104 research outputs found
Ăvolution et transmission des savoir-faire cĂ©ramiques au cours du Sylvicole (-1000 Ă 1550 de notre Ăšre) : la station 3-avant de Pointe-du-Buisson (BhFl-1d), Haut-Saint-Laurent, QuĂ©bec
La station 3-avant de Pointe-du-Buisson (Beauharnois, Haut-Saint-Laurent, QuĂ©bec) reprĂ©sente la plus importante collection de rĂ©cipients de terre cuite datant du Sylvicole moyen ancien (-400 Ă 500 de notre Ăšre) dans le Nord-Est amĂ©ricain. De plus, on trouve sur ce site une sĂ©rie continue dâoccupations couvrant lâensemble de la pĂ©riode Sylvicole. En dĂ©pit de complications dâordre stratigraphique (terreau homogĂšne et pĂ©doturbations), des concepts et des mĂ©thodes Ă©volutionnaires tirĂ©s de la thĂ©orie de lâhĂ©rĂ©ditĂ© duelle sont appliquĂ©s Ă lâĂ©tude de cet assemblage. Dâun point de vue anthropologique, que nous apprend lâĂ©tude de lâĂ©volution et de la transmission des savoir-faire dâune technologie que nous assumons exclusivement fĂ©minine au cours de la pĂ©riode Sylvicole?
Lâauteur dĂ©fend que lâarchĂ©ologie Ă©volutionnaire permet de dĂ©tecter le contexte de la transmission, câest-Ă -dire lâorganisation socioĂ©conomique des populations du passĂ©. Lâexamen des traits stylistiques suggĂšre que la sĂ©dentarisation estivale des bandes amĂ©rindiennes Ă partir du Sylvicole moyen tardif favorise une homogĂ©nĂ©isation des productions cĂ©ramiques dans un contexte virilocal qui est la consĂ©quence dâune transmission de type conformiste opĂ©rant sur un axe horizontal (entre pairs). Cependant, le passage probable des tribus iroquoiennes Ă lâuxorilocalitĂ© et Ă la matrilinĂ©aritĂ© Ă la fin du Sylvicole se traduit par une saisissante hĂ©tĂ©rogĂ©nĂ©isation des pots, qui sâexplique possiblement par une sĂ©lection de marqueurs identitaire dâordre clanique (transmission verticale entre parents et descendants). LâĂ©tude des traits techno-fonctionnels indique une diversification de la vaisselle de terre cuite Ă mesure que les populations intensifient leurs expĂ©riences sur les cultigĂšnes. Dans lâensemble, cette Ă©volution trahit une attention accrue confĂ©rĂ©e Ă la performance des pots en tant que rĂ©cipients culinaires.
Par ailleurs, le concours de la sĂ©riation et de datations AMS permet la reconnaisance dâun taxon « Sylvicole moyen moyen » caractĂ©risĂ© par une modification morphologique et dĂ©corative des vases. Une enquĂȘte comparative portant sur un Ă©chantillon de 27 sites archĂ©ologiques de lâhorizon Pseudo-scallop-shell dĂ©montre que la variation populationnelle est structurĂ©e en fonction de la localisation des communautĂ©s dans un bassin hydrographique spĂ©cifique. Par consĂ©quent, lâauteur soumet des pistes en vue de lâĂ©laboration dâune taxonomie robuste et propre au Sylvicole moyen ancien et au Sylvicole moyen moyen. Enfin, des indices de natures diverses (archĂ©ologiques, palĂ©oethnobotaniques, ethnolinguistiques, palĂ©oanthropologiques, et dâautres issus de la gĂ©nĂ©tique des populations) suggĂšrent une identitĂ© proto-algonquienne des bandes des deux sous-pĂ©riodes susmentionnĂ©es.Station 3-avant at Pointe-du-Buisson (Beauharnois, Haut-Saint-Laurent, Quebec) has produced the most important collection of Early Middle Woodland (400 B.C. â A.D. 500) earthen ware in Northeastern North America. It also contains an uninterrupted sequence of occupations throughout the Woodland Period. Notwithstanding several stratigraphic complications (homogeneous soil and pedoturbations), evolutionary concepts and methods drawn from the Dual Inheritance Theory are applied to this assemblage. From an anthropological standpoint, what does the study of the evolution and the transmission of know-how pertaining to a Woodland period technology, which we assume to be exclusively feminine, tell us?
The author defends that evolutionary archaeology may help detect the context of transmission, i.e. the socioeconomic organization of past populations. The examination of stylistic traits suggests that the progressive summertime sedentarization of amerindian bands, starting around the Late Middle Woodland period, favours a homogenization of ceramics in the context of virilocality, which is the consequence of a conformist-biased transmission operating on a horizontal axis (between peers). However, the probable transition to uxorilocality and to matrilinearity by Iroquoian tribes at the end of the Woodland Period manifests itself through an obvious heterogenization of ceramics, which is likely to reflect a form of cultural selection targeting clanic markers (vertical transmission between parents and offsprings). The study of techno-functional traits indicates a diversification of the ceramic tool-kit following an intensification of experimentation with cultigens. Overall, this evolution underlines a greater attention given to the performance of pots as culinary tools.
Additionally, the recourse to seriation and AMS datation allows for the recognition of a Middle Middle Woodland taxon that is characterized by both morphological and decorative modifications of pots. A comparative analysis involving a sample of 27 archaeological sites belonging in the Pseudo-scallop-shell Horizon further demonstrates that the populational variation comprised within this dataset is structured according to the geographic localization of sites in specific drainages. Consequently, the author outlines guidelines for the elaboration of a proper taxonomy with respect to both Early Middle Woodland and Middle Middle Woodland taxa. Finally, arguments drawn from diverse fields (archaeology, palaeoethnobotany, ethnolinguistics, palaeonanthropology and population genetics) point towards a proto-algonquian identity for the aforementioned taxa
VariabilitĂ© stylistique des occupations du Sylvicole moyen ancien (400 av. n.Ăš. â 500 de n.Ăš.) sur la station 3-arriĂšre de Pointe-du-Buisson : approche typologique
Ce mĂ©moire porte sur la variabilitĂ© observĂ©e dans un assemblage, composĂ© Ă la fois dâartĂ©facts lithiques et cĂ©ramiques, reprĂ©sentatif de la plus grande collection archĂ©ologique dominĂ©e par une composante du Sylvicole moyen ancien connue au QuĂ©bec. Les traits caractĂ©ristiques des poteries qui ont Ă©tĂ© transportĂ©es, abandonnĂ©es, et en partie manufacturĂ©es sur la station 3-arriĂšre du complexe de Pointe-du-Buisson, sont apprĂ©hendĂ©s Ă travers une acception holistique de la notion de «style», qui inclut tous les aspects des attributs quâelle couvre, Ă savoir les technologiques, les morphologiques, les dĂ©coratifs et les fonctionnels. GrĂące Ă lâapplication dâune mĂ©thode typologique, une approche peu utilisĂ©e depuis plusieurs dĂ©cennies, du moins dans le Nord-Est amĂ©ricain, et dont le mĂ©rite propre rĂ©side dans sa capacitĂ© Ă traiter lâartĂ©fact dans son ensemble, des schĂ©mas comportementaux (cognitifs et procĂ©duraux) visibles sur les tessons de bord dĂ©corĂ©s ont Ă©tĂ© mis en lumiĂšre. Ces derniers sont intimement liĂ©s aux techniques dĂ©coratives employĂ©es par les potiĂšres, et semblent sâĂȘtre modifiĂ©s au fil du temps de la maniĂšre suivante : type «sigillé» prĂ©cĂ©dant les types plus rĂ©cents «repoussé» et «basculant».
Une analyse comparative, basĂ©e sur un Ă©chantillon de sites localisĂ©s dans la rĂ©gion de Haut-Saint-Laurent et dans celles avoisinantes, a par ailleurs soulignĂ© dâimportantes similaritĂ©s entre lâassemblage cĂ©ramique de la composante du Sylvicole moyen ancien de BhFl-1dâ et ceux des sites de Vieux-Pont (Estrie), dâOka (riviĂšre des Outaouais), de Pointe-du-Gouvernement (Haut-Richelieu) et de Winooski (aux abords du Lac Champlain dans le Vermont). Ces rĂ©sultats appuient lâidentification dâune manifestation culturelle qui est trĂšs Ă©troitement connectĂ©e aux phases Canoe Point et Winooski de la tradition Point Peninsula.
RĂ©sultant des conclusions susmentionnĂ©es, et dâautres issues dâenquĂȘtes rĂ©centes, des considĂ©rations dâordre taxonomique sâensuivent. Bien quâune refonte complĂšte du taxon «Sylvicole moyen» soit prĂ©maturĂ©e, une critique de ce taxon sâavĂšre nĂ©cessaire. Aussi des taxons tels que lâEarly Horticultural Period de Snow ou le «Sylvicole initial» de Wright et Clermont sont discutĂ©s, dans la mesure oĂč ils pourraient renvoyer Ă une dĂ©finition plus gĂ©nĂ©rale, mais aussi peut-ĂȘtre plus fidĂšle, des caractĂ©ristiques anthropologiques propres aux populations qui ont vĂ©cu le long du Saint-Laurent et de ses tributaires depuis le Sylvicole infĂ©rieur jusquâĂ la fin du Sylvicole moyen tardif.This thesis focuses on the variability observed within an assemblage, made up of lithic and ceramic artefacts, that is felt to be representative of the largest collection dominated by an Early Middle Woodland component known in Quebec. The characteristic traits of the pots transported, discarded, and partly manufactured on the station 3-arriĂšre of the Pointe-du-Buisson complex, are apprehended via a holistic understanding of the notion of «style» which includes all aspects of the attributes it covers, i.e. technological, morphological, decorative and functional ones. Thanks to the application of a typological method, a long forsaken approach, at least in eastern north America, whose specific merit resides in its ability to treat the artefact as a whole, behavioural (cognitive and procedural) patterns visible on the decorated rim sherds have been identified. These are intimately related to the decorative techniques used by the makers, and seem to have changed through time as follows: «vertical or simple» type, preceding the more recent «push-pull» and «rocker-stamp» types.
A comparative analysis, based on a sample of sites located in the Upper St-Lawrence and neighbouring regions, has also revealed great similarities between the ceramic assemblage of the Early Middle Woodland component of BhFl-1dâ and those of Vieux-Pont (Eastern Townships, QC), Oka (Ottawa River), Pointe-du-Gouvernement (Upper Richelieu) and Winooski (Lake Champlain area, Vermont) sites. These results argue for the existence of a cultural manifestation that is very closely related to both the Canoe Point and Winooski phases of the Point Peninsula tradition.
Following the aforementioned conclusions and based on others resulting from recent inquiries, further taxonomic considerations have emerged. While a complete overhaul of the Middle Woodland pattern would be premature, rethinking this taxon appears necessary. Therefore, taxa such as Early Horticultural Period (Snow) or Initial Woodland (Wright, Clermont) are revived and discussed since they may prove to be useful in defining more general, but also maybe more appropriate, anthropological traits concerning the populations that lived along the Saint Lawrence River and its tributaries from the Early Woodland to the end of the Late Middle Woodland
The exceptionally powerful TeV gamma-ray emitters in the Large Magellanic Cloud
The Large Magellanic Cloud, a satellite galaxy of the Milky Way, has been
observed with the High Energy Stereoscopic System (H.E.S.S.) above an energy of
100 billion electron volts for a deep exposure of 210 hours. Three sources of
different types were detected: the pulsar wind nebula of the most energetic
pulsar known N 157B, the radio-loud supernova remnant N 132D and the largest
non-thermal X-ray shell - the superbubble 30 Dor C. The unique object SN 1987A
is, surprisingly, not detected, which constrains the theoretical framework of
particle acceleration in very young supernova remnants. These detections reveal
the most energetic tip of a gamma-ray source population in an external galaxy,
and provide via 30 Dor C the unambiguous detection of gamma-ray emission from a
superbubble.Comment: Published in Science Magazine (Jan. 23, 2015). This ArXiv version has
the supplementary online material incorporated as an appendix to the main
pape
Constraints on axionlike particles with H.E.S.S. from the irregularity of the PKS 2155-304 energy spectrum
Axionlike particles (ALPs) are hypothetical light (sub-eV) bosons predicted in some extensions of the Standard Model of particle physics. In astrophysical environments comprising high-energy gamma rays and turbulent magnetic fields, the existence of ALPs can modify the energy spectrum of the gamma rays for a sufficiently large coupling between ALPs and photons. This modification would take the form of an irregular behavior of the energy spectrum in a limited energy range. Data from the H.E.S.S. observations of the distant BL Lac object PKS 2155-304 (z=0.116) are used to derive upper limits at the 95% C.L. on the strength of the ALP coupling to photons, ggammaa<2.1Ă10-11GeV-1 for an ALP mass between 15 and 60 neV. The results depend on assumptions on the magnetic field around the source, which are chosen conservatively. The derived constraints apply to both light pseudoscalar and scalar bosons that couple to the electromagnetic fieldFil: Medina, Maria Clementina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico La Plata. Instituto Argentino de Radioastronomia (i); ArgentinaFil: H.E.S. S. collaboration
Diffuse Galactic gamma-ray emission with H.E.S.S
Diffuse Îł-ray emission is the most prominent observable signature of celestial cosmic-ray interactions at high energies. While already being investigated at GeV energies over several decades, assessments of diffuse Îł-ray emission at TeV energies remain sparse. After completion of the systematic survey of the inner Galaxy, the H.E.S.S. experiment is in a prime position to observe large-scale diffuse emission at TeV energies. Data of the H.E.S.S. Galactic Plane Survey are investigated in regions off known Îł-ray sources. Corresponding Îł-ray flux measurements were made over an extensive grid of celestial locations. Longitudinal and latitudinal profiles of the observed Îł-ray fluxes show characteristic excess emission not attributable to known Îł-ray sources. For the first time large-scale Îł-ray emission along the Galactic plane using imaging atmospheric Cherenkov telescopes has been observed. While the background subtraction technique limits the ability to recover modest variation on the scale of the H.E.S.S. field of view or larger, which is characteristic of the inverse Compton scatter-induced Galactic diffuse emission, contributions of neutral pion decay as well as emission from unresolved Îł-ray sources can be recovered in the observed signal to a large fraction. Calculations show that the minimum Îł-ray emission from Ï0 decay represents a significant contribution to the total signal. This detection is interpreted as a mix of diffuse Galactic Îł-ray emission and unresolved sources
Probing the gamma-ray emission from HESS J1834-087 using H.E.S.S. and Fermi LAT observations
Aims. Previous observations with the High Energy Stereoscopic System (H.E.S.S.) have revealed an extended very-high-energy (VHE; E> 100 GeV) Îł-ray source, HESS J1834â087, coincident with the supernova remnant (SNR) W41. The origin of the Îł-ray emission was investigated in more detail with the H.E.S.S. array and the Large Area Telescope (LAT) onboard the Fermi Gamma-ray Space Telescope. Methods. The Îł-ray data provided by 61 h of observations with H.E.S.S., and four years with the Fermi LAT were analyzed, covering over five decades in energy from 1.8 GeV up to 30 TeV. The morphology and spectrum of the TeV and GeV sources were studied and multiwavelength data were used to investigate the origin of the Îł-ray emission toward W41. Results. The TeV source can be modeled with a sum of two components: one point-like and one significantly extended (ÏTeV = 0.17° ± 0.01°), both centered on SNR W41 and exhibiting spectra described by a power law with index ÎTeV â 2.6. The GeV source detected with Fermi LAT is extended (ÏGeV = 0.15° ± 0.03°) and morphologically matches the VHE emission. Its spectrum can be described by a power-law model with an index ÎGeV = 2.15 ± 0.12 and smoothly joins the spectrum of the whole TeV source. A break appears in the Îł-ray spectra around 100 GeV. No pulsations were found in the GeV range. Conclusions. Two main scenarios are proposed to explain the observed emission: a pulsar wind nebula (PWN) or the interaction of SNR W41 with an associated molecular cloud. X-ray observations suggest the presence of a point-like source (a pulsar candidate) near the center of the remnant and nonthermal X-ray diffuse emission that could arise from the possibly associated PWN. The PWN scenario is supported by the compatible positions of the TeV and GeV sources with the putative pulsar. However, the spectral energy distribution from radio to Îł-rays is reproduced by a one-zone leptonic model only if an excess of low-energy electrons is injected following a Maxwellian distribution by a pulsar with a high spin-down power (>1037 erg s-1). This additional low-energy component is not needed if we consider that the point-like TeV source is unrelated to the extended GeV and TeV sources. The interacting SNR scenario is supported by the spatial coincidence between the Îł-ray sources, the detection of OH (1720 MHz) maser lines, and the hadronic modeling
Discovery of the Hard Spectrum VHE Îł-Ray Source HESS J1641-463
This Letter reports the discovery of a remarkably hard spectrum source, HESS J1641â463, by the High Energy Stereoscopic System (H.E.S.S.) in the very high energy (VHE) domain. HESS J1641â463 remained unnoticed by the usual analysis techniques due to confusion with the bright nearby source HESS J1640â465. It emerged at a significance level of 8.5 standard deviations after restricting the analysis to events with energies above 4 TeV. It shows a moderate flux level of phgr(E>1âTeV) = (3.64 ± 0.44stat ± 0.73sys) Ă 10â13âcmâ2âsâ1, corresponding to 1.8% of the Crab Nebula flux above the same energy, and a hard spectrum with a photon index of Î = 2.07 ± 0.11stat ± 0.20sys. It is a point-like source, although an extension up to a Gaussian width of Ï = 3 arcmin cannot be discounted due to uncertainties in the H.E.S.S. point-spread function. The VHE Îł-ray flux of HESS J1641â463 is found to be constant over the observed period when checking time binnings from the year-by-year to the 28 minute exposure timescales. HESS J1641â463 is positionally coincident with the radio supernova remnant SNR G338.5+0.1. No X-ray candidate stands out as a clear association; however, Chandra and XMM-Newton data reveal some potential weak counterparts. Various VHE Îł-ray production scenarios are discussed. If the emission from HESS J1641â463 is produced by cosmic ray protons colliding with the ambient gas, then their spectrum must extend close to 1 PeV. This object may represent a source population contributing significantly to the galactic cosmic ray flux around the knee
The 2010 very high energy gamma-ray flare & 10 years of multi-wavelength observations of M 87
Abridged: The giant radio galaxy M 87 with its proximity, famous jet, and
very massive black hole provides a unique opportunity to investigate the origin
of very high energy (VHE; E>100 GeV) gamma-ray emission generated in
relativistic outflows and the surroundings of super-massive black holes. M 87
has been established as a VHE gamma-ray emitter since 2006. The VHE gamma-ray
emission displays strong variability on timescales as short as a day. In this
paper, results from a joint VHE monitoring campaign on M 87 by the MAGIC and
VERITAS instruments in 2010 are reported. During the campaign, a flare at VHE
was detected triggering further observations at VHE (H.E.S.S.), X-rays
(Chandra), and radio (43 GHz VLBA). The excellent sampling of the VHE gamma-ray
light curve enables one to derive a precise temporal characterization of the
flare: the single, isolated flare is well described by a two-sided exponential
function with significantly different flux rise and decay times. While the
overall variability pattern of the 2010 flare appears somewhat different from
that of previous VHE flares in 2005 and 2008, they share very similar
timescales (~day), peak fluxes (Phi(>0.35 TeV) ~= (1-3) x 10^-11 ph cm^-2
s^-1), and VHE spectra. 43 GHz VLBA radio observations of the inner jet regions
indicate no enhanced flux in 2010 in contrast to observations in 2008, where an
increase of the radio flux of the innermost core regions coincided with a VHE
flare. On the other hand, Chandra X-ray observations taken ~3 days after the
peak of the VHE gamma-ray emission reveal an enhanced flux from the core. The
long-term (2001-2010) multi-wavelength light curve of M 87, spanning from radio
to VHE and including data from HST, LT, VLA and EVN, is used to further
investigate the origin of the VHE gamma-ray emission. No unique, common MWL
signature of the three VHE flares has been identified.Comment: 19 pages, 5 figures; Corresponding authors: M. Raue, L. Stawarz, D.
Mazin, P. Colin, C. M. Hui, M. Beilicke; Fig. 1 lightcurve data available
online: http://www.desy.de/~mraue/m87
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