ILRS: IRAS low resolution spectra

Table name:     ilrs
Records:        
Version:
Spectral Band:  infrared
Kind of Object: 
Mode:           spectra
PreView:	yes
Coordinates:

Description

The IRAS survey instrumentation included a low-resolution spectrometer which covererd the wavelengths between 8 and 22 microns. The spectrometer operated during the entire survey, providing spectra of the brighter point sources. Because the survey function required a passive instrument, a slitless design was selected. This design is equivalent to an objective prism spectrograph, oriented in such way that the dispersion was aligned with the scan direction. Obvious penalties of this design are a degraded resolution for extended objects, sensitivity to spatial confusion, and short integration times. Two overlapping wavelength range were scanned simultaneously, one extending from 7.7 to 13.4 microns and the other from 11.0 to 22.6 microns. The scan length was nominally 6 minutes but internal misalignment obscured the extreme low end of the short wavelength range.

Fields

Name		Type	Meaning

csadc_id	I	Order number           
name		A	Source name      
ra_h		I	ra 1950 hrs    
ra_m		I	Ra 1950 min
ra_s		I	Ra 1950 deci-sec
dec_d		I	Dec 1950
dec_m		I	Dec 1950
dec_s		I	Dec 1950
flux1		F	Averaged non-color corrected flux densities(12)
flux2		F	" (25)
flux3		F	" (60)
flux4		F	" (100)
nspect		I	Number of observed spectra
nacc1		I	Number of accepted spectra(8-13)
nacc2		I	" (11-22)
lrsc1		I	Characterization of the spectrum(8-13)
lrsc2		I	" (11-22)
spq1		I	Quality of the spectrum(8-13)
spq2		I	" (11-22)
var		I	Percent of variability likelihood
nid		I	Number of associations
idtype			I	Type of assocoation
base1		I	Average of outer 20 samples of spectra
base2		I	The four base have to be scaled by SCALE
base3		I
base4		I
noise1		I	RMS noise by sample
noise2		I	Have to be scaled by SCALE
file_name	C	Spectrum file name
snr1		FG	Signal-to-noise ratio.
snr2		FG 
asym1		FG	Relative baseline asymmetry
asym2		FG  
sratio		FG	Ratio of integrated LRS flux to 12 micron flux
scale		C	Scale factor for all flux densities
c6025		C	Log(f60/f25)
c2512		C	Log(f25/f12)

ILRS: IRAS low resolution spectra

Contents

Description

Fields