidence: 99%

Measurements of Forbush decreases at Mars: both by MSL on ground and by MAVEN in orbit

Guo

Lillis

Wimmer‐Schweingruber

et al. 2018

A&A

Self Cite

View full text Add to dashboard Cite

The Radiation Assessment Detector (RAD), on board Mars Science Laboratory's (MSL) Curiosity rover, has been measuring ground level particle fluxes along with the radiation dose rate at the surface of Mars since August 2012. Similar to neutron monitors at Earth, RAD sees many Forbush decreases (FDs) in the galactic cosmic ray (GCR) induced surface fluxes and dose rates. These FDs are associated with coronal mass ejections (CMEs) and/or stream/corotating interaction regions (SIRs/CIRs). Orbiting above the Martian atmosphere, the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft has also been monitoring space weather conditions at Mars since September 2014. The penetrating particle flux channels in the Solar Energetic Particle (SEP) instrument onboard MAVEN can also be employed to detect FDs. For the first time, we study the statistics and properties of a list of FDs observed in-situ at Mars, seen both on the surface by MSL/RAD and in orbit detected by the MAVEN/SEP instrument. Such a list of FDs can be used for studying interplanetary CME (ICME) propagation and SIR evolution through the inner heliosphere. The magnitudes of different FDs can be well-fitted by a power-law distribution. The systematic difference between the magnitudes of the FDs within and outside the Martian atmosphere may be mostly attributed to the energy-dependent modulation of the GCR particles by both the pass-by ICMEs/SIRs and the Martian atmosphere.

show abstract

Variations of dose rate observed by MSL/RAD in transit to Mars

Cited by 44 publications

References 22 publications

Superposed epoch study of ICME sub-structures near Earth and their effects on Galactic cosmic rays

Superposed epoch study of ICME sub-structures near Earth and their effects on Galactic cosmic rays

Tracking and Validating ICMEs Propagating Toward Mars Using STEREO Heliospheric Imagers Combined With Forbush Decreases Detected by MSL/RAD

Measurements of Forbush decreases at Mars: both by MSL on ground and by MAVEN in orbit

Contact Info

Product

Resources

About