A5078149765- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Astronomical Observations and Instrumentation
- Gamma-ray bursts and supernovae
- Astrophysics and Star Formation Studies
- Galaxies: Formation, Evolution, Phenomena
- Computational Physics and Python Applications
- Scientific Research and Discoveries
- Astrophysical Phenomena and Observations
- Pulsars and Gravitational Waves Research
- Solar and Space Plasma Dynamics
- Astrophysics and Cosmic Phenomena
University of California, Santa Cruz
2016-2020
University of California, Los Angeles
2014
PypeIt is a Python package for semi-automated reduction of astronomical, spectroscopic data.Its algorithms build on decades-long development previous data pipelines by the developers (Bernstein et al., 2015;Bochanski 2009).The procedure -including complete list input parameters and available functionality -is provided as online documentation hosted Read Docs, which regularly updated.It set commands designed to perform without any additional coding.In what follows, we provide brief...
We report the discovery of Little Cub, an extremely metal-poor star-forming galaxy in local Universe, found constellation Ursa Major (a.k.a. Great Bear). first identified Cub as a candidate based on its Sloan Digital Sky Survey photometric colors, combined with spectroscopy using Kast spectrograph Shane 3-m telescope at Lick Observatory. In this letter, we present high-quality spectroscopic data taken Low Resolution Imaging Spectrometer Keck Observatory, which confirm nature galaxy. Based...
Abstract We report a method of identifying candidate low-metallicity blue compact dwarf galaxies (BCDs) from the Sloan Digital Sky Survey (SDSS) imaging data, and present 3 m Lick Observatory 10 W.M. Keck optical spectroscopic observations 94 new systems that have been discovered with this method. The BCDs are selected Data Release 12 (DR12) SDSS on basis their photometric colors morphologies. Using Kast spectrometer telescope, we confirm emission-line galaxies, make metallicity estimates...
PypeIt is a Python package for semi-automated reduction of astronomical, spectroscopic data. Its algorithms build on decades-long development previous data pipelines by the developers (Bernstein, Burles, & Prochaska, 2015; Bochanski et al., 2009). The procedure -- including complete list input parameters and available functionality provided as online documentation hosted Read Docs, which regularly updated. (https://pypeit.readthedocs.io/en/latest/). Release v1.0.3 serves following...
ABSTRACT We present radial velocities and chemical abundances for red giant branch stars in the Galactic bulge globular clusters NGC 6342 6366. The are based on measurements of high-resolution ( R ≳ 20,000) spectra obtained with MMT–Hectochelle WIYN–Hydra spectrographs. find that has a heliocentric velocity +112.5 km s −1 σ = 8.6 ), 6366 −122.3 1.5 both have nearly identical metallicities ([Fe/H] ≈ −0.55). shows evidence moderately extended O–Na anti-correlation, but more data needed to...
The Type~Ia supernova (SN~Ia) 2016coj in NGC 4125 (redshift $z=0.004523$) was discovered by the Lick Observatory Supernova Search 4.9 days after fitted first-light time (FFLT; 11.1 before $B$-band maximum). Our first detection (pre-discovery) is merely $0.6\pm0.5$ day FFLT, making SN one of earliest known detections a Ia. A spectrum taken only 3.7 hr discovery (5.0 FFLT) and classified as normal We performed high-quality photometry, low- high-resolution spectroscopy, spectropolarimetry,...
Abstract We present Keck NIRSPEC and NIRES spectroscopy of sixteen metal-poor galaxies that have pre-existing optical observations. The near-infrared (NIR) specifically targets the He i λ 10830 Å emission line, due to its sensitivity physical conditions gas in H ii regions. use these NIR observations, combined with spectroscopy, determine helium abundance across a metallicity range = 7.13–8.00. This data set is two other samples where measurements can be secured: star-forming selected from...
The globular cluster NGC 288 was previously reported to exhibit two distinct red giant branches (RGBs) in the narrowband calcium (HK) and Strömgren b- y-band passes. In order investigate this phenomenon further, we obtained moderate resolution (R ∼ 18,000) spectra of 27 RGB stars with Hydra multifiber spectrograph on Blanco 4 m telescope at Cerro Tololo Inter-American Observatory (CTIO). From these data derive iron (〈[Fe/H]〉 = -1.19; σ 0.12), oxygen (〈[O/Fe]〉 +0.25; 0.13), sodium (〈[Na/Fe]〉...
We report a method of identifying candidate low-metallicity blue compact dwarf galaxies (BCDs) from the Sloan Digital Sky Survey (SDSS) imaging data and present 3-m Lick Observatory 10-m W.M. Keck optical spectroscopic observations 94 new systems that have been discovered with this method. The BCDs are selected Data Release 12 (DR12) SDSS based on their photometric colors morphologies. Using Kast spectrometer telescope, we confirm emission-line make metallicity estimates using empirical R S...