50 research outputs found
Montlleó (Prats i Sansor, Lérida, Espagne) : le passage du symbolisme à travers les montagnes
Le site de plein air de Montlleó (Prats i Sansor, Lérida, Espagne) est situé sur une petite colline de la haute vallée du Sègre, au cœur de la plaine de la Cerdagne, sur un axe stratégique de communication – ou couloir – qui connecte les deux versants des Pyrénées. Les caractéristiques culturelles des industries lithiques et les dates radiocarbone nous démontrent l’âge ancien des occupations humaines sur cette partie méridionale des Pyrénées orientales. Le site de Montlleó se caractérise par la quantité et la variété des éléments culturels, que nous pouvons mettre en relation avec l’univers symbolique de ces populations de chasseurs-cueilleurs. Ces évidences matérielles sont exploitées dans cet article pour étudier le comportement symbolique des populations de la fin du Paléolithique supérieur. Les marqueurs sont répartis en trois types : la parure, dans le sens traditionnel du terme, les minéraux rares apportés sur le site, et enfin les matières colorantes.The open-air site of Montlleó (Prats i Sansor, Lérida, Spain) is located on a small hill in the upper valley of the Segre River, in the center of the Cerdanya plain, on a strategic axis of communication –or corridor– connecting both sides of the Pyrenees. The cultural features of the lithic industries and the radiocarbon dates are indicating the old age of the human occupations in this southern part of the eastern Pyrenees. The site is characterized by the quantity and variety of cultural elements that can be related to the symbolic sphere of these hunter-gatherer populations. In the present research we analyze this material evidence in relation to the symbolic behavior of the late Upper Paleolithic populations. In this regard, we study three types of markers: ornaments, in the traditional meaning of the term; rare minerals brought to the site; and dyestuffs of several hues
The Middle-to-Upper Paleolithic transition occupations from Cova Foradada (Calafell, NE Iberia)
The Middle-to-Upper Paleolithic transition in Europe covers the last millennia of Neanderthal life together with the appearance and expansion of Modern Human populations. Culturally, it is defined by the Late Middle Paleolithic succession, and by Early Upper Paleolithic complexes like the Châtelperronian (southwestern Europe), the Protoaurignacian, and the Early Aurignacian. Up to now, the southern boundary for the transition has been established as being situated between France and Iberia, in the Cantabrian façade and Pyrenees. According to this, the central and southern territories of Iberia are claimed to have been the refuge of the last Neanderthals for some additional millennia after they were replaced by anatomically Modern Humans on the rest of the continent. In this paper, we present the Middle-to-Upper Paleolithic transition sequence from Cova Foradada (Tarragona), a cave on the Catalan Mediterranean coastline. Archaeological research has documented a stratigraphic sequence containing a succession of very short-term occupations pertaining to the Châtelperronian, Early Aurignacian, and Gravettian. Cova Foradada therefore represents the southernmost Châtelperronian-Early Aurignacian sequence ever documented in Europe, significantly enlarging the territorial distribution of both cultures and providing an important geographical and chronological reference for understanding Neanderthal disappearance and the complete expansion of anatomically Modern Humans
The Châtelperronian Neanderthals of Cova Foradada (Calafell, Spain) used imperial eagle phalanges for symbolic purposes
Evidence for the symbolic behavior of Neanderthals in the use of personal ornaments is relatively scarce. Among the few ornaments documented, eagle talons, which were presumably used as pendants, are the most frequently recorded. This phenomenon appears concentrated in a specific area of southern Europe during a span of 80 thousand years. Here, we present the analysis of one eagle pedal phalange recovered from the Châtelperronian layer of Foradada Cave (Spain). Our research broadens the known geographical and temporal range of this symbolic behavior, providing the first documentation of its use among the Iberian populations, as well as of its oldest use in the peninsula. The recurrent appearance of large raptor talons throughout the Middle Paleolithic time frame, including their presence among the last Neanderthal populations, raises the question of the survival of some cultural elements of the Middle Paleolithic into the transitional Middle to Upper Paleolithic assemblages and beyond
SDSS-IV MaNGA : spatial evolution of star formation triggered by galaxy interactions
Galaxy interaction is considered a key driver of galaxy evolution and star formation (SF) history. In this paper, we present an empirical picture of the radial extent of interaction-triggered SF along the merger sequence. The samples under study are drawn from the integral field spectroscopy survey SDSS-IV MaNGA, including 205 star-forming galaxies in pairs/mergers and ~1350 control galaxies. For each galaxy in pairs, the merger stage is identified according to its morphological signatures: incoming phase, at first pericenter passage, at apocenter, in merging phase, and in final coalescence. The effect of interactions is quantified by the global and spatially resolved SF rate (SFR) relative to the SFR of a control sample selected for each individual galaxy (Δlog SFR and Δlog sSFR(r), respectively). Analysis of the radial Δlog sSFR(r) distributions shows that galaxy interactions have no significant impact on Δlog sSFR(r) during the incoming phase. Right after the first pericenter passage, the radial Δlog sSFR(r) profile decreases steeply from enhanced to suppressed activity for increasing galactocentric radius. Later on, SF is enhanced on a broad spatial scale out to the maximum radius we explore (~6.7 kpc) and the enhancement is in general centrally peaked. The extended SF enhancement is also observed for systems at their apocenters and in the coalescence phase, suggesting that interaction-triggered SF is not restricted to the central region of a galaxy. Further explorations of a wide range in parameter space of merger configurations (e.g., mass ratio) are required to constrain the whole picture of interaction-triggered S
The 13th data release of the Sloan Digital Sky Survey: first spectroscopic data from the SDSS-IV survey mapping nearby galaxies at Apache Point Observatory
The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) began observations in 2014 July. It pursues three core programs: the Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2), Mapping Nearby Galaxies at APO (MaNGA), and the Extended Baryon Oscillation Spectroscopic Survey (eBOSS). As well as its core program, eBOSS contains two major subprograms: the Time Domain Spectroscopic Survey (TDSS) and the SPectroscopic IDentification of ERosita Sources (SPIDERS). This paper describes the first data release from SDSS-IV, Data Release 13 (DR13). DR13 makes publicly available the first 1390 spatially resolved integral field unit observations of nearby galaxies from MaNGA. It includes new observations from eBOSS, completing the Sloan Extended QUasar, Emission-line galaxy, Luminous red galaxy Survey (SEQUELS), which also targeted variability-selected objects and X-ray-selected objects. DR13 includes new reductions of the SDSS-III BOSS data, improving the spectrophotometric calibration and redshift classification, and new reductions of the SDSS-III APOGEE-1 data, improving stellar parameters for dwarf stars and cooler stars. DR13 provides more robust and precise photometric calibrations. Value-added target catalogs relevant for eBOSS, TDSS, and SPIDERS and an updated red-clump catalog for APOGEE are also available. This paper describes the location and format of the data and provides references to important technical papers. The SDSS web site, http://www.sdss.org, provides links to the data, tutorials, examples of data access, and extensive documentation of the reduction and analysis procedures. DR13 is the first of a scheduled set that will contain new data and analyses from the planned ~6 yr operations of SDSS-IV
Molecular Gas and Star Formation Properties in Early Stage Mergers:SMA CO(2-1) Observations of the LIRGs NGC 3110 and NGC 232
Mergers of galaxies are an important mode for galaxy evolution because they
serve as an efficient trigger of powerful starbursts. However, observational
studies of the molecular gas properties during their early stages are scarce.
We present interferometric CO(2-1) maps of two luminous infrared galaxies
(LIRGs), NGC 3110 and NGC 232, obtained with the Submillimeter Array (SMA) with
~ 1 kpc resolution. While NGC 3110 is a spiral galaxy interacting with a minor
(14:1 stellar mass) companion, NGC 232 is interacting with a similarly sized
object. We find that such interactions have likely induced in these galaxies
enhancements in the molecular gas content and central concentrations, partly at
the expense of atomic gas. The obtained molecular gas surface densities in
their circumnuclear regions are M
pc, higher than in non-interacting objects by an order of magnitude. Gas
depletion times of ~ 0.5 - 1 Gyr are found for the different regions, lying in
between non-interacting disk galaxies and the starburst sequence. In the case
of NGC 3110, the spiral arms show on average 0.5 dex shorter depletion times
than in the circumnuclear regions if we assume a similar H-CO conversion
factor. We show that even in the early stages of the interaction with a minor
companion, a starburst is formed along the circumnuclear region and spiral
arms, where a large population of SSCs is found (~350), and at the same time a
large central gas concentration is building up which might be the fuel for an
active galactic nucleus. The main morphological properties of the NGC 3110
system are reproduced by our numerical simulations and allow us to estimate
that the current epoch of the interaction is at ~ 150 Myrs after closest
approach.Comment: 30 pages. Accepted for publication in Ap
The 13th Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-IV Survey Mapping Nearby Galaxies at Apache Point Observatory
The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) began observations in 2014 July. It pursues three core programs: the Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2), Mapping Nearby Galaxies at APO (MaNGA), and the Extended Baryon Oscillation Spectroscopic Survey (eBOSS). As well as its core program, eBOSS contains two major subprograms: the Time Domain Spectroscopic Survey (TDSS) and the SPectroscopic IDentification of ERosita Sources (SPIDERS). This paper describes the first data release from SDSS-IV, Data Release 13 (DR13). DR13 makes publicly available the first 1390 spatially resolved integral field unit observations of nearby galaxies from MaNGA. It includes new observations from eBOSS, completing the Sloan Extended QUasar, Emission-line galaxy, Luminous red galaxy Survey (SEQUELS), which also targeted variability-selected objects and X-ray-selected objects. DR13 includes new reductions of the SDSS-III BOSS data, improving the spectrophotometric calibration and redshift classification, and new reductions of the SDSS-III APOGEE-1 data, improving stellar parameters for dwarf stars and cooler stars. DR13 provides more robust and precise photometric calibrations. Value-added target catalogs relevant for eBOSS, TDSS, and SPIDERS and an updated red-clump catalog for APOGEE are also available. This paper describes the location and format of the data and provides references to important technical papers. The SDSS web site, http://www.sdss.org, provides links to the data, tutorials, examples of data access, and extensive documentation of the reduction and analysis procedures. DR13 is the first of a scheduled set that will contain new data and analyses from the planned ~6 yr operations of SDSS-IV