A cryogenic achromatic half-wave plate (HWP) for submillimetre astronomical polarimetry has been designed, manufactured, tested and deployed in the Balloon-borne Large-Aperture Submillimeter Telescope for Polarimetry (BLASTPol). The design is based on the five-slab Pancharatnam recipe and it works in the wavelength range 200-600 μm, making it the

Star-forming regions that are visible at 3.6 μm and Hα but not in the u, g, r, i, z bands of the Sloan Digital Sky Survey are measured in five nearby spiral galaxies to find extinctions averaging ~3.8 mag and stellar masses averaging ~5 × 104 M ☉. These regions are apparently young star complexes embedded in dark filamentary shock fronts connected

SDSS-III's newest release is Data Release 10 (DR10). DR10 contains the first spectra of the APO Galactic Evolution Experiment (APOGEE). APOGEE is the first high-resolution (R ~ 22,500), high signal-to-noise ratio (S/N >= 100 per resolution element), H-band (1.51 - 1.70 um) survey of all Galactic stellar populations (bulge, bar, disks, halo) with a

We report and study the outburst of a new transient X-ray binary (XRB) in Terzan 5, the third detected in this globular cluster, Swift J174805.3-244637 or Terzan 5 X-3. We find clear spectral hardening in Swift/XRT data during the outburst rise to the hard state, thanks to our early coverage (starting at LX ~ 4 × 1034 erg s–1) of the outburst. This

High spectral resolution spectroscopy has proved to be very useful for the advancement of chemical abundances studies in photoionized nebulae, such as H II regions and planetary nebulae (PNe). Classical analyses make use of the intensity of bright collisionally excited lines (CELs), which have a strong dependence on the electron temperature and

The SDSS-III APOGEE experiment is obtaining high-resolution near-IR spectra to provide measurements of stellar parameters and chemical abundances for stars in many different regions of the Galaxy. I will discuss initial results on the spatial variations of abundances derived from APOGEE data to date. In particular, I focus on mean metallicities in