Silence of the Birds:Avifauna exploitation during a period of increasing reliance on domesticates at Late Neolithic Tell Sabi Abyad, Syria

A sample of 219 bird bones, from the Late Neolithic levels at Tell Sabi Abyad, located in the Balikh Valley, Northern Syria, was analysed. These remains informed about the ecological setting of the site, showing it to be permanently occupied, rather than used only seasonally. The practice of fowling at Tell Sabi Abyad was investigated, and both the economic and cultural importance of the birds through time is discussed. The recovery of avifaunal remains from certain phases of occupation, along with their low quantities or absence in others, might reflect changes in subsistence taking place at Tell Sabi Abyad around 6300 BC. This small, but important, sample of bird bones adds to the limited published data available on the avifauna of the Late Neolithic of Northern Syria

A dual geochemical-phytolith methodology for studying activity areas in ephemeral sites: Insights from an ethnographic case study from Jordan.

This study aims to contribute to the interpretation of ephemeral sites by exploring the efficacy of geochemistry and phytolith analysis to identify activity areas in seasonally occupied ethnographic sites. The application of a portable X ray fluorescence (XRF) instrument and phytolith analysis to soil samples from six Bedouin campsites at Wadi Faynan, Jordan, provided insights about anthropogenic enrichment patterns and the effects of short periods of abandonment on these. The compatibility of the two analysis techniques and means to combine the results of both are addressed. The results of this study suggest that soil signatures can be found in ephemeral sites following abandonment, even in dynamic and harsh environments. The efficacy of the geochemical analysis to indicate variance within the data was found to be greater than that of the phytolith analysis in these case studies, while certain trends within the phytolith results were more useful in identifying specific activities. Due to the compatibility of the geochemical and phytolith data, it is proposed that a serial or parallel approach should be taken for their statistical analysis

Out of sight, but not out of mind: exploring how phytolith and geochemical analysis can contribute to understanding social use of space during the Neolithic in the Levant through ethnographic comparison

This research evaluates the potential of a geochemical and phytolith dual methodology for identifying activity areas at ephemeral sites, and adds to our understanding of the formation processes involved in the creation and preservation of soil signatures at ephemeral sites situated in dynamic environments. The work focuses on an investigation of the social use of space in temporary contexts using ethnographic and Neolithic case studies in Jordan. The background to this research involves the need for a better understanding of ancient activities at ephemeral sites during the Neolithic in the Near East. Despite the importance of this period, there are still many unanswered questions regarding the dramatic changes in subsistence and lifestyle that are associated with it. The structures built in this period, which in many ways embody the transition from hunter-gatherer societies to farming communities, are difficult to interpret due to their ephemeral nature and scarcity of organic remains. Nevertheless, although the motivation behind this research is achieving a better understanding of the Neolithic in the Near East, its outcomes are widely applicable to studies of ephemeral archaeological sites in various settings. A dual geochemical and phytolith methodology was applied to seven Bedouin campsites at Wadi Faynan, Jordan, which constituted the ethnoarchaeological data. This was done in order to test the methodology in a controlled setting where knowledge of the use of space at the sites was at hand. The campsites were either occupied or abandoned for various lengths of time during sampling. This allowed for a consideration of taphonomic processes involved in the creation and preservation of soil signatures at these sites. The dual methodology was also applied to three of the Neolithic sites of Wadi el- Jilat, Jordan. This was done in order to test the dual methodology on archaeological case studies, assessing its efficacy in identifying activity areas through the soil signatures that were still available at these sites following an abandonment period of more than 8,000 years. The geochemical and phytolith dual methodology was found to be successful in distinguishing activity areas at the ethnoarchaeological and archaeological sites, and carries much potential for future studies of the use of space in ephemeral structures. While previous studies have experimented with the use of multiple geoarchaeological methods for the study of spatial patterning at ethnographic and archaeological sites, this study is the first to address the use of statistical methods to combine the results from two different analysis techniques. The appropriate use of methods for data display and manipulation was found to be important for the successful application of multiple analysis techniques, allowing their results to aid archaeological interpretations of space. This research has contributed to knowledge by establishing the value of a dual geochemical-phytolith methodology for interpreting the use of space at ephemeral sites. Through future applications of this dual methodology and the statistical tools explored in this study, a contribution can also be made to our understanding of the social use of space in sites and during periods which are difficult to interpret

A model based on Bayesian confirmation and machine learning algorithms to aid archaeological interpretation by integrating incompatible data.

The interpretation of archaeological features often requires a combined methodological approach in order to make the most of the material record, particularly from sites where this may be limited. In practice, this requires the consultation of different sources of information in order to cross validate findings and combat issues of ambiguity and equifinality. However, the application of a multiproxy approach often generates incompatible data, and might therefore still provide ambiguous results. This paper explores the potential of a simple digital framework to increase the explanatory power of multiproxy data by enabling the incorporation of incompatible, ambiguous datasets in a single model. In order to achieve this, Bayesian confirmation was used in combination with decision trees. The results of phytolith and geochemical analyses carried out on soil samples from ephemeral sites in Jordan are used here as a case study. The combination of the two datasets as part of a single model enabled us to refine the initial interpretation of the use of space at the archaeological sites by providing an alternative identification for certain activity areas. The potential applications of this model are much broader, as it can also help researchers in other domains reach an integrated interpretation of analysis results by combining different datasets

An Atmospheric Retrieval of the Brown Dwarf Gliese 229B

© 2022. The Author(s). Published by the American Astronomical Society. This is an open access article distributed under the Creative Commons Attribution License, to view a copy of the license, see: https://creativecommons.org/licenses/by/4.0/We present results from an atmospheric retrieval analysis of Gl 229B using the Brewster retrieval code. We find the best fit model to be cloud-free, consistent with the T dwarf retrieval work of Line et al.; Zalesky et al. and Gonzales et al. Fundamental parameters (mass, radius, log(L Bol /L Sun), log(g)) determined from our model agree within 1σ to SED-derived values, except for T eff where our retrieved T eff is approximately 100 K cooler than the evolutionary model-based SED value. We find a retrieved mass of 50−9+12 M Jup, however, we also find that the observables of Gl 229B can be explained by a cloud-free model with a prior on mass at the dynamical value, 70 M Jup . We are able to constrain abundances for H2O, CO, CH4, NH3, Na and K and find a supersolar C/O ratio as compared to its primary, Gl 229A. We report an overall subsolar metallicity due to atmospheric oxygen depletion, but find a solar [C/H], which matches that of the primary. We find that this work contributes to a growing trend in retrieval-based studies, particularly for brown dwarfs, toward supersolar C/O ratios and discuss the implications of this result on formation mechanisms and internal physical processes, as well as model biases.Peer reviewe

Examining the Rotation Period Distribution of the 40 Myr Tucana-Horologium Association with TESS

The Tucana-Horologium Association (Tuc-Hor) is a 40 Myr old moving group in the southern sky. In this work, we measure the rotation periods of 313 Tuc-Hor objects with TESS light curves derived from TESS full frame images and membership lists driven by Gaia EDR3 kinematics and known youth indicators. We recover a period for 81.4% of the sample and report 255 rotaion periods for Tuc-Hor objects. From these objects we identify 11 candidate binaries based on multiple periodic signals or outlier Gaia DR2 and EDR3 re-normalised unit weight error (RUWE) values. We also identify three new complex rotators (rapidly rotating M dwarf objects with intricate light curve morphology) within our sample. Along with the six previously known complex rotators that belong to Tuc-Hor, we compare their light curve morphology between TESS Cycle 1 and Cycle 3 and find they change substantially. Furthermore, we provide context for the entire Tuc-Hor rotation sample by describing the rotation period distributions alongside other youth indicators such as H{\alpha} and Li equivalent width, as well as near ultra-violet and X ray flux. We find that measuring rotation periods with TESS to be a fast and effective means to confirm members in young moving groups.Comment: 27 pages, 12 figure

The Perkins INfrared Exosatellite Survey (PINES) II. Transit Candidates and Implications for Planet Occurrence around L and T Dwarfs

We describe a new transit detection algorithm designed to detect single transit events in discontinuous Perkins INfrared Exosatellite Survey (PINES) observations of L and T dwarfs. We use this algorithm to search for transits in 131 PINES light curves and identify two transit candidates: 2MASS J18212815+1414010 (2MASS J1821+1414) and 2MASS J08350622+1953050 (2MASS J0835+1953). We disfavor 2MASS J1821+1414 as a genuine transit candidate due to the known variability properties of the source. We cannot rule out the planetary nature of 2MASS J0835+1953's candidate event and perform follow-up observations in an attempt to recover a second transit. A repeat event has yet to be observed, but these observations suggest that target variability is an unlikely cause of the candidate transit. We perform a Markov chain Monte Carlo simulation of the light curve and estimate a planet radius ranging from $4.2^{+3.5}_{-1.6}R_\oplus$ to $5.8^{+4.8}_{-2.1}R_\oplus$, depending on the host's age. Finally, we perform an injection and recovery simulation on our light curve sample. We inject planets into our data using measured M dwarf planet occurrence rates and attempt to recover them using our transit search algorithm. Our detection rates suggest that, assuming M dwarf planet occurrence rates, we should have roughly a 1$\%$ chance of detecting a candidate that could cause the transit depth we observe for 2MASS J0835+1953. If 2MASS J0835+1953 b is confirmed, it would suggest an enhancement in the occurrence of short-period planets around L and T dwarfs in comparison to M dwarfs, which would challenge predictions from planet formation models.Comment: 23 pages, 15 figures, accepted to A

The Perkins INfrared Exosatellite Survey (PINES) I. survey overview, reduction pipeline, and early results

We describe the Perkins INfrared Exosatellite Survey (PINES), a near-infrared photometric search for short-period transiting planets and moons around a sample of 393 spectroscopically confirmed L- and T-type dwarfs. PINES is performed with Boston University’s 1.8 m Perkins Telescope Observatory, located on Anderson Mesa, Arizona. We discuss the observational strategy of the survey, which was designed to optimize the number of expected transit detections, and describe custom automated observing procedures for performing PINES observations. We detail the steps of the PINES Analysis Toolkit (PAT), software that is used to create light curves from PINES images. We assess the impact of second-order extinction due to changing precipitable water vapor on our observations and find that the magnitude of this effect is minimized in Mauna Kea Observatories J band. We demonstrate the validity of PAT through the recovery of a transit of WASP-2 b and known variable brown dwarfs, and use it to identify a new variable L/T transition object: the T2 dwarf WISE J045746.08-020719.2. We report on the measured photometric precision of the survey and use it to estimate our transit-detection sensitivity. We find that for our median brightness targets, assuming contributions from white noise only, we are sensitive to the detection of 2.5 R ⊕ planets and larger. PINES will test whether the increase in sub-Neptune-sized planet occurrence with decreasing host mass continues into the L- and T-dwarf regime.https://iopscience.iop.org/article/10.3847/1538-3881/ac64aa/pdfPublished versio