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ASTR 3520 Observations & Instrumentation II: Spectroscopy. Lecture 1 Introduction. Overview John Bally C323A Duane 492 5786 [email protected] [email protected]

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slide1

ASTR 3520

Observations & Instrumentation II:

Spectroscopy

Lecture 1

Introduction

slide2

Overview

slide3

Organization

  • Review course structure, content, and Syllabus
  • Observing Projects: Stellar, nebular spectroscopy, semester projects, labs, homework.
  • Apache Point Observatory Field Trip:
  • - 5 - 6 days/ 4 - 5 nights
  • - Covered by Course Fees
  • - VLA, NSO, APO
  • - Last week of Oct. (depends on TAC)
  • Observing Proposals for Semester project due end of Sept.
  • 24” Observing Groups 5 groups / 3 to 4 each.
  • - Each group must have at last 1 experienced observer
  • Start spectrograph overview (once-over lightly)
slide4

Spectroscopy: Astronomy => Astrophysics

  • Light as a wave phenomenon: = c
  • Geometrical optics => wave optics
  • Diffraction
  •  ~  / D
  • Interference:
  • n = D sin n = 1,2,3,…
  • Deep insights into the nature of atoms, molecules:
  • Discrete wavelengths => Discrete energy levels
  • Electrons stable only in certain orbits.
  • Interference of electron waves!
  •  = h / p = h / mv :de Broglie waves
  • All matter has wave-like behavior on sufficiently
  • small scale!
slide5

Spectrograph

Focal Plane

collimator

camera

detector

Dispersing element

Slit

Telescope

Spectrograph

slide6

SBO Spectrograph overview

  • Slit & Decker:
  • Restrict incoming light
  • Spatial direction vs. Spectral direction
  • Collimator & Camera:
  • Transfer image of slit onto detector.
  • Grating:
  • Disperse light: dispersion => spectral resolution
  • What determines spectral resolution & coverage?
  • - Slit-width
  • - Grating properties: Ngroves , order number
  • - Camera / collimator magnification (focal length ratio)
  • - Detector pixel size and number of pixels.
slide7

Types of Spectroscopy

  • Electromagnetic Waves: Emission, absorption
  • Visual, near-IR., FIR, Radio, UV/X-ray, gamma-ray
  • - Solids, liquids, gasses, plasmas
  • - Emission, absorption
  • - Spectral line, molecular bands, continua:
  • - Thermal (~LTE, blackbody, grey-body):
  • - Non-thermal (masers, synchrotron, …)
  • - Electronic, vibrational, rotational transitions.
  • - Effects of B (Zeeman), E ( Stark), motion (Doppler),
  • pressure (collisions), natural life-time (line widths)
  • - Radiative Transfer (optical depth)
  • Other types (not covered in this course):
  • NMR
  • Raman
  • Phosprescence / Fluorecence
  • Astro-particle
slide8

Review of Some Basics

  • c = n x l
  • Angular resolution: q = 1.22 l / D radians
  • 206,265” in a radian
  • E = h n
  • F = L / 4 p d2
  • AZ, El, RA, Dec, Ecliptic, Galactic
  • Siderial time, Hour Angle
  • G = 6.67 x 10-8 (c.g.s)
  • c = 3 x 1010 cm/sec,
  • k = 1.38 x 10-16
  • h = 6.626 x 10-27
  • mH ~ mproton = 1.67 x 10-24 grams
  • me = 0.91 x 10-27 grams
  • eV = 1.602 x 10-12 erg
  • Luminosity of Sun = 4 x 1033 erg/sec
  • Mass of the Sun= 2 x 1033 grams
slide9

The Physics of EM Radiation

  • Light: l, n
  • - l n = c = 2.998 x 1010 cm/s (in vacuum)
  • - E = h n Photon energy (erg)
  • 1 erg sec-1 = 10-7 Watt
  • h = 6.626 x 10-27 (c.g.s)
  • 1 eV = 1.602 x 10-12 erg
  • - p = E / c = h / l Photon momentum
  • - l = h / p = h / mv deBroglie wavelength
  • Planck Function: B(T)
  • Emission, absorption, continua
  • Discrete energy levels: Hydrogen
slide10

Refraction:

Snell’s Law: n1 sin(d1) = n2 sin(d2)

d1

n1

n1 = refractive index in region 1

n2 = refractive index in region 2

n = c / v = lvacuum / lmedium

d2

n2

slide14

L

d

Diffraction:

Light spreads asq = l / d

In the `far field’ given byL = d2 / l

slide15

2 slit interference

Constructive

Destructive

slide16

2 slit interference

Anti-reflection coating

slide20

Fermat’s Principle: d(optical path length) = 0

Diffraction grating:

order #

wavelength

diffraction angle

groove spacing

incidence angle

slide22

CCD Imaging Review

  • Review CCD basics
  • - How CCDs work
  • - CCD properties
  • Dark, flat, and bias frames
  • Image-scales
  • - focal length, pixel-scale, FOV
  • Review photometry basics
  • - The magnitude system
  • - Calibration
  • - Atmospheric effects; Air mass, color terms
slide23

Subaru 8m (Mauna Kea): Suprime Prime Focus CCD Mosaic

8192 x 8192 pixels using SITe chips (15 mm pixels)

slide24

Typical

Raw image

With a CCD

Cosmic rays

Bad pixels

stars

slide25

CCDs (Charge-Coupled Device)

  • Properties
  • - Quantum efficiency (QE):
  • => 90%
  • - Gain:
  • G = e- /ADU
  • - Dark current:
  • 1 e- / hr to 103e- /sec
  • thermal emission: => Cool to –20 to –150 C
  • - Read Noise:
  • amplifier read-out uncertainty
  • 3 e- to 100 e- per read
  • - Spatial uniformity:
  • Bad pixels, columns: ~ << 1%
  • gain & QE variations

Ee = hn - E0

slide26

CCDs

  • Properties
  • - Cosmic Rays:
  • 5 to > 103 e- produced by each charged particle
  • usually effects 1 or few pixels.
  • non-gaussian charge distribution
  • (different from stellar image or PSF)
  • - Well depth:
  • 5 x 104 to 106 e-
  • - Pixel size:
  • 6 mm to 30 mm
  • - Array size:
  • 512 x 512 to 4096 x 4096
slide28

Dark current:

=> cooling

slide29

MOSAIC CCD

On KPNO 0.9m

Vacuum Dewar

LN2 (77K)

Controller

Filters & slider

slide30

5

10

10

0

Charge Transfer

V

0

10

0

5

5

slide35

CCD Corrections/Calibrations

  • Read noise: bias frames
  • - 0 second exposure
  • Dark frames:
  • - Same duration as science exposure with shutter closed
  • Flat fields:
  • - Dome flats
  • - Twilight flats
  • - Super-sky flats
  • Standard stars
  • - At several air-masses
  • A = sec (z) = 1 / cos(z)

z

slide36

CCD Corrections/Calibrations

  • Types of image combinations:
  • IRAF task: imarith image1 (+,-,*,/) image2 output
  • imcombine @list_in output
  • - Average: 1/N S I(n)
  • - Mode: Most common data value
  • - Median: Value in middle of range
  • good for rejection of outliers (e.g CRs)
  • Combine (median) 3,5,7,….. An odd #
  • - bias frames
  • - flat frames
slide37

CCD Corrections/Calibrations

  • Reduction:
  • I(raw) - median(bias)
  • I(reduced) =
  • norm [median(Flat – bias)]
  • Note: Bias can be a Dark if hot pixels /or dark current is large
slide38

Flat Field Example

star

cosmic ray

Hot pixels

star

Bias or

dark level

Raw science frame

star

cosmic ray

star

Dark subtracted frame

slide39

Flat Field Example

star

cosmic ray

star

cosmic ray

Flat frame

slide40

Flat Field Example

cosmic ray

Flat frame

1

Normalized, dark subtracted, median of > 3 flat frames

slide41

Flat Field Example

cosmic ray

star

Science frame

1

Normalized flat frame

star

star

Reduced science frame

slide42

Photometry Basics:

  • Vega magnitudes:
  • m(l) = -2.5 log [F(l) / FVega(l)]
  • F(l) = Counts on source
  • FVega(l) = Counts on Vega
  • A = sec (z) = 1 / cos(z)

z

slide43

Type of Spectra

  • Continuum:
  • - Blackbody: Bn(T)
  • - free-free, free-bound
  • - Non-thermal: Synchrotron radiation
  • - Compton scattering
  • Line & Band
  • E dipole, B diplole, E quadrupole
  • fine structure, hyperfine structure
  • - electronic transitions
  • - vibrational transitions
  • - rotational transition
slide44

Types of Spectra:

Hot,

Opaque

media

Nebulae

Stars

slide45

The Planck Function: Black-body radiation

(erg s-1 cm-2 Hz-1 2 p sr-1)

Wien:

B(n,T) = (2 p hn3 / c2) e-hn/kT

Rayleigh-Jeans:

B(n,T) = 2kT/l2

slide48

Spectrum of Hydrogen (& H-like ions)

Ionization (n to infinity):

E = 13.6 eV

Transitions:

E = hn = Eu – El

Ionizationat

E = 13.6 eV or less than

l = 912 Angstroms

a

b

g

Balmer

  • = R [ 1/nl2 – 1 /nu2]

R = 3.288 x 1015 Hz

b

a

Lyman

slide49

Bohr model:

Allowed orbits

mvr = nh /2p

Coulomb Force:

Ze2 / r2 = mv2/r

Thus,(eliminate v)

r = Ze2 / mv2 = n2h2 / 4 p2 Ze2 m

Energy E = - (1/2) Ze2 / r = - 2 p2 Z2e4m/ n2h2

slide54

Outline & Goals: Tues, 18 Sept

  • Summary of Kitt Peak Run &Heildelberg
  • Review Spectrum of Hydrogen
  • Spectroscopic `terms’ & terminology
  • (Ch 2, 3; HW #2)
  • Review Transitions (Ch 3): Einstein
  • A, B. Collisional and radiative
  • excitation
  • Spectral line formation & Radiative
  • Transfer basics
slide55

Bohr model:

Allowed orbits

mvr = nh /2p

Coulomb Force:

Ze2 / r2 = mv2/r

Thus,

r = Ze2 / mv2 = n2h2 / 4 p2 Ze2 m

Energy E = - (1/2) Ze2 / r = - 2 p2 Z2e4m/ n2h2

slide56

Spectrum of Hydrogen (& H-like ions)

Ionization (n to infinity):

E = 13.6 eV

Transitions:

E = hn = Eu – El

Ionizationat

E = 13.6 eV or less than

l = 912 Angstroms

a

b

g

Balmer

  • = R [ 1/nl2 – 1 /nu2]

R = 3.288 x 1015 Hz

b

a

Lyman

slide57

Ionization cross-section or hydrogen

13.6 eV = 912 Angstroms

10-18

Lyman lines

Balmer lines

n-3

Cross-section (cm2)

Wavelength (1 / photon energy)

slide58

Atomic Structure

  • Refinements to Bohr:
  • Elliptical e-orbits
  • Integral of P in r and q = lh l = 0,1,2, …,n-1
  • Relativistic effects => l makes small
  • correction to E-levels
  • Space quantization: Orientation of orbits
  • m
  • Electron spin
  • Pauli: No 2 e- in same state.
slide59

Atomic Structure

  • Atomic quantum numbers:
  • n, l, m, s - completely specify state, E
  • n = 1, 2, 3, 4 ….
  • shell = K L M N ….
  • max ne = 2 8 ….
  • l = 0 1 2 3 4 ….
  • s p d f g ….
  • Selection rules:
slide60

Atomic Structure

  • Refinements to Bohr: n
  • Elliptical e-orbits: k
  • Space quantization: Orientation of orbits
  • w.r.t. magnetic field: m
  • Electron spin: s
  • Pauli: Ferminons:
  • No 2 e- in same state: [n,k,m,s]
  • Shroedinger Wave function:
  • n => principle quantum number (radial)
  • l => orbital angular momentum 0, 1, … n
  • m => magnetic sublevels (degenerate if B=0)
  • s => electron spid +/- 1/2
slide61

Atomic Structure

  • Multi-electron atoms/ions
  • Atomic quantum numbers: s = +/- 1/2
  • n, l, m, s - completely specify state, E
  • l = 0, 1, …, (n-1) m = 0, +/- 1, +/- 2, …, +/- l
  • n = 1, 2, 3, 4 ….
  • shell = K L M N ….
  • l = 0 0, 1 0,1,2 0,1,2,3
  • m = 0 0; -1,0,1 0;-2,-1,0,1,2 0;-3,-2,-1,0,1,2,3 max ne = 2 2+6 = 8 2+8+10 = 20 … (s = +/- 1/2)
  • max l = 0 1 2 3 4
  • s s,p s,p,d s,p,d,e
  • Selection rules: Dl = +/- 1
slide62

n

1

2

3

4

slide65

Hydrogen Ha fine structure

  • Review Transitions (Ch 3): Einstein
  • A, B. Collisional and radiative
  • excitation
  • Spectral line formation & Radiative
  • Transfer basics
slide67

Hydrogen energy levels showing fine structure

2s+1

Fine structure const.:

 = e2/ hc = 1/137

Fine structure:

E / E ~ 4 ~ 5x10-5 eV

Spin / orbit (l * s)

3d 2D5/2

3p 2Po3/2

n=3

n=2

n=1

3d 2D3/2

3s 2S1/2

3p 2Po1/2

H

Ly

J=L+S

2p 2Po3/2

2p 2Po1/2

Hyperfine structure:

E ~ 6x10-6 eV

2s 2S1/2

Selection Rules:

l = 0, +/-1

j = 0, +/-1

even <=> odd

L = [l(l+1)]1/2 h/2

S = [s(s+1)]1/2 h/2

J = [J(J+1)]1/2 h/2

l = 0 l = 1 l = 2

S P D

1s 2S1/2

slide68

Einstein A & B coefficients: radiative processes

u

Aul

- Spontaneous decay

Bul

- Stimulated decay (prop to Flux)

Aul

Bul

Blu

Blu

- Absrorption (prop to Flux)

l

slide69

Ionization & Excitation

  • Radiation: Rr = s Irad
  • Collisions: Rc = n s <vthermal>

 = cross section

Vthermal ~ (3 kT / 2 m)1/2

Aul, Bul

Cul

Clu

Blu

Rate Equations:

slide70

Spectral Line Formation &

Radiative Transfer

  • Guidelines for 24” spectroscopy
  • Simple Models for Spectrum Formation
    • emission nebulae
    • absorption line features
    • continuum processes
  • Theory of Spectrum Formation
    • optically thin and optically thick spectra
    • stellar spectra
emission nebulae
Emission Nebulae
  • Atoms in nebulae are excited by:
    • Incident photons
    • Collisions (high temperature or density)
  • Excited atoms decay, emitting a photon of the characteristic energy (a spectral line)
  • If the atoms are ionized, then the nebula will emit free-bound radiation (i.e. Balmer continuum) as well as spectral lines
slide72

Ionization cross-section or hydrogen

13.6 eV = 912 Angstroms

10-18

Lyman lines

n-3

Cross-section (cm2)

Wavelength (1 / photon energy)

slide73

Emission Nebula

(photo-excited or photo-ionized)

optically thin nebula:

passes most wavelengths

Star emits continuum

- light at energy equal to an atomic transition is absorbed

- that light is then reemitted in a

random direction (some of it towards the observer)

- the nebula may be optically thick at these wavelengths

The only light directed towards

the observer is that which has

energy equal to the atomic

transitions in the nebula:

an emission spectrum

slide76

M82 – Subaru 8-m (Mauna Kea)

Emission line (Ha)

Absorption (dust, NaI, …)

continuum

emission (stars)

slide78

M82 – 21 cm HI (VLA)

M82

M81

NGC3077

slide79

M82 H

M82 radio (6 cm)

absorption features
Absorption Features
  • Continuum light is emitted from a star (or other source)
  • Intervening material absorbs light at wavelengths of atomic transitions, exciting those atoms
  • Excited atoms reemit light, but in a random direction (not towards observer)
slide83

Absorption Feature:

the observer sees all the

wavelengths except those

at the atomic transition energy

an absorption spectrum

Star emits continuum

- light at energy equal to an atomic

transition is absorbed

- that light is then reemitted in a

random direction

slide85

What Does an Absorption Spectrum Look Like in an Image?

Quasar 3C273

Deneb

It looks almost identical to the background object!

All the absorption is in a few lines, the continuum

is relatively unchanged.

slide86

Dark or Reflection Nebula:

optically thick nebula:

-observer can’t see background

object (i.e. star) because light

has been scattered away

- dark nebula

Star emits continuum

dust scatters light

optically thick nebula:

-observer sees cloud shining in

scattered light (a continuum)

-reflection nebula

continuum phenomena reflection and dark nebulae
Continuum Phenomena:Reflection and Dark Nebulae

reflection

  • Dust scatters incident light
  • Not a line process, scatters continuum

dark

dark

basic radiative transfer terms
Basic Radiative Transfer Terms

lMFP = mean free path (cm)

au = opacity (cm-1) – cross section per unit volume (aka absorptivity)

lMFP = 1/au

tu = optical depth (unitless)

optical depth
Optical Depth
  • Optical depth measures the attenuation of light
  • The light we see from an optically thick source was emitted at t approximately 1

tu = 1 at s = lMFP

radiative transfer
Radiative Transfer

What does the observer see?

-assume that the background

cloud is opaque (t1 >> 1)

-assume both clouds are uniform

T1

t1>> 1

T2

t2

This equation has two simple limits …

slide91
Optically Thick (tu >> 1)

many scatterings through the cloud

  • Optically Thin (tu << 1)
    • one or fewer scatterings through the cloud on average

contribution from

background cloud

contribution from

foreground cloud

since the foreground cloud is optically thick, all the contribution is from that cloud

stellar spectra
Stellar Spectra:
  • The spectrum of a star forms in its atmosphere
  • The temperature in the atmosphere is stratified
  • The emission at any temperature is a blackbody (for an optically thick source)
  • The opacity is a function of wavelength
slide93
At each wavelength, t=1 corresponds to a different depth in the atmosphere and thus a different temperature
  • The opacity in a line is much higher than in a continuum
  • In a line, we see to a very shallow depth in the atmosphere
slide95

Based upon the previous image, does temperature in the Sun increase or

decrease with height in the atmosphere?

Temperature decreases with height because the lines (which are formed higher up) are darker than the continuum and thus are emitted from a cooler region.

This allows us to probe the temperature of the sun as a function of depth.

slide96

Solar Spectrum Trace:

notice the different linewidths in different lines

and the strong Calcium H & K lines

Ca K

Ca H

solar limb darkening98
Solar Limb Darkening

At edge you only see down to a shallower depth (lower temperature) at t~1

At center you see down to a certain depth at t~1

terminology
Terminology
  • Surface brightness is synonymous with temperature

The continuum has a TB of 5,000K

The line has a TB of 10,000K

terminology radio astronomy
Terminology: Radio Astronomy
  • Radio astronomers often plot spectra as TB vs l
    • TB is a physical measurement
    • but only for thermal processes (that are optically thick)
  • Why is this terminology most appropriate for radio astronomy?
    • radio astronomy is well into the R-J tail
slide103

Summary & Goals: Oct 4

  • Discuss observing proposals
  • What we covered:
  • Review EM basics, atomic structure basics
  • Intro to gratings & spectrographs: Grating equation
  • Black-bodies. Fluxes, exposure time estimation
  • The H atom & its spectrum
  • Einstein A & B coefficients; radiative & collision rates
  • Radiative transfer & spectral line formation
  • To be covered by Field Trip:
  • Saha equation: ionization of atoms into successive stages of
  • ionization
  • Stellar classification basics
  • Nebula ionization & excitation: the roles of UV
  • Spectrograph design: optics, matching R, pixels, and seeing
  • Radio astronomy
slide104

Ionization Balance: (Saha formula)

Each element has an ionization potential for each

every electron: Roman numeral is number

of electrons lost + 1

Netural H = HI

Ionized H = HII

Molecular H = H2

HI – 13.6 eV

HeI – 24.58 eV, HeII – 54.416 eV

CI - 11.26 eV, CII – 25.14 eV, CIII – 47.89 eV, CIV – 64.49 eV,

CV – 392 eV, CVI – 490 eV

OI – 13.6 eV, OII – 35.11 eV, OIII – 54.9 eV

Ca XXI – 5,469 eV

slide105

Ionization stage

I

II

III

IV

V

Relative abundance

Temperature

slide106

Saha Formula

Partition function (# of states)

Ionization potential

Electron density

Next ionization stage density

Previous ionization stage density

slide116

Ionization Balance: Ionized nebulae

HII regions, planetary nebulae: UV

Supernova remnants: shocks

Ionization produced by:

- UV to X-ray radiation fields:

stars, white dwarves, neutron stars, accreting WDs, NS,

and black holes

- Collisions: Shock heated gas

Recombinations: Electrons re-combine with ions

Stromgren (photo-ionization equilibrium):HII regions

Q = (4 p/3) r3 ne2aB

Q = Lyman continuum luminosity (~1049 photons/sec for O7 star)

aB = 2.6 x 10-13 cm3 /sec (Recombination coeff. for H at 10,000 K)

slide117

Thor’s helmet:

NGC 2359

HD 56925

slide121

HH 131

Orion A:

- Outflows up to

30 pc long !

M42

HH34

HH 1/2

slide124

HH 46/47

HST 1997 - 1994

slide125

HH 46/47

HST 1997 - 1994

slide126

Stromgren radius of an HII region:

Lyman continuum luminosity of O, B stars:

O3: L(LyC) = 1.0 x 1050 photons s-1 T = 60,000 K

O5: L(LyC) = 4.7 x 1049 photons s-1 T = 48,000 K

O7: L(LyC) = 6.7 x 1048 photons s-1 T = 35,000 K

O9: L(LyC) = 1.7 x 1048 photons s-1 T = 32,000 K

B0: L(LyC) = 4.7 x 1047 photons s-1 T = 30,000 K

B3: L(LyC) = 4.7 x 1045 photons s-1 T = 20,000 K

n = 1000, O5 star:

L(Lyc) ~ n2 r3 aB => r ~ [L(LyC) / n2 aB]1/3

5.6 x 1018 (cm)

1.8 pc

slide127

Photo-ionization equilibrium

(in-class exercise)

Consider an O7 star that emits 1049 Lyman continuum

photons per second which is embedded in a uniform

density cloud with n(H) = 1 cm-3.

- What is the Stromgren radius?

- What is the mass that is ionized?

- How would these answers change if n(H) = 104 cm-3

slide128

HII (ionized nebulae) cooled and traced

  • by trace elements & ions
  • Many forbidden transitions have DE ~ 2 eV (visible)
  • long life-times, low decay rates (Einstein A coefficients)
  • Collision rate: Rcoll = n<sv>
  • n ~ 102 cm-3
  • s ~ 10-15cm-2 (for atoms. Depends on v for ions)
  • v ~ (kT / mm)1/2 (sound speed ~ 10 km/s for H
  • at 10,000 K)
  • R ~ 10-7 sec-1 (1 collision every 107 sec)
  • Collision rate ~ decay rate => each ion can radiate
  • Thousands of times before recombining => bright line
slide129

Some common transitions in ionized nebulae:

[SII] 6717/6731 A (density tracer)

[NII] 6748/6784 A

Ha 6563 A

[OI] 6300/6363 A

[OIII] 5007 A

[OII] 3729/3726 A

slide130

Long-slit:

Spectrum

of a planetary

nebula

slide132

Planetary nebula

M57 (Ring nebula)

Objective prism (slitless) spectra:

slide136

n-3

~2 eV

Why `forbidden’ emission lines are bright

13.6 eV

Ha

9.2 eV

Photo-ionization =>

recombination

Collisional

Excitation

<E >~3/2 kT = 1.3 eV @104 K

slide137

Measuring nebular density using [SII] lines

1.4

1.0

[S II] I(6717/6731)

0.6

101 102 103 104

Density (cm-3)

slide140

Three problems:

Star with a wind spherical cloud star in a pipe

slide141

Ionization Balance: (Saha formula)

Each element has an ionization potential for each

every electron: Roman numeral is number

of electrons lost + 1

Netural H = HI

Ionized H = HII

Molecular H = H2

HI – 13.6 eV

HeI – 24.58 eV, HeII – 54.416 eV

CI - 11.26 eV, CII – 25.14 eV, CIII – 47.89 eV, CIV – 64.49 eV,

CV – 392 eV, CVI – 490 eV

OI – 13.6 eV, OII – 35.11 eV, OIII – 54.9 eV

Ca XXI – 5,469 eV

slide142

Ionization stage

I

II

III

IV

V

Relative abundance

Temperature

slide143

Saha Formula

Partition function (# of states)

Ionization potential

Electron density

Next ionization stage density

Previous ionization stage density

slide146

Wolf-Rayet stars:

> 60 Solar mass, post-main sequence

WR 124

slide148

2006 APO Field Trip

  • What to Bring:
  • - Pack light (like carry-on on an airplane)
  • - Jacket, hat, gloves (prepare for cold near freezing)
  • - Flashlight
  • - Cash for food (supermarket + stops during drive)
  • - Personal items
  • Where:
  • - Meet at Circle at NW corner of Benson @ 9:00 AM Monday
  • 30 Oct (be early!)
  • Need two volunteers with sleeping bags for Mon night
  • (Socorro)
  • - Return Friday (3 Nov) in the evening.
slide149

2006 APO Field Trip

Itinerary:

- Monday: Drive from Boulder to Socorro, NM (9 - 10 hrs)

- Tuesday: Meet Debra Shepherd at NRAO ~ 8:30 AM

Drive to VLA site (1 hr)

Tour VLA

Return to Socorro - have lunch

Drive to APO (4 hrs) & shop for food

Settle in to dorm rooms / houses

Observe till 1:00 AM (If we are late, remote

observers will operate remotely from Boulder)

- Wed: PM tour of NSO (?) + cook dinner

Observe all night

- Thurs: Sleep during day / observe first half

- Friday: Rise at 8:00 AM, drive back (10 - 11 hrs)

slide150

Project / Observing Summary

Itinerary:

Tues (first half) M17 LBV, Ceph A DIS new high red

Hyades WDs (Audrey, Ward, Nate)

Wed (whole night) Comet Swan (Corey, Julia, Tedd)

Eyepiece on Moon etc.

Metallicity

QSO outflow (Max)

HL/XZ Tau (Alexi, Courtney, Carlee, Beau)

DIS new high red / eyepiece / DIS / SpiCam / eyepiece (dawn):

Orion, NGC1068, Saturn

thurs (first half) APOLLO laser

finish projects as needed.

slide154

Atacama Large Millimeter Array: Sajnantor Chile, ~ 64 12 meter dishes Baselines: 150 meter to 10 km

slide155

ALMA site: Sajnantor Chile,

Elevation ~ 5,000 meters!

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