S. Villanueva

THE CARNEGIE SUPERNOVA PROJECT: SECOND PHOTOMETRY DATA RELEASE OF LOW-REDSHIFT TYPE Ia SUPERNOVAE

The Carnegie Supernova Project (CSP) is a five-year survey being carried out at the Las Campanas Observatory to obtain high-quality light curves of ~100 low-redshift Type Ia supernovae (SNe Ia) in a well-defined photometric system. Here we present the first release of photometric data that contains the optical light curves of 35 SNe Ia, and near-infrared light curves for a subset of 25 events. The data comprise 5559 optical (ugriBV) and 1043 near-infrared (Y JHKs ) data points in the natural system of the Swope telescope. Twenty-eight SNe have pre-maximum data, and for 15 of these, the observations begin at least 5 days before B maximum. This is one of the most accurate data sets of low-redshift SNe Ia published to date. When completed, the CSP data set will constitute a fundamental reference for precise determinations of cosmological parameters, and serve as a rich resource for comparison with models of SNe Ia.

Gaia17biu/SN 2017egm in NGC 3191: The Closest Hydrogen-poor Superluminous Supernova to Date Is in a “Normal,” Massive, Metal-rich Spiral Galaxy

Hydrogen-poor superluminous supernovae (SLSNe-I) have been predominantly found in low-metallicity, star-forming dwarf galaxies. Here we identify Gaia17biu/SN 2017egm as an SLSN-I occurring in a nor ...

GMACS: a Wide Field, Multi-Object, Moderate-Resolution, Optical Spectrograph for the Giant Magellan Telescope

We present a conceptual design for a moderate resolution optical spectrograph for the Giant Magellan Telescope (GMT). The spectrograph is designed to make use of the large field-of-view of the GMT and be suitable for observations of very faint objects across a wide range of optical wavelengths. We show some details of the optical and mechanical design of the instrument.

The ultraviolet spectroscopic evolution of the low-luminosity tidal disruption event iPTF16fnl

We present the ultraviolet (UV) spectroscopic evolution of a tidal disruption event (TDE) for the first time. After the discovery of the nearby TDE iPTF16fnl, we obtained a series of observations with the Space Telescope Imaging Spectrograph (STIS) onboard the Hubble Space Telescope (HST). The dominant emission features closely resemble those seen in the UV spectra of the TDE ASASSN-14li and are also similar to those of N-rich quasars. However, there is significant evolution in the shape and central wavelength of the line profiles over the course of our observations, such that at early times the lines are broad and redshifted, while at later times the lines are significantly narrower and peak near the wavelengths of their corresponding atomic transitions. Like ASASSN-14li, but unlike N-rich quasars, iPTF16fnl shows neither MgII

VIRUS Instrument Collimator Assembly

\lambda 2798

KELT-20b: A Giant Planet with a Period of P ∼ 3.5 days Transiting the V ∼ 7.6 Early A Star HD 185603

\AA\ nor CIII]

WASP-167b/KELT-13b: joint discovery of a hot Jupiter transiting a rapidly rotating F1V star

\lambda 1909

The Carnegie Supernova Project. I. Third Photometry Data Release of Low-redshift Type Ia Supernovae and Other White Dwarf Explosions

\AA\ emission features. We also present optical photometry and spectroscopy, which suggest that the complex HeII profiles observed in the optical spectra of many TDEs are in part due to the presence of NIII and CIII Wolf-Rayet features, which can potentially serve as probes of the far-UV when space-based observations are not possible. Finally, we use Swift XRT and UVOT observations to place strong limits on the X-ray emission and determine the characteristic temperature, radius, and luminosity of the emitting material. We find that iPTF16fnl is subluminous and evolves more rapidly than other optically discovered TDEs.

KELT-19Ab: A P ∼ 4.6-day Hot Jupiter Transiting a Likely Am Star with a Distant Stellar Companion

The Visual Integral-Field Replicable Unit Spectrograph (VIRUS) instrument is a baseline array 150 identical fiber fed optical spectrographs designed to support observations for the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX). The collimator subassemblies of the instrument have been assembled in a production line and are now complete. Here we review the design choices and assembly practices used to produce a suite of identical low-cost spectrographs in a timely fashion using primarily unskilled labor.

Continuum Reverberation Mapping of the Accretion Disks in Two Seyfert 1 Galaxies

We report the discovery of KELT-20b, a hot Jupiter transiting a V ~ 7.6 early A star, HD 185603, with an orbital period of P ≃ 3.47 days. Archival and follow-up photometry, Gaia parallax, radial velocities, Doppler tomography, and AO imaging were used to confirm the planetary nature of KELT-20b and characterize the system. From global modeling we infer that KELT-20 is a rapidly rotating (ν sin I* ≃ 120 km s^(-1)) A2V star with an effective temperature of T_(eff) = 8730^(+250)_(-260) K, mass of, M* = ^(+0.14)_(-0.20) M⊙ radius of, R* = 1.561^(+0.058)_(-0.064) R⊙ surface gravity of, log g* = 4.292^(+0.017)_(-0.020), and age of ≾600 Myr. The planetary companion has a radius of R_P = 1.735^(+0.070)_(-0.075) R_J, a semimajor axis of a = 0.0542^(+0.0014)_(-0.0021) au, and a linear ephemeris of BJD_(TDB) = 2457503.120049 ± 0.000190 + E(3.4741070 ± 0.0000019). We place a 3σ upper limit of ~3.5 M_J on the mass of the planet. Doppler tomographic measurements indicate that the planetary orbit normal is well aligned with the projected spin axis of the star (λ = 3.°4± 2.°1). The inclination of the star is constrained to 24.°4 < I* < 155.°6, implying a three-dimensional spin–orbit alignment of 1.°3 < ψ < 69.°8. KELT-20b receives an insolation flux of ~8 x 10^9 erg s^(-1) cm^(-2), implying an equilibrium temperature of of ~2250 K, assuming zero albedo and complete heat redistribution. Due to the high stellar T_(eff), KELT-20b also receives an ultraviolet (wavelength d ⩽ 91.2 nm) insolation flux of ~9.1 x 10^4 erg s^(-1) cm^(-2), possibly indicating significant atmospheric ablation. Together with WASP-33, Kepler-13 A, HAT-P-57, KELT-17, and KELT-9, KELT-20 is the sixth A star host of a transiting giant planet, and the third-brightest host (in V) of a transiting planet.