Observing and Data Reduction Drift Scans with Radio Telescope Ground-based Near – IR Spectroscopy Airborne sub-mm imaging

Galactic HI Survey: Orion and High-Velocity Clouds Map HI (neutral hydrogen) at 21cm (1420MHz) Telescope: 4m radio dish at Cornell University Observing: Drift Scans at different declinations (24hrs each)

Data Acquisition Telescope beam is 3° on the sky => Drift scans every 3° Data averaged for 1min i.e. 0.25° Spectral resolution 10kHz i.e. 2km/s Reduction: Remove telescope response and gain variation Flux calibration using nearby wall

Results Left: Passage through the Orion Molecular Cloud and Galactic Plane for one drift scan Right: All Orion drift scans as seen on the sky.

Near IR Spectra of Herbig Ae/Be Stars Measure gas emission from the hot environment of young, massive, hot stars. Telescope: Mt. Palomar 5m Hale Telescope. PHARO medium resolution spectrometer. Data Acquisition: Chopped observations Calibration stars for flux reference and atmospheric correction

Data Reduction

Results Br gamma line indicates accretion onto the star. Numerical modeling of CO emission shows the presence of a rotating disk of hot gas.

Polarized Observations of Starforming Regions Measure polarization of Sub-mm emission SOFIA telescope HAWC instrument 5 Bands 45-240μm Cryogenically cooled

Observing Techniques Problem: Fast fluctuations in sky and instrument background Chop: Fast secondary mirror movement Removes fast background fluctuations Nod: Telescope movement Removes background gradients Dither: Repeat image with small offset Removes bad pixels Raw Image Chop Subtracted Nod Subtracted

4-position dither sequence Observing Modes NMC/C2N - Chop-Nod-Dither-Pol Chopping during ABBA nod sequence with 4 HWP positions (Left) Repeat this pattern for each 4 dither position (Right) ABBA ABBA ABBA ABBA 4-position dither sequence SCTT, 2017 Jan. 18 HAWC+ Commissioning

Orion Molecular Cloud Results HAWC map at right shows: HAWC Polarization vectors (black) from 6-position polarimetry mosaic (2 hours elapsed time) scan map shown in color scale (2 minutes) Magnetic field vectors from KAO / Stokes (white) Polarization vectors are assigned constant length to show direction of magnetic field. SCTT, 2017 Jan. 18 HAWC+ Commissioning