J/ApJ/905/119 HOPS: Herschel/PACS 70 and 160um obs. (Fischer+, 2020)
The Herschel Orion Protostar Survey: far-infrared photometry and colors of
protostars and their variations across Orion A and B.
Fischer W.J., Megeath S.T., Furlan E., Stutz A.M., Stanke T., Tobin J.J.,
Osorio M., Manoj P., Di Francesco J., Allen L.E., Watson D.M., Wilson T.L.,
Henning T.
<Astrophys. J., 905, 119 (2020)>
=2020ApJ...905..119F 2020ApJ...905..119F
ADC_Keywords: YSOs; Photometry, infrared; Molecular clouds
Keywords: Protostars ; Star formation ; Infrared sources
Abstract:
The degree to which the properties of protostars are affected by
environment remains an open question. To investigate this, we look at
the Orion A and B molecular clouds, home to most of the protostars
within 500pc. At ∼400pc, Orion is close enough to distinguish
individual protostars across a range of environments in terms of both
the stellar and gas projected densities. As part of the Herschel Orion
Protostar Survey (HOPS), we used the Photodetector Array Camera and
Spectrometer to map 108 partially overlapping square fields with edge
lengths of 5' or 8' and measure the 70 and 160µm flux densities of
338 protostars within them. In this paper we examine how these flux
densities and their ratio depend on evolutionary state and environment
within the Orion complex. We show that Class 0 protostars occupy a
region of the 70µm flux density versus 160µm/70µm flux
density ratio diagram that is distinct from their more evolved
counterparts. We then present evidence that the Integral-Shaped
Filament (ISF) and Orion B contain protostars with more massive inner
envelopes than those in the more sparsely populated LDN 1641 region.
This can be interpreted as evidence for increasing star formation
rates in the ISF and Orion B or as a tendency for more massive inner
envelopes to be inherited from denser birth environments. We also
provide technical details about the mapmaking and photometric
procedures used in the HOPS program.
Description:
The Herschel Orion Protostar Survey (HOPS) targets were divided into
distinct spatial groups to optimize observing and were imaged in a
series of partially overlapping square maps, either 5' or 8' on a
side. We used Herschel/PACS and its scan-map astronomical observing
template, with the slowest allowed scan speed (20"/s), to
simultaneously obtain 70 and 160um images. Our first imaging data were
obtained for a single field on 2009 October 9 in the science
demonstration phase, and subsequent imaging data were obtained between
2010 March 10 and 2011 September 19. See Section 2.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 115 410 HOPS sources
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See also:
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
VI/139 : Herschel Observation Log (Herschel Science Centre, 2013)
J/A+A/289/101 : Orion OB1 association. I. (Brown+, 1994)
J/ApJ/674/336 : Spitzer observations of NGC 1333 (Gutermuth+, 2008)
J/AJ/144/31 : Spitzer+2MASS phot. of protostar candidates (Kryukova+, 2012)
J/AJ/144/192 : Spitzer survey of Orion A & B. I. YSO catalog (Megeath+, 2012)
J/AJ/145/94 : Luminosities of protostars from Spitzer (Dunham+, 2013)
J/ApJ/767/36 : APEX observations of HOPS protostars (Stutz+, 2013)
J/AJ/148/11 : Infrared photometry in Cygnus-X (Kryukova+, 2014)
J/ApJS/224/5 : Herschel Orion Protostar Survey (HOPS): SEDs (Furlan+, 2016)
J/A+A/596/A26 : OMC-2 FIR 3 and FIR 4 [OI] maps (Gonzalez-Garcia+, 2016)
J/ApJ/821/52 : NIR survey of Spitzer YSOs in Orion (Kounkel+, 2016)
J/A+A/619/A106 : 3D shape of Orion A from Gaia DR2 (Grossschedl+, 2018)
J/AJ/156/84 : APOGEE-2 survey of Orion Complex. II. (Kounkel+, 2018)
J/A+A/633/A51 : Distances to molecular clouds in SFR (Zucker+, 2020)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- HOPS [0/409] HOPS identifier
5 A1 --- n_HOPS Duplication flag on identifiers (1)
7- 13 F7.4 deg RAdeg [83.34/88.74]? Right Ascension (J2000)
15- 21 F7.4 deg DEdeg [-8.84/1.9]? Declination (J2000)
23- 33 A11 --- Region Region within Orion A and B
35- 45 A11 "Y/M/D" DateObs Observation date of group, UT
47- 56 I10 --- ObsID1 ? Herschel Observation identifier
57 A1 --- --- [-]
58- 67 I10 --- ObsID2 ? Second Herschel Observation identifier
69- 71 I3 --- Group [0/320]? Group number (2)
73- 81 E9.3 Jy F70um [0.008/1001]? Herschel/PACS 70um flux densities
83- 91 E9.3 Jy e_F70um [0.0016/50.3]? Uncertainty in F70um
93 A1 --- f_F70um Photometry type (3)
95-103 E9.3 Jy F160um [0.03/1153]? Herschel/PACS 160um flux densities
105-113 E9.3 Jy e_F160um [0.0048/58.85]? Uncertainty in F160um
115 A1 --- f_F160um Photometry type (3)
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Note (1):
2 = HOPS 109, 111, 212, and 362 are duplicates of HOPS 40, 60, 211,
and 169, respectively.
Note (2): Since sources can appear in more than one group, we list the one
for which the source position had the longest exposure time.
Note (3): Photometry types as follows:
A = aperture photometry;
P = PSF-fitted photometry;
X = not detected (but upper limits may have been determined).
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 27-Jul-2022