We present the discovery of a new Jovian-sized planet, TOI-3757 b, the lowest-density transiting planet known to orbit an M dwarf (M0V). This planet was discovered around a solar-metallicity M dwarf, using Transiting Exoplanet Survey Satellite photometry and confirmed with precise radial velocities from the Habitable-zone Planet Finder (HPF) and NEID. With a planetary radius of 12.0(-0.5)(+0.4) R-circle plus and mass of 85.3(-8.7)(+8.8)M(circle plus), not only does this object add to the small sample of gas giants (similar to 10) around M dwarfs, but also its low density (rho = 0.27-(+0.05)(0.04) g cm(-3)) provides an opportunity to test theories of planet formation. We present two hypotheses to explain its low density; first, we posit that the low metallicity of its stellar host (similar to 0.3 dex lower than the median metallicity of M dwarfs hosting gas giants) could have played a role in the delayed formation of a solid core massive enough to initiate runaway accretion. Second, using the eccentricity estimate of 0.14 +/- 0.06, we determine it is also plausible for tidal heating to at least partially be responsible for inflating the radius of TOI-3757b b. The low density and large scale height of TOI-3757 b makes it an excellent target for transmission spectroscopy studies of atmospheric escape and composition (transmission spectroscopy measurement of similar to 190). We use HPF to perform transmission spectroscopy of TOI-3757 b using the helium 10830 angstrom line. Doing this, we place an upper limit of 6.9% (with 90% confidence) on the maximum depth of the absorption from the metastable transition of He at similar to 10830 angstrom, which can help constraint the atmospheric mass-loss rate in this energy-limited regime.

Here we detail the on-sky performance of the NEID Port Adapter one year into full science operation at the WIYN 3.5m Telescope at Kitt Peak National Observatory. NEID is an optical (380-930 nm), fiber-fed, precision Doppler radial velocity system developed as part of the NASA-NSF Exoplanet Observational Research (NN-EXPLORE) partnership. The NEID Port Adapter mounts directly to a bent-Cassegrain port on the WIYN Telescope and is responsible for precisely and stably placing target light on the science fibers. Precision acquisition and guiding is a critical component of such extreme precision spectrographs. In this work, we describe key on-sky performance results compared to initial design requirements and error budgets. While the current Port Adapter performance is more than sufficient for the NEID system to achieve and indeed exceed its formal instrumental radial velocity precision requirements, we continue to characterize and further optimize its performance and efficiency. This enables us to obtain better NEID datasets and in some cases, improve the performance of key terms in the error budget needed for future extreme precision spectrographs with the goal of observing ExoEarths, requiring similar to 10 cm/s radial velocity measurements.

Using the CLEO II detector at the Cornell Electron Storage Ring we have measured the ratio of branching fractions, B(D+ --> K-pi+pi+)/B(D0 --> K-pi+ = 2.35 +/- 0.16 +/- 0.16. Our recent measurement of B(D0 --> K-pi+) then gives B(D+ --> K-pi+pi+) = (9.3 +/- 0.6 +/- 0.8)%.

We present new radial velocity (RV) measurements for 11 candidate young very-low-mass stars and brown dwarfs, with spectral types from M7 to L7. Candidate young objects were identified by features indicative of low surface gravity in their optical and/or near-infrared spectra. RV measurements are derived from high-resolution (R = lambda/Delta lambda = 20,000) J-band spectra taken with NIRSPEC at the Keck Observatory. We combine RVs with proper motions and trigonometric distances to calculate three-dimensional space positions and motions and to evaluate membership probabilities for nearby young moving groups (NYMGs). We propose 2MASS J00452143+1634446 (L2 beta, J = 13.06) as an RV standard given the precision and stability of measurements from three different studies. We test the precision and accuracy of our RV measurements as a function of spectral type of the comparison object, finding that RV results are essentially indistinguishable even with differences of +/- 5 spectral subtypes. We also investigate the strengths of gravity-sensitive K I lines at 1.24-1.25 tm and evaluate their consistency with other age indicators. We confirm or reconfirm four brown dwarf members of NYMGs-2MASS J00452143+1634446, WISE J00470038+6803543, 2MASS J011747483403258, and 2MASS J193555952846343-and their previous age estimates. We identify one new brown dwarf member of the Carina-Near moving group, 2M2154-10. The remaining objects do not appear to be members of any known NYMGs, despite their spectral signatures of youth. These results add to the growing number of very-low-mass objects exhibiting signatures of youth that lack likely membership in a known NYMG, thereby compounding the mystery regarding local, low-density star formation.

Density functional theory (DFT) based first-principles calculations using GGA+U method have been performed for the first time to investigate elastic, electronic, optical, thermodynamic properties including charge density, Fermi surface, Mulliken population analysis, and theoretical Vickers hardness of the newly synthesized LiCuBiO4 (LCBO) compound. The calculated structural parameters are in good agreement with available experimental results, which assessed the reliability of our calculations. The analysis of elastic constants indicates mechanical stability of the LCBO. The values of Poisson's and Pugh's ratios confirm the ductile nature of the LCBO. The mechanically anisotropy is found by the different anisotropy factors. The overlapping of valence and conduction bands near the Fermi level (E-F) and the several bands crossing the E-F reveal the metallic behaviour of the LCBO. The electronic charge density mapping and Mulliken population analysis exhibits a combination of covalent, ionic, and metallic bonding of the LCBO. The calculated Fermi surface comprised of two-dimensional topology due to the low-dispersion of O-2p and Cu-3d states, which implies the possible multi-band nature of LCBO. The analysis of thermodynamic and various optical properties suggest that LCBO can be a potential candidate for optoelectronic devices in the visible and ultraviolet energy regions and as a thermal barrier coating (TBC) material. (C) 2019 The Authors. Published by Elsevier B.V.

Atmospheric escape is considered to be one of the main channels for evolution in sub-Jovian planets, particularly in their early lives. While there are several hypotheses proposed to explain escape in exoplanets, testing them with atmospheric observations remains a challenge. In this context, high-resolution transmission spectroscopy of transiting exoplanets for the metastable helium triplet (He 2(3)S) at 1083 nm has emerged as a reliable technique for observing and measuring escape. To aid in the prediction and interpretation of metastable He transmission spectroscopy observations, we developed the code p-winds. This is an open-source, fully documented, scalable Python implementation of the one-dimensional, purely H+He Parker wind model for upper atmospheres coupled with ionization balance, ray-tracing, and radiative transfer routines. We demonstrate an atmospheric retrieval by fitting p-winds models to the observed metastable He transmission spectrum of the warm Neptune HAT-P-11 b and take the variation in the in-transit absorption caused by transit geometry into account. For this planet, our best fit yields a total atmospheric escape rate of approximately 2.5 x 10(10) g s(-1) and an outflow temperature of 7200 K. The range of retrieved mass loss rates increases significantly when we let the H atom fraction be a free parameter, but its posterior distribution remains unconstrained by He observations alone. The stellar host limb darkening does not have a significant impact on the retrieved escape rate or outflow temperature for HAT-P-11 b. Based on the non-detection of escaping He for GJ 436 b, we are able to rule out total escape rates higher than 3.4 x 10(10) g s(-1) at 99.7% (3 sigma) confidence.

A variety of secondary mineralogies has been detected on Mars from both orbiters and landers, indicating widespread aqueous alteration of the crust. Many of these locales exhibit sulfates, which in some cases imply acidic fluids. At present, there are few constraints on the paleoenvironmental conditions that existed during formation of the widespread and diverse classes of secondary minerals on Mars. We investigated hydrothermal systems at three active acidic volcanic systems in Nicaragua, including Cerro Negro, Momotombo, and Telica. The recently erupted materials are similar in composition to the Martian crust and are undergoing extensive acid-sulfate alteration predominately in gas-dominated settings (fumaroles). We characterized the secondary mineralogy and local variables, including temperature, pH, rock and gas composition, and fluid-rock ratio. We find that these environmental parameters exhibit strong controls on the alteration mineralogy. The environments studied include pH that ranged from -1 to 6, temperatures from ambient to hundreds of degrees Celsius, and fumaroles to hot springs. The hottest and most acidic systems contained sulfur, silica, and minor gypsum, while moderately acidic and cooler fumaroles included abundant silica, gypsum and other hydrated sulfates, and phyllosilicates. A setting with a higher fluid-rock ratio but similar temperature and acidity was dominated by phyllosilicates and, to a lesser degree, sulfates. The characterization of aqueous alteration of basalts under a variety of environmental conditions provides a conceptual framework for interpretation of similar relic environments on Mars. Finally, while identification of phyllosilicates on Mars is generally thought to require neutral to alkaline fluids, we documented significant formation of these minerals in the acidic volcanic systems.

To interpret modern-day unrest at Yellowstone Caldera, timescales leading up to its most common type of eruption-effusively emplaced rhyolite-must be quantified. This work takes advantage of the different rates of elemental diffusion in clinopyroxene to calculate the magmatic timescales of events preceding eruption of the ca. 262 ka Scaup Lake rhyolite, which ended similar to 220,000 years of dormancy in this high-silica system. Here, we present diffusion chronometry timescales accounting for various sources of error and using multiple elements from NanoSIMS measurements of clinopyroxene rims. We combine these with previously published timescales from sanidine rims to better understand the relationship between timescales captured by different minerals from the same volcanic event. We show that timescales archived by rims of different types of phenocrysts from the same lava may not be concomitant. The Scaup Lake rhyolite appears to have undergone several rejuvenation events over similar to 5000 years before its eruption, and the last events (<40 years before eruption) were not recorded by clinopyroxene. This work highlights the importance of using multiple methods to determine a timescale for a given process. Although many studies use Fe-Mg zonation from BSE images to calculate diffusive timescales alone, we show that these are maximums or overestimates if not referenced to the appropriate initial condition. Instead, we demonstrate that diffusion chronometry conducted with multiple elements in multiple mineral phases with rigorous error propagation produces the most robust and accurate temporal results. In addition, we recommend that diffusion chronometry results not be interpreted in isolation, but rather in a holistic petrological approach that includes consideration of the relevant phase equilibria and crystal growth and dissolution rates.

We report the results from a deep HST NICMOS H-band imaging survey of a carefully selected sample of 33 luminous, late-stage galactic mergers at z < 0.3. This program is part of QUEST (Quasar/ULIRG Evolutionary Study). Signs of a recent galactic interaction are seen in all of these objects, including all seven IR-excess Palomar-Green (PG) QSOs in the sample. Unsuspected double nuclei are detected in five ULIRGs. A detailed two-dimensional analysis of the surface brightness distributions in these objects indicates that the great majority (81%) of the single-nucleus systems show a prominent early-type morphology. However, low-surface-brightness exponential disks are detected on large scales in at least four of these sources. The hosts of "warm'' ( IRAS 25 to 60 mu m flux ratio f(25)/f(60) > 0: 2), AGN-like systems are of early type and have less pronounced merger-induced morphological anomalies than the hosts of cool systems with LINER or H II region - like nuclear optical spectral types. The host sizes and luminosities of the seven PG QSOs in our sample are statistically indistinguishable from those of the ULIRG hosts. The hosts of ULIRGs and PG QSOs lie close to the locations of intermediate-size (similar to 1L* -2L*) spheroids in the photometric projection of the fundamental plane of ellipticals, although there is a tendency for the ULIRGs with small hosts to be brighter than normal spheroids. The black hole masses derived from the galaxy host luminosities imply sub-Eddington accretion rates for all objects in the sample.

We present a study of the nearby Seyfert galaxyNGC 1068 usingmid- and far- infrared data acquired with the IRAC, IRS, and MIPS instruments aboard the Spitzer Space Telescope. The images show extensive 8 and 24 mu m emission coinciding with star formation in the inner spiral approximately 1500 (1 kpc) from the nucleus and a bright complex of star formation similar to 47" (3 kpc) southwest of the nucleus. The brightest 8 mu m polycyclic aromatic hydrocarbon (PAH) emission regions coincide remarkably well with knots observed in an H alpha image. Strong PAH features at 6.2, 7.7, 8.6, and 11.3 mu m are detected in IRS spectrameasured at numerous locations inside, within, and outside the inner spiral. The IRAC colors and IRS spectra of these regions rule out dust heated by the active galactic nucleus (AGN) as the primary emission source; the spectral energy distributions are dominated by starlight and PAH emission. The equivalent widths and flux ratios of the PAH features in the inner spiral are generally consistent with conditions in a typical spiral galaxy interstellar medium (ISM). Interior to the inner spiral, the influence of the AGN on the ISM is evident via PAH flux ratios indicative of a higher ionization parameter and a significantly smallermean equivalent width than observed in the inner spiral. The brightest 8 and 24 mu m emission peaks in the disk of the galaxy, even at distances beyond the inner spiral, are located within the ionization cones traced by [OIII]/H beta, and they are also remarkably well aligned with the axis of the radio jets. Although it is possible that radiation from the AGN may directly enhance PAH excitation or trigger the formation of OB stars that subsequently excite PAH emission at these locations in the inner spiral, the orientation of collimated radiation from the AGN and star formation knots in the inner spiral could be coincidental. The brightest PAH- and 24 mu m-emitting regions are also located precisely where two spiral arms of molecular gas emerge from the ends of the inner stellar bar; this is consistent with kinematic models that predict maxima in the accumulation and compression of the ISM, where gas gets trapped within the inner Lindblad resonance of a large stellar bar that contains a smaller, weaker bar.