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Earning a postsecondary degree or credential is increasingly important for individuals to succeed in the rapidly changing, global economy. College access programs like Gaining Early Awareness and R...

Gaining Early Awareness and Readiness for Undergraduate Programs (GEAR UP) is a federal program designed to promote postsecondary readiness and success among low-income students. Some evidence suggests that this program promotes college enrollment and persistence, but GEAR UP may include a wide variety of services, and it is unclear which ones actually contribute to these apparent overall effects. The present study investigates this issue using doubly robust propensity score analyses to provide stronger causal conclusions. Four general service types and seven specific services were examined; the results provide important implications for GEAR UP and other programs designed to promote postsecondary attainment.

GEAR UP (Gaining Early Awareness and Readiness for Undergraduate Programs) is a federal program designed to promote college access and success for students from low-income backgrounds. Although some literature has examined K–12 outcomes, little research has explored the extent to which GEAR UP achieves its intended postsecondary objectives. The present study used a difference-in-differences design with a sample of 17,605 students to explore the impact of GEAR UP Iowa on college enrollment and persistence. The findings indicate that GEAR UP Iowa promotes the college enrollment of high school graduates by 3 to 4 percentage points, whereas it appears to have no effect on college persistence. Results are similar regardless of students’ socioeconomic status, race/ethnicity, sex, and K–12 special education status.

We report FUV, optical, and NIR observations of three T Tauri stars in the Orion OB1b subassociation with H$\alpha$ equivalent widths consistent with low or absent accretion and various degrees of excess flux in the mid-infrared. We aim to search for evidence of gas in the inner disk in HST ACS/SBC spectra, and to probe the accretion flows onto the star using H$\alpha$ and He I $\lambda$10830 in spectra obtained at the Magellan and SOAR telescopes. At the critical age of 5 Myr, the targets are at different stages of disk evolution. One of our targets is clearly accreting, as shown by redshifted absorption at free-fall velocities in the He I line and wide wings in H$\alpha$; however, a marginal detection of FUV H$_2$ suggests that little gas is present in the inner disk, although the spectral energy distribution indicates that small dust still remains close to the star. Another target is surrounded by a transitional disk, with an inner cavity in which little sub-micron dust remains. Still, the inner disk shows substantial amounts of gas, accreting onto the star at a probably low, but uncertain rate. The third target lacks both a He I line or FUV emission, consistent with no accretion or inner gas disk; its very weak IR excess is consistent with a debris disk. Different processes occurring in targets with ages close to the disk dispersal time suggest that the end of accretion phase is reached in diverse ways., Comment: 13 pages, 3 figures. Accepted for publication in The Astrophysical Journal

We analyze 3 epochs of ultraviolet (UV), optical and near-infrared (NIR) observations of the Taurus transitional disk GM Aur using the Hubble Space Telescope Imaging Spectrograph (STIS) and the Infrared Telescope Facility SpeX spectrograph. Observations were separated by one week and 3 months in order to study variability over multiple timescales. We calculate accretion rates for each epoch of observations using the STIS spectra and find that those separated by one week had similar accretion rates (~1E-8 solar masses/yr) while the epoch obtained 3 months later had a substantially lower accretion rate (~4E-9 solar masses/yr). We find that the decline in accretion rate is caused by lower densities of material in the accretion flows, as opposed to a lower surface coverage of the accretion columns. During the low accretion rate epoch we also observe lower fluxes at both far UV (FUV) and IR wavelengths, which trace molecular gas and dust in the disk, respectively. We find that this can be explained by a lower dust and gas mass in the inner disk. We attribute the observed variability to inhomogeneities in the inner disk, near the corotation radius, where gas and dust may co-exist near the footprints of the magnetospheric flows. These FUV--NIR data offer a new perspective on the structure of the inner disk, the stellar magnetosphere, and their interaction., Comment: 22 pages, 5 figures, Accepted to ApJ