J/ApJ/744/20 S4MC project: 6 star forming regions PAHs (Sandstrom+, 2012)
The Spitzer Spectroscopic Survey of the Small Magellanic Cloud (S4MC):
probing the physical state of polycyclic aromatic hydrocarbons in a
low-metallicity environment.
Sandstrom K.M., Bolatto A.D., Bot C., Draine B.T., Ingalls J.G.,
Israel F.P., Jackson J.M., Leroy A.K., Li A., Rubio M., Simon J.D.,
Smith J.D.T., Stanimirovic S.Z., Tielens A.G.G.M., van Loon J.T.
<Astrophys. J., 744, 20 (2012)>
=2012ApJ...744...20S 2012ApJ...744...20S
ADC_Keywords: Magellanic Clouds ; Interstellar medium ; Spectra, infrared ;
H II regions
Keywords: dust, extinction - infrared: ISM - Magellanic Clouds
Abstract:
We present results of mid-infrared spectroscopic mapping observations
of six star-forming regions in the Small Magellanic Cloud (SMC) from
the Spitzer Spectroscopic Survey of the SMC (S4MC). We detect the
mid-IR emission from polycyclic aromatic hydrocarbons (PAHs) in all of
the mapped regions, greatly increasing the range of environments where
PAHs have been spectroscopically detected in the SMC. We investigate
the variations of the mid-IR bands in each region and compare our
results to studies of the PAH bands in the SINGS sample and in a
sample of low-metallicity starburst galaxies. PAH emission in the SMC
is characterized by low ratios of the 6-9um features relative to the
11.3um feature and weak 8.6 and 17.0um features. Interpreting these
band ratios in the light of laboratory and theoretical studies, we
find that PAHs in the SMC tend to be smaller and less ionized than
those in higher metallicity galaxies.
Description:
We mapped six star-forming regions in the SMC using the low-resolution
orders of the IRS on Spitzer as part of the S4MC project (GO 30491).
We list the details of the observations (2006/Dec/09 to 2007/Jun/11)
in Table 1.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 57 17 S4MC (Spitzer Spectroscopic Survey of the SMC)
observations
table2.dat 567 511 Spectral fit results
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See also:
J/A+A/515/A56 : NGC 346/N66 JHKs photometry (Gouliermis+, 2010)
J/ApJS/190/233 : Spectroscopy & abundances of SINGS galaxies (Moustakas+, 2010)
J/ApJ/723/895 : IR luminosities and aromatic features of 5MUSES (Wu+, 2010)
J/ApJ/705/885 : PAH in galaxies at z∼0.1 (O'Dowd+, 2009)
J/ApJ/656/770 : Mid-IR spectrum of star-forming galaxies (Smith+, 2007)
J/ApJ/669/327 : S3MC: YSOs in N66, in SMC (Simon+, 2007)
J/ApJ/655/212 : S3MC IRAC and MIPS photometry (Bolatto+, 2007)
J/A+A/469/575 : Spitzer mid-IR spectra of 3 molecular clouds (Berne+, 2007)
J/A+A/401/873 : The SMC in the Far Infrared (Wilke+, 2003)
J/ApJ/566/880 : ISO-SWS observations of H II regions (Giveon+, 2002)
J/AJ/123/855 : Magellanic Clouds Phot. Survey: the SMC (Zaritsky+, 2002)
http://irsa.ipac.caltech.edu/data/SPITZER/docs/ : Spitzer home page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- Obs Observation type: LL=long low, SL=short low
4- 14 A11 --- Name Region name
15 I1 h RAh Hour of right ascension (J2000)
17- 18 I2 min RAm Minute of right ascension (J2000)
20- 21 I2 s RAs Second of right ascension (J2000)
23 A1 --- DE- Sign of declination (J2000)
24- 25 I2 deg DEd Degree of declination (J2000)
27- 28 I2 arcmin DEm Arcminute of declination (J2000)
30- 31 I2 arcsec DEs Arcsecond of declination (J2000)
33- 43 A11 "YYYY/MMM/DD" Date Observation date
45- 52 I8 --- AOR Spitzer Astronomical Observation number
54- 57 A4 --- Reg Region abbreviation as in table 2
(column added by CDS)
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- Reg Region Name (nNN, smcb or swN)
11- 15 I5 --- Num [1/114] Extraction region number
16- 27 E12.6 deg RAdeg Right Ascension in decimal degrees (J2000)
28- 39 E12.6 deg DEdeg Declination in decimal degrees (J2000)
40- 51 E12.4 10-8W/m2/sr F6.2 The 6.2um dust feature intensity
52- 63 E12.4 10-8W/m2/sr e_F6.2 Uncertainty in F6.2
64- 75 E12.4 10-8W/m2/sr cF6.2 Corrected F6.2
76- 87 E12.4 10-8W/m2/sr e_cF6.2 Uncertainty in cF6.2
88- 99 E12.4 10-8W/m2/sr F7.7 The 7.7um Complex dust feature intensity
100-111 E12.4 10-8W/m2/sr e_F7.7 Uncertainty in F7.7
112-123 E12.4 10-8W/m2/sr cF7.7 Corrected F7.7
124-135 E12.4 10-8W/m2/sr e_cF7.7 Uncertainty in cF7.7
136-147 E12.4 10-8W/m2/sr F8.3 The 8.3um dust feature intensity
148-159 E12.4 10-8W/m2/sr e_F8.3 Uncertainty in F8.3
160-171 E12.4 10-8W/m2/sr cF8.3 Corrected F8.3
172-183 E12.4 10-8W/m2/sr e_cF8.3 Uncertainty in cF8.3
184-195 E12.4 10-8W/m2/sr F8.6 The 8.6um dust feature intensity
196-207 E12.4 10-8W/m2/sr e_F8.6 Uncertainty in F8.6
208-219 E12.4 10-8W/m2/sr cF8.6 Corrected F8.6
220-231 E12.4 10-8W/m2/sr e_cF8.6 Uncertainty in CF8.6
232-243 E12.4 10-8W/m2/sr F11.3 The 11.3um dust feature intensity
244-255 E12.4 10-8W/m2/sr e_F11.3 Uncertainty in F11.3
256-267 E12.4 10-8W/m2/sr cF11.3 Corrected F11.3
268-279 E12.4 10-8W/m2/sr e_cF11.3 Uncertainty in cF11.3
280-291 E12.4 10-8W/m2/sr F12.0 The 12.0um dust feature intensity
292-303 E12.4 10-8W/m2/sr e_F12.0 Uncertainty in F12.0
304-315 E12.4 10-8W/m2/sr cF12.0 Corrected F12.0
316-327 E12.4 10-8W/m2/sr e_cF12.0 Uncertainty in cF12.0
328-339 E12.4 10-8W/m2/sr F12.6 The 12.6um dust feature intensity
340-351 E12.4 10-8W/m2/sr e_F12.6 Uncertainty in F12.6
352-363 E12.4 10-8W/m2/sr cF12.6 Corrected F12.6
364-375 E12.4 10-8W/m2/sr e_cF12.6 Uncertainty in cF12.6
376-387 E12.4 10-8W/m2/sr F13.6 The 13.6um dust feature intensity
388-399 E12.4 10-8W/m2/sr e_F13.6 Uncertainty in F13.6
400-411 E12.4 10-8W/m2/sr cF13.6 Corrected F13.6
412-423 E12.4 10-8W/m2/sr e_cF13.6 Uncertainty in cF13.6
424-435 E12.4 10-8W/m2/sr F17.0 The 17.0um Complex dust feature intensity
436-447 E12.4 10-8W/m2/sr e_F17.0 Uncertainty in F17.0
448-459 E12.4 10-8W/m2/sr cF17.0 Corrected F17.0
460-471 E12.4 10-8W/m2/sr e_cF17.0 Uncertainty in cF17.0
472-483 E12.4 10-8W/m2/sr NeII The [Ne II] line intensity (12.8um)
484-495 E12.4 10-8W/m2/sr e_NeII Uncertainty in NeII
496-507 E12.4 10-8W/m2/sr cNeII Corrected NeII
508-519 E12.4 10-8W/m2/sr e_cNeII Uncertainty in cNeII
520-531 E12.4 10-8W/m2/sr NeIII The [Ne III] line intensity (15.6um)
532-543 E12.4 10-8W/m2/sr e_NeIII Uncertainty in NeIII
544-555 E12.4 10-8W/m2/sr cNeIII Corrected NeIII
556-567 E12.4 10-8W/m2/sr e_cNeIII Uncertainty in cNeIII
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 27-May-2013