Horizon 2020 Framework Programme
http://hdl.handle.net/10017/49348
Horizon 2020 Framework Programme2024-03-28T09:04:03ZUnusually long path length for a nearly scatter-free solar particle event observed by Solar Orbiter at 0.43 au
http://hdl.handle.net/10017/60961
Unusually long path length for a nearly scatter-free solar particle event observed by Solar Orbiter at 0.43 au
Wimmer-Schweingruber, R. F.; Berger, L.; Kollhoff, A.; Kühl, P; Heber, B.; Yang, Liu; Heidrich-Meisner, V; Klassen, A; Gómez Herrero, Raúl; Rodríguez-Pacheco Martín, Javier; Ho, George; Mason, Glenn M.; Janitzek, N. P; Kouloumvakos, A.; Wang, Linghua; Warmuth, A.; Lario, David; Carcaboso Morales, Fernando; Owen , C. J.; Bučík, Radoslav; Pacheco, D.; Malandraki, O. E.; Allen, R.C.; Rodríguez, Luciano; Shukhobodskaia, Daria; Espinosa Lara, Francisco; Cernuda Cangas, Ignacio Manuel; Böttcher, S.; Eldrum, S.; Fleth, S.; Xu, Zigong
Context. After their acceleration and release at the Sun, solar energetic particles (SEPs) are injected into the interplanetary medium and are bound to the interplanetary magnetic field (IMF) by the Lorentz force. The expansion of the IMF close to the Sun focuses the particle pitch-angle distribution, and scattering counteracts this focusing. Solar Orbiter observed an unusual solar particle event on 9 April 2022 when it was at 0.43 astronomical units (au) from the Sun.
Aims. We show that the inferred IMF along which the SEPs traveled was about three times longer than the nominal length of the Parker spiral and provide an explanation for this apparently long path.
Methods. We used velocity dispersion analysis (VDA) information to infer the spiral length along which the electrons and ions traveled and infer their solar release times and arrival direction.
Results. The path length inferred from VDA is approximately three times longer than the nominal Parker spiral. Nevertheless, the pitch-angle distribution of the particles of this event is highly anisotropic, and the electrons and ions appear to be streaming along the same IMF structures. The angular width of the streaming population is estimated to be approximately 30 degrees. The highly anisotropic ion beam was observed for more than 12 h. This may be due to the low level of fluctuations in the IMF, which in turn is very probably due to this event being inside an interplanetary coronal mass ejection The slow and small rotation in the IMF suggests a flux-rope structure. Small flux dropouts are associated with very small changes in pitch angle, which may be explained by different flux tubes connecting to different locations in the flare region.
Conclusions. The unusually long path length along which the electrons and ions have propagated virtually scatter-free together with the short-term flux dropouts offer excellent opportunities to study the transport of SEPs within interplanetary structures. The 9 April 2022 solar particle event offers an especially rich number of unique observations that can be used to limit SEP transport models.
2023-10-10T00:00:00ZVirtual assessment of a possible meningioma in a Roman-period cranium
http://hdl.handle.net/10017/60903
Virtual assessment of a possible meningioma in a Roman-period cranium; Estudio virtual de un probable meningioma en un cráneo de época romana
Rodríguez Iglesias, Daniel; Pantoja Pérez, Ana; Fernández Colón, Pilar; Pablos, Adrián; Alcaraz Castaño, Manuel; Sala, Nohemi
Diseases have accompanied human populations since prehistoric times. Knowing the paleopathologies and their consequences derived from them can help us to understand their impact and how have been decisive in our ancestors' ways of life. Taphonomic and paleopathological studies are key to understanding how injuries occurred; they can provide information on causes of death, analyzed populations behaviour, such as the existence of interpersonal conflicts or how they took the care of the sick. Those studies also confirm the existence of certain diseases, mentioned in the archaeological record. This paper explains the analysis of four lesions found in a Roman-era cranium from Sima de Marcenejas, located in Northern Spain. An anthropological analysis of this cranium has revealed that it corresponds to an adult male individual. This work focuses on the differential diagnosis of the lesions, to be able to discern the most likely aetiologies. The following techniques have been implemented: classical morphological analysis, forensic taphonomic analysis and virtual analysis. MicroCT and 3D microscopy have been used as essential tools for the virtual analysis of the cranium and its lesions. The results obtained revealed the existence of a tumour and three exocranial traumas, all of them antemortem. The location of the tumour, as well as its morphology together with other aspects, support the meningioma as the most probable tumour type. This possible ancient meningioma represents the first case for these chronologies on the Iberian Peninsula, where there are few documented cases. The three traumatic lesions reveal the existence of injuries produced by both, blunt and sharp objects, related to events of interpersonal violence. By applying virtual 3D analyses, the researchers have demonstrated that it is viable to identify tumours in those internal cranial regions, where the lesion is not visible, thus providing new comparative data for the paleopathological record of past populations.; Las enfermedades han acompañado a las poblaciones humanas desde la prehistoria. Conocer las paleopatologías y sus
consecuencias puede ayudar a entender cómo han influido en las formas de vida de las poblaciones del pasado. Los
estudios tafonómicos y paleopatológicos son claves para entender el origen de las lesiones; también pueden aportar
información sobre las causas de muerte, el comportamiento de las poblaciones analizadas, así como la existencia de
conflictos interpersonales o el cuidado de los enfermos. De esta manera se pueden obtener datos sobre la existencia de
determinadas enfermedades en el registro arqueológico. Aquí presentamos el análisis de cuatro lesiones encontradas
en un cráneo romano de la cueva de Marcenejas, situada en el norte de España. El análisis antropológico de este
VIRTUAL ASSESSMENT OF A POSSIBLE MENINGIOMA IN A ROMAN-PERIOD CRANIUM
Virtual Archaeology Review, 14(29): 14-25, 2023 15
cráneo ha revelado que corresponde a un individuo masculino adulto. Este trabajo se centra en el diagnóstico diferencial
de las lesiones para discernir las etiologías más probables. Se han aplicado las siguientes técnicas: análisis morfológico
clásico, análisis tafonómico forense y análisis virtual. La microtomografía computarizada (MicroTC) y la microscopía 3D
se han empleado como herramientas esenciales para el análisis virtual del cráneo y sus lesiones. Los resultados
obtenidos han revelado la existencia de un tumor y tres traumatismos exocraneales, todos ellos ante mortem. La
localización del tumor, así como su morfología junto con otros aspectos apoyan el meningioma como tipo de tumor más
probable. Este meningioma representa el primer caso para estas cronologías en la Península Ibérica, donde hay pocos
casos documentados. Las tres lesiones traumáticas revelan la existencia de lesiones producidas tanto por objetos
contundentes como cortantes, relacionadas con eventos de violencia interpersonal. La aplicación del análisis 3D virtual
ha demostrado que es factible identificar tumores en aquellas regiones craneales internas donde la lesión no es visible,
aportando nuevos datos comparativos para el registro paleopatológico de poblaciones del pasado.
2023-07-28T00:00:00ZThe 17 April 2021 widespread solar energetic particle event
http://hdl.handle.net/10017/60658
The 17 April 2021 widespread solar energetic particle event
Dresing, N.; Rodríguez García, Laura; Jebaraj, I.C.; Warmuth, A.; Wallace, S.; Balmaceda, Laura; Podladchikova, T.; Strauss, R. D.; Kouloumvakos, A.; Palmroos, Christian; Krupar, V.; Gieseler, Jan; Xu, Z. G.; Mitchell, J. G.; Cohen, C. M. S.; De Nolfo, G. A.; Palmerio, Erika; Carcaboso Morales, Fernando; Kilpua, E. J.; Trotta, Domenico; Auster, U.; Asvestari, E.; Da Silva, D.; Droege, W.; Getachew, T.; Gómez Herrero, Raúl; Grande, M.; Heyner, D.; Holmstroem, M.; Huovelin, J.; Kartavykh, Y.; Laurenza, M.; Lee, C. O.; Mason, G. M.; Maksimovic, M.; Mieth, J.; Murakami, G.; Oleynik, P.; Pinto, M.; Pulupa, M.; Richter, I.; Rodríguez-Pacheco Martín, Javier; Sánchez Cano, B.; Schuller, F.; Ueno, H.; Vainio, R.; Vecchio, A.; Veronig, Astrid; Wijsen, N
Context. A complex and long-lasting solar eruption on 17 April 2021 produced a widespread solar energetic particle (SEP) event that was observed by five longitudinally well-separated observers in the inner heliosphere that covered distances to the Sun from 0.42 to 1 au: BepiColombo, Parker Solar Probe, Solar Orbiter, STEREO A, and near-Earth spacecraft. The event was the second widespread SEP event detected in solar cycle 25, and it produced relativistic electrons and protons. It was associated with a long-lasting solar hard X-ray flare that showed multiple hard X-ray peaks over a duration of one hour. The event was further accompanied by a medium-fast coronal mass ejection (CME) with a speed of 880 km s�1 that drove a shock, an extreme ultraviolet wave, and long-lasting and complex radio burst activity that showed four distinct type III burst groups over a period of 40 min. Aims. We aim to understand the reason for the wide spread of elevated SEP intensities in the inner heliosphere as well as identify the underlying source regions of the observed energetic electrons and protons. Methods.We applied a comprehensive multi-spacecraft analysis of remote-sensing observations and in situ measurements of the energetic particles and interplanetary context to attribute the SEP observations at the di erent locations to the various potential source regions at the Sun. We used an ENLIL simulation to characterize the complex interplanetary state and its role in the energetic particle transport. The magnetic connection between each spacecraft and the Sun was determined using ballistic backmapping in combination with potential field source surface extrapolations in the lower corona. Using also a reconstruction of the coronal shock front, we then determined the times when the shock establishes magnetic connections with the di erent observers. Radio observations were used to characterize the directivity of the four main injection episodes, which were then employed in a 2D SEP transport simulation to test the importance of these di erent injection episodes. Results. A comprehensive timing analysis of the inferred solar injection times of the SEPs observed at each spacecraft suggests di erent source processes being important for the electron and proton events. Comparison among the characteristics and timing of the potential particle sources, such as the CME-driven shock or the flare, suggests a stronger shock contribution for the proton event and a more likely flare-related source for the electron event. Conclusions. In contrast to earlier studies on widespread SEP events, we find that in this event an important ingredient for the wide SEP spread was the wide longitudinal range of about 110 covered by distinct SEP injections, which is also supported by our SEP transport modeling.
2023-06-01T00:00:00ZInfluence of large-scale interplanetary structures on the propagation of solar energetic particles: the multispacecraft event on 2021 October 9
http://hdl.handle.net/10017/60657
Influence of large-scale interplanetary structures on the propagation of solar energetic particles: the multispacecraft event on 2021 October 9
Lario, D.; Wijsen, N; Kwon, R.Y.; Sánchez Cano, B.; Richardson, I. G.; Pacheco, D.; Palmeiro, E.; Stevens, M.L.; Szabo, A.; Heyner, D.; Dresing, N.; Gómez Herrero, Raúl; Carcaboso Morales, Fernando; Aran, A.; Afanasiev, A.; Vainio, R.; Riihonen, E.; Poedts, S.; Brudern, M.; Kollhoff, A.
An intense solar energetic particle (SEP) event was observed on 2021 October 9 by multiple spacecraft distributed near the ecliptic plane at heliocentric radial distances R ? 1 au and within a narrow range of heliolongitudes. A stream interaction region (SIR), sequentially observed by Parker Solar Probe (PSP) at R = 0.76 au and 48° east from Earth (? = E48°), STEREO-A (at R = 0.96 au, ? = E39°), Solar Orbiter (SolO; at R = 0.68 au, ? = E15°), BepiColombo (at R = 0.33 au, ? = W02°), and near-Earth spacecraft, regulated the observed intensity-time profiles and the anisotropic character of the SEP event. PSP, STEREO-A, and SolO detected strong anisotropies at the onset of the SEP event, which resulted from the fact that PSP and STEREO-A were in the declining-speed region of the solar wind stream responsible for the SIR and from the passage of a steady magnetic field structure by SolO during the onset of the event. By contrast, the intensity-time profiles observed near Earth displayed a delayed onset at proton energies ?13 MeV and an accumulation of ?5 MeV protons between the SIR and the shock driven by the parent coronal mass ejection (CME). Even though BepiColombo, STEREO-A, and SolO were nominally connected to the same region of the Sun, the intensity-time profiles at BepiColombo resemble those observed near Earth, with the bulk of low-energy ions also confined between the SIR and the CME-driven shock. This event exemplifies the impact that intervening large-scale interplanetary structures, such as corotating SIRs, have in shaping the properties of SEP events.
2022-07-20T00:00:00Z