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In response to Timothy Darvill's article, ‘Mythical rings?’ (this issue), which argues for an alternative interpretation of Waun Mawn circle and its relationship with Stonehenge, Parker Pearson and colleagues report new evidence from the Welsh site and elaborate on aspects of their original argument. The discovery of a hearth at the centre of the circle, as well as further features around its circumference, reinforces the authors’ original interpretation. The authors explore the evidence for the construction sequence, which was abandoned before the completion of the monument. Contesting Darvill's argument that the Aubrey Holes at Stonehenge originally held posts, the authors reassert their interpretation of this circle of cut features as Bluestone settings.

Background: In recent years, a relationship between the tumor microenvironment (TME) and patient response to targeted cancer immunotherapy has been suggested. We applied machine-learning algorithms on H&E stained tissue to study the TME in metastatic non-small cell lung cancer (NSCLC) patients. Our goal was to identify digital pathology (DP) features associated with outcome under combination treatment or monotherapy with atezolizumab (atezo), an anti-PD-L1 therapy, and relate those features to other data modalities. We analyzed patient data from two phase 3 clinical trials, OAK (docetaxel versus atezo in 2L+ NSCLC) and IMpower150 (bevacizumab, carboplatin, and paclitaxel (BCP) versus BCP+atezo (ABCP) in advanced 1L non-squamous NSCLC). Methods: As part of our effort to build a DP-based tumor-immune microenvironment atlas, digitized H&E images were registered onto the PathAI research platform. Over 200K annotations from 90 pathologists were used to train convolutional neural networks (CNNs) that classify slide-level human-interpretable features (HIFs) of cells and tissue structures from images and deployed on images from OAK and IMpower150. HIFs and PD-L1 status were associated with outcome in all samples in each arm in OAK and results were validated in IMpower150, using Cox proportional hazard models. Bulk RNAseq was run using samples extracted from the same area as the H&E slide. Results: We identified a composite feature capturing the ratio of immune cells to fibroblasts in the stroma predictive of both overall survival (OS) (HR=0.74 p=0.0046) and progression-free survival (PFS) (HR=0.87 p=0.14). While patients primarily benefit from atezo if they are PD-L1 high, we found that even PD-L1 negative patients benefited from atezo when enriched for this feature (22C3 PD-L1 assay: OS HR=0.59 p=0.015, PFS HR=0.8 p=0.25; SP142 PD-L1 assay: OS HR=0.74 p=0.12, PFS HR=0.88 p=0.45). We thus recognized a DP feature that was predictive for positive outcome with atezo treatment, independent of PD-L1 levels. This association was then validated in IMpower150 comparing ABCP to BCP, both overall (OS HR=0.69 p=0.012) and in PD-L1 negative patients (SP263 assay OS HR=0.56 p=0.034). Integrating with RNAseq, patients enriched for this DP feature showed similar enrichment for B and T gene signatures and depletion in CAF-related gene signatures, thus showing the harmonization of TME between different data modalities. Conclusions: Using a deep learning-based assay for quantifying pathology features of the TME from H&E images in two NSCLC trials, we identified a novel biomarker predictive of outcome to PD-L1 targeting therapy, even in PD-L1 low & negative patients. Importantly, our work shows how different data modalities (DP, gene expression) can be integrated to further our understanding of the TME. Citation Format: Aditi Qamra, Minu K. Srivastava, Eloisa Fuentes, Ben Trotter, Raymond Biju, Guillaume Chhor, James Cowan, Steven Gendreau, Webster Lincoln, Lisa McGinnis, Luciana Molinero, Namrata S. Patil, Amber Schedlbauer, Katja Schulze, Adam Stanford-Moore, Laura Chambre, Ilan Wapinski, David S. Shames, Hartmut Koeppen, Stephanie Hennek, Jane Fridlyand, Jennifer M. Giltnane, Assaf Amitai. Digital pathology based prognostic & predictive biomarkers in metastatic non-small cell lung cancer. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5705.

BackgroundAn accurate histological characterization of immune cells in the tumor microenvironment is essential for developing novel immune oncology targeted therapies and can assist in guiding patient treatment decisions. However, immune phenotyping is subject to challenges of manual scoring and inter-pathologist scoring variability. To support pathologist-scored immune phenotyping across tumor types, we are developing machine learning (ML)-based models that can identify and quantify CD8+ lymphocytes within the stromal and parenchyma regions of tumors from non-small cell lung cancer, renal cell carcinoma, breast cancer, gastric cancer, head and neck squamous cell carcinoma, urothelial carcinoma, and melanoma. Here, we focus on the ML model for melanoma showing recent results for ML-based identification and quantification of CD8+ lymphocytes and concordance with manual pathologic assessment in data derived from clinical trials.MethodsML algorithms were developed to quantify CD8+ lymphocytes in melanoma using 200 samples from a commercial dataset containing both primary and metastatic melanoma cases. Models were trained using the PathAI research platform on digitized whole slide images (WSI) stained for CD8 using clone C8/144b (Dako), and annotations were provided by the PathAI network of expert pathologists. Training included identification of slide artifacts, parenchyma, cancer stroma, and necrosis, as well as CD8+ lymphocytes and other CD8– cell types. Examples of melanin, such as pigmented macrophages, were added to non-CD8+ cell types. To evaluate the performance of the ML model, model-predicted CD8+ counts were compared to a consensus count from five independent pathologists for representative regions (“frames”) using the Pearson correlation. This was done in 112 held-out test frames from 90 WSI baseline samples from three clinical trials of immunotherapy treatment in individuals with metastatic melanoma. Inter-pathologist agreement among the five pathologists was also calculated.ResultsML-based quantitation of CD8 positivity in lymphocytes showed high concordance with manual pathologist consensus counts. In frames validation of CD8+ counts on the test set of WSI, there was high correlation between the ML model and pathologist consensus counts (r=0.92 [95% CI 0.88–0.94]). This correlation was comparable to the agreement among the five expert pathologists (r=0.88 [95% CI 0.85–0.91]).ConclusionsML model-predicted CD8+ cell counts are highly concordant with pathologist scores on WSI samples from melanoma-focused clinical trials. These data demonstrate the capability of AI-powered digital pathology for accurate and reproducible quantitation of CD8+ lymphocytes in clinical trial samples, contributing to improved evaluation of the tumor microenvironment and targeted development of therapeutics.

Geologists and archaeologists have long known that the bluestones of Stonehenge came from the Preseli Hills of west Wales, 230km away, but only recently have some of their exact geological sources been identified. Two of these quarries—Carn Goedog and Craig Rhos-y-felin—have now been excavated to reveal evidence of megalith quarrying around 3000 BC—the same period as the first stage of the construction of Stonehenge. The authors present evidence for the extraction of the stone pillars and consider how they were transported, including the possibility that they were erected in a temporary monument close to the quarries, before completing their journey to Stonehenge.

The discovery of a dismantled stone circle—close to Stonehenge's bluestone quarries in west Wales—raises the possibility that a 900-year-old legend about Stonehenge being built from an earlier stone circle contains a grain of truth. Radiocarbon and OSL dating of Waun Mawn indicate construction c. 3000 BC, shortly before the initial construction of Stonehenge. The identical diameters of Waun Mawn and the enclosing ditch of Stonehenge, and their orientations on the midsummer solstice sunrise, suggest that at least part of the Waun Mawn circle was brought from west Wales to Salisbury Plain. This interpretation complements recent isotope work that supports a hypothesis of migration of both people and animals from Wales to Stonehenge.

Introduction TGFβ is an immunoregulatory cytokine that can function as an oncogenic factor to mediate tumorigenesis, metastasis, and immune escape. Recent studies have shown that TGFβ can drive immune-excluded phenotype in tumor microenvironment (TME) by restricting CD8+ T cell infiltration; thus, tumors with an immune-excluded phenotype or high TGFβ levels may be particularly responsive to TGFβ blockade. Here we combine analysis of intra-tumoral and peripheral TGFβ levels with digital pathology-based immune-phenotyping, which might serve as an integrated approach to identify patients most likely to benefit from TGFβ blockade. Methods About 200 NSCLC FFPE tumor blocks with matching fresh frozen tumor and plasma were purchased from commercial sources. Quantitation of peripheral and intra-tumoral TGFβ (TGFβ1/2/3) levels was performed using a qualified assay for active and total forms. FFPE slides were stained for CD8+ T cells (SP57, Ventana) and scanned at 40x using the Aperio AT2 scanner by Covance. Machine learning (ML) models were developed using the digitized whole slide images to identify CD8+, CD8-, and non-lymphocytes, as well as cancer epithelium, cancer-associated stroma, and artifacts. Data-driven cutoffs were applied to model-generated human-interpretable features (HIFs) of CD8+ lymphocyte density to classify samples as desert, excluded, or inflamed. As an orthogonal approach to the CD8+ density-based cutoff method, all tissue and cell model predictions were used to train a graph neural network (GNN) to classify immune phenotypes. Results We found that TGFβ1 was the predominant isoform detected within the periphery while TGFβ1 and TGFβ2 were measurable in majority of tumor samples; TGFβ3 level was below the detection limit in most samples. Correlation analysis of TGFβ1 expression in plasma and tumor shows poor concordance in the matched samples, which could be due to the relatively lower level of intra-tumoral TGFβ and tumor heterogeneity. This discordance may explain why it is challenging to use plasma TGFβ to predict tumor TGFβ level. ML model quantification of CD8+, CD8-, and non-lymphocytes showed high concordance with the consensus score of 5 independent pathologists on a test set of held-out samples not used in training. This concordance was comparable to that of individual annotators to consensus. Immune-phenotyping results using both cutoff and GNN methods also showed moderate concordance with 5-way pathologist consensus. Conclusions We coupled a ligand binding assay for assessing TGFβ isoforms in both plasma and TME with an ML-powered digital pathology platform that can provide a standardized, scalable, and reproducible method to characterize cancer-immune phenotypes in TME. This integrative approach might identify potential biomarkers to select NSCLC patients that may benefit from TGFβ blockade. Citation Format: Robert Pomponio, Carrie Hendricks, Sarah Mitchell Bean, Hong Wang, Sergine Brutus, Charles Biddle-Snead, Archit Khosla, Adam Stanford-Moore, Cyrus Hedvat, Qi Tang, Roger Trullo, Brigitte Demers, Rui Wang. Quantification of TGFβ protein levels and digital pathology-based immune phenotyping reveal biomarkers for TGF-β blockade therapy patient selection in NSCLC [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5099.

The Complete Calibration of the Color-Redshift Relation (C3R2) survey is a multi-institution, multi-instrument survey that aims to map the empirical relation of galaxy color to redshift to i~24.5 (AB), thereby providing a firm foundation for weak lensing cosmology with the Stage IV dark energy missions Euclid and WFIRST. Here we present 3171 new spectroscopic redshifts obtained in the 2016B and 2017A semesters with a combination of DEIMOS, LRIS, and MOSFIRE on the Keck telescopes. The observations come from all of the Keck partners: Caltech, NASA, the University of Hawaii, and the University of California. Combined with the 1283 redshifts published in DR1, the C3R2 survey has now obtained and published 4454 high quality galaxy redshifts. We discuss updates to the survey design and provide a catalog of photometric and spectroscopic data. Initial tests of the calibration method performance are given, indicating that the sample, once completed and combined with extensive data collected by other spectroscopic surveys, should allow us to meet the cosmology requirements for Euclid, and make significant headway toward solving the problem for WFIRST. We use the full spectroscopic sample to demonstrate that galaxy brightness is weakly correlated with redshift once a galaxy is localized in the Euclid or WFIRST color space, with potentially important implications for the spectroscopy needed to calibrate redshifts for faint WFIRST and LSST sources., Comment: ApJ accepted. Survey website with links to the C3R2 redshift catalog and spectroscopic data hosted by KOA can be found at https://sites.google.com/view/c3r2-survey/home

Age is a fundamental parameter of stars, yet in many cases ages of individual stars are presented without robust estimates of the uncertainty. We have developed a Bayesian framework, BAFFLES, to produce the age posterior for a star from its calcium emission strength (log($R'_{HK}$)) or lithium abundance (Li EW) and $B-V$ color. We empirically determine the likelihood functions for calcium and lithium as functions of age from literature measurements of stars in benchmark clusters with well-determined ages. We use a uniform prior on age which reflects a uniform star formation rate. The age posteriors we derive for several test cases are consistent with literature ages found from other methods. BAFFLES represents a robust method to determine the age posterior probability distribution for any field star with $0.45 \leq B-V \leq 0.9$ and a measurement of $R'_{HK}$ and/or $0.35 \leq B-V \leq 1.9$ and measured Li EW. We compile colors, $R'_{HK}$, and Li EW from over 2630 nearby field stars from the literature and present the derived BAFFLES age posterior for each star., Accepted to ApJ, 80 pages, 14 figures, 3 tables

CatWISE is a program to catalog sources selected from combined ${\it WISE}$ and ${\it NEOWISE}$ all-sky survey data at 3.4 and 4.6 $\mu$m (W1 and W2). The CatWISE Preliminary Catalog consists of 900,849,014 sources measured in data collected from 2010 to 2016. This dataset represents four times as many exposures and spans over ten times as large a time baseline as that used for the AllWISE Catalog. CatWISE adapts AllWISE software to measure the sources in coadded images created from six-month subsets of these data, each representing one coverage of the inertial sky, or epoch. The catalog includes the measured motion of sources in 8 epochs over the 6.5 year span of the data. From comparison to ${\it Spitzer}$, the SNR=5 limits in magnitudes in the Vega system are W1=17.67 and W2=16.47, compared to W1=16.96 and W2=16.02 for AllWISE. From comparison to ${\it Gaia}$, CatWISE positions have typical accuracies of 50 mas for stars at W1=10 mag and 275 mas for stars at W1=15.5 mag. Proper motions have typical accuracies of 10 mas yr$^{-1}$ and 30 mas yr$^{-1}$ for stars with these brightnesses, an order of magnitude better than from AllWISE. The catalog is available in the WISE/NEOWISE Enhanced and Contributed Products area of the NASA/IPAC Infrared Science Archive., Comment: 53 pages, 20 figures, 5 tables. Accepted by ApJS

We present a detailed, multi-wavelength study of star formation (SF) and AGN activity in 11 near-infrared (IR) selected, spectroscopically confirmed, massive ($\gtrsim10^{14}\,\rm{M_{\odot}}$) galaxy clusters at $1, Comment: 26 pages, 14 figures, 6 tables with appendix, accepted for publication in the Astrophysical Journal

We present a list of 15 clusters of galaxies, serendipitously detected by the XMM Cluster Survey (XCS), that have a high probability of detection by the Planck satellite. Three of them already appear in the Planck Early Sunyaev-Zel'dovich (ESZ) catalogue. The estimation of the Planck detection probability assumes the flat Lambda cold dark matter (LambdaCDM) cosmology most compatible with 7-year Wilkinson Microwave Anisotropy Probe (WMAP7) data. It takes into account the XCS selection function and Planck sensitivity, as well as the covariance of the cluster X-ray luminosity, temperature, and integrated comptonization parameter, as a function of cluster mass and redshift, determined by the Millennium Gas Simulations. We also characterize the properties of the galaxy clusters in the final data release of the XCS that we expect Planck will have detected by the end of its extended mission. Finally, we briefly discuss possible joint applications of the XCS and Planck data.

We present measurements of the X-ray observables of the intra-cluster medium (ICM), including luminosity $L_X$, ICM mass $M_{ICM}$, emission-weighted mean temperature $T_X$, and integrated pressure $Y_X$, that are derived from XMM-Newton X-ray observations of a Sunyaev-Zel'dovich Effect (SZE) selected sample of 59 galaxy clusters from the South Pole Telescope SPT-SZ survey that span the redshift range of $0.20 < z < 1.5$. We constrain the best-fit power law scaling relations between X-ray observables, redshift, and halo mass. The halo masses are estimated based on previously published SZE observable to mass scaling relations, calibrated using information that includes the halo mass function. Employing SZE-based masses in this sample enables us to constrain these scaling relations for massive galaxy clusters ($M_{500}\geq 3 \times10^{14}$ $M_\odot$) to the highest redshifts where these clusters exist without concern for X-ray selection biases. We find that the mass trends are steeper than self-similarity in all cases, and with $\geq 2.5{\sigma}$ significance in the case of $L_X$ and $M_{ICM}$. The redshift trends are consistent with the self-similar expectation, but the uncertainties remain large. Core-included scaling relations tend to have steeper mass trends for $L_X$. There is no convincing evidence for a redshift-dependent mass trend in any observable. The constraints on the amplitudes of the fitted scaling relations are currently limited by the systematic uncertainties on the SZE-based halo masses, however the redshift and mass trends are limited by the X-ray sample size and the measurement uncertainties of the X-ray observables., Comment: Accepted for publication in ApJ. 29 pages, 11 figures, 5 tables

We present a spectroscopic catalog of (mostly) red galaxies in 24 galaxy clusters in the redshift range 0.17 < z < 0.92 obtained with the LRIS instrument on the Keck I telescope. Here we describe the observations and the galaxy spectra, including the discovery of three cD galaxies with LINER emission spectra, and the spectroscopic discovery of four new galaxy-galaxy lenses in cluster environments., Submitted to ApJS

We present the surface density of luminous active galactic nuclei (AGNs) associated with a uniformly selected galaxy cluster sample identified in the 8.5 deg2 Bootes field of the NOAO Deep Wide-Field Survey. The clusters are distributed over a large range of redshift (0 0.5. The amplitude of this AGN overdensity increases with redshift. Although there are significant differences between the AGN populations probed by each selection technique, the rise in cluster AGN surface density generally increases more steeply than that of field quasars. In particular, X-ray-selected AGNs are at least 3 times more prevalent in clusters at 1 < z < 1.5 compared to clusters at 0.5 < z < 1. This effect is stronger than can be explained by the evolving median richness of our cluster sample. We thus confirm the existence of a Butcher-Oemler-type effect for AGN in galaxy clusters, with the number of AGNs in clusters increasing with redshift.

We present 20 WISE-selected galaxies with bolometric luminosities L_bol > 10^14 L_sun, including five with infrared luminosities L_IR = L(rest 8-1000 micron) > 10^14 L_sun. These "extremely luminous infrared galaxies," or ELIRGs, were discovered using the "W1W2-dropout" selection criteria which requires marginal or non-detections at 3.4 and 4.6 micron (W1 and W2, respectively) but strong detections at 12 and 22 micron in the WISE survey. Their spectral energy distributions are dominated by emission at rest-frame 4-10 micron, suggesting that hot dust with T_d ~ 450K is responsible for the high luminosities. These galaxies are likely powered by highly obscured AGNs, and there is no evidence suggesting these systems are beamed or lensed. We compare this WISE-selected sample with 116 optically selected quasars that reach the same L_bol level, corresponding to the most luminous unobscured quasars in the literature. We find that the rest-frame 5.8 and 7.8 micron luminosities of the WISE-selected ELIRGs can be 30-80% higher than that of the unobscured quasars. The existence of AGNs with L_bol > 10^14 L_sun at z > 3 suggests that these supermassive black holes are born with large mass, or have very rapid mass assembly. For black hole seed masses ~ 10^3 M_sun, either sustained super-Eddington accretion is needed, or the radiative efficiency must be, 17 pages in emulateapj format, including 11 figures and 5 tables. ApJ in press

We study the evolution of two fundamental properties of galaxy clusters: the luminosity function (LF) and the scaling relations between the total galaxy number N (or luminosity) and cluster mass M. Using a sample of 27 clusters (0, Comment: 4 pages, 4 figures. Accepted for publication in ApJL

We present optical and/or near-IR images of 128 ultra steep spectrum (USS) radio sources. Roughly half of the objects are identified in the optical images (R 94% are detected at K 5). The major axes of the identifications in K-band are preferentially oriented along the radio axes, with half of them having compact morphologies. The 22 sources with spectroscopic redshifts and K-band magnitudes follow the K-z relation found from previous radio samples, but with a larger scatter. We argue that this may be due to a dependence of K-magnitude on the radio power, with the highest radio power sources inhabiting the most massive host galaxies. We present a composite K-z diagram of radio-loud and radio-quiet galaxies, selected from the HDF-North and the Hawaii surveys. Out to z ~ 1, the radio-loud galaxies are >~ 2 magnitudes brighter. We argue that this is not due to a contribution from the AGN or emission lines. This difference strongly suggests that radio galaxies pinpoint the most massive systems out to the highest known redshifts, probably due to the mutual correlation of the mass of the galaxy and the radio power on the mass of the central black hole.

Stern et al.(2012) presented a study of WISE selection of AGN in the 2 deg^2 COSMOS field, finding that a simple criterion W1-W2>=0.8 provides a highly reliable and complete AGN sample for W2, Comment: 34 text pages + 13 Figures + 6 Tables. Accepted for Publication in The Astrophysical Journal. Updated with referee's comments. Minor correction to Tables 1, 2 and 3 regarding an incorrect characterization of the reliability and completeness of the KI and KIM AGN selection criteria

We compare the star formation (SF) activity in cluster galaxies to the field from z=0.3-1.5 using $Herschel$ SPIRE 250$��$m imaging. We utilize 274 clusters from the IRAC Shallow Cluster Survey (ISCS) selected as rest-frame near-infrared overdensities over the 9 square degree Bootes field . This analysis allows us to quantify the evolution of SF in clusters over a long redshift baseline without bias against active cluster systems. Using a stacking analysis, we determine the average star formation rates (SFRs) and specific-SFRs (SSFR=SFR/M$_{\star}$) of stellar mass-limited (M>1.3x10$^{10}$ M$_{\odot}$), statistical samples of cluster and field galaxies, probing both the star forming and quiescent populations. We find a clear indication that the average SF in cluster galaxies is evolving more rapidly than in the field, with field SF levels at z>1.2 in the cluster cores (r0.5 Mpc). These general trends in the cluster cores and outskirts are driven by the lower mass galaxies in our sample. Blue cluster galaxies have systematically lower SSFRs than blue field galaxies, but otherwise show no strong differential evolution with respect to the field over our redshift range. This suggests that the cluster environment is both suppressing the star formation in blue galaxies on long time-scales and rapidly transitioning some fraction of blue galaxies to the quiescent galaxy population on short time-scales. We argue that our results are consistent with both strangulation and ram pressure stripping acting in these clusters, with merger activity occurring in the cluster outskirts., 23 pages, 11 figures, 5 tables. Accepted for publication in MNRAS

We have used the Caltech Submillimeter Observatory (CSO) to follow-up a sample of WISE-selected, hyperluminous galaxies, so called W1W2-dropout galaxies. This is a rare (~ 1000 all-sky) population of galaxies at high redshift (peaks at z=2-3), that are faint or undetected by WISE at 3.4 and 4.6 um, yet are clearly detected at 12 and 22 um. The optical spectra of most of these galaxies show significant AGN activity. We observed 14 high-redshift (z > 1.7) W1W2-dropout galaxies with SHARC-II at 350 to 850 um, with 9 detections; and observed 18 with Bolocam at 1.1 mm, with five detections. Warm Spitzer follow-up of 25 targets at 3.6 and 4.5 um, as well as optical spectra of 12 targets are also presented in the paper. Combining WISE data with observations from warm Spitzer and CSO, we constructed their mid-IR to millimeter spectral energy distributions (SEDs). These SEDs have a consistent shape, showing significantly higher mid-IR to submm ratios than other galaxy templates, suggesting a hotter dust temperature. We estimate their dust temperatures to be 60-120 K using a single-temperature model. Their infrared luminosities are well over 10^{13} Lsun. These SEDs are not well fitted with existing galaxy templates, suggesting they are a new population with very high luminosity and hot dust. They are likely among the most luminous galaxies in the Universe. We argue that they are extreme cases of luminous, hot dust-obscured galaxies (DOGs), possibly representing a short evolutionary phase during galaxy merging and evolution. A better understanding of their long-wavelength properties needs ALMA as well as Herschel data., Will be Published on Sep 1, 2012 by ApJ

We report the discovery by the Wide-field Infrared Survey Explorer of the z = 2.452 source WISE J181417.29+341224.9, the first hyperluminous source found in the WISE survey. WISE 1814+3412 is also the prototype for an all-sky sample of ~1000 extremely luminous "W1W2-dropouts" (sources faint or undetected by WISE at 3.4 and 4.6 microns and well detected at 12 or 22 microns). The WISE data and a 350 micron detection give a minimum bolometric luminosity of 3.7 x 10^13 Lsun, with ~10^14 Lsun plausible. Followup images reveal four nearby sources: a QSO and two Lyman Break Galaxies (LBGs) at z = 2.45, and an M dwarf star. The brighter LBG dominates the bolometric emission. Gravitational lensing is unlikely given the source locations and their different spectra and colors. The dominant LBG spectrum indicates a star formation rate ~300 Msun/yr, accounting for < 10% of the bolometric luminosity. Strong 22 micron emission relative to 350 microns implies that warm dust contributes significantly to the luminosity, while cooler dust normally associated with starbursts is constrained by an upper limit at 1.1 mm. Radio emission is ~10x above the far-infrared/radio correlation, indicating an active galactic nucleus is present. An obscured AGN combined with starburst and evolved stellar components can account for the observations. If the black hole mass follows the local M_BH-bulge mass relation, the implied Eddington ratio is >~4. WISE 1814+3412 may be a heavily obscured object where the peak AGN activity occurred prior to the peak era of star formation., Published in 2012 August 20 Astrophysical Journal

We present new improved constraints on the Hubble parameter H(z) in the redshift range 0.15 < z < 1.1, obtained from the differential spectroscopic evolution of early-type galaxies as a function of redshift. We extract a large sample of early-type galaxies (\sim11000) from several spectroscopic surveys, spanning almost 8 billion years of cosmic lookback time (0.15 < z < 1.42). We select the most massive, red elliptical galaxies, passively evolving and without signature of ongoing star formation. Those galaxies can be used as standard cosmic chronometers, as firstly proposed by Jimenez & Loeb (2002), whose differential age evolution as a function of cosmic time directly probes H(z). We analyze the 4000 �� break (D4000) as a function of redshift, use stellar population synthesis models to theoretically calibrate the dependence of the differential age evolution on the differential D4000, and estimate the Hubble parameter taking into account both statistical and systematical errors. We provide 8 new measurements of H(z) (see Tab. 4), and determine its change in H(z) to a precision of 5-12% mapping homogeneously the redshift range up to z \sim 1.1; for the first time, we place a constraint on H(z) at z \neq 0 with a precision comparable with the one achieved for the Hubble constant (about 5-6% at z \sim 0.2), and covered a redshift range (0.5 < z < 0.8) which is crucial to distinguish many different quintessence cosmologies. These measurements have been tested to best match a ��CDM model, clearly providing a statistically robust indication that the Universe is undergoing an accelerated expansion. This method shows the potentiality to open a new avenue in constrain a variety of alternative cosmologies, especially when future surveys (e.g. Euclid) will open the possibility to extend it up to z \sim 2., 34 pages, 15 figures, 6 tables, published in JCAP. It is a companion to Moresco et al. (2012b, http://arxiv.org/abs/1201.6658) and Jimenez et al. (2012, http://arxiv.org/abs/1201.3608). The H(z) data can be downloaded at http://www.physics-astronomy.unibo.it/en/research/areas/astrophysics/cosmology-with-cosmic-chronometers

This paper presents both the result of a search for fossil systems (FSs) within the XMM Cluster Survey and the Sloan Digital Sky Survey and the results of a study of the stellar mass assembly and stellar populations of their fossil galaxies. In total, 17 groups and clusters are identified at z < 0.25 with large magnitude gaps between the first and fourth brightest galaxies. All the information necessary to classify these systems as fossils is provided. For both groups and clusters, the total and fractional luminosity of the brightest galaxy is positively correlated with the magnitude gap. The brightest galaxies in FSs (called fossil galaxies) have stellar populations and star formation histories which are similar to normal brightest cluster galaxies (BCGs). However, at fixed group/cluster mass, the stellar masses of the fossil galaxies are larger compared to normal BCGs, a fact that holds true over a wide range of group/cluster masses. Moreover, the fossil galaxies are found to contain a significant fraction of the total optical luminosity of the group/cluster within 0.5R200, as much as 85%, compared to the non-fossils, which can have as little as 10%. Our results suggest that FSs formed early and in the highest density regions of the universe and that fossil galaxies represent the end products of galaxy mergers in groups and clusters. The online FS catalog can be found at http://www.astro.ljmu.ac.uk/~xcs/Harrison2012/XCSFSCat.html., 30 pages, 50 figures. ApJ published version, online FS catalog added: http://www.astro.ljmu.ac.uk/~xcs/Harrison2012/XCSFSCat.html

Taking advantage of the impressive sensitivity of Spitzer to detect massive galaxies at high redshift, we study the mid-infrared environments of powerful, high-redshift radio galaxies at 1.2-0.1 (AB), in the fields of 48 radio galaxies at 1.21.2. Using a counts-in-cell analysis, we identify a field as overdense when 15 or more red IRAC sources are found within 1arcmin (i.e.,~0.5Mpc at 1.21.2., Comment: 14 pages, 7 figures, 3 tables, accepted for publication in ApJ

We confirm the detection of 3 groups in the Lynx supercluster, at z~1.3, and give their redshifts and masses. We study the properties of the group galaxies as compared to the central clusters, RXJ0849+4452 and RXJ0848+4453, selecting 89 galaxies in the clusters and 74 galaxies in the groups. We morphologically classify galaxies by visual inspection, noting that our early-type galaxy (ETG) sample would have been contaminated at the 30% -40% level by simple automated classification methods (e.g. based on Sersic index). In luminosity selected samples, both clusters and groups show high fractions of Sa galaxies. The ETG fractions never rise above ~50% in the clusters, which is low compared to the fractions observed in clusters at z~1. However, ETG plus Sa fractions are similar to those observed for ETGs in clusters at z~1. Bulge-dominated galaxies visually classified as Sas might also be ETGs with tidal features or merger remnants. They are mainly red and passive, and span a large range in luminosity. Their star formation seems to have been quenched before experiencing a morphological transformation. Because their fraction is smaller at lower redshifts, they might be the spiral population that evolves into ETGs. For mass-selected samples, the ETG fraction show no significant evolution with respect to local clusters, suggesting that morphological transformations occur at lower masses and densities. The ETG mass-size relation shows evolution towards smaller sizes at higher redshift in both clusters and groups, while the late-type mass-size relation matches that observed locally. The group ETG red sequence shows lower zero points and larger scatters than in clusters, both expected to be an indication of a younger galaxy population. The estimated age difference is small when compared to the difference in age at different galaxy masses., Comment: ApJ, submitted - referee report answered - iterating with the referee

The South Pole Telescope (SPT) is a 10 meter telescope operating at mm wavelengths. It has recently completed a three-band survey covering 2500 sq. degrees. One of the survey's main goals is to detect galaxy clusters using Sunyaev-Zeldovich effect and use these clusters for a variety of cosmological and astrophysical studies such as the dark energy equation of state, the primordial non-gaussianity and the evolution of galaxy populations. Since 2005, we have been engaged in a comprehensive optical and near-infrared followup program (at wavelengths between 0.4 and 5 {\mu}m) to image high-significance SPT clusters, to measure their photometric redshifts, and to estimate the contamination rate of the candidate lists. These clusters are then used for various cosmological and astrophysical studies., Comment: For TAUP 2011 proceedings

We study the relationship between two major baryonic components in galaxy clusters, namely the stars in galaxies, and the ionized gas in the intracluster medium (ICM), using 94 clusters that span the redshift range 0-0.6. Accurately measured total and ICM masses from Chandra observations, and stellar masses derived from the Wide-field Infrared Survey Explorer and the Two-Micron All-Sky Survey allow us to trace the evolution of cluster baryon content in a self-consistent fashion. We find that, within r_{500}, the evolution of the ICM mass--total mass relation is consistent with the expectation of self-similar model, while there is no evidence for redshift evolution in the stellar mass--total mass relation. This suggests that the stellar mass and ICM mass in the inner parts of clusters evolve differently., 5 pages, 4 figures; accepted for publication in ApJ Letters

In 2007, R Coronae Borealis (R CrB) went into an historically deep and long decline. In this state, the dust acts like a natural coronagraph at visible wavelengths, allowing faint nebulosity around the star to be seen. Imaging has been obtained from 0.5 to 500 micron with Gemini/GMOS, HST/WFPC2, Spitzer/MIPS, and Herschel/SPIRE. Several of the structures around R CrB are cometary globules caused by wind from the star streaming past dense blobs. The estimated dust mass of the knots is consistent with their being responsible for the R CrB declines if they form along the line of sight to the star. In addition, there is a large diffuse shell extending up to 4 pc away from the star containing cool 25 K dust that is detected all the way out to 500 micron. The SED of R CrB can be well fit by a 150 AU disk surrounded by a very large diffuse envelope which corresponds to the size of the observed nebulosity. The total masses of the disk and envelope are 10^-4 and 2 M(Sun), respectively, assuming a gas-to-dust ratio of 100. The evidence pointing toward a white-dwarf merger or a final-helium-shell flash origin for R CrB is contradictory. The shell and the cometary knots are consistent with a fossil planetary nebula. Along with the fact that R CrB shows significant Lithium in its atmosphere, this supports the final-helium-shell flash. However, the relatively high inferred mass of R CrB and its high fluorine abundance support a white-dwarf merger., 30 pages, 11 figures, ApJ in press

We forecast the constraints on the values of sigma_8, Omega_m, and cluster scaling relation parameters which we expect to obtain from the XMM Cluster Survey (XCS). We assume a flat Lambda-CDM Universe and perform a Monte Carlo Markov Chain analysis of the evolution of the number density of galaxy clusters that takes into account a detailed simulated selection function. Comparing our current observed number of clusters shows good agreement with predictions. We determine the expected degradation of the constraints as a result of self-calibrating the luminosity-temperature relation (with scatter), including temperature measurement errors, and relying on photometric methods for the estimation of galaxy cluster redshifts. We examine the effects of systematic errors in scaling relation and measurement error assumptions. Using only (T,z) self-calibration, we expect to measure Omega_m to +-0.03 (and Omega_Lambda to the same accuracy assuming flatness), and sigma_8 to +-0.05, also constraining the normalization and slope of the luminosity-temperature relation to +-6 and +-13 per cent (at 1sigma) respectively in the process. Self-calibration fails to jointly constrain the scatter and redshift evolution of the luminosity-temperature relation significantly. Additional archival and/or follow-up data will improve on this. We do not expect measurement errors or imperfect knowledge of their distribution to degrade constraints significantly. Scaling-relation systematics can easily lead to cosmological constraints 2sigma or more away from the fiducial model. Our treatment is the first exact treatment to this level of detail, and introduces a new `smoothed ML' estimate of expected constraints., 28 pages, 17 figures. Revised version, as accepted for publication in MNRAS. High-resolution figures available at http://xcs-home.org (under "Publications")

We present new determinations of the cosmic expansion history from red-envelope galaxies. We have obtained for this purpose high-quality spectra with the Keck-LRIS spectrograph of red-envelope galaxies in 24 galaxy clusters in the redshift range 0.2 < z < 1.0. We complement these Keck spectra with high-quality, publicly available archival spectra from the SPICES and VVDS surveys. We improve over our previous expansion history measurements in Simon et al. (2005) by providing two new determinations of the expansion history: H(z) = 97 +- 62 km/sec/Mpc at z = 0.5 and H(z) = 90 +- 40 km/sec/Mpc at z = 0.8. We discuss the uncertainty in the expansion history determination that arises from uncertainties in the synthetic stellar-population models. We then use these new measurements in concert with cosmic-microwave-background (CMB) measurements to constrain cosmological parameters, with a special emphasis on dark-energy parameters and constraints to the curvature. In particular, we demonstrate the usefulness of direct H(z) measurements by constraining the dark- energy equation of state parameterized by w0 and wa and allowing for arbitrary curvature. Further, we also constrain, using only CMB and H(z) data, the number of relativistic degrees of freedom to be 4 +- 0.5 and their total mass to be < 0.2 eV, both at 1-sigma., Submitted to JCAP

The current consensus is that galaxies begin as small density fluctuations in the early Universe and grow by in situ star formation and hierarchical merging. Stars begin to form relatively quickly in sub-galactic sized building blocks called haloes which are subsequently assembled into galaxies. However, exactly when this assembly takes place is a matter of some debate. Here we report that the stellar masses of brightest cluster galaxies, which are the most luminous objects emitting stellar light, some 9 billion years ago are not significantly different from their stellar masses today. Brightest cluster galaxies are almost fully assembled 4-5 Gyrs after the Big Bang, having grown to more than 90% of their final stellar mass by this time. Our data conflict with the most recent galaxy formation models based on the largest simulations of dark matter halo development. These models predict protracted formation of brightest cluster galaxies over a Hubble time, with only 22% of the stellar mass assembled at the epoch probed by our sample. Our findings suggest a new picture in which brightest cluster galaxies experience an early period of rapid growth rather than prolonged hierarchical assembly., Published in Nature 2nd April 2009. This astro ph version includes main text and supplementary material combined

We have identified 335 galaxy cluster and group candidates, 106 of which are at z > 1, using a 4.5 um selected sample of objects from a 7.25 deg^2 region in the Spitzer Infrared Array Camera (IRAC) Shallow Survey. Clusters were identified as 3-dimensional overdensities using a wavelet algorithm, based on photometric redshift probability distributions derived from IRAC and NOAO Deep Wide-Field Survey data. We estimate only ~10% of the detections are spurious. To date 12 of the z > 1 candidates have been confirmed spectroscopically, at redshifts from 1.06 to 1.41. Velocity dispersions of ~750 km/s for two of these argue for total cluster masses well above 10^14 M_sun, as does the mass estimated from the rest frame near infrared stellar luminosity. Although not selected to contain a red sequence, some evidence for red sequences is present in the spectroscopically confirmed clusters, and brighter galaxies are systematically redder than the mean galaxy color in clusters at all redshifts. The mean I - [3.6] color for cluster galaxies up to z ~ 1 is well matched by a passively evolving model in which stars are formed in a 0.1 Gyr burst starting at redshift z_f = 3. At z > 1, a wider range of formation histories is needed, but higher formation redshifts (i.e. z_f > 3) are favored for most clusters., 56 pages, 19 figures, 3 tables, landscape tables 1 (p. 14) and 2 (p. 29) should be printed separately. Accepted for publication in Astrophysical Journal, updated version will be posted upon publication

We present new spectroscopic observations of the most distant X-ray selected galaxy cluster currently known, XMMXCS J2215.9-1738 at z=1.457, obtained with the DEIMOS instrument at the W. M. Keck Observatory, and the FORS2 instrument on the ESO Very Large Telescope. Within the cluster virial radius, as estimated from the cluster X-ray properties, we increase the number of known spectroscopic cluster members to 17 objects, and calculate the line of sight velocity dispersion of the cluster to be 580+/-140 km/s. We find mild evidence that the velocity distribution of galaxies within the virial radius deviates from a single Gaussian. We show that the properties of J2215.9-1738 are inconsistent with self-similar evolution of local X-ray scaling relations, finding that the cluster is underluminous given its X-ray temperature, and that the intracluster medium contains ~2-3 times the kinetic energy per unit mass of the cluster galaxies. These results can perhaps be explained if the cluster is observed in the aftermath of an off-axis merger. Alternatively, heating of the intracluster medium through supernovae and/or Active Galactic Nuclei activity, as is required to explain the observed slope of the local X-ray luminosity-temperature relation, may be responsible., Comment: 13 pages, 6 figures, accepted for publication in ApJ

We present the results of a comprehensive Spitzer survey of 69 radio galaxies across 160% for ~75% the high redshift radio galaxies. As expected from unified models of AGN, the stellar fraction of the rest-frame H-band luminosity has no correlation with redshift, radio luminosity, or rest-frame mid-IR (5um) luminosity. Additionally, while the stellar H-band luminosity does not vary with stellar fraction, the total H-band luminosity anti-correlates with the stellar fraction as would be expected if the underlying hosts of these radio galaxies comprise a homogeneous population. The resultant stellar luminosities imply stellar masses of 10^{11-11.5}Msun even at the highest redshifts. Powerful radio galaxies tend to lie in a similar region of mid-IR color-color space as unobscured AGN, despite the stellar contribution to their mid-IR SEDs at shorter-wavelengths. The mid-IR luminosities alone classify most HzRGs as LIRGs or ULIRGs with even higher total-IR luminosities. As expected, these exceptionally high mid-IR luminosities are consistent with an obscured, highly-accreting AGN. We find a weak correlation of stellar mass with radio luminosity., Comment: 63 pages, 14 figures, accepted for publication in ApJS

We present high resolution imaging observations of a sample of previously unidentified far-infrared galaxies at z < 0.3. The objects were selected by cross-correlating the IRAS Faint Source Catalog with the VLA FIRST catalog and the HST Guide Star Catalog to allow for adaptive optics observations. We found two new ULIGs (with L_FIR equal to or greater than 10^{12} L_sun) and 19 new LIGs (with L_FIR equal to or greater than 10^{11} L_sun). Twenty of the galaxies in the sample were imaged with either the Lick or Keck adaptive optics systems in H or K'. Galaxy morphologies were determined using the two dimensional fitting program GALFIT and the residuals examined to look for interesting structure. The morphologies reveal that at least 30% are involved in tidal interactions, with 20% being clear mergers. An additional 50% show signs of possible interaction. Line ratios were used to determine powering mechanism; of the 17 objects in the sample showing clear emission lines - four are active galactic nuclei and seven are starburst galaxies. The rest exhibit a combination of both phenomena., 29 pages, 8 figures, accepted for publication in AJ

We explore the near-infrared (NIR) $K$-band properties of galaxies within 93 galaxy clusters and groups using data from the 2MASS. We use X-ray properties of these clusters to pinpoint cluster centers and estimate cluster masses. By stacking all these systems, we study the shape of the cluster luminosity function and the galaxy distribution within the clusters. We find that the galaxy profile is well described by the NFW profile with a concentration parameter c~3, with no evidence for cluster mass dependence of the concentration. Using this sample, whose masses span the range from $3\times10^{13}M_\odot$ to $2\times10^{15}M_\odot$, we confirm the existence of a tight correlation between total galaxy NIR luminosity and cluster binding mass, which indicates that NIR light can serve as a cluster mass indicator. From the observed galaxy profile, together with cluster mass profile measurements from the literature, we find that the \mlr is a weakly decreasing function of cluster radius, and that it increases with cluster mass. We also derive the mean number of galaxies within halos of a given mass. We find that the mean number scales as $N\propto M^{0.84\pm0.04}$ for galaxies brighter than $M_K=-21$, indicating high mass clusters have fewer galaxies per unit mass than low mass clusters. Using published observations at high redshift, we show that higher redshift clusters have higher mean occupation number than nearby systems of the same mass. By comparing the luminosity function & radial distribution of galaxies in low mass and high mass clusters, we show that there is a marked decrease in the number density of galaxies fainter than $M_*$ as one moves to higher mass clusters; in addition, extremely luminous galaxies are more probable in high mass clusters., 17 pages, 11 figures. Accepted for publication in ApJ April 2, 2004

BRIGHTlights,BIGcity:Massivegalaxies,giantLy-anebulae,andproto{clustersWilvanBreugela,MichielReulanda,cWimdeVriesAdamStanfordArjunDeybJaronKurkc,BramVenemansHuubRottgeringGeorgeMileyCarlosDeBreuckdMikeDopitae,RalphSutherlandJossBland{HawthornfaUniversityofCalifornia-LawrenceLivermoreNationalLab oratoryP.O.Box808,MailstopL-413,LivermoreCA94551,U.S.A.bNationalOpticalAstronomyObservatories950N.CherryAve,Tucson,AZ85719cLeidenObservatoryP.O.Box9513,NielsBohrweg2,Leiden2300RA,TheNetherlandsdInst.d'AstrophysiquedeParis98bisBoulevardArago,75014Paris,FranceeAustralianNationalUniversityRes.Scho olofAstronomAz>2)aregreatb eaconsforpinp ointingthemostmassiveob jectsinearlyuniverse,whetherthesearegalaxies,blackholesorevenclustersofgalaxies.Atlowredshiftspowerful,non{thermalradiosourcesareuniqelyasso ciatedwithmassiveellipticals.Theirtwin{jet,double{lob emorphologiesandlargeluminositiessuggestedalreadyearlyonthatsuchgalaxiesmustalsohavespinning,sup er{massivblackholes(SMBH's)intheircenters.1, 2Wenowknothatthemassesofstellarbulgesgalaxiesandtheircentralblackholesarecorrelated,3{5suggestingacausalconnection.IfradiosourcespoweredbySMBH'sthenitisnolongerasurprisethattheirparentgalaxieso ccupytheupp erendofgalaxymassfunction.Thereisexcellentevidencethatradiogalaxiesarealsothemostmassivesystemsathighredshifts,eventhoughtheirparentgalaxiesareveryyoungandmastillbeforming.Thecombinednear{infrared`Hubble'Kzrelationforradioand eldgalaxies6showsthatHzRGsareamongthemostluminoussystemsatanygivenep o chuptoz 5.Between0