J/A+A/434/201 The 35um absorption line towards 1612MHz masers (He+, 2005)
A search for radiative pumping lines of OH masers.
He J.H., Szczerba R., Chen P.S., Sobolev A.M.
<Astron. Astrophys. 434, 201 (2005)>
=2005A&A...434..201H 2005A&A...434..201H
ADC_Keywords: Infrared sources ; Spectra, infrared ; Masers
Keywords: masers - stars: AGB and post-AGB - stars: circumstellar matter -
radio lines: stars
Abstract:
The 1612MHz hydroxyl maser in circumstellar envelopes has long been
thought to be pumped by 34.6µm photons. Only recently, the Infrared
Space Observatory has made possible spectroscopic observations which
enable the direct confirmation of this pumping mechanism in a few
cases. To look for the presence of this pumping line, we have searched
the Infrared Space Observatory Data Archive and found 178 spectra with
data around 34.6µm for 87 galactic 1612MHz masers.
Description:
Table 1 lists ISO SWS observations around 34.6um region for a sample
of 87 galactic OH-IR objects, and related quantities derived from the
ISO spectra and from the 1612MHz OH maser data.
Table 1a contains the supplement to Table 1 of Chen et al. (2001,
Cat. J/A+A/368/1006) and includes 49 new 1612MHz OH maser sources
with the IRAS association better than 1-arcmin. The same physical
quantities of these sources are assembled as in Chen et al. (2001,
Cat. J/A+A/368/1006).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 89 178 ISO spectral data and OH maser data of the
analysed sample of OH-IR sources
table1a.dat 134 49 Observational and derived data for the analysed
sample of OH/IR stars with IRAS LRS spectra
refs.dat 213 23 References
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See also:
VI/111 : ISO Observation Log (ISO Data Centre, 2004)
III/197 : IRAS Low Resolution Spectra (IRAS team, 1987)
II/125 : IRAS catalogue of Point Sources, Version 2.0 (IPAC 1986)
J/A+AS/127/185 : SiO masers in OH/IR stars, proto-PN and PN (Nyman+ 1998)
J/A+A/277/453 : OH maser survey of cool IRAS sources (David+ 1993)
J/A+AS/128/35 : New Sample of OH/IR stars (Sjouwerman+ 1998)
J/A+A/368/1006 : Properties of OH/IR stars with IRAS LRS spectra (Chen+, 2001)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1 A1 --- Group [ATUN] Grouping of OH-IR sources (1)
3- 12 A10 --- IRAS IRAS name
14- 18 A5 --- Type Source type given by SIMBAD (2)
20- 27 I8 --- TDT ISO spectrum name (Target Dedicated Time)
29- 34 A6 --- AOT Astronomical Observation Template (3)
36 A1 --- Sp [atun] Detection of 34.6um absorption line (4)
37- 43 F7.1 Jy Fc35um Continuum flux density around 34.6um (5)
44- 50 F7.2 Jy Sigma One sigma noise level of Fc35
51- 57 F7.1 Jy Fc35bar Representative Fc35 for each object (6)
59- 65 F7.1 Jy Fp35um ? Depth at the 34.6um absorption line center (7)
66 A1 --- n_Fp35um [#] Notes for Fp35um (8)
67- 73 F7.2 Jy FpOHb ? 1612 MHz OH maser blue peak intensity
75- 83 A9 --- r_FpOHb Reference codes for FpblueOH
85- 89 A5 --- n_FpOHb Notes for the OH 1612 MHz maser data (9)
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Note (1): Group as follows:
A = Sources with at least one a-type 34.6um ISO spectrum
T = Sources with at least one t-type but no a-type 34.6um ISO spectrum
U = Sources with only n-type and at least one u-type 34.6um spectra
N = Sources with only n-type 34.6um ISO spectra
Note (2): Type is listed as follows:
C* = Carbon Star
Cl* = Cluster of Stars
Em* = Emission-line Star
HH = Herbig-Haro Object
HII = HII (ionized) region
IG = Interacting Galaxies
IR = Infra-Red source
Maser = Maser
Mira = Variable Star of Mira Cet type
MlCl = MolCld = Molecular Cloud
OH/IR = Star with envelope of OH/IR type
OrV* = Variable Star of Orion Type
pAGB = Post-AGB Star
PN = Planetary Nebula
PN? = Possible Planetary Nebula
PV* = Pulsating variable Star
PV*s = Semi-regular pulsating Star
Star = Star
V* = Variable Star
V*? = Star suspected of Variability
WR* = Wolf-Rayet Star
YSO = Young Stellar Object
Note (3): Astronomical Observation Template:
In the case of SWS01, a number in parentheses is a scan speed mode.
Note (4): Our classification of the spectra:
a = The 34.6um absorption line is clearly detected
t = The 34.6um absorption line is tentatively detected
u = The 34.6um absorption line is expected to be seen but is not detected
n = The OH absorption is genuinely too weak and/or the spectrum is
too noisy and/or the resolution is too low.
Note (5): Negative value means bad data due to wrong dark current subtraction.
Note (6): The best value is derived by averaging among good-quality 34.6um
continuum fluxes for each OH-IR source. Negative value means bad data
due to wrong subtraction of the dark current.
Note (7): Negative flux means that the line is in absorption.
Note (8): Notes for Fp35um:
#: is used to mark three spectra. It means that: only the sub-line
No. 33 of 71101802, the sub-line No. 10 of 34201475 and the
up-scan of 28702002 are used, respectively.
Note (9): Note on FpblueOH has the following meaning:
fig = The OH peak flux intensity is measured in the figures from literature
1p = Only one OH peak is detected
* = The source IRAS 23041+1016 was listed by DC73 but no OH intensity
data was given, while it was taken as a non-detection at 1612MHz
in WB72, hence the OH maser data is missing in the table.
** = There are many OH maser counterparts for source IRAS 17424-2859.
The one nearest to the IRAS position (OH 359.946-0.048) is chosen.
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Byte-by-byte Description of file: table1a.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- Seq The sequence number in this paper
7 A1 --- LRSgroup IRAS LRS group according to Volk & Cohen
(1989AJ.....98.1918V 1989AJ.....98.1918V)
9- 19 A11 --- IRAS IRAS name
21- 33 A13 --- Name common name of the source if any
35- 36 I2 --- LRSclass ? IRAS LRS class according to the IRAS team
38- 42 F5.2 [Jy] logF12um logarithm of the IRAS PSC flux at 12 microns
44- 48 F5.2 --- C21 ? log (F25/F12)
50- 54 F5.2 --- C32 ? log (F60/F25)
56- 57 I2 % Var IRAS probability of variability
58- 64 F7.1 d Per ? Period of stellar pulsations
65- 69 F5.1 km/s Vexp ? Shell expansion velocity
71- 76 F6.1 km/s Vlsr LSR velocity of the star
77- 84 F8.2 Jy F35um ? Interpolated flux at 35 microns
85- 91 F7.2 Jy SOH ? Average OH peak flux density
93- 99 F7.2 deg GLON Galactic longitude of the IRAS source
101-106 F6.2 deg GLAT Galactic latitude of the IRAS source
108 A1 --- Assoc [0] Quality of the IRAS association
112-134 A23 --- r_SOH References to the OH maser data
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- Ref Reference code
9- 28 A20 --- BibCode BibCode
29- 55 A27 --- Aut Author's name
57-216 A160 --- Com Comments
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Acknowledgements: Jinhua He, mailhejh(at)yahoo.com.cn
(End) Jinhua He [Yunnan Observatory], Patricia Vannier [CDS] 27-Jan-2005