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  1. We have completed three “Harvesting ALFALFA” Arecibo observing programs in the direction of the Pisces-Perseus Supercluster (PPS) since ALFALFA observations were finished in 2012. The first was to perform follow-up observations on high signal-to-noise (S/N > 6.5) ALFALFA detections needing confirmation and low S/N sources lacking optical counterparts. A few more high S/N objects were observed in the second program along with targets visually selected from the Sloan Digital Sky Survey (SDSS). The third program included low S/N ALFALFA sources having optical counterparts with redshifts that were unknown or differed from the ALFALFA observations. It also included more galaxies selectedmore »from SDSS by eye and by Structured Query Language (SQL) searches with parameters intended to select galaxies at the distance of the PPS (~6,000 km/s). We used pointed basic Total-Power Position-Switched Observations in the 1340 - 1430 MHz ALFALFA frequency range. For sources of known redshift, we used the Wideband Arecibo Pulsar Processors (WAPP’s) , while for sources of unknown redshift we utilized a hybrid/dual bandwidth Doppler tracking mode using the Arecibo Interim 50-MHz Correlator with 9-level sampling.Results confirmed that a few high S/N ALFALFA sources are spurious as expected from the work of Saintonge (2007), low S/N ALFALA sources lacking an optical counterpart are all likely to be spurious, but low S/N sources with optical counterparts are generally reliable. Of the optically selected sources, about 80% were detected and tended to be near the distance of the PPS.This work has been supported by NSF grant AST-1211005.« less
  2. The Undergraduate ALFALFA Team (UAT) Groups project is a coordinated study of gas and star formation properties of galaxies in and around 36 nearby (z<0.03) groups and clusters of varied richness, morphological type mix, and X-ray luminosity. By studying a large range of environments and considering the spatial distributions of star formation, we probe mechanisms of gas depletion and morphological transformation. The project uses ALFALFA HI observations, optical observations, and digital databases like SDSS, and incorporates work undertaken by faculty and students at different institutions within the UAT. Here we present results from our wide area Hα and broadband Rmore »imaging project carried out with the WIYN 0.9m+MOSAIC/HDI at KPNO, including an analysis of radial star formation rates and extents of galaxies in the NGC 5846, Abell 779, NRGb331, and HCG 69 groups/clusters. This work has been supported by NSF grant AST-1211005 and AST-1637339.« less
  3. The Arecibo Pisces-Perseus Supercluster Survey is a targeted HI survey of galaxies that began its second observing season in October 2016. The survey is conducted by members of the Undergraduate ALFALFA Team (UAT) and extensively involves undergraduates in observations, data reduction, and analysis. It aims to complement the HI sources identified by the ALFALFA extragalactic HI line survey by probing deeper in HI mass (to lower masses) than the legacy survey itself. Measurements of the HI line velocity widths will be combined with uniform processing of images obtained in the SDSS and GALEX public databases to localize the sample withinmore »the baryonic Tully Fisher relation, allowing estimates of their redshift-independent distances and thus their peculiar velocities.The survey is designed to constrain Pisces-Perseus Supercluster infall models by producing 5-σ detections of infall velocities to a precision of about 500 km/s. By targeting galaxies based on SDSS and GALEX photometry, we have achieved detection rates of 68% of the galaxies in our sample. We will discuss the target selection process, HI velocities and mass estimates from the 2015 fall observing season, preliminary results from 2016 observations, and preliminary comparisons with inflow models predicted by numerical simulations.This work has been supported by NSF grants AST-1211005, AST-1637339, AST-1637262.« less
  4. The NSF-sponsored Undergraduate ALFALFA (Arecibo Legacy Fast ALFA) Team (UAT) is a consortium of 20 institutions across the US and Puerto Rico, 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 its members to develop expertise in the technical aspects of observational radio spectroscopy, its associated data analysis, and the motivating science. Partnering with Arecibo Observatory, the UAT has worked with more than 280 undergraduates and 26 faculty to date, offering 8 workshops onsite at Arecibo (148 undergraduates), observing runsmore »at Arecibo (69 undergraduates), remote observing runs on campus, undergraduate research projects based on Arecibo science (120 academic year and 185 summer projects), and presentation of results at national meetings such as the AAS (at AAS229: Ball et al., Collova et al., Davis et al., Miazzo et al., Ruvolo et al, Singer et al., Cannon et al., Craig et al., Koopmann et al., O'Donoghue et al.). 40% of the students and 45% of the faculty participants have been women and members of underrepresented groups. More than 90% of student alumni are attending graduate school and/or pursuing a career in STEM. 42% of those pursuing graduate degrees in Physics or Astronomy are women.In this presentation, we summarize the UAT program and the current research efforts of UAT members based on Arecibo science, including multiwavelength followup observations of ALFALFA sources, the UAT Collaborative Groups Project, the Survey of HI in Extremely Low-mass Dwarfs (SHIELD), and the Arecibo Pisces-Perseus Supercluster Survey (APPSS). This work has been supported by NSF grants AST-0724918/0902211, AST-075267/0903394, AST-0725380, AST-121105, and AST-1637339.« less