Bela Abolfathi
A5023471901- Galaxies: Formation, Evolution, Phenomena
- Gamma-ray bursts and supernovae
- Astronomy and Astrophysical Research
- Astrophysical Phenomena and Observations
- Pulsars and Gravitational Waves Research
- Stellar, planetary, and galactic studies
- Scientific Research and Discoveries
- Big Data Technologies and Applications
- CCD and CMOS Imaging Sensors
- Astrophysics and Cosmic Phenomena
- Parallel Computing and Optimization Techniques
- Advanced Data Storage Technologies
- Gaussian Processes and Bayesian Inference
- Adaptive optics and wavefront sensing
- Nuclear Physics and Applications
- Computational Physics and Python Applications
University of California, Irvine
2017-2023
Abstract We describe the Sloan Digital Sky Survey IV (SDSS-IV), a project encompassing three major spectroscopic programs. The Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) is observing hundreds of thousands Milky Way stars at high resolution and signal-to-noise ratios in near-infrared. Mapping Nearby Galaxies (MaNGA) survey obtaining spatially resolved spectroscopy for nearby galaxies (median <?CDATA $z\sim 0.03$?> ). extended Baryon Oscillation Spectroscopic (eBOSS)...
Abstract The DESI Legacy Imaging Surveys ( http://legacysurvey.org/ ) are a combination of three public projects (the Dark Energy Camera Survey, the Beijing–Arizona Sky and Mayall z -band Survey) that will jointly image ≈14,000 deg 2 extragalactic sky visible from northern hemisphere in optical bands g , r using telescopes at Kitt Peak National Observatory Cerro Tololo Inter-American Observatory. combined survey footprint is split into two contiguous areas by Galactic plane. imaging...
The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since 2014 July. This paper describes second data release from this phase, and 14th SDSS overall (making Data Release Fourteen or DR14). makes taken by SDSS-IV its first two years (2014–2016 July) public. Like all previous releases, DR14 is cumulative, including most recent reductions calibrations phase began operations 2000. New public extended Baryon Oscillation Spectroscopic Survey; Apache Point...
In 2021 May, the Dark Energy Spectroscopic Instrument (DESI) began a 5 yr survey of approximately 50 million total extragalactic and Galactic targets. The primary DESI dark-time targets are emission line galaxies (ELGs), luminous red (LRGs) quasars (QSOs). bright time, will focus on two surveys known as Bright Galaxy Survey (BGS) Milky Way (MWS). also observes selection "secondary" for bespoke science goals. This paper gives an overview publicly available pipeline (desitarget) used to...
Abstract We describe the simulated sky survey underlying second data challenge (DC2) carried out in preparation for analysis of Vera C. Rubin Observatory Legacy Survey Space and Time (LSST) by LSST Dark Energy Science Collaboration (LSST DESC). Significant connections across multiple science domains will be a hallmark LSST; DC2 program represents unique modeling effort that stresses this interconnectivity way has not been attempted before. This encompasses full end-to-end approach: starting...
We carried out spectroscopic monitoring of 21 low-redshift Seyfert 1 galaxies using the Kast double spectrograph on 3-m Shane telescope at Lick Observatory from April 2016 to May 2017. Targeting active galactic nuclei (AGN) with luminosities {\lambda}L{\lambda} (5100 {\AA}) = 10^44 erg/s and predicted H{\beta} lags 20-30 days or black hole masses 10^7-10^8.5 Msun, our campaign probes luminosity-dependent trends in broad-line region (BLR) structure dynamics as well improve calibrations for...
We have modeled the velocity-resolved reverberation response of H\b{eta} broad emission line in nine Seyfert 1 galaxies from Lick Active Galactic Nucleus (AGN) Monitioring Project 2016 sample, drawing inferences on geometry and structure low-ionization broad-line region (BLR) mass central supermassive black hole. Overall, we find that BLR is generally a thick disk viewed at low to moderate inclination angles. combine our sample with prior studies investigate line-profile shape dependence,...
We present the characteristics of Damped Lyman-$\alpha$ (DLA) systems found in data release DR16 extended Baryon Oscillation Spectroscopic Survey (eBOSS) Sloan Digital Sky (SDSS). DLAs were identified using convolutional neural network (CNN) of~\cite{Parks2018}. A total 117,458 absorber candidates with $2 \leq \zdla 5.5$ and $19.7 \lognhi 22$, including 57,136 DLA $\lognhi \geq 20.3$. Mock quasar spectra used to estimate detection efficiency purity resulting catalog. Restricting sample...
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,...
This paper presents the results of Rubin Observatory Dark Energy Science Collaboration (DESC) 3x2pt tomography challenge, which served as a first step toward optimizing tomographic binning strategy for main DESC analysis. The task choosing an optimal scheme photometric survey is made particularly delicate in context metacalibrated lensing catalogue, only photometry from bands included metacalibration process (usually riz and potentially g) can be used sample definition. goal challenge was to...
Abstract We combine our dynamical modeling black-hole mass measurements from the Lick AGN Monitoring Project 2016 sample with measured cross-correlation time lags and line widths to recover individual scale factors, f , used in traditional reverberation-mapping analyses. extend by including prior results Code for Reverberation Modeling of Emission Lines ( caramel ) studies that have utilized methods. Aiming improve precision estimates, as well uncover any regularities behavior broad-line...
In preparation for cosmological analyses of the Vera C. Rubin Observatory Legacy Survey Space and Time (LSST), LSST Dark Energy Science Collaboration (LSST DESC) has created a 300 deg$^2$ simulated survey as part an effort called Data Challenge 2 (DC2). The DC2 sky survey, in six optical bands with observations following reference observing cadence, was processed Pipelines (19.0.0). this Note, we describe public data release resulting object catalogs coadded images five years along...
We combine our dynamical modeling black hole mass measurements from the Lick AGN Monitoring Project 2016 sample with measured cross-correlation time lags and line widths to recover individual scale factors, f, used in traditional reverberation mapping analyses. extend by including prior results Code for Reverberation Modeling of Emission Lines (caramel) studies that have utilized methods. Aiming improve precision estimates, as well uncover any regularities behavior broad-line region (BLR),...