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  1. Abstract Virgo is the nearest galaxy cluster; it is thus ideal for studies of galaxy evolution in dense environments in the local universe. It is embedded in a complex filamentary network of galaxies and groups, which represents the skeleton of the large-scale Laniakea supercluster. Here we assemble a comprehensive catalog of galaxies extending up to ∼12 virial radii in projection from Virgo to revisit the cosmic-web structure around it. This work is the foundation of a series of papers that will investigate the multiwavelength properties of galaxies in the cosmic web around Virgo. We match spectroscopically confirmed sources from severalmore »databases and surveys including HyperLeda, NASA Sloan Atlas, NASA/IPAC Extragalactic Database, and ALFALFA. The sample consists of ∼7000 galaxies. By exploiting a tomographic approach, we identify 13 filaments, spanning several megaparsecs in length. Long >17 h –1 Mpc filaments, tend to be thin (<1 h –1 Mpc in radius) and with a low-density contrast (<5), while shorter filaments show a larger scatter in their structural properties. Overall, we find that filaments are a transitioning environment between the field and cluster in terms of local densities, galaxy morphologies, and fraction of barred galaxies. Denser filaments have a higher fraction of early-type galaxies, suggesting that the morphology–density relation is already in place in the filaments, before galaxies fall into the cluster itself. We release the full catalog of galaxies around Virgo and their associated properties.« less
    Free, publicly-accessible full text available March 23, 2023
  2. This White Paper highlights the role Primarily Undergraduate Institutions (PUIs) play within the astronomy profession, addressing issues related to employment, resources and support, research opportunities and productivity, and educational and societal impacts.
  3. The NSF-sponsored Undergraduate ALFALFA (Arecibo Legacy Fast ALFA) Team (UAT) is a collaborative, multifaceted program of faculty and undergraduate research at a consortium of 23 diverse U.S. institutions, founded to promote undergraduate research and faculty development within the extragalactic ALFALFA HI blind survey project and follow-up programs. The objective of the UAT is to provide opportunities for faculty and students from a wide range of public and private colleges and especially those with small astronomy programs to learn how science is accomplished in a large collaboration while contributing to the scientific goals of a legacy radio astronomy survey. Partnering withmore »Arecibo and Green Bank Observatories, the UAT has worked with 334 undergraduates (40% women) and 32 (48% women) faculty in the past 10 years, offering annual workshops, observing runs, and research projects (academic year and sumer), and presentation of results at national meetings such as the AAS (at AAS233: Burhenne et al., Cane et al., Gault et al., Hetrick et al., Jong et al., Kumagai et al., Luna et al., Olivieri Villalvazo et al., Page et al., Poulin et al., Rea et al., Rehmn et al., Reiter et al., ). In this presentation, we summarize the UAT program and outcomes, highlight several current Team research efforts, including multiwavelength followup observations of ALFALFA sources, the UAT Collaborative Groups Project, and the Arecibo Pisces-Perseus Supercluster Survey (APPSS), and suggest how our model could be applied to other legacy projects. This work has been supported by NSF grants AST-0724918/0902211, AST-075267/0903394, AST-0725380, AST-1211005, AST-1211683, and AST-1637339.« less
  4. The Arecibo Pisces-Perseus Supercluster Survey (APPSS) attempts to detect the infall of galaxies onto the Pisces-Perseus Supercluster (PPS). The ALFALFA survey has greatly augmented the known redshifts across the region. APPSS sources will complement the ALFALFA sources, with the goal of building a large enough sample to make a high confidence measurement of infall and backflow onto the PSS filament via peculiar velocity estimates from the Tully-Fisher (TFR) and Baryonic Tully-Fisher (BTFR) relations. APPSS galaxies are selected using photometric data from the Sloan Digital Sky Survey (SDSS), aimed to detect low-mass, nearby gas-rich objects below the ALFALFA detection limit. Themore »L-band wide receiver at Arecibo Observatory in Puerto Rico is used to obtain a five-minute ON-OFF measurement for each galaxy. Since the candidate galaxy redshifts are unknown, the receiver and spectrograph system are used in a search mode that spans the expected frequencies of HI emission from PPS galaxies. We will describe the goals, target selection, and data reduction process for the survey. Our collaboration has divided the PPS into two-degree wide declination strips for data reduction; we report preliminary results for strips 23 and 33. We have made the initial data reduction on more than 200 targets, and determined the systemic velocity, line width, integrated flux density, and HI mass for each candidate detection. We will compare results on our two declination strips, and point out interesting detections found along the way as examples of the data reduction process. This work has been supported by NSF grants AST-1211005 and AST-1637339. Publication: American Astronomical Society, AAS Meeting #233, id.356.07 Pub Date: January 2019 Bibcode: 2019AAS...23335607L« less
  5. The Arecibo Pisces-Perseus Supercluster Survey (APPSS) attempts to detect the infall of galaxies onto the Pisces-Perseus Supercluster (PPS). The ALFALFA survey has greatly augmented the known redshifts across the region. APPSS sources will complement the ALFALFA sources, with the goal of building a large enough sample to make a high confidence measurement of infall and backflow onto the PSS filament via peculiar velocity estimates from the Tully-Fisher (TFR) and Baryonic Tully-Fisher (BTFR) relations. APPSS galaxies are selected using photometric data from the Sloan Digital Sky Survey (SDSS), aimed to detect low-mass, nearby gas-rich objects below the ALFALFA detection limit. Themore »L-band wide receiver at Arecibo Observatory in Puerto Rico is used to obtain a five-minute ON-OFF measurement for each galaxy. Since the candidate galaxy redshifts are unknown, the receiver and spectrograph system are used in a search mode that spans the expected frequencies of HI emission from PPS galaxies. We will describe the goals, target selection, and data reduction process for the survey. Our collaboration has divided the PPS into two-degree wide declination strips for data reduction; we report preliminary results for strips 23 and 33. We have made the initial data reduction on more than 200 targets, and determined the systemic velocity, line width, integrated flux density, and HI mass for each candidate detection. We will compare results on our two declination strips, and point out interesting detections found along the way as examples of the data reduction process. This work has been supported by NSF grants AST-1211005 and AST-1637339.« less
  6. The Undergraduate ALFALFA Team (UAT) Groups project is a coordinated study of gas and star formation properties of galaxies in and around more than 50 nearby (z<0.03) groups and clusters of varied richness, morphological type mix, and X-ray luminosity. We aim to probe mechanisms of gas depletion and morphological transformation by considering the spatial distributions of star formation in galaxies inhabiting a wide range of group and cluster environments. Here we present recent results from our wide area Hα and broadband R imaging project carried out with the WIYN 0.9m+MOSAIC/HDI at KPNO. This work has been supported by NSF grantmore »AST-1211005 and AST-1637339.« less
  7. We present results from a highly successful model of faculty development and undergraduate research and education, the Undergraduate ALFALFA Team (UAT), an NSF-sponsored 23-institution collaboration. We recommend that granting agencies identify funding resources to support similar efforts for other large-scale scientific projects.
  8. The Arecibo Pisces-Perseus Supercluster Survey (APPSS) will provide strong observational constraints on the infall rate onto the main filament of the Pisces-Perseus Supercluster. The survey data consist of HI emission-line galaxies in the PPS region, obtained primarily at the Arecibo Observatory. Here we present data from Declination strips 27 and 29, which include 308 target galaxies, and describe our method for deducing the dark matter distribution in the filament from galaxy peculiar velocities by comparison to similar filaments in the Millennium simulation. This work has been supported by NSF grants AST-1211005 and AST-1637339.