Λ\LambdaCDM not dead yet: massive high-z Balmer break galaxies are less common than previously reported

Early JWST observations that targeted so-called double-break sources (attributed to Lyman and Balmer breaks at $z>7$), reported a previously unknown population of very massive, evolved high-redshift galaxies. This surprising discovery led to a flurry of attempts to explain these objects' unexpected existence including invoking alternatives to the standard $\Lambda$CDM cosmological paradigm. To test these early results, we adopted the same double-break candidate galaxy selection criteria to search for such objects in the JWST images of the CAnadian NIRISS Unbiased Cluster Survey (CANUCS), and found a sample of 19 sources over five independent CANUCS fields that cover a total effective area of $\sim60\,$arcmin$^2$ at $z\sim8$. However, (1) our SED fits do not yield exceptionally high stellar masses for our candidates, while (2) spectroscopy of five of the candidates shows that while all five are at high redshifts, their red colours are due to high-EW emission lines in star-forming galaxies rather than Balmer breaks in massive, evolved systems. Additionally, (3) field-to-field variance leads to differences of $\sim 1.5$ dex in the maximum stellar masses measured in the different fields, suggesting that the early single-field JWST observations may have suffered from cosmic variance and/or sample bias. Finally, (4) we show that the presence of even a single massive outlier can dominate conclusions from small samples such as those in early JWST observations. In conclusion, we find that the double-break sources in CANUCS are not sufficiently massive or numerous to warrant questioning the standard $\Lambda$CDM paradigm.Comment: V2: correction of display problem of Fig.1 in Chrome browser. Submitted to MNRAS, 10 pages (+4 in Appendix), 5 figures (+4), 1 table (+1

Rice Farmer\u27s Risk Attitude: an Analysis of Production Risk in Jawa Barat

IndonesianMakalah ini merupakan, pertama, suatu pendekatan untuk menyelidiki sikap petani terhadap resiko (risk) di Indonesia. Resiko ini secara eksplisit direfleksikan dalam keragaman produksi yang dihasilkan oleh petani. Kedua, tulisan ini mencoba mengevaluasi dampak penggunaan masukan terhadap resiko produksi. Petani-petani contoh dipilih dari enam desa di Daerah Aliran Sungai (DAS) Cimanuk, Jawa Barat. Analisis ini menunjukkan bahwa petani bersifat penghindar resiko (risk-averter) dalam penggunaan pupuk nitrogen dan tenaga kerja manusia. Selanjutnya diperlihatkan bahwa agaknya faktor produksi benih, pupuk nitrogen dan fosfat, serta luas areal berlaku sebagai masukan yang bersifat pembangkit resiko (risk-inducing), sedangkan masukan tenaga kerja (manusia dan ternak) bersifat pengurang resiko (risk-reducing) sebagaimana terlihat pada data musim hujan.EnglishThe paper is aimed, firstly, as a first attempt to investigate farmer\u27s risk attitude in Indonesia. The risk are explicitly assumed reflected in the variability of rice production. Secondly, it evaluates the impact of input USAge on the production risk. The sample farmers were obtained from six desas in the area of the Cimanuk River Basin, Jawa Barat. The analysis suggests that the farmers sample are risk-averter toward nitrogen fertilizer and human labor input. It also appears that seed, nitrogen and phosphorous fertilizer, and land holding indicate as risk-inducing factors of production while the amount of labor (from human or animal) behaves as risk-reducing inputs as shown as rainy season data

Euclid preparation: X. The Euclid photometric-redshift challenge

Forthcoming large photometric surveys for cosmology require precise and accurate photometric redshift (photo-z) measurements for the success of their main science objectives. However, to date, no method has been able to produce photo-zs at the required accuracy using only the broad-band photometry that those surveys will provide. An assessment of the strengths and weaknesses of current methods is a crucial step in the eventual development of an approach to meet this challenge. We report on the performance of 13 photometric redshift code single value redshift estimates and redshift probability distributions (PDZs) on a common set of data, focusing particularly on the 0.2−2.6 redshift range that the Euclid mission will probe. We designed a challenge using emulated Euclid data drawn from three photometric surveys of the COSMOS field. The data was divided into two samples: one calibration sample for which photometry and redshifts were provided to the participants; and the validation sample, containing only the photometry to ensure a blinded test of the methods. Participants were invited to provide a redshift single value estimate and a PDZ for each source in the validation sample, along with a rejection flag that indicates the sources they consider unfit for use in cosmological analyses. The performance of each method was assessed through a set of informative metrics, using cross-matched spectroscopic and highlyaccurate photometric redshifts as the ground truth. We show that the rejection criteria set by participants are efficient in removing strong outliers, that is to say sources for which the photo-z deviates by more than 0.15(1 + z) from the spectroscopic-redshift (spec-z). We also show that, while all methods are able to provide reliable single value estimates, several machine-learning methods do not manage to produce useful PDZs. We find that no machine-learning method provides good results in the regions of galaxy color-space that are sparsely populated by spectroscopic-redshifts, for example z > 1. However they generally perform better than template-fitting methods at low redshift (z < 0.7), indicating that template-fitting methods do not use all of the information contained in the photometry. We introduce metrics that quantify both photo-z precision and completeness of the samples (post-rejection), since both contribute to the final figure of merit of the science goals of the survey (e.g., cosmic shear from Euclid). Template-fitting methods provide the best results in these metrics, but we show that a combination of template-fitting results and machine-learning results with rejection criteria can outperform any individual method. On this basis, we argue that further work in identifying how to best select between machine-learning and template-fitting approaches for each individual galaxy should be pursued as a priority

Persistent luminescence in rare-earth doped nitrido-silicates

Some luminescent materials are able to continue emitting light for hours after they have been excited, a phenomenon known as persistent luminescence. The majority of persistent phosphors known today are based on aluminates or silicates and emit in the blue or green region of the visible spectrum. Orange or red phosphors, strongly desired for emergency signage and medical imaging, are scarce. We prepared the yellowish-orange nitrido-silicates M2Si5N8:Eu,R (M = Ca, Sr, Ba), and their rare-earth codoped variants (R = Nd, Dy, Sm, Tm) through a solid state reaction, and investigated their luminescence and afterglow properties. Persistent luminescence is present in all the prepared samples, but the brightness and duration of the afterglow strongly depend on the host material, the codopant and the choice and ratio of the starting products. This demonstrates the importance of charge carrier traps that are suitably located (both physically and energetically), since these govern the maximum light storage and release capabilities of a persistent phosphor. The number and depth of these traps are estimated from the thermoluminescent glow curve, the integrated light output and the decay profile. Of all the prepared materials, Ca2Si5N8:Eu,Tm is the most promising persistent phosphor with a bright orange afterglow that remains visible for about an hour

The first large catalogue of spectroscopic redshifts in Webb's First Deep Field, SMACS J0723.3−-7327

We present a spectroscopic redshift catalogue of the SMACS J0723.3$-$7327 field ("Webb's First Deep Field") obtained from JWST/NIRISS grism spectroscopy and supplemented with JWST/NIRSpec and VLT/MUSE redshifts. The catalogue contains a total of 190 sources with secure spectroscopic redshifts, including 156 NIRISS grism redshifts, 123 of which are for sources whose redshifts were previously unknown. These new grism redshifts are secured with two or more spectroscopic features (64 sources), or with a single spectral feature whose identity is secured from the object's nine-band photometric redshift (59 sources). These are complemented with 17 NIRSpec and 48 MUSE redshifts, including six new NIRSpec redshifts identified in this work. In addition to the $z_{\rm cl}=0.39$ cluster galaxy redshifts (for which we provide $\sim$40 new NIRISS absorption-line redshifts), we also find three prominent galaxy overdensities at higher redshifts - at $z=1.1$, $z=1.4$, and $z=2.0$ - that were until now not seen in the JWST/NIRSpec and VLT/MUSE data. The paper describes the characteristics of our spectroscopic redshift sample and the methodology we have employed to obtain it. Our redshift catalogue is made available to the community at https://niriss.github.io/smacs0723.Comment: 19 pages, 13 figures, 3 appendices. Accepted for publication in MNRA

La religión púnica en Iberia: lugares de culto

El objetivo que pretendemos en estas páginas es exponer qué yacimientos arqueológicos de la Península Ibérica han sido identificados como santuarios y lugares de culto púnicos, y cuáles son sus características geográficas, sus fases de utilización, los cultos celebrados en ellos, la deidad o deidades adoradas y la contrastación, cuando la hubiere, de la evidencia arqueológica con los testimonios literarios grecolatinos.In this paper, all those archaeological sites located in the Iberian Peninsula that have been interpreted as sanctuaries and cult sites of Punic age are identified and listed. Secondly, their main characteristics such as geographic features, utilisation phases and main deities worshiped are described, with a reference to written testimonies when available