Ho-Hin Leung, Adam C. Carnall, Elizabeth Taylor
et al.
We present deep, medium-resolution $λ=1-5\,μ$m JWST/NIRSpec spectroscopy for 14 quiescent galaxies at $3<z<5$ with $\log_{10}(M_*/\mathrm{M_\odot}){\,>\,}10$, obtained as part of the EXCELS survey. We perform a complete re-reduction of these data, including a custom optimal-extraction approach to combat the spectral "wiggles" that result from undersampling of the NIRSpec spatial PSF. We constrain the star-formation histories and stellar metallicities of these objects via full-spectral fitting, finding a clear stellar age vs stellar mass correlation, in which more massive galaxies assembled their stellar mass at earlier times. This confirms spectroscopically that the archaeological "downsizing" trend was already in place by $z\simeq4$. The slope of our measured relation ($\simeq1.5$ Gyr per dex in stellar mass) is consistent with literature results at $0 < z < 3$. We do not observe objects with $\log_{10}(M_*/\mathrm{M_\odot})\lesssim10.5$ and ages of more than a few hundred Myr at this epoch, suggesting that recently reported examples of higher-redshift quiescent galaxies at these masses are likely to soon rejuvenate. We measure relatively high stellar metallicities for the majority of our sample, consistent with similar objects at $0 < z < 3$. Finally, we explore evidence for $α$-enhancement in six older and more luminous galaxies within our sample, finding considerable disagreements in the chemical abundances measured using different stellar population models, different fitted rest-frame wavelength ranges, star-formation history models and fitting codes. We therefore conclude that inferring detailed stellar chemical abundances for the earliest quiescent galaxies remains challenging, and higher signal-to-noise spectra are required (SNR per resolution element $>100$ for $R\simeq1000$).
Jerry Jun-Yan Zhang, Nicolas Lodieu, Eduardo L. Martín
et al.
The coldest metal-poor population made of T and Y dwarfs are archaeological tracers of our Galaxy because they are very old and have kept the pristine material. The optical properties of these objects are important to characterise their atmospheric properties. We aim at characterising further the optical properties of ultracool metal-poor population with deep far-red optical images and parallax determinations. With a two-year baseline, we solved trigonometric parallaxes of the five metal-poor T dwarf candidates using Calar-Alto 3.5-m telescope. We obtained $z'$-band photometry for the other 12 metal-poor T dwarf candidates using 10.4-m Gran Telescopio Canarias, the 8.2-m European Southern Observatory Very Large Telescope, and the Dark Energy Survey, increasing the sample of T subdwarfs with optical photometry from 12 to 24. We report a 3-$σ$ limit for the only potential metal-poor Y dwarf, a.k.a., the Accident in five optical bands using the Gran Telescopio Canarias. We compared these objects with a known subdwarf benchmark and solar-metallicity dwarfs in colour-magnitude and colour-colour diagrams, as well as with state-of-the-art theoretical ultracool models. We confirm three more T subdwarfs and show that the Accident is subluminous compared to the current Y dwarf limit. Additionally, we propose two more Y subdwarf candidates. We emphasise that the $z_{PS1} - W1$ colour combining with the $W1 - W2$ colour could break the metallicity-temperature degeneracy for T and possibly for Y dwarfs. The $z_{PS1} - W1$ colour shifts redward when metallicity decreases for a certain temperature, which is not predicted by models. The Accident has the reddest $z_{PS1} - W1$ colour among our sample. The $z_{PS1} - W1$ colour will be useful to search for other examples of this cold and old population in upcoming and existing deep optical and infrared large-area surveys.
The study of the relationships between prehistoric social groups is one of the main targets in present day archaeology. A useful tool to entangle this issue is social network analysis (SNA). Some of the advantages brought by this mathematic approach refer to the possibility of studying relationships through the material culture items, or its capability to integrate different scales of analysis (macro-micro). Moreover, SNA combined with the application of bayesian statistical methods of chronological attribution can create long range diachronic series of relational information, connected with prehistoric social groups dynamics. This methodology enables archaeologists to study archaeological big data from a totally different perspective, not only focused on a descriptive or morphometric point of view. The objective of this work is to apply an SNA procedure, together with a recently developed bayesian tool of chronological attribution, to archaeological sites located in the East of the Iberian Peninsula during the 4th and 3rd millennium cal. BCE using chert arrowheads as an archaeological proxy, due to the chronologic implications their morphology has, in the referred geographic frame. It is our specific target to analyse the transition between the Bell-Beaker world and the Bronze Age, through the differential transmission of information and the time-space variability present in the archaeological record, through the study of relationships between chert arrowheads assemblages. In order to do so, we will build a relational framework between the social communities present in the Late Neolithic-Copper Age through the chert arrowheads morphologic typologies, and we will apply SNA to characterize the resulting networks. Furthermore, we will propose a new metric to quantify the cultural fragmentation using community detection algorithms, in a diachronic axis, to identify groups of sites with homogeneous technological behaviour, to check the initial hypothesis which points to the existence of periods of cultural homogeneity followed by others in which fragmentation-regionalization is dominant.
Elisabeth Trinkl, Stephan Karl, Stefan Lengauer
et al.
This paper focuses on digitally-supported research methods for an important group of cultural heritage objects, the Greek pottery, especially with figured decoration. The design, development and application of new digital methods for searching, comparing, and visually exploring these vases needs an interdisciplinary approach to effectively analyse the various features of the vases, like shape, decoration, and manufacturing techniques, and relationships between the vases. We motivate the need and opportunities by a multimodal representation of the objects, including 3D shape, material, and painting. We then illustrate a range of innovative methods for these representations, including quantified surface and capacity comparison, material analysis, image flattening from 3D objects, retrieval and comparison of shapes and paintings, and multidimensional data visualization. We also discuss challenges and future work in this area.
Michel Justamand, Pedro Paulo Funari, Marcelia Marques
et al.
This essay aims to present some sexual representations in rock art in the Serra da Capivara National Park (PNSC), in southeastern Piauí, Brazil. Since immemorial times, humans have created ways to express themselves, and rock art, engravings and/or paintings were sociocultural forms found to store and safeguard the most varied everyday information of group interests. More than 1,000 archaeological sites are known in the park, representing subjects related to the sociability of ancestral life, such as hunting, gathering, fighting, ceremonies, sexualities and much more. These depictions have been studied since the 1970’s and allowed the creation of a national park recognized as a World Heritage site. Although the paintings depict scenes considered by Western observers as obscene, barbaric and immoral, it is necessary to remember that primitive sexuality was not separate, private subject, to be hidden from the eyes of the social human life, as it is considered by us in 21st century. Key words: sexuality, rock art, prehistoric life, Serra da Capivara National Park, Piauí.
The origin of non-alkaline lead-silica (PbO•SiO2) and lead-potassium-silica
(PbO•K2O•SiO2) glass-forming technologies, which many Russian researchers believe to be typical of
ancient Russian glassmaking and attesting to independent glassmaking in early 11th c. Rus’, is discussed
in this paper, limited to a few selected aspects of the issue. Research has proposed two sources of these
technologies adopted in Rus’: Byzantium (Shchapova, Noonan) and, in the case of the first one, the
Far East (Brill). The number of discoveries of glasses of these two chemical types, both artifacts and
production waste, from Europe as well as from the Far East in particular, has grown in the past few
dozen years. New studies presenting the results of chemical composition analyses of glasses of these
types have also increased exponentially. The growing body of data substantiates a return to the subject
of the origins of ancient Rus’ glassmaking. The research should be based on a comparative analysis
of the results of laboratory tests of remains from workshops of type A (with full production cycles
attested) as well as ready products found in ancient Rus’ and in other regions, especially in the Far East.
Auxiliary sciences of history, Prehistoric archaeology
Thomas GARCIA-FERMET, Agnès TESTU, Anne-Marie MOIGNE
et al.
Avian remains are commonly found in Pleistocene cave sites. La Crouzade Cave (Gruissan, Aude, Southern France) is no exception, as it yielded thousands of bird bones recovered from the Middle and Upper Palaeolithic deposits. In Mousterian layers 8, 7 and 6 (MIS 3) the avifaunal spectrum is dominated by cliff-nesting taxa such as doves and corvids from the genus Pyrrhocorax. Some of these birds may have died naturally in situ but the presence of digestive damage on a great number of specimens indicates that most of the individuals were consumed by non-human predators (carnivorous mammals and raptors). Furthermore, the presence of a few cut-marked specimens suggests that Neanderthals took part in the accumulation. Striae located on wing bones such as ulna could be linked to feather removal. The bird assemblage from La Crouzade thus provides a new example of mixed accumulation in which Middle Palaeolithic human populations were involved.
The Milky Way's satellite galaxies ("surviving dwarfs") have been studied for decades as unique probes of chemical evolution in the low-mass regime. Here we extend such studies to the "disrupted dwarfs", whose debris constitutes the stellar halo. We present abundances ([Fe/H], [$α$/Fe]) and stellar masses for nine disrupted dwarfs with $M_{\star}\approx10^{6}-10^{9}M_{\odot}$ from the H3 Survey (Sagittarius, $Gaia$-Sausage-Enceladus, Helmi Streams, Sequoia, Wukong/LMS-1, Cetus, Thamnos, I'itoi, Orphan/Chenab). The surviving and disrupted dwarfs are chemically distinct: at fixed mass, the disrupted dwarfs are systematically metal-poor and $α$-enhanced. The disrupted dwarfs define a mass-metallicity relation (MZR) with a similar slope as the $z=0$ MZR followed by the surviving dwarfs, but offset to lower metallicities by $Δ$[Fe/H]$\approx0.3-0.4$ dex. Dwarfs with larger offsets from the $z=0$ MZR are more $α$-enhanced. In simulations as well as observations, galaxies with higher $Δ$[Fe/H] formed at higher redshifts -- exploiting this, we infer the disrupted dwarfs have typical star-formation truncation redshifts of $z_{\rm{trunc}}{\sim}1-2$. We compare the chemically inferred $z_{\rm{trunc}}$ with dynamically inferred accretion redshifts and find almost all dwarfs are quenched only after accretion. The differences between disrupted and surviving dwarfs are likely because the disrupted dwarfs assembled their mass rapidly, at higher redshifts, and within denser dark matter halos that formed closer to the Galaxy. Our results place novel archaeological constraints on low-mass galaxies inaccessible to direct high-$z$ studies: (i) the redshift evolution of the MZR along parallel tracks but offset to lower metallicities extends to $M_{\star}\approx10^{6}-10^{9}M_{\odot}$; (ii) galaxies at $z\approx2-3$ are $α$-enhanced with [$α$/Fe]$\approx0.4$.
During the third Millennium BCE, grey wares were the most popular wares in the Indo-Iranian borderlands inwhich the Bampur Valley and the Sistan basin played a significant role. This research aims to compare grey waresof the above-mentioned regions in order to have a better understanding of possible cultural similarities in bothregions. Similarities between grey wares of the regions at the issue have been frequently explained in the light ofthe long-distance trade mechanism, and considered as a result of the (intentional or unintentional) exchange ofpottery techniques and design styles through commercial activities. Eighteen Grey ceramic sherds were sampledat Tepe Bampur and Shahr-i Sokhta, two key-sites, which are respectively located in the Bampur Valley and theSistan Basin. To compare the raw materials of the ceramic samples after their analyses, some clay samples were alsocollected from two specific natural clay deposits, located 10 km north and 45 km south of Shahr-i Sokhta, and fromthe bank and riverbed of the Bampur River. In addition, a clay sample was also collected from a clay deposit in thePirgel region, located 100 km north of Tepe Bampur and 300 km southwest of Shahr-i Sokhta. By means of XRFtechniques, it was attempted to compare different elements of the ceramic and soil samples. The results show thatthere are close similarities between the chemical elements of the grey wares collected at Shahr-i Sokhta and TepeBampur and soil samples from the Bampur Valley and the Pirgel region. Although these similarities are not seenwith soil samples of the Sistan Basin, the grey wares of these two sites were completely similar. Finally, it can bestated that the fine grey wares of the Sistan Basin were not locally manufactured but were probably imported fromthe Bampur Valley and other regions through long-distance trade during the third millennium BCE.
Kantapon Suraprasit, Rasmi Shoocongdej, Kanoknart Chintakanon
et al.
Abstract The late Pleistocene settlement of highland settings in mainland Southeast Asia by Homo sapiens has challenged our species’s ability to occupy mountainous landscapes that acted as physical barriers to the expansion into lower-latitude Sunda islands during sea-level lowstands. Tham Lod Rockshelter in highland Pang Mapha (northwestern Thailand), dated between 34,000 and 12,000 years ago, has yielded evidence of Hoabinhian lithic assemblages and natural resource use by hunter-gatherer societies. To understand the process of early settlements of highland areas, we measured stable carbon and oxygen isotope compositions of Tham Lod human and faunal tooth enamel. Our assessment of the stable carbon isotope results suggests long-term opportunistic behavior among hunter-gatherers in foraging on a variety of food items in a mosaic environment and/or inhabiting an open forest edge during the terminal Pleistocene. This study reinforces the higher-latitude and -altitude extension of a forest-grassland mosaic ecosystem or savanna corridor (farther north into northwestern Thailand), which facilitated the dispersal of hunter-gatherers across mountainous areas and possibly allowed for consistency in a human subsistence strategy and Hoabinhian technology in the highlands of mainland Southeast Asia over a 20,000-year span near the end of the Pleistocene.
This study presents evidence for the existence of a vast and ancient lake that occupyed a large area of central Iran during the Holocene. The northwestern fringe of the lake, located in the southeast of Tehran, was chosen as the study area. Remains of a Paleo Lake scarp was studied using aerial photographs, Quick Bird satellite imagery, and topographic maps. Furthermore, archeological sites within the region were identified and located, and evidence for the lake was obtained through correlation of these data. Eight shorelines were identified between 1100 – 950 m above sea level, with a depth of 3 – 15 m, and a 43 km in lenght. The results indicated that the active Quaternary faults named North Rey, Kahrizak, and South Rey are in fact the three main topographic levels of the paleo lake and from now on they cannot be considered as the faults. Soil granulation and thin sections showed the presence of non-compacted lake sediments. Results revealed a remarkable association between the location of ancient settlements and altitude of the identified paleo shorelines. All settlements older than 5,000 years were located at 1,000 m. Certainly, the past climate of this region was very different from its contemporary one. Dating studies will provide valuable information about the exact age of the Paleo -Lake and paleo climate changes.
Recent developer funded projects conducted by Archaeology South-East, the contracting division of the Centre for Applied Archaeology (CAA) have, over the last decade or so, begun to fill a void in our knowledge of one of the most archaeologically under-researched areas in Britain. It is becoming clear that rather than being a marginal landscape beyond more habitable zones, the Weald of South-East England was actually one which experienced significant and widespread periods of colonisation. By examining the evidence from a number of sites the author is starting to explore the area’s early medieval landscape, which is beginning to show degrees of continuity from Roman and prehistoric times. This brief update is intended to highlight a revolution in our understanding of South-East England in the centuries surrounding the Roman Conquest. The ongoing research is a case study in landscape analysis and landscape regression. Results will be discussed in forthcoming articles as well as a ‘Spoilheap monograph’ due for release this year (Margetts 2018).
Maria Ivanova, Bea De Cupere, Jonathan Ethier
et al.
The Old World farming system arose in the semi-arid Mediterranean environments of southwest Asia. Pioneer farmers settling the interior of the Balkans by the early sixth millennium BC were among the first to introduce southwest Asian-style cultivation and herding into areas with increasingly continental temperate conditions. Previous research has shown that the bioarchaeological assemblages from early farming sites in southeast Europe vary in their proportions of plant and animal taxa, but the relationship between taxonomic variation and climate has remained poorly understood. To uncover associations between multiple species and environmental factors simultaneously, we explored a dataset including altitude, five bioclimatic and 30 bioarchaeological variables (plant and animal taxa) for 57 of the earliest farming sites in southeast Europe using Canonical Correspondence Analysis (CCA). An extension of correspondence analysis, CCA is widely used in applied ecology to answer similar questions of species-environment relationships, but has not been previously applied in prehistoric archaeology to explore taxonomic and climatic variables in conjunction. The analyses reveal that the changes in plant and animal exploitation which occurred with the northward dispersal of farmers, crops and livestock correlate with south-north climate gradients, and emphasize the importance of adaptations in the animal domain for the initial establishment of farming beyond the Mediterranean areas.
Babak Shaikh Baikloo Islam, Ahmad Chaychi Amirkhiz, Hamidreza Valipour
Prehistoric archaeological sites in the center of the Iranian Plateau suddenly disappeared around the end of the 4th millennium BCE. At Tepe Sialk, near Kashan, the last cultural period, namely Sialk IV - probably established around 3400 BCE after the last settlements of Sialk III6-7b - was abandoned approximately after 500 years. The material culture of this period, known as Proto-Elamite period, is very different from the previous one, showing similarities with Susa III. This period belongs to the same horizon of Uruk III in Mesopotamia and similar evidences were discovered also at sites such as Sofalin, Shoghali, Pardis, Chaltasian, Meymanat Abad, Gholi Darvish, Maral Tepe (Uzbeki), Ghabristan, Arisman and Hissar. With the abandonment of Sialk IV, cultures affected by Uruk in Near East were simultaneously abandoned. This trend of abandonment documented in the center of the Iranian Plateau continued for about 500-1500 years. Palaeo-climatological studies show that this period coincides with a cold and dry period dated approximately between 3200 and 2700 BCE. Apparently, these climate fluctuations threatened life more at the center of the Iranian Plateau than in Mesopotamia and Khuzestan, by virtue of the presence of overflowing and permanent rivers in these territories (Euphrates and Tigris above all), probably forcing the migration of people from the center of the Iranian plateau to more favourable areas. The present comparative study suggests that climate changes were the main reason for the cultural collapse attested in the region.
Kareem El-Badry, Andrew R. Wetzel, Marla Geha
et al.
We examine the effects of stellar feedback and bursty star formation on low-mass galaxies ($M_{\rm star}=2\times10^6-5\times10^{10}{\rm M_{\odot}}$) using the FIRE (Feedback in Realistic Environments) simulations. While previous studies emphasized the impact of feedback on dark matter profiles, we investigate the impact on the stellar component: kinematics, radial migration, size evolution, and population gradients. Feedback-driven outflows/inflows drive significant radial stellar migration over both short and long timescales via two processes: (1) outflowing/infalling gas can remain star-forming, producing young stars that migrate $\sim1{\rm\,kpc}$ within their first $100 {\rm\,Myr}$, and (2) gas outflows/inflows drive strong fluctuations in the global potential, transferring energy to all stars. These processes produce several dramatic effects. First, galaxies' effective radii can fluctuate by factors of $>2$ over $\sim200 {\rm\,Myr}$, and these rapid size fluctuations can account for much of the observed scatter in radius at fixed $M_{\rm star}.$ Second, the cumulative effects of many outflow/infall episodes steadily heat stellar orbits, causing old stars to migrate outward most strongly. This age-dependent radial migration mixes---and even inverts---intrinsic age and metallicity gradients. Thus, the galactic-archaeology approach of calculating radial star-formation histories from stellar populations at $z=0$ can be severely biased. These effects are strongest at $M_{\rm star}\approx10^{7-9.6}{\rm M_{\odot}}$, the same regime where feedback most efficiently cores galaxies. Thus, detailed measurements of stellar kinematics in low-mass galaxies can strongly constrain feedback models and test baryonic solutions to small-scale problems in $Λ$CDM.
A. P. Huxor, A. D. Mackey, A. M. N. Ferguson
et al.
We report the discovery of 59 globular clusters (GCs) and two candidate GCs in a search of the halo of M31, primarily via visual inspection of CHFT/MegaCam imagery from the Pan-Andromeda Archaeological Survey (PAndAS). The superior quality of these data also allow us to check the classification of remote objects in the Revised Bologna Catalogue (RBC), plus a subset of GC candidates drawn from SDSS imaging. We identify three additional new GCs from the RBC, and confirm the GC nature of 11 SDSS objects (8 of which appear independently in our remote halo catalogue); the remaining 188 candidates across both lists are either foreground stars or background galaxies. Our new catalogue represents the first uniform census of GCs across the M31 halo - we find clusters to the limit of the PAndAS survey area at projected radii of up to R_proj ~ 150 kpc. Tests using artificial clusters reveal that detection incompleteness cuts in at luminosities below M_V = -6.0; our 50% completeness limit is M_V ~ -4.1. We construct a uniform set of PAndAS photometric measurements for all known GCs outside R_proj = 25$ kpc, and any new GCs within this radius. With these data we update results from Huxor et al. (2011), investigating the luminosity function (LF), colours and effective radii of M31 GCs with a particular focus on the remote halo. We find that the GCLF is clearly bimodal in the outer halo (R_proj > 30 kpc), with the secondary peak at M_V ~ -5.5. We argue that the GCs in this peak have most likely been accreted along with their host dwarf galaxies. Notwithstanding, we also find, as in previous surveys, a substantial number of GCs with above-average luminosity in the outer M31 halo - a population with no clear counterpart in the Milky Way.
La torre Bombarda es un elemento patrimonial declarado BIC situado en la Serra Gelada, junto al faro de l’Albir, en el municipio de l’Alfàs del Pi. Durante los meses de noviembre de 2011 a enero de 2012 el Ayuntamiento ha ejecutado un proyecto de excavación y consolidación de la torre, con el fin de detener el proceso de degradación al que se estaba viendo sometida. Dicha actuación ha proporcionado datos suficientes para conocer su planta, así como para plantear una propuesta de alzado a partir de la documentación fotogramétrica y reconstrucción 3D de la estructura.