Simulated Annealing Determination Of Shear Wave Travel Time

The method of simulated annealing is introduced to obtain relative moveouts between different depths from an iso-offset section. This method has been shown to be more consistent than conventional picks based on peaks, troughs, or zero crossings especially in situations where the signal-to-noise ratio is low or the wavelet is emergent. This method also provides a means of quantifying the relative confidence in each pick over the entire depth of the well. The method has been applied to the data obtained by the ARCO shear wave logging tool and compared favorably with more conventional estimates of shear wave slowness and was shown to be robust, even in areas of weak arrivals.Massachusetts Institute of Technology. Full Waveform Acoustic Logging Consortiu

Men’s learning and wellbeing through community organisations in Western Australia

Report to the Western Australia Department of Education & Trainin

Interpreting the near-infrared spectra of the 'golden standard' Type Ia supernova 2005cf

We present nine near-infrared (NIR) spectra of supernova (SN) 2005cf at epochs from -10 d to +42 d with respect to B-band maximum, complementing the existing excellent data sets available for this prototypical Type Ia SN at other wavelengths. The spectra show a time evolution and spectral features characteristic of normal Type Ia SNe, as illustrated by a comparison with SNe 1999ee, 2002bo and 2003du. The broad-band spectral energy distribution (SED) of SN 2005cf is studied in combined ultraviolet (UV), optical and NIR spectra at five epochs between ~ 8 d before and ~ 10 d after maximum light. We also present synthetic spectra of the hydrodynamic explosion model W7, which reproduce the key properties of SN 2005cf not only at UV-optical as previously reported, but also at NIR wavelengths. From the radiative-transfer calculations we infer that fluorescence is the driving mechanism that shapes the SED of SNe Ia. In particular, the NIR part of the spectrum is almost devoid of absorption features, and instead dominated by fluorescent emission of both iron-group material and intermediate-mass elements at pre-maximum epochs, and pure iron-group material after maximum light. A single P-Cygni feature of Mg II at early epochs and a series of relatively unblended Co II lines at late phases allow us to constrain the regions of the ejecta in which the respective elements are abundant.Comment: 11 pages, 6 figures, accepted for publication in MNRA

Senior men’s learning and wellbeing through community participation in Australia

Report to the National Seniors Productive Ageing Centre

Standardizing kilonovae and their use as standard candles to measure the Hubble constant

The detection of GW170817 is revolutionizing many areas of astrophysics with the joint observation of gravitational waves and electromagnetic emissions. These multimessenger events provide a new approach to determine the Hubble constant, thus, they are a promising candidate for mitigating the tension between measurements of type-Ia supernovae via the local distance ladder and the cosmic microwave background. In addition to the "standard siren"provided by the gravitational-wave measurement, the kilonova itself has characteristics that allow one to improve existing measurements or to perform yet another, independent measurement of the Hubble constant without gravitational-wave information. Here, we employ standardization techniques borrowed from the type-Ia community and apply them to kilonovae, not using any information from the gravitational-wave signal. We use two versions of this technique, one derived from direct observables measured from the light curve, and the other based on inferred ejecta parameters, e.g., mass, velocity, and composition, for two different models. These lead to Hubble constant measurements of H0=109-35+49 km s-1 Mpc-1 for the measured analysis, and H0=85-17+22 km s-1 Mpc-1 and H0=79-15+23 km s-1 Mpc-1 for the inferred analyses. This measurement has error bars within ∼2 to the gravitational-wave measurements (H0=74-8+16 km s-1 Mpc-1), showing its promise as an independent constraint on H0

Measuring the Hubble constant with a sample of kilonovae

Kilonovae produced by the coalescence of compact binaries with at least one neutron star are promising standard sirens for an independent measurement of the Hubble constant (H0). Through their detection via follow-up of gravitational-wave (GW), short gamma-ray bursts (sGRBs) or optical surveys, a large sample of kilonovae (even without GW data) can be used for H0 contraints. Here, we show measurement of H0 using light curves associated with four sGRBs, assuming these are attributable to kilonovae, combined with GW170817. Including a systematic uncertainty on the models that is as large as the statistical ones, we find H0 ¼ 73:8þ6:3 5:8 km s1 Mpc1 and H0 ¼ 71:2þ3:2 3:1 km s1 Mpc1 for two different kilonova models that are consistent with the local and inverse-distance ladder measurements. For a given model, this measurement is about a factor of 2-3 more precise than the standard-siren measurement for GW170817 using only GWs

Men's sheds in Australia : Learning through community contexts

‘Men’s sheds’ organisations are typically located in shed or workshop-type spaces in community settings that provide opportunities for regular hands-on activity by groups deliberately and mainly comprising men. Men’s sheds in community organisations are shown to be a relatively new, diverse and poorly known set of community-based, grass-roots organisations—found only in Australia. These informal spaces and programs in community settings have grown recently and rapidly in parts of mainly southern Australia with a higher proportion of older men not in paid work. Men’s sheds are typically organised by, and legally constituted through, existing community organisations. They usually provide a woodworking workshop space, tools and equipment and an adjacent social area in a public, shed-type setting. Some include a metalwork area and/or an adjacent garden

The Lantern Vol. 46, No. 1, December 1979

• Visions in Chains • The Bean • Who Can We Watch Tonite? • Night Glider • The Hurricane • Crisp New Paper • Compassion • Loneliness • 301 • Ode to Man • Unsteady Hands • The Beachcomber • The Pounce • Graveyard Shift • Houston Refineries • Haiku • The End of the Game • A Rose • Ode to a Ziffle • To Carson McCullers • In the May Month • Ghostly Chanting • Travel Excerpts • Face in the Crowd • Waiting in an Airport • A Taste of Winter\u27s Embracehttps://digitalcommons.ursinus.edu/lantern/1115/thumbnail.jp

First-Year Spectroscopy for the SDSS-II Supernova Survey

This paper presents spectroscopy of supernovae discovered in the first season of the Sloan Digital Sky Survey-II Supernova Survey. This program searches for and measures multi-band light curves of supernovae in the redshift range z = 0.05 - 0.4, complementing existing surveys at lower and higher redshifts. Our goal is to better characterize the supernova population, with a particular focus on SNe Ia, improving their utility as cosmological distance indicators and as probes of dark energy. Our supernova spectroscopy program features rapid-response observations using telescopes of a range of apertures, and provides confirmation of the supernova and host-galaxy types as well as precise redshifts. We describe here the target identification and prioritization, data reduction, redshift measurement, and classification of 129 SNe Ia, 16 spectroscopically probable SNe Ia, 7 SNe Ib/c, and 11 SNe II from the first season. We also describe our efforts to measure and remove the substantial host galaxy contamination existing in the majority of our SN spectra.Comment: Accepted for publication in The Astronomical Journal(47pages, 9 figures