AKARI IRC NIR Low-resolution Spectral Catalog of Diffuse Sky Patches (ISAS/JAXA, 2013) ================================================================================ Low-Resolution Spectrum of the Zodiacal Light with AKARI InfraRed Camera Tsumura, K., et al. PASJ in press =2013PASJ...65..119K ================================================================================ ADC_Keywords: Interstellar medium ; Space observations ; Spectra, infrared ; Zodiacal regions Mission_Name: AKARI Keywords: catalogs - infrared: solar system - interplanetary medium - methods: data analysis - solar system: general Description: This catalog contains the 278 low-resolution (R~20) near-infrared (1.8-5.3 micron) spectra of diffuse sky covering a wide range of galactic and ecliptic latitudes with the Infrared Camera (IRC) on board AKARI before the exhaustion of liquid-helium (from September 2006 to May 2007). Advanced reduction methods specialized for the slit spectroscopy of diffuse sky spectra are developed for constructing this spectral catalog. Filter wheel of the IRC instrument has dark position to measure the dark current, and uncertainty due to dark current subtraction is estimated to be < 3 nW/m2/sr at 2 micron (Tsumura & Wada 2011). Point sources brighter than mK(Vega)=19 were detected on the slit and masked for deriving the diffuse spectrum. It was confirmed that the brightness due to unresolved galactic stars under this detection limit is negligible (< 0.5% of the sky brightness at 2.2 micron) by a Milky Way star count model (TRILEGAL; Girardi et al. 2005). Cumulative brightness contributed by unresolved galaxies can be estimated by the deep galaxy counts, being < 4 nW/m2/sr at K band in the case of limiting magnitude of mK=19 (Keenan et al. 2010). File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe.txt 80 . This file list.txt 46 278 Source list (1) spectrum/* 30 278 NIR spectra of diffuse radiation (2) plot/* - 278 Images of spectral plot (3) image/* - 278 Spectral images (4) -------------------------------------------------------------------------------- Note (1): Target IDs, observation date, and positions in equatorial coordinate system (RA, Dec) are summarized for all spectra. Note (2): Spectral data containing 1.8-5.3 micron are provided in text file; the name of each file is represented by a combination of target ID and sub-ID (e.g., AKARI_IRC_1100131_01.txt). Each file includes wavelength, surface brightness, statistical uncertainty, and calibration uncertainty. Note (3): Images of spectral plot for a visualization. Error bars included both statistical uncertainty and calibration uncertainty. Note (4): Spectral images in FITS format. Dark current subtracted, flat field corrected, and bad pixel masked images are provided. -------------------------------------------------------------------------------- See also: Low-Resolution Spectrum of the Diffuse Galactic Light and 3.3 um PAH emission with AKARI InfraRed Camera (Tsumura et al. 2013b) Low-Resolution Spectrum of the Extragalactic Background Light with AKARI InfraRed Camera (Tsumura et al. 2013c) Byte-by-byte Description of file: list.txt -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 10 A10 --- ID Target ID.sub-ID 12- 21 A10 --- date Observation date (5) 23- 30 A8 --- time Observation time (5) 32- 38 F7.3 deg RA Right Ascension (J2000) (6) 40- 46 F7.3 deg Dec Declination (J2000) (6) -------------------------------------------------------------------------------- Note (5): Obtained from header information in the original FITS file. Note (6): Calculated coordinate at the center position of the Ns slit referring to the header information in the original FITS file. -------------------------------------------------------------------------------- Byte-by-byte Description of file: spectrum/* -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 5 F5.3 micron Lambda Wavelength in micron 7- 14 F8.3 nW/m2/sr Ir Observed brightness (7) 16- 22 F7.3 nW/m2/sr e_Ir Statistical uncertainty (7) 24- 30 F7.3 nW/m2/sr E_Ir Calibration uncertainty (7) -------------------------------------------------------------------------------- Note (7): Unavailable data points are represented by NaN. -------------------------------------------------------------------------------- History: * 25-Jun-2013: Original version Author: Tsumura Kohji, tsumura(at)ir.isas.jaxa.jp ================================================================================ (End) Tsumura Kohji [ISAS/JAXA] 25-Jun-2013