We present ultraviolet through near-infrared (NIR) broadband photometry, and visual-wavelength and NIR spectroscopy of the Type Iax supernova (SN) 2012Z. The data set consists of both early-and late-time observations, including the first late phase NIR spectrum obtained for a spectroscopically classified SN Iax. Simple model calculations of its bolometric light curve suggest SN 2012Z produced ∼0.3 M of 56 Ni, ejected about a Chandrasekhar mass of material, and had an explosion energy of ∼10 51 erg, making it one of the brightest (M B = −18.3 mag) and most energetic SN Iax yet observed. The late phase (+269d) NIR spectrum of SN 2012Z is found to broadly resemble similar epoch spectra of normal SNe Ia; however, like other SNe Iax, corresponding visual-wavelength spectra differ substantially from all supernova types. Constraints from the distribution of intermediate mass elements, e.g., silicon and magnesium, indicate that the outer ejecta did not experience significant mixing during or after burning, and the late phase NIR line profiles suggests most of the 56 Ni is produced during high density burning. The various observational properties of SN 2012Z are found to be consistent with the theoretical expectations of a Chandrasekhar mass white dwarf progenitor that experiences a pulsational delayed detonation, which produced several tenths of a solar mass of 56 Ni during the deflagration burning phase and little (or no) 56 Ni during the detonation phase. Within this scenario only a moderate amount of Rayleigh-Taylor mixing occurs both during the deflagration and fallback phase of the pulsation, and the layered structure of the intermediate mass elements is a product of the subsequent denotation phase. The fact that the SNe Iax population does not follow a tight brightness-decline relation similar to SNe Ia can then be understood in the framework of variable amounts of mixing during pulsational rebound and variable amounts of 56 Ni production during the early subsonic phase of expansion.

We report evidence for excess blue light from the Type Ia supernova (Sn Ia) SN2012cg at 15 and 16 days before maximum B-band brightness. The emission is consistent with predictions for the impact of the supernova on a nondegenerate binary companion. This is the first evidence for emission from a companion to a normal SNIa. Sixteen days before maximum light, the B V -color of SN2012cg is 0.2 mag bluer than for other normal SNIa. At later times, this supernova has a typical SNIa light curve, with extinction-corrected M 19.62 0.02 B = - mag and m B 0.86 0.02 15 ( ) D =  . Our data set is extensive, with photometry in seven filters from five independent sources. Early spectra also show the effects of blue light, and high-velocity features are observed at early times. Near maximum, the spectra are normal with a silicon velocity v Si =−10,500 km s −1 . Comparing the early data with models by Kasen favors a main-sequence companion of about six solar masses. It is possible that many other SN Ia have main-sequence companions that have eluded detection because the emission from the impact is fleeting and faint.

We present an investigation into the first 500 Myr of galaxy evolution from the Cosmic Evolution Early Release Science (CEERS) survey. CEERS, one of 13 JWST ERS programs, targets galaxy formation from z ∼ 0.5 to >10 using several imaging and spectroscopic modes. We make use of the first epoch of CEERS NIRCam imaging, spanning 35.5 arcmin2, to search for candidate galaxies at z > 9. Following a detailed data reduction process implementing several custom steps to produce high-quality reduced images, we perform multiband photometry across seven NIRCam broad- and medium-band (and six Hubble broadband) filters focusing on robust colors and accurate total fluxes. We measure photometric redshifts and devise a robust set of selection criteria to identify a sample of 26 galaxy candidates at z ∼ 9–16. These objects are compact with a median half-light radius of ∼0.5 kpc. We present an early estimate of the z ∼ 11 rest-frame ultraviolet (UV) luminosity function, finding that the number density of galaxies at M UV ∼ −20 appears to evolve very little from z ∼ 9 to 11. We also find that the abundance (surface density [arcmin−2]) of our candidates exceeds nearly all theoretical predictions. We explore potential implications, including that at z > 10, star formation may be dominated by top-heavy initial mass functions, which would result in an increased ratio of UV light per unit halo mass, though a complete lack of dust attenuation and/or changing star formation physics may also play a role. While spectroscopic confirmation of these sources is urgently required, our results suggest that the deeper views to come with JWST should yield prolific samples of ultrahigh-redshift galaxies with which to further explore these conclusions.

We present a WFC3 F160W (H-band) selected catalog in the CANDELS/GOODS-N field containing photometry from the ultraviolet (UV) to the far-infrared (IR), photometric redshifts and stellar parameters derived from the analysis of the multi-wavelength data. The catalog contains 35,445 sources over the 171 arcmin 2 of the CANDELS F160W mosaic. The 5σ detection limits (within an aperture of radius 0. ′′ 17) of the mosaic range between H = 27.8, 28.2 and 28.7 in the wide, intermediate and deep regions, that span approximately 50%, 15% and 35% of the total area. The multi-wavelength photometry includes broad-band data from UV (U band from KPNO and LBC), optical (HST/ACS F435W, F606W, F775W, F814W, and F850LP), near-to-mid IR (HST/WFC3 F105W, F125W, F140W and F160W, Subaru/MOIRCS Ks, CFHT/Megacam K, and Spitzer/IRAC 3.6, 4.5, 5.8, 8.0 µm) and far IR (Spitzer/MIPS 24µm, HERSCHEL/PACS 100 and 160µm, SPIRE 250, 350 and 500µm) observations. In addition, the catalog also includes, optical medium-band data (R∼ 50) in 25 consecutive bands, λ = 500 to 950 nm, from the SHARDS survey and WFC3 IR spectroscopic observations with the G102 and G141 grisms (R∼ 210 and 130). The use of higher spectral resolution data to estimate photometric redshifts provides very high, and nearly uniform, precision from z = 0 − 2.5. The comparison to 1,485 good quality spectroscopic redshifts up to z ∼ 3 yields ∆z/(1+z spec )=0.0032 and an outlier fraction of η =4.3%. In addition to the multi-band photometry, we release added-value catalogs with emission line fluxes, stellar masses, dust attenuations, UV-and IR-based star formation rates and rest-frame colors.