114 research outputs found
Was the GLE on May 17, 2012 linked with the M5.1-class flare the first in the 24th solar cycle?
On May 17, 2012 an M5.1-class flare exploded from the sun. An O-type coronal
mass ejection (CME) was also associated with this flare. There was an instant
increase in proton flux with peak at MeV, leading to S2 solar
radiation storm level. In about 20 minutes after the X-ray emission, the solar
particles reached the Earth.It was the source of the first (since December
2006) ground level enhancement (GLE) of the current solar cycle 24. The GLE was
detected by neutron monitors (NM) and other ground based detectors. Here we
present an observation by the Tupi muon telescopes (Niteroi, Brazil, , , 3 m above sea level) of the enhancement of muons at ground
level associated with this M5.1-class solar flare. The Tupi telescopes
registered a muon excess over background in the 5-min binning time
profile. The Tupi signal is studied in correlation with data obtained by
space-borne detectors (GOES, ACE), ground based neutron monitors (Oulu) and air
shower detectors (the IceTop surface component of the IceCube neutrino
observatory). We also report the observation of the muon signal possibly
associated with the CME/sheath striking the Earth magnetosphere on May 20,
2012. We show that the observed temporal correlation of the muon excess
observed by the Tupi muon telescopes with solar transient events suggests a
real physical connection between them. Our observation indicates that
combination of two factors, the low energy threshold of the Tupi muon
telescopes and the location of the Tupi experiment in the South Atlantic
Anomaly region, can be favorable in the study and detection of the solar
transient events. Our experiment provides new data complementary to other
techniques (space and ground based) in the study of solar physics.Comment: 9 pages, 10 figure
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Religious transformations in the Middle Ages: towards a new archaeological agenda
The study of religious change in Europe between the collapse of the Roman Empire and the Reformation forms one of the cornerstones of medieval archaeology but has been riven by period, denominational and geographical divisions. This paper lays the groundwork for a fundamental rethink of archaeological approaches to medieval religions, by adopting a holistic framework that places Christian, pagan, Islamic and Jewish case studies of religious transformation in a long-term, comparative perspective. Focused around the analytical themes of ‘hybridity and resilience’ and ‘tempo and trajectories’, our approach shifts attention away from the singularities of national narratives of religious conversion towards a deeper understanding of how religious beliefs, practices and identity were renegotiated by medieval people in their daily lives
a multi scalar approach to long term dynamics spatial relations and economic networks of roman secondary settlements in italy and the ombrone valley system southern tuscany towards a model
In Roman landscapes, the particular sites defined as secondary settlements (also known as vici/villages, minor centres, agglomerations secondaires and/or stationes/mansiones) have played an 'intermediary' role between the cities and other rural structures (villae/farms), linked to medium- and long-distance economic and commercial trajectories. The aim of this paper is to apply a multi-scalar approach to model their long-term spatial relationships and connectivity with the Mediterranean exchange network. On the macro-scale, we have analysed a sample of 219 reviewed sites to understand the diachronic trends and spatial dynamics of attraction/proximity to significant elements of the landscape such as towns, roads, rivers and coastline. The Ombrone Valley (Tuscany, Italy) represents a micro-scale case study of a complex system, in which the imported pottery (amphorae, African Red Slip ware, ingobbiata di rosso) found in the vicus/mansio of Santa Cristina in Caio, the Roman villa of La Befa and the town of Siena (Saena Iulia) provided diagnostic 'macroeconomic' perspectives. The results show how the secondary settlements occupied a nodal position in the Roman landscape in terms of resilience (long period of occupation until the Early Middle Ages) and spatial organization with a close relationship to natural and anthropic infrastructures and trade functions linked to Mediterranean routes
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