Good UNM Telescopes and the Evil Atmosphere John McGraw

A Talk in the Universe of Good and Evil The Obscure Universe The Obscure Universe The Good – Fundamental new capability to understand the universe The Good – Fundamental new capability to understand the universe Why we want excellent ground-based telescopes Why we want excellent ground-based telescopes UNM Initiatives in Ground-based Astronomy UNM Initiatives in Ground-based Astronomy The Evil – The Earth’s atmosphere interferes with ground-based optical/IR observations in a number of ways The Evil – The Earth’s atmosphere interferes with ground-based optical/IR observations in a number of ways

The Obscure Universe Two causes of obscuration: Two causes of obscuration: Physical obscuration – dust! Physical obscuration – dust! Inability to observe – observational blindness. Inability to observe – observational blindness. Simultaneous optical/infrared time-resolved synoptic observations Simultaneous optical/infrared time-resolved synoptic observations

The Obscure Universe Discovery of Quasars Discovery of Quasars Quasar Lensing Quasar Lensing AGN Reverberation AGN Reverberation

The Obscure Universe The Nature of Quasars The Nature of Quasars

The Obscure Universe The “Standard Model” The “Standard Model” Accretion disc scale ~ 1 pc Accretion disc scale ~ 1 pc

The Obscure Universe AGN phenomenon is ubiquitous AGN phenomenon is ubiquitous Milky Way? Milky Way? All galaxies? All galaxies? Evolution? Evolution?

The Obscure Universe Mapping: Model, Orientation, Time History Mapping: Model, Orientation, Time History Light travel timescale ~ 3 years Light travel timescale ~ 3 years Dynamical timescale ~ r/V ~ 10 – 100 years Dynamical timescale ~ r/V ~ 10 – 100 years

The Obscure Universe The outsider’s view of gravitational lensing: The outsider’s view of gravitational lensing:

The Obscure Universe Geometry of Different Optical paths Geometry of Different Optical paths Source geometry Source geometry Lens geometry Lens geometry Source dust chemistry Source dust chemistry Well-sampled light curves Well-sampled light curves Optical path length measurement Optical path length measurement Effects of microlensing Effects of microlensing Dust in lenses Dust in lenses

The Obscure Universe Luminosity variability Luminosity variability Days to years Days to years Intrinsic variability Intrinsic variability Optical path length Optical path length Microlensing Microlensing Colley et al Colley et al. 2002

The Obscure Universe AGN Reverberation AGN Reverberation Mapping the scale, structure, and time-dependent structure changes in the environs of massive black holes Mapping the scale, structure, and time-dependent structure changes in the environs of massive black holes Testing the standard model of AGNs Testing the standard model of AGNs Examples: N1275, N7742 Examples: N1275, N7742

The Obscure Universe CTI CTI 1.8-m, f/2.2 meridian transit telescope 1.8-m, f/2.2 meridian transit telescope Images formed on multiple detectors operated in TDI mode Images formed on multiple detectors operated in TDI mode no moving parts no moving parts multiple colors each night multiple colors each night Fully automated operation Fully automated operation Photometric imaging over 1 - 2° FOV Photometric imaging over 1 - 2° FOV surveys ~120° 2 each night surveys ~120° 2 each night V  21.7 (S/N) > 5 nightly detection limit V  21.7 (S/N) > 5 nightly detection limit

The Obscure Universe Quasars Quasars 1° wide strip, α = 8 hours (NGC)  120° ² 1° wide strip, α = 8 hours (NGC)  120° ² 25 quasars/° ² to B = 21  3000 quasars 25 quasars/° ² to B = 21  3000 quasars Conservatism: 2° FOV, tilt to cover 10°, B fainter than 22 at S/N = 10, 2df data  all quasars Conservatism: 2° FOV, tilt to cover 10°, B fainter than 22 at S/N = 10, 2df data  all quasars Galaxies (same geometry, B = 19.7) Galaxies (same geometry, B = 19.7)  galaxies  galaxies SNe (same geometry, B = 21 point source) SNe (same geometry, B = 21 point source)  100 ~ SNe/year  100 ~ SNe/year

The Obscure Universe A UNM/UT collaboration can address many fundamental questions about the Obscure Universe. A UNM/UT collaboration can address many fundamental questions about the Obscure Universe. First year of five funded by AFRL First year of five funded by AFRL

Extinction, Refraction and Turbulence From Earth’s Atmosphere The atmosphere is a turbulent, absorbing, refractive medium that must be considered part of the optical system of any telescope. The atmosphere is a turbulent, absorbing, refractive medium that must be considered part of the optical system of any telescope. System design trade- offs: perhaps not too bad! System design trade- offs: perhaps not too bad!

Effects of Earth’s Atmosphere Three layers in the Earth’s atmosphere contribute to turbulence Three layers in the Earth’s atmosphere contribute to turbulence Surface layer Planetary boundary layer Upper atmosphere We can do something about the surface layer! We can do something about the surface layer!

Effects of Earth’s Atmosphere Refractive Index Structure Constant Refractive Index Structure Constant Where: Where: P(h) is pressure in millibars T(h) is temperature in Kelvin h is height in meters r is sensor separation in meters p is position at h separated by r

Effects of Earth’s Atmosphere Microthermal testing Microthermal testing 1-m separation Probes spaced in altitude 250 Hz digital sampling

Effects of Earth’s Atmosphere Microthermal measurements Microthermal measurements Sunrise neutral event Convective/radiative transport

Effects of Earth’s Atmosphere Surface Layer Atmospheric Turbulence Differential Image Motion Monitor Surface Layer Atmospheric Turbulence Differential Image Motion Monitor SLAT-DIMM Sources matched to sub-apertures Sources matched to sub-apertures DIMM technique Doesn’t assume atmospheric model Provisional patent in progress Provisional patent in progress

Effects of Earth’s Atmosphere LIDAR Saves Astronomy LIDAR Saves Astronomy Small, inexpensive lidar to monitor atmospheric transparency in real-time “Engineering data stream” Multiple use modes NSF proposal – Georgia Tech

Effects of Earth’s Atmosphere Real-time pupil curvature measurements Real-time pupil curvature measurements Real-time image PSF measurements Real-time image PSF measurements Pupil phase reconstruction? Pupil phase reconstruction?

Our Goals Site selection for CTI Site selection for CTI Help optimize HET Help optimize HET Transparency monitor (lidar) at CTI Transparency monitor (lidar) at CTI Real-time image reconstruction Real-time image reconstruction Access to telescopes for UNM Access to telescopes for UNM Investigate the Obscure Universe Investigate the Obscure Universe