We measure the tidal alignment of the major axes of luminous red galaxies (LRGs) from the Legacy ... more We measure the tidal alignment of the major axes of luminous red galaxies (LRGs) from the Legacy Imaging Survey and use it to infer the artificial redshift-space distortion signature that will arise from an orientation-dependent, surface-brightness selection in the Dark Energy Spectroscopic Instrument (DESI) survey. Using photometric redshifts to downweight the shape–density correlations due to weak lensing, we measure the intrinsic tidal alignment of LRGs. Separately, we estimate the net polarization of LRG orientations from DESI’s fibre-magnitude target selection to be of order 10−2 along the line of sight. Using these measurements and a linear tidal model, we forecast a 0.5 per cent fractional decrease on the quadrupole of the two-point correlation function for projected separations of 40–80 h−1 Mpc. We also use a halo catalogue from the Abacussummit cosmological simulation suite to reproduce this false quadrupole.
HAL (Le Centre pour la Communication Scientifique Directe), Feb 3, 2023
We report the first results of a high-redshift (z 5) quasar survey using the Dark Energy Spectros... more We report the first results of a high-redshift (z 5) quasar survey using the Dark Energy Spectroscopic Instrument (DESI). As a DESI secondary target program, this survey is designed to carry out a systematic search and investigation of quasars at z 5, up to redshift 6.8. The target selection is based on the DESI Legacy Imaging Surveys (the Legacy Surveys) DR9 photometry, combined with the Pan-STARRS1 data and J-band photometry from public surveys. A first quasar sample has been constructed from the DESI Survey Validation 3 (SV3) and first-year observations until May 2022. This sample includes more than 400 new quasars at redshift 4.7 ≤ z < 6.6, down to 21.5 magnitude in the z band, discovered from 35% of the entire target sample. Remarkably, there are 220 new quasars identified at z ≥ 5, more than one third of existing quasars previously published at this redshift. The observations so far result in an average success rate of 23% at z > 4.7. The current spectral dataset has already allowed analysis of interesting individual objects (e.g., quasars with damped Lyα absorbers and broad absorption line features), and statistical analysis will follow the survey's completion. A set of science projects will be carried out leveraging this program, including quasar luminosity function, quasar clustering, intergalactic medium, quasar spectral properties, intervening absorbers, and properties of early supermassive black holes. Additionally, a sample of 38 new quasars at z ∼ 3.8 − 5.7 discovered from a pilot survey in the DESI SV1 is also published in this paper.
The Robotic Multiobject Focal Plane System of the Dark Energy Spectroscopic Instrument (DESI)
The Astronomical Journal
A system of 5020 robotic fiber positioners was installed in 2019 on the Mayall Telescope, at Kitt... more A system of 5020 robotic fiber positioners was installed in 2019 on the Mayall Telescope, at Kitt Peak National Observatory. The robots automatically retarget their optical fibers every 10–20 minutes, each to a precision of several microns, with a reconfiguration time of fewer than 2 minutes. Over the next 5 yr, they will enable the newly constructed Dark Energy Spectroscopic Instrument (DESI) to measure the spectra of 35 million galaxies and quasars. DESI will produce the largest 3D map of the universe to date and measure the expansion history of the cosmos. In addition to the 5020 robotic positioners and optical fibers, DESI’s Focal Plane System includes six guide cameras, four wave front cameras, 123 fiducial point sources, and a metrology camera mounted at the primary mirror. The system also includes associated structural, thermal, and electrical systems. In all, it contains over 675,000 individual parts. We discuss the design, construction, quality control, and integration of a...
The Millennials: The Importance of Employee Benefits to their Work Life Balance and their Recruitment and Retention in Business Positions
abstract: With the retirement of the Baby Boomer generation, the workforce is getting younger. Mi... more abstract: With the retirement of the Baby Boomer generation, the workforce is getting younger. Millennials will soon make up the majority of the workplace, and it is therefore imperative for organizations to understand the values and work expectations of this emerging generation. This thesis examines the importance of employment benefits towards work life balance and work satisfaction to Millennials, and what employers can do to recruit and retain this generation of workers in the current marketplace. The data for this study was collected by surveying MBA students enrolled at the W.P. Carey School of Business at Arizona State University. A total of sixty-eight students completed the survey, forty-five being Millennials and twenty-three members of Generation X. The data was analyzed using various statistical techniques to assess the generational importance of work life balance and its relationship between particular employee benefits and recruitment and retention at organizations
Master of Arts in Chicana and Chicano Studies This study analyzes the economic challenges and leg... more Master of Arts in Chicana and Chicano Studies This study analyzes the economic challenges and legal issues experienced by Mexicana undocumented renters in the areas of Huntington Park and South Central Los Angeles. This thesis evaluates economic challenges, legal issues, and disparate treatment within code enforcement as it relates to housing conditions for undocumented Mexicana renters. Current literature refers to housing inequalities for poor communities of color, including Latinos/as, however there is an absence of literature focusing on the undocumented Mexicana renter experience. Beginning with the Treaty of Guadalupe Hidalgo and moving into our current housing crisis, this study found that displacement and disparate treatment continues to exist within the undocumented Mexicana renter's experience.
Background: Effective healthcare disparities curricula are essential to improve care of minority ... more Background: Effective healthcare disparities curricula are essential to improve care of minority patients. Methods: A cost-neutral, evidence-based curriculum was created by enhancing established medical school lectures at the UCLA David Geffen School of Medicine class of 2021 (n=188). Lectures within an 8-week course were evaluated for “teachable moments” or broad topics suitable to introduce specific healthcare disparities content. A lecture-enhancing curriculum based on Society of General Internal Medicine learning objectives was introduced into the DGSOM learning management system via supplemental PDF documents. Results: A total of 92 of 188 students completed curricular assessments and were stratified into intervention group (“utilized materials” n=52) and comparison (“did not utilize the material” n=40) groups based on self-reported use of materials. Minorities were more likely to utilize the material (41% of the intervention group vs 17% of the comparison group, p<.01). Pos...
Adapting the mathematical task framework to design online didactic objects
International Journal of Mathematical Education in Science and Technology, 2011
Designing didactic objects involves imagining how students can conceive of specific mathematical ... more Designing didactic objects involves imagining how students can conceive of specific mathematical topics and then imagining what types of classroom discussions could support these mental constructions. This study investigated whether it was possible to design Java ...
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Papers by Nicole Aguilar