Amanda J. Bayless

The type IIP supernova 2012aw in m95: Hydrodynamical modeling of the photospheric phase from accurate spectrophotometric monitoring

We present an extensive optical and near-infrared photometric and spectroscopic campaign of the Type IIP supernova SN 2012aw. The data set densely covers the evolution of SN 2012aw shortly after the explosion through the end of the photospheric phase, with two additional photometric observations collected during the nebular phase, to fit the radioactive tail and estimate the Ni mass. Also included in our analysis is the previously published Swift UV data, therefore providing a complete view of the ultraviolet-optical- infrared evolution of the photospheric phase. On the basis of our data set, we estimate all the relevant physical parameters of SN 2012aw with our radiation-hydrodynamics code: envelope mass M ∼ 20 M , progenitor radius R ∼ 3 × 10 cm (∼430 R), explosion energy E ∼ 1.5 foe, and initial Ni mass ∼0.06 M. These mass and radius values are reasonably well supported by independent evolutionary models of the progenitor, and may suggest a progenitor mass higher than the observational limit of 16.5 ± 1.5 M of the Type IIP events.

Bolometric and UV light curves of core-collapse supernovae

The Swift UV-Optical Telescope (UVOT) has been observing core-collapse supernovae (CCSNe) of all subtypes in the UV and optical since 2005. Here we present 50 CCSNe observed with the Swift UVOT, analyzing their UV properties and behavior. Where we have multiple UV detections in all three UV filters (λ {sub c} = 1928-2600 A), we generate early time bolometric light curves, analyze the properties of these light curves and the UV contribution to them, and derive empirical corrections for the UV-flux contribution to optical-IR based bolometric light curves.

EARLY ULTRAVIOLET OBSERVATIONS OF A TYPE IIn SUPERNOVA (2007pk)

We present some of the earliest UV observations of a Type IIn supernova (SN)-SN 2007pk, where UV and optical observations using Swifts Ultra-Violet/Optical Telescope began 3 days after discovery or {approx}5 days after shock breakout. The SN observations commence at approximately maximum light in the UV and u-band filters, suggesting that the UV light curve peaks begin very rapidly after the initial explosion, and subsequently exhibit a linear decay of 0.20, 0.21, 0.16 mag day{sup -1} in the UVOT uvw2, uvm2, uvw1 ({lambda}{sub c} = 1928, 2246, 2600 Angstrom-Sign ) filters. Meanwhile the b- and v-band light curves begin approximately seven days before v-band peak and exhibit a shallow rise followed by a subsequent decay. A series of optical/near-IR spectra taken with the Hobby-Eberly Telescope at days 3-26 after discovery show spectra similar to that of the peculiar Type IIn 1998S. The emission from 2007pk falls below detection {approx}20 days after discovery in the UV and 50 days in the optical, showing no sign of the long duration emission seen in other Type IIn SNe. We examine the physical and spectral characteristics of 2007pk and compare its UV light curve and decay rate with other Type II SNe.

Multiwavelength observations of the Type IIb supernova 2009mg

We present Swift UVOT and XRT observations, and visual wavelength spectroscopy of the Type IIb supernova (SN) 2009mg, discovered in the Sb galaxy ESO 121-G26. The observational properties of SN 2009mg are compared to the prototype Type IIb SNe 1993J and 2008ax, with which we find many similarities. However, minor differences are discernible including SN 2009mg not exhibiting an initial fast decline or u-band upturn as observed in the comparison objects, and its rise to maximum is somewhat slower leading to slightly broader light curves. The late-time temporal index of SN 2009mg, determined from 40 days post-explosion, is consistent with the decay rate of SN 1993J, but inconsistent with the decay of 56 Co. This suggests leakage of -rays out of the ejecta and a stellar mass on the small side of the mass distribution. Our XRT nondetection provides an upper limit on the mass-loss rate of the progenitor of u M < 1.5 × 10 −5 M⊙ yr −1 . Modelling of the SN light curve indicates a kinetic energy of 0.15 +0.02 −0.13×10 51 erg, an ejecta mass of 0.56

The Supernovae Analysis Application (SNAP)

Southwest Research Institute Internal Research program [R8333, R8498]; NASA Astrophysical Data Analysis Program [NNH15ZDA001N-ADAP]

Stabilized dispersive focal plane systems for space

As the costs of space missions continue to rise, the demand for compact, low mass, low-cost technologies that maintain high reliability and facilitate high performance is increasing. One such technology is the stabilized dispersive focal plane system (SDFPS). This technology provides image stabilization while simultaneously delivering spectroscopic or direct imaging functionality using only a single optical path and detector. Typical systems require multiple expensive optical trains and/or detectors, sometimes at the expense of photon throughput. The SDFPS is ideal for performing wide-field low-resolution space-based spectroscopic and direct-imaging surveys. In preparation for a suborbital flight, we have built and ground tested a prototype SDFPS that will concurrently eliminate unwanted image blurring due to the lack of adequate platform stability, while producing images in both spectroscopic and direct-imaging modes. We present the overall design, testing results, and potential scientific applications.

SCORPIO: the Gemini facility instrument for LSST follow-up

We present the current status of the SCORPIO project, the facility instrument for Gemini South designed to perform follow up studies of transients in the LSST era while carrying out with unique efficiency a great variety of astrophysical programs. SCORPIO operates in the wavelength range 385-2350 nanometers, observing simultaneously in the grizYJHK bands. It can be used both in imaging (seeing limited) and spectroscopic (long-slit) mode, and thanks to the use of frame-transfer CCDs it can monitor variable sources with milli-second time-resolution. The project has recently passed PDR and is on schedule to be commissioned at the time of the LSST first light.

Observing modes for the new SCORPIO imager and spectrograph at Gemini South

SCORPIO (Spectrograph and Camera for Observation of Rapid Phenomena in the Infrared and Optical) is the new workhorse instrument for the Gemini South Telescope in Chile. Originally proposed in response to the Gen4#3 solicitation, SCORPIO is a unique fast-multicolor imager and ultra-wide band spectrograph capable of rapid exposures for high time-resolution images and spectra. SCORPIO consists of 8 separate channels (corresponding to the standard wavebands g, r, i, z, Y, H, J, K) that can operate with different exposure times. Each channel can be used in imaging or long-slit mode, with independent readout timing. In this report we illustrate the detectors, the control systems, and the observing modes that will be available with SCORPIO.

Understanding the Death of Massive Stars Using an Astrophysical Transients Observatory

The death of massive stars, manifested as gamma-ray bursts and core-collapse supernovae, critically influence how the universe formed and evolves. Despite their fundamental importance, our understanding of these enigmatic objects is severely limited. We have performed a concept study of an Astrophysical Transient Observatory (ATO) that will rapidly facilitate an expansion of our understanding of these objects. ATO combines a very wide-field X-ray telescope, a near-infrared telescope, a multi-mode ultraviolet instrument, and a rapidly slewing spacecraft to realize two primary goals: (1) characterize the highest-redshift massive stars and their environments, and (2) constrain the poorly understood explosion mechanism of massive stars. The goals are met by observing the first massive stars to explode as gamma-ray bursts and to probe their environments, and by observing the shock breakout of core-collapse supernovae to measure the outer envelope parameters of massive stars. Additionally, ATO will observe the shock breakout of Type Ia supernovae and their shock interaction with a companion, electromagnetic counterparts to gravitational wave sources, kilonovae, tidal disruption events, cataclysmic variables, X-ray transients, flares from exoplanet host stars, and the escape of ionizing radiation from star-forming galaxies. A description of the ATO instruments, the mission simulation, and technology readiness level is provided.