Comparison of Photometric And Spectroscopic Redshifts

5. Comparison of Photometric And Spectroscopic Redshifts

6. The FIR emission Of dust is polarized At the level between A few and several % (Hildebrand, Dragovan & Novak 1984). SCUBA beam (850 mm) Atacama beam (350 mm) The Atacama Telescope bolometer camera’s large FOV and high angular resolution provide a powerful tool in measuring magnetic fields, by observing the polarization of FIR dust emission. NGC2024 Atacama FOV [Image: Mathews et al. 2002]

7. Flux (Jy) Heinrichsen et al.1998 Wavelength (m) Circumstellar Disks • Most PMS stars of < 3—4 solarm are thought to have circumstellar disks • Disks last a few Myr, until they dissipate • Planets form during that phase • Disks’ sizes are thought to vary widely, between a few 10’s and few 100 AU • Disks’ masses also vary widely, about on average a few % of the stellar mass • Disks’ temperatures are consistent with irradiation by the star, • hence they exhibit strong thermal gradients • Inner disk morphology can be studied via scattered radiation in the NIR • Understanding of disks’ physics requires measurements of dust mass, • which radiates in the FIR • Outer disk structure is tidally disrupted by the presence of planets go SED of Disk around Vega

8. Atacama at 200 mm SIRTF at 38 mm LMT at 1100 mm SOFIA at 38 mm

9. Atacama beam at 200 mm Scuba beam at 850 mm Vega e Eri .

10. SCUBA 5-sigma 10,000sec PWV 1.5mm JCMT Confusion Limit Atacama Confusion Limit Atacama 5-sigma 10,000sec PWV 0.3mm

11. LMT Confusion Limit LMT 5-sigma 10,000sec PWV 1.5mm

12. Atacama 5-sigma 10,000sec Atacama Confusion Limit

13. Atacama 5-sigma 10,000sec PWV 0.3mm Atacama Confusion Limit

14. Surface error budget (micron) and pointing Error (arcsec) for the LMT, ALMA and the Proposed Atacama FIR/submm Telescope Both LMT and ALMA telescope Will operate without dome/windscreen Protection. Their surface error Budgets are designed for operation In up to 10 m/s winds.