DAZLE Calculations and Simulations

Fraser Clarke

  • S:N Calculator
  • SPIE Plots
  • Other Pages
  • Useful documents
  • Fabry-Perot Information
  • Telescope Information
  • Near-IR sky
  • DAZLE sensitivity calculations
  • Notes

  • The majority of programs here are written in C and rely heavily on the CPGPLOT library, and my own LIBADA library. You can compile programs by linking to the libraries in my home directory, here are some detailed instructions.
  • All the plots in this page are given as gzip'd postscript files
  • Unless otherwise stated, the cosmology is assumed to be Lambda-CDM (OM=0.3 OL=0.7 H0=65km/s/Mpc)

    Other Pages

  • Internal DAZLE page.
  • Public DAZLE page.
  • Rob Priddey's feasibility calculations.

    Useful documentation

  • JBH's paper on definitions of spectral resolution

    Fabry-Perot Information

    The proposal quotes a Finesse of 50. This corresponds to reflectivities (each surface equal) of;
    Amplitude = 0.969
    Intensity = 0.939
    (intensity = amplitude^2).

    If the Finesse was to be 100, that would give reflectivities of;
    Amplitude = 0.984
    Intensity = 0.969

    F-P Code

  • fp.c : Plots the transmission curve of a Fabry-Perot interferometer.(25/01/2000)
  • sepcalc.c : Calculates the plate seperation and order required to observe a given wavelength with a given bandpass (finds closest bandpass possible). (25/01/2000)

    Telescope Information

    Telescope Primary Dia. Cass Hole Collecting Area Focus Image Scale
    Gemini 8.1m 1.18m 37.59m2 ?? ??
    Magellan 6.5m 1.25m 21.55m2 ?? ??

    Near IR sky background

    NIR OH line lists

  • Merged line list from 0.9-1.4 microns. This is the line list used for most of the calculations.
  • The lines used by COHSI (and now CIRPASS).
  • A list of lines that are surpressed by CIRPASS. (Same as above, but in a nicer form).
  • Near IR (0.9-5µ m) sky background from Gemini page.
  • Keck/HIRES sky line atlas. From 5000-10500 angstroms, but doesn't have fluxes (I don't think).

    NIR sky code

  • plotskylines.c : Plots skylines from a default (or specified) linelist. (22/02/2000)


  • The position and relative strength of emission lines used in calculations (Flux in photons/s/m^2/arcsec^2).
  • Estimate of background contribution from emission lines seen by DAZLE over a its range of wavelengths (0.9-1.4 microns).

    DAZLE sensitivity calculations

    S:N Spectra - S:N obtained with a 10,000s exposure on Gemini.
  • Lyman-alpha with SFR=1Msol/yr. Resolution; 500, 1000, 2000, 4000
  • Aminated GIF showing the effect of changing the spectral resolution.
    Detectabiliy Spectra - SFR rate that gives S:N=5 in a 10,000s exposure on Gemini.
  • Lyman-alpha detected at S:N of 5. Resolution; 500, 1000, 2000, 4000

  • Comparison between DAZLE, gaussian and top-hat filters. I've made a close-up version that exagerates the differences.

    Last Modified: 22/2/2000
    Fraser Clarke (fclarke@ast.cam.ac.uk).