Sarah Tuttle | University of Washington (original) (raw)
Papers by Sarah Tuttle
The Astrophysical Journal
We present the first publicly released catalog of sources obtained from the Hobby-Eberly Telescop... more We present the first publicly released catalog of sources obtained from the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX). HETDEX is an integral field spectroscopic survey designed to measure the Hubble expansion parameter and angular diameter distance at 1.88 < z < 3.52 by using the spatial distribution of more than a million Lyα-emitting galaxies over a total target area of 540 deg2. The catalog comes from contiguous fiber spectra coverage of 25 deg2 of sky from 2017 January through 2020 June, where object detection is performed through two complementary detection methods: one designed to search for line emission and the other a search for continuum emission. The HETDEX public release catalog is dominated by emission-line galaxies and includes 51,863 Lyα-emitting galaxy (LAE) identifications and 123,891 [O ii]-emitting galaxies at z < 0.5. Also included in the catalog are 37,916 stars, 5274 low-redshift (z < 0.5) galaxies without emission lines, and 4976 activ...
Cornell University - arXiv, Jul 10, 2019
One outcome of the 2015 Inclusive Astronomy conference was the establishment of an accessibility/... more One outcome of the 2015 Inclusive Astronomy conference was the establishment of an accessibility/disability advocacy group within professional, US-based astronomy, organized by a coalition of disabled astronomers and allies and is supported by the American Astronomical Society (AAS). While the Working Group on Accessibility and Disability (WGAD 1) has focused on AAS-led initiatives to increase the accessibility of publications, databases, and professional meetings, there is an urgent need to expand these accessibility efforts beyond the professional society and into the wider astronomical community. Our long-term goals include proactively designing learning and working environments to be as accessible as possible, the removal of existing physical, technological, and pedagogical barriers to access, and provision of greater support for the career progress, promotion, and retention of disabled astronomers and educators. Progress toward these goals can be made by establishing and then sustaining a culture of inclusion in which all identities and intersections of identity are equally represented, while recognizing that progress which liberates one identity group may not liberate another in the same way. In the decades since the passage of the Americans with Disabilities Act (ADA), it has become clear that academic departments and research institutions will only undertake the necessary cultural and infrastructure changes if motivated by clear guidelines from funding organizations or ADA non-compliance lawsuits 2 , 3 , 4. In this white paper, we outline the major barriers to access within the educational and professional practice of astronomy. We present current best practices for inclusivity and accessibility, including classroom practices, institutional culture, support for infrastructure creation, hiring processes, and outreach initiatives. We present specific ways-beyond simple compliance with the ADA-that funding agencies, astronomers, and institutions can work together to make astronomy as a field more accessible, inclusive, and equitable. In particular, funding agencies should include the accessibility of institutions during proposal evaluation, hold institutions accountable for inaccessibility, and support efforts to gather data on the status and progress of astronomers and astronomy students with disabilities.
Cornell University - arXiv, Aug 7, 2019
Ground-based and Airborne Instrumentation for Astronomy IX
The Astrophysical Journal
We present the Lyα emission line luminosity function (LF) of the active galactic nuclei (AGN) in ... more We present the Lyα emission line luminosity function (LF) of the active galactic nuclei (AGN) in the first release of the Hobby–Eberly Telescope Dark Energy Experiment Survey (HETDEX) AGN catalog. The AGN are selected either by emission line pairs characteristic of AGN or by a single broad emission line, free of any photometric preselections (magnitude/color/morphology). The sample consists of 2346 AGN spanning 1.88 < z < 3.53, covering an effective area of 30.61 deg2. Approximately 2.6% of the HETDEX AGN are not detected at >5σ confidence at r ∼ 26 in the deepest r-band images we have searched. The Lyα line luminosity ranges from ∼1042.3 to 1045.9 erg s−1. Our Lyα LF shows a turnover luminosity with opposite slopes on the bright end and the faint end: The space density is highest at L Ly α ∗ = 10 43.4 erg s−1. We explore the evolution of the AGN LF over a broader redshift range (0.8 < z < 3); constructing the rest-frame ultraviolet (UV) LF with the 1450 Å monochromat...
American Astronomical Society Meeting Abstracts #233, 2019
Bulletin of the American Astronomical Society, Sep 30, 2019
The Astrophysical Journal Supplement Series, 2022
This paper documents the seventeenth data release (DR17) from the Sloan Digital Sky Surveys; the ... more This paper documents the seventeenth data release (DR17) from the Sloan Digital Sky Surveys; the fifth and final release from the fourth phase (SDSS-IV). DR17 contains the complete release of the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey, which reached its goal of surveying over 10,000 nearby galaxies. The complete release of the MaNGA Stellar Library accompanies this data, providing observations of almost 30,000 stars through the MaNGA instrument during bright time. DR17 also contains the complete release of the Apache Point Observatory Galactic Evolution Experiment 2 survey that publicly releases infrared spectra of over 650,000 stars. The main sample from the Extended Baryon Oscillation Spectroscopic Survey (eBOSS), as well as the subsurvey Time Domain Spectroscopic Survey data were fully released in DR16. New single-fiber optical spectroscopy released in DR17 is from the SPectroscipic IDentification of ERosita Survey subsurvey and the eBOSS-RM program. A...
Cornell University - arXiv, Mar 13, 2019
Galaxies evolve under the influence of gas flows between their interstellar medium and their surr... more Galaxies evolve under the influence of gas flows between their interstellar medium and their surrounding gaseous halos known as the circumgalactic medium (CGM). The CGM is a major reservoir of galactic baryons and metals, and plays a key role in the long cycles of accretion, feedback, and recycling of gas that drive star formation. In order to fully understand the physical processes at work within galaxies, it is therefore essential to have a firm understanding of the composition, structure, kinematics, thermodynamics, and evolution of the CGM. In this white paper we outline connections between the CGM and galactic star formation histories, internal kinematics, chemical evolution, quenching, satellite evolution, dark matter halo occupation, and the reionization of the larger-scale intergalactic medium in light of the advances that will be made on these topics in the 2020s. We argue that, in the next decade, fundamental progress on all of these major issues depends critically on improved empirical characterization and theoretical understanding of the CGM. In particular, we discuss how future advances in spatially-resolved CGM observations at high spectral resolution, broader characterization of the CGM across galaxy mass and redshift, and expected breakthroughs in cosmological hydrodynamic simulations will help resolve these major problems in galaxy evolution.
Using the conflict over Maunakea, this paper discusses ways in which astronomy has benefited from... more Using the conflict over Maunakea, this paper discusses ways in which astronomy has benefited from settler colonialism/white supremacist patriarchy, and the impact that has on communities that do not benefit from it. We advocate for astronomers to reject these benefits going forward, and we make 10 specific suggestions that will advance this effort.
arXiv: Astrophysics of Galaxies, 2019
The circumgalactic medium (CGM) of galaxies serves as a record of the influences of outflows and ... more The circumgalactic medium (CGM) of galaxies serves as a record of the influences of outflows and accretion that drive the evolution of galaxies. Feedback from star formation drives outflows that carry mass and metals away from galaxies to the CGM, while infall from the intergalactic medium (IGM) is thought to bring in fresh gas to fuel star formation. Such exchanges of matter between IGM-CGM-galaxies have proven critical to producing galaxy scaling relations in cosmological simulations that match observations. However, the nature of these processes, of the physics that drives outflows and accretion, and their evolution with cosmic time are not fully characterized. One approach to constraining these processes is to characterize the metal enrichment of gas around and beyond galaxies. Measurements of the metallicity distribution functions of CGM/IGM gas over cosmic time provide independent tests of cosmological simulations. We have made great progress over the last decade as direct res...
![Research paper thumbnail of HETDEX [O iii] Emitters. I. A Spectroscopically Selected Low-redshift Population of Low-mass, Low-metallicity Galaxies](https://attachments.academia-assets.com/95494325/thumbnails/1.jpg)
](The Astrophysical Journal, 2021
We assemble a sample of 17 low metallicity (7.45 < log(O/H)+12 < 8.12) galaxies with z 0.1 found ... more We assemble a sample of 17 low metallicity (7.45 < log(O/H)+12 < 8.12) galaxies with z 0.1 found spectroscopically, without photometric pre-selection, in early data from the Hobby Eberly Telescope Dark Energy Experiment (HETDEX). Star forming galaxies that occupy the lowest mass and metallicity end of the mass-metallicity relation tend to be under sampled in continuum-based surveys as their spectra are typically dominated by emission from newly forming stars. We search for galaxies with high [O III]λ5007 / [O II]λ3727, implying highly ionized nebular emission often indicative of low metallicity systems. With the Second Generation Low Resolution Spectrograph on the Hobby Eberly Telescope we acquired follow-up spectra, with higher resolution and broader wavelength coverage, of each low-metallicity candidate in order to confirm the redshift, measure the Hα and [N II] line strengths and, in many cases, obtain deeper spectra of the blue lines. We find our galaxies are consistent with the mass-metallicity relation of typical low mass galaxies. However, galaxies in our sample tend to have similar specific star formation rates (sSFRs) as the incredibly rare "blueberry" galaxies found in Yang et al. (2017a). We illustrate the power of spectroscopic surveys for finding low mass and metallicity galaxies and reveal that we find a sample of galaxies that are a hybrid between the properties of typical dwarf galaxies and the more extreme blueberry galaxies.
Bulletin of the American Astronomical Society, 2019
arXiv: Instrumentation and Methods for Astrophysics, 2019
Organizations that support science (astronomy) such as federal agencies, research centers, observ... more Organizations that support science (astronomy) such as federal agencies, research centers, observatories, academic institutions, societies, etc. employ advisory committees and boards as a mechanism for reviewing their activities and giving advice on practices, policies and future directions. As with any scientific endeavor, there is concern over complementing these committees with enough members who have as broad a range of expertise and understanding as possible, so that bias is mitigated. However, for a number of reasons (logistical, practical, financial, etc.), committees can also not be infinitely large and thus trade-offs must be made. It is often recognized that conflicts of interest must be acknowledged within these committees, but what is not often recognized it the potential for unmitigated biases and "group think" that can be introduced as part of these committees. In this white paper, we recommend that advisory committees that collect community input, (e.g., the...
Bulletin of the American Astronomical Society, 2019
We describe the Sloan Digital Sky Survey (SDSS) as an archetypal mid-scale program, including the... more We describe the Sloan Digital Sky Survey (SDSS) as an archetypal mid-scale program, including the technical, scientific, and organizational aspects underpinning its success over the last twenty years. Based on the SDSS experience, we present six recommendations that the funding mechanisms for mid-scale programs should be designed to ensure.
arXiv: Instrumentation and Methods for Astrophysics, 2019
The Committee on the Status of Women in Astronomy (CSWA) is calling on federal science funding ag... more The Committee on the Status of Women in Astronomy (CSWA) is calling on federal science funding agencies, in their role as the largest sources of funding for astronomy in the United States, to take actions that will advance career development and improve workplace conditions for women and minorities in astronomy. Funding agencies can and should lead the charge to produce excellent diversity and inclusion outcomes in our field by the 2030 Astrophysics Decadal Survey. Anecdotal and quantitative evidence, gathered both by the CSWA and other groups, shows that many structural barriers to success remain in our community. We acknowledge the success of programs like NSF-INCLUDES and NSF-ADVANCE and endorse their continued work. We also recommend further action to remove barriers to success for women and minority astronomers. Key recommendations are: - Federal agencies should push academic institutions to reconsider their support systems for scientists by requiring a high standard of pay and...
arXiv: Astrophysics of Galaxies, 2019
Crucial progress in our understanding of star formation and feedback will depend on the ability t... more Crucial progress in our understanding of star formation and feedback will depend on the ability to obtain spatially resolved spectroscopic observations of \ion{H}{ii} regions, from which reliable instantaneous measurements of their physical conditions can be obtained. Acquiring these datasets across full galactic systems will prove crucial for obtaining population samples that enable us to understand the time evolution of similar regions, and the variability of conditions among coeval regions. Separating the spatial and temporal dependencies in such way for different physical processes involved in star formation and the injection of feedback is crucial to overcome the inherit degeneracies associated with observing instantaneous snapshots of a dynamic ISM at any given time. Emission line diagnostics are at the core of measuring the physical condition in \ion{H}{ii} regions (e.g. dynamics, SFR, chemical abundances, dust extinction, ionization and excitation, etc.). These measurements ...
The Astronomical Journal, 2021
Robotic fiber positioner (RFP) arrays are becoming heavily adopted in wide-field massively multip... more Robotic fiber positioner (RFP) arrays are becoming heavily adopted in wide-field massively multiplexed spectroscopic survey instruments. RFP arrays decrease nightly operational overheads through rapid reconfiguration between fields and exposures. In comparison to similar instruments, SDSS-V has selected a very dense RFP packing scheme where any point in a field is typically accessible to three or more robots. This design provides flexibility in target assignment. However, the task of collisionless trajectory planning is especially challenging. We present two multiagent distributed control strategies that are highly efficient and computationally inexpensive for determining collision-free paths for RFPs in heavily overlapping workspaces. We demonstrate that a reconfiguration path between two arbitrary robot configurations can be efficiently found if a “folded” state, in which all robot arms are retracted and aligned in a lattice-like orientation, is inserted between the initial and fi...
The Astrophysical Journal
We present the first publicly released catalog of sources obtained from the Hobby-Eberly Telescop... more We present the first publicly released catalog of sources obtained from the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX). HETDEX is an integral field spectroscopic survey designed to measure the Hubble expansion parameter and angular diameter distance at 1.88 < z < 3.52 by using the spatial distribution of more than a million Lyα-emitting galaxies over a total target area of 540 deg2. The catalog comes from contiguous fiber spectra coverage of 25 deg2 of sky from 2017 January through 2020 June, where object detection is performed through two complementary detection methods: one designed to search for line emission and the other a search for continuum emission. The HETDEX public release catalog is dominated by emission-line galaxies and includes 51,863 Lyα-emitting galaxy (LAE) identifications and 123,891 [O ii]-emitting galaxies at z < 0.5. Also included in the catalog are 37,916 stars, 5274 low-redshift (z < 0.5) galaxies without emission lines, and 4976 activ...
Cornell University - arXiv, Jul 10, 2019
One outcome of the 2015 Inclusive Astronomy conference was the establishment of an accessibility/... more One outcome of the 2015 Inclusive Astronomy conference was the establishment of an accessibility/disability advocacy group within professional, US-based astronomy, organized by a coalition of disabled astronomers and allies and is supported by the American Astronomical Society (AAS). While the Working Group on Accessibility and Disability (WGAD 1) has focused on AAS-led initiatives to increase the accessibility of publications, databases, and professional meetings, there is an urgent need to expand these accessibility efforts beyond the professional society and into the wider astronomical community. Our long-term goals include proactively designing learning and working environments to be as accessible as possible, the removal of existing physical, technological, and pedagogical barriers to access, and provision of greater support for the career progress, promotion, and retention of disabled astronomers and educators. Progress toward these goals can be made by establishing and then sustaining a culture of inclusion in which all identities and intersections of identity are equally represented, while recognizing that progress which liberates one identity group may not liberate another in the same way. In the decades since the passage of the Americans with Disabilities Act (ADA), it has become clear that academic departments and research institutions will only undertake the necessary cultural and infrastructure changes if motivated by clear guidelines from funding organizations or ADA non-compliance lawsuits 2 , 3 , 4. In this white paper, we outline the major barriers to access within the educational and professional practice of astronomy. We present current best practices for inclusivity and accessibility, including classroom practices, institutional culture, support for infrastructure creation, hiring processes, and outreach initiatives. We present specific ways-beyond simple compliance with the ADA-that funding agencies, astronomers, and institutions can work together to make astronomy as a field more accessible, inclusive, and equitable. In particular, funding agencies should include the accessibility of institutions during proposal evaluation, hold institutions accountable for inaccessibility, and support efforts to gather data on the status and progress of astronomers and astronomy students with disabilities.
Cornell University - arXiv, Aug 7, 2019
Ground-based and Airborne Instrumentation for Astronomy IX
The Astrophysical Journal
We present the Lyα emission line luminosity function (LF) of the active galactic nuclei (AGN) in ... more We present the Lyα emission line luminosity function (LF) of the active galactic nuclei (AGN) in the first release of the Hobby–Eberly Telescope Dark Energy Experiment Survey (HETDEX) AGN catalog. The AGN are selected either by emission line pairs characteristic of AGN or by a single broad emission line, free of any photometric preselections (magnitude/color/morphology). The sample consists of 2346 AGN spanning 1.88 < z < 3.53, covering an effective area of 30.61 deg2. Approximately 2.6% of the HETDEX AGN are not detected at >5σ confidence at r ∼ 26 in the deepest r-band images we have searched. The Lyα line luminosity ranges from ∼1042.3 to 1045.9 erg s−1. Our Lyα LF shows a turnover luminosity with opposite slopes on the bright end and the faint end: The space density is highest at L Ly α ∗ = 10 43.4 erg s−1. We explore the evolution of the AGN LF over a broader redshift range (0.8 < z < 3); constructing the rest-frame ultraviolet (UV) LF with the 1450 Å monochromat...
American Astronomical Society Meeting Abstracts #233, 2019
Bulletin of the American Astronomical Society, Sep 30, 2019
The Astrophysical Journal Supplement Series, 2022
This paper documents the seventeenth data release (DR17) from the Sloan Digital Sky Surveys; the ... more This paper documents the seventeenth data release (DR17) from the Sloan Digital Sky Surveys; the fifth and final release from the fourth phase (SDSS-IV). DR17 contains the complete release of the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey, which reached its goal of surveying over 10,000 nearby galaxies. The complete release of the MaNGA Stellar Library accompanies this data, providing observations of almost 30,000 stars through the MaNGA instrument during bright time. DR17 also contains the complete release of the Apache Point Observatory Galactic Evolution Experiment 2 survey that publicly releases infrared spectra of over 650,000 stars. The main sample from the Extended Baryon Oscillation Spectroscopic Survey (eBOSS), as well as the subsurvey Time Domain Spectroscopic Survey data were fully released in DR16. New single-fiber optical spectroscopy released in DR17 is from the SPectroscipic IDentification of ERosita Survey subsurvey and the eBOSS-RM program. A...
Cornell University - arXiv, Mar 13, 2019
Galaxies evolve under the influence of gas flows between their interstellar medium and their surr... more Galaxies evolve under the influence of gas flows between their interstellar medium and their surrounding gaseous halos known as the circumgalactic medium (CGM). The CGM is a major reservoir of galactic baryons and metals, and plays a key role in the long cycles of accretion, feedback, and recycling of gas that drive star formation. In order to fully understand the physical processes at work within galaxies, it is therefore essential to have a firm understanding of the composition, structure, kinematics, thermodynamics, and evolution of the CGM. In this white paper we outline connections between the CGM and galactic star formation histories, internal kinematics, chemical evolution, quenching, satellite evolution, dark matter halo occupation, and the reionization of the larger-scale intergalactic medium in light of the advances that will be made on these topics in the 2020s. We argue that, in the next decade, fundamental progress on all of these major issues depends critically on improved empirical characterization and theoretical understanding of the CGM. In particular, we discuss how future advances in spatially-resolved CGM observations at high spectral resolution, broader characterization of the CGM across galaxy mass and redshift, and expected breakthroughs in cosmological hydrodynamic simulations will help resolve these major problems in galaxy evolution.
Using the conflict over Maunakea, this paper discusses ways in which astronomy has benefited from... more Using the conflict over Maunakea, this paper discusses ways in which astronomy has benefited from settler colonialism/white supremacist patriarchy, and the impact that has on communities that do not benefit from it. We advocate for astronomers to reject these benefits going forward, and we make 10 specific suggestions that will advance this effort.
arXiv: Astrophysics of Galaxies, 2019
The circumgalactic medium (CGM) of galaxies serves as a record of the influences of outflows and ... more The circumgalactic medium (CGM) of galaxies serves as a record of the influences of outflows and accretion that drive the evolution of galaxies. Feedback from star formation drives outflows that carry mass and metals away from galaxies to the CGM, while infall from the intergalactic medium (IGM) is thought to bring in fresh gas to fuel star formation. Such exchanges of matter between IGM-CGM-galaxies have proven critical to producing galaxy scaling relations in cosmological simulations that match observations. However, the nature of these processes, of the physics that drives outflows and accretion, and their evolution with cosmic time are not fully characterized. One approach to constraining these processes is to characterize the metal enrichment of gas around and beyond galaxies. Measurements of the metallicity distribution functions of CGM/IGM gas over cosmic time provide independent tests of cosmological simulations. We have made great progress over the last decade as direct res...
The Astrophysical Journal, 2021
We assemble a sample of 17 low metallicity (7.45 < log(O/H)+12 < 8.12) galaxies with z 0.1 found ... more We assemble a sample of 17 low metallicity (7.45 < log(O/H)+12 < 8.12) galaxies with z 0.1 found spectroscopically, without photometric pre-selection, in early data from the Hobby Eberly Telescope Dark Energy Experiment (HETDEX). Star forming galaxies that occupy the lowest mass and metallicity end of the mass-metallicity relation tend to be under sampled in continuum-based surveys as their spectra are typically dominated by emission from newly forming stars. We search for galaxies with high [O III]λ5007 / [O II]λ3727, implying highly ionized nebular emission often indicative of low metallicity systems. With the Second Generation Low Resolution Spectrograph on the Hobby Eberly Telescope we acquired follow-up spectra, with higher resolution and broader wavelength coverage, of each low-metallicity candidate in order to confirm the redshift, measure the Hα and [N II] line strengths and, in many cases, obtain deeper spectra of the blue lines. We find our galaxies are consistent with the mass-metallicity relation of typical low mass galaxies. However, galaxies in our sample tend to have similar specific star formation rates (sSFRs) as the incredibly rare "blueberry" galaxies found in Yang et al. (2017a). We illustrate the power of spectroscopic surveys for finding low mass and metallicity galaxies and reveal that we find a sample of galaxies that are a hybrid between the properties of typical dwarf galaxies and the more extreme blueberry galaxies.
Bulletin of the American Astronomical Society, 2019
arXiv: Instrumentation and Methods for Astrophysics, 2019
Organizations that support science (astronomy) such as federal agencies, research centers, observ... more Organizations that support science (astronomy) such as federal agencies, research centers, observatories, academic institutions, societies, etc. employ advisory committees and boards as a mechanism for reviewing their activities and giving advice on practices, policies and future directions. As with any scientific endeavor, there is concern over complementing these committees with enough members who have as broad a range of expertise and understanding as possible, so that bias is mitigated. However, for a number of reasons (logistical, practical, financial, etc.), committees can also not be infinitely large and thus trade-offs must be made. It is often recognized that conflicts of interest must be acknowledged within these committees, but what is not often recognized it the potential for unmitigated biases and "group think" that can be introduced as part of these committees. In this white paper, we recommend that advisory committees that collect community input, (e.g., the...
Bulletin of the American Astronomical Society, 2019
We describe the Sloan Digital Sky Survey (SDSS) as an archetypal mid-scale program, including the... more We describe the Sloan Digital Sky Survey (SDSS) as an archetypal mid-scale program, including the technical, scientific, and organizational aspects underpinning its success over the last twenty years. Based on the SDSS experience, we present six recommendations that the funding mechanisms for mid-scale programs should be designed to ensure.
arXiv: Instrumentation and Methods for Astrophysics, 2019
The Committee on the Status of Women in Astronomy (CSWA) is calling on federal science funding ag... more The Committee on the Status of Women in Astronomy (CSWA) is calling on federal science funding agencies, in their role as the largest sources of funding for astronomy in the United States, to take actions that will advance career development and improve workplace conditions for women and minorities in astronomy. Funding agencies can and should lead the charge to produce excellent diversity and inclusion outcomes in our field by the 2030 Astrophysics Decadal Survey. Anecdotal and quantitative evidence, gathered both by the CSWA and other groups, shows that many structural barriers to success remain in our community. We acknowledge the success of programs like NSF-INCLUDES and NSF-ADVANCE and endorse their continued work. We also recommend further action to remove barriers to success for women and minority astronomers. Key recommendations are: - Federal agencies should push academic institutions to reconsider their support systems for scientists by requiring a high standard of pay and...
arXiv: Astrophysics of Galaxies, 2019
Crucial progress in our understanding of star formation and feedback will depend on the ability t... more Crucial progress in our understanding of star formation and feedback will depend on the ability to obtain spatially resolved spectroscopic observations of \ion{H}{ii} regions, from which reliable instantaneous measurements of their physical conditions can be obtained. Acquiring these datasets across full galactic systems will prove crucial for obtaining population samples that enable us to understand the time evolution of similar regions, and the variability of conditions among coeval regions. Separating the spatial and temporal dependencies in such way for different physical processes involved in star formation and the injection of feedback is crucial to overcome the inherit degeneracies associated with observing instantaneous snapshots of a dynamic ISM at any given time. Emission line diagnostics are at the core of measuring the physical condition in \ion{H}{ii} regions (e.g. dynamics, SFR, chemical abundances, dust extinction, ionization and excitation, etc.). These measurements ...
The Astronomical Journal, 2021
Robotic fiber positioner (RFP) arrays are becoming heavily adopted in wide-field massively multip... more Robotic fiber positioner (RFP) arrays are becoming heavily adopted in wide-field massively multiplexed spectroscopic survey instruments. RFP arrays decrease nightly operational overheads through rapid reconfiguration between fields and exposures. In comparison to similar instruments, SDSS-V has selected a very dense RFP packing scheme where any point in a field is typically accessible to three or more robots. This design provides flexibility in target assignment. However, the task of collisionless trajectory planning is especially challenging. We present two multiagent distributed control strategies that are highly efficient and computationally inexpensive for determining collision-free paths for RFPs in heavily overlapping workspaces. We demonstrate that a reconfiguration path between two arbitrary robot configurations can be efficiently found if a “folded” state, in which all robot arms are retracted and aligned in a lattice-like orientation, is inserted between the initial and fi...