HDS Exposure Time Calculator

Input flux spectrum

magnitude:	Power law	Spectral index: (S_ν ~ ν^-α)
Redshift:	Blackbody	Temperature: K
	Template	(from the UVKLIB spectral library)

Instrument setting

Setup: ADC No ImRot Blue ImRot Red ImRot
For non-standard setups, use the grating with a central wavelength of A
(default selects the most appropriate grating for the wavelength range).

Messia: Messia4 Messia5
Binning: 1×1 2×1 2×2 2×4 4×1 4×4 (spatial × spectral)
Echelle grating angle: degrees. Detector rotation angle: degrees
Slit: Normal slit (width arcsecond) Image slicer (0''.3×5)
Seeing size: arcsecond

Exposure time: seconds.

Note1: Use HDS Echelle Format Simulator to check the detailed spectrum format with the desired instrument setting.

Note2: Since the template spectra cover a limited wavelength range, correct normalization of the spectrum may not be possible at high redshift.

Note3: The efficiency of Image Slicer is compared with the normal slit (0.3 arcsecond slit width) observation. If this value is presented in red, the order gap might be too small.

Akito Tajitsu, 20 October 2011
Chris Simpson, 4 January 2002