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

2. 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)

3. 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

4. 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.

5. 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

6. Data Reduction

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

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

9. 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

10. 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

11. 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