Developing and supporting professional communities of mathematics teachers in Nebraska

For a number of years, the University of Nebraska-Lincoln has focused on building a statewide partnership with mathematics teachers, schools, districts, and educational service units, to raise K-12 student achievement in mathematics. During this session, we will share a variety of our efforts to build professional communities of educators, including the NSF-funded grants NebraskaNOYCE, NebraskaMATH, and the Math in the Middle Institute Partnership. We will engage participants in a discussion of necessary and sufficient conditions to support such professional communities, and how such conditions can be created or worked around

Le FORUM, Vol. 36 No. 4

https://digitalcommons.library.umaine.edu/francoamericain_forum/1035/thumbnail.jp

Reverberation Mapping of the Kepler-Field AGN KA1858+4850

KA1858+4850 is a narrow-line Seyfert 1 galaxy at redshift 0.078 and is among the brightest active galaxies monitored by the Kepler mission. We have carried out a reverberation mapping campaign designed to measure the broad-line region size and estimate the mass of the black hole in this galaxy. We obtained 74 epochs of spectroscopic data using the Kast Spectrograph at the Lick 3-m telescope from February to November of 2012, and obtained complementary V-band images from five other ground-based telescopes. We measured the H-beta light curve lag with respect to the V-band continuum light curve using both cross-correlation techniques (CCF) and continuum light curve variability modeling with the JAVELIN method, and found rest-frame lags of lag_CCF = 13.53 (+2.03, -2.32) days and lag_JAVELIN = 13.15 (+1.08, -1.00) days. The H-beta root-mean-square line profile has a width of sigma_line = 770 +/- 49 km/s. Combining these two results and assuming a virial scale factor of f = 5.13, we obtained a virial estimate of M_BH = 8.06 (+1.59, -1.72) x 10^6 M_sun for the mass of the central black hole and an Eddington ratio of L/L_Edd ~ 0.2. We also obtained consistent but slightly shorter emission-line lags with respect to the Kepler light curve. Thanks to the Kepler mission, the light curve of KA1858+4850 has among the highest cadences and signal-to-noise ratios ever measured for an active galactic nucleus; thus, our black hole mass measurement will serve as a reference point for relations between black hole mass and continuum variability characteristics in active galactic nuclei

Le FORUM, Vol. 35 No. 4

https://digitalcommons.library.umaine.edu/francoamericain_forum/1032/thumbnail.jp

The LIGO HET Response (LIGHETR) Project to Discover and Spectroscopically Follow Optical Transients Associated with Neutron Star Mergers

The LIGO HET Response (LIGHETR) project is an enterprise to follow up optical transients (OT) discovered as gravitational wave merger sources by the LIGO/Virgo collaboration (LVC). Early spectroscopy has the potential to constrain crucial parameters such as the aspect angle. The LIGHETR collaboration also includes the capacity to model the spectroscopic evolution of mergers to facilitate a real-time direct comparison of models with our data. The principal facility is the Hobby-Eberly Telescope. LIGHETR uses the massively-replicated VIRUS array of spectrographs to search for associated OTs and obtain early blue spectra and in a complementary role, the low-resolution LRS-2 spectrograph is used to obtain spectra of viable candidates as well as a densely-sampled series of spectra of true counterparts. Once an OT is identified, the anticipated cadence of spectra would match or considerably exceed anything achieved for GW170817 = AT2017gfo for which there were no spectra in the first 12 hours and thereafter only roughly once daily. We describe special HET-specific software written to facilitate the program and attempts to determine the flux limits to undetected sources. We also describe our campaign to follow up OT candidates during the third observational campaign of the LIGO and Virgo Scientific Collaborations. We obtained VIRUS spectroscopy of candidate galaxy hosts for 5 LVC gravitational wave events and LRS-2 spectra of one candidate for the OT associated with S190901ap. We identified that candidate, ZTF19abvionh = AT2019pip, as a possible Wolf-Rayet star in an otherwise unrecognized nearby dwarf galaxy.Comment: 26 pages, 15 figure

ngVLA Key Science Goal 5 Understanding the Formation and Evolution of Black Holes in the Era of Multi-Messenger Astronomy

The next-generation Very Large Array (ngVLA) will be a powerful telescope for finding and studying black holes across the entire mass range. High-resolution imaging abilities will allow the separation of low-luminosity black holes in the local Universe from background sources, thereby providing critical constraints on the mass function, formation, and growth of black holes. Its combination of sensitivity and angular resolution will provide new constraints on the physics of black hole accretion and jet formation. Combined with facilities across the spectrum and gravitational wave observatories, the ngVLA will provide crucial constraints on the interaction of black holes with their environments, with specific implications for the relationship between evolution of galaxies and the emission of gravitational waves from in-spiraling supermassive black holes and potential implications for stellar mass and intermediate mass black holes. The ngVLA will identify the radio counterparts to transient sources discovered by electromagnetic, gravitational wave, and neutrino observatories, and its high-resolution, fast-mapping capabilities will make it the preferred instrument to pinpoint electromagnetic counterparts to events such as supermassive black hole mergers. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration

Believe Our Stories & Listen: Portland Street Response Survey Report

Many advocates, local officials, and people experiencing homelessness agree that Portland needs a better way to respond to low-priority calls for service involving those experiencing homelessness and behavioral health crises. This report examines efforts to address homelessness in Portland through the development of a plan to dispatch the Portland Street Response unit rather than police. A team of community partners spread out across the city July 16 and 18 to interview people experiencing homelessness to help inform the design of the Portland Street Response pilot project (PSR). An additional team went out on Sept. 6. Members of Street Roots, Sisters of the Road, Right 2 Survive, Street Books, the Portland State University Homelessness Research & Action Collaborative, the Map- ping Action Collective, Yellow Brick Road, Commissioner Jo Ann Hardesty’s office, and Alissa Keny-Guyer’s office interviewed 184 unhoused people. Participants formed teams of two to three, each lead by a Street Roots vendor or someone else who had experienced homelessness. Teams engaged people experiencing homelessness in discussions about what the PSR pilot should look like, including who the first responders should be, how they should approach individuals in crisis, what types of services and resources they should bring with them, and what types of training they should have. Following the interviews, responses were analyzed and summarized into this report to provide guidance for this important initiative based directly on the needs and experiences of unhoused people