J/A+A/578/A8 Multi-resolution images of M33 (Boquien+, 2015)
Measuring star formation with resolved observations: the test case of M 33.
Boquien M., Calzetti D., Aalto S., Boselli A., Braine J., Buat V.,
Combes F., Israel F., Kramer C., Lord S., Relano M., Rosolowsky E.,
Stacey G., Tabatabaei F., van der Tak F., van der Werf P., Verley S.,
Xilouris M.
<Astron. Astrophys. 578, A8 (2015)>
=2015A&A...578A...8B 2015A&A...578A...8B
ADC_Keywords: Galaxies, nearby ; Photometry, infrared ; Ultraviolet
Keywords: galaxies: individual: M33 - galaxies: ISM - galaxies: star formation
Abstract:
We investigate the impact of spatial resolution on the measurement of
the star formation rate in the nearly galaxy M33. To do so we combine
different star formation rate estimators and examine their relative
variations from a scale of 8"/pixel (33pc/pixel) to 512"/pixel
(2084pc/pixel).
Description:
The FITS file contains maps of the flux in star formation tracing
bands, maps of the SFR, maps of the attenuation in star formation
tracing bands, and a map of the stellar mass of M33, each from a
resolution of 8"/pixel to 512"/pixel.
The FUV GALEX data from NGS were obtained directly from the GALEX
website through GALEXVIEW. The observation was carried out on 25
November 2003 for a total exposure time of 3334s.
Hα+[NII] observations were carried out in November 1995 on the
Burrel Schmidt telescope at Kitt Peak National Observatory.
The observations and the data processing are analysed in detail
in Hoopes & Walterbos (2000ApJ...541..597H 2000ApJ...541..597H).
The Spitzer IRAC 8um image sensitive to the emission of Polycyclic
Aromatic Hydrocarbons (PAH) and the MIPS 24um image sensitive to the
emission of Very Small Grains (VSG) were obtained from the NASA
Extragalactic Database and have been analysed by Hinz et al.
(2004ApJS..154..259H 2004ApJS..154..259H) and Verley et al. (2007A&A...476.1161V 2007A&A...476.1161V, Cat.
J/A+A/476/1161).
The PACS data at 70um and 100um, which are sensitive to the warm dust
heated by massive stars, come from two different programmes. The 100um
image was obtained in the context of the Herschel HerM33es open time
key project (Kramer et al., 2010A&A...518L..67K 2010A&A...518L..67K, observation ID
1342189079 and 1342189080). The observation was carried out in
parallel mode on 7 January 2010 for a duration of 6.3h. It consisted
in 2 orthogonal scans at a speed of 20"/s, with a leg length of 7'.
The 70um image was obtained as a follow-up open time cycle 2
programme (OT2mboquien4, observation ID 1342247408 and 1342247409).
M33 was scanned on 25 June 2012 at a speed of 20"/s in 2 orthogonal
directions over 50' with 5 repetitions of this scheme in order to
match the depth of the 100um image. The total duration of the
observation was 9.9h.
The cube, cube.fits files, contains 16 extensions:
* FUV
* HALPHA
* 8
* 24
* 70
* 100
* SFR_FUV
* SFR_HALPHA
* SFR_24
* SFR_70
* SFR_100
* SFRFUV24
* SFRHALPHA24
* A_FUV
* A_HALPHA
* MSTAR
Each extension of FITS file content 505 "versions".
For each extension , the FITS header indicates the positions (RA/DEC)
(via the keywords CRVAL/CTYPE/CRPIX/CD), the number of pixels (via the
keyword NAXIS), as well as the units (UNIT) and the resolution in
human reading format (RESOL). The number of pixels, the sizes, and the
coordinates change for one "version" to an other. But these quantities
are identical for the different extensions which have the same version
name.
The two primary keys are the extension name and the version number.
The version number indicates the resolution:
version+8=resolution in arcsec/pixel.
Objects:
-----------------------------------------
RA (2000) DE Designation(s)
-----------------------------------------
01 33 50.90 +30 39 35.8 M33 = NGC 598
-----------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
cube.fits 2880 258535 M33 images FITS data cube
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See also:
J/A+A/476/1161 : Spitzer photometry of M33 (Verley+, 2007)
J/AJ/142/111 : Total infrared brightness and SFR in M33 (Boquien+, 2011)
J/A+A/549/A17 : IRAM spectra toward M33 Giant Molecular Clouds
(Buchbender+, 2013)
J/A+A/552/A140 : SEDs of M33 HII regions (Relano+, 2013)
Acknowledgements:
Mederic Boquien, mboquien(at)ast.cam.ac.uk
(End) Patricia Vannier [CDS] 25-Feb-2015