J/ApJ/677/401 Xray properties of protostars in ONC (Prisinzano+, 2008)
X-ray properties of protostars in the Orion nebula.
Prisinzano L., Micela G., Flaccomio E., Stauffer J.R., Megeath T.,
Rebull L., Robberto M., Smith K., Feigelson E.D., Grosso N., Wolk S.
<Astrophys. J., 677, 401-424 (2008)>
=2008ApJ...677..401P 2008ApJ...677..401P
ADC_Keywords: YSOs ; X-ray sources ; Photometry, infrared ;
Cross identifications ; Clusters, open
Keywords: open clusters and associations: general - stars: activity -
open clusters and associations: individual (Orion Nebula Cluster) -
stars: pre-main sequence - X-rays: stars
Abstract:
The origin and evolution of the X-ray emission in very young stellar
objects (YSOs) are not yet well understood because it is very hard to
observe YSOs in the protostellar phase. Using COUP data, we study the
X-ray properties of stars in the ONC in different evolutionary
classes: luminosities, hydrogen column densities NH, effective plasma
temperatures, and time variability are compared to understand if the
interaction between the circumstellar material and the central object
can influence the X-ray emission. We have assembled the deepest and
most complete photometric catalog of objects in the ONC region from
the UV to 8um using data from the HST Treasury Program; deep and
almost simultaneous UBVI and JHK images taken, respectively, with WFI
at ESO 2.2m and ISPI at CTIO 4m telescopes; and Spitzer IRAC imaging.
We select high-probability candidate Class 0-I protostars, a sample
of "bona fide" Class II stars, and a set of Class III stars with IR
emission consistent with normal photospheres. Our principal result is
that Class 0-Ia objects are significantly less luminous in X-rays, in
both the total and hard bands, than the more evolved Class II stars
with mass larger than 0.5M☉; the latter show X-ray luminosities
similar to those of Class 0-Ib stars.
Description:
A detailed description of the optical-IR observations is given in
Table 1.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 100 8 Log of the new optical-IR observations used
in this work
table2.dat 121 23 NIR photometry of Class 0/Ia candidates
table3.dat 121 22 NIR photometry of Class 0/Ib candidates
table4.dat 121 148 NIR photometry of Class II candidates
table5.dat 121 205 NIR photometry of Class III candidates
table8.dat 77 130 X-ray parameters of the Class II candidates
table9.dat 77 160 X-ray parameters of the Class III candidates
table14.dat 46 45 Literature Class 0/I counterparts
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See also:
J/ApJ/574/258 : X-ray-emitting young stars in the Orion nebula (Feigelson+,
2002)
J/ApJ/582/382 : Chandra X-ray sources in Orion Nebula Cluster (Flaccomio+,
2003)
J/ApJ/584/911 : X-rays in the Orion nebula cluster (Feigelson+, 2003)
J/AJ/130/1763 : 11.7µm point sources in Orion (Smith+, 2005)
J/AJ/129/1534 : Mid-IR photometry in the Orion Nebula (Robberto+, 2005)
J/ApJS/160/319 : COUP: observations and source lists (Getman+, 2005)
J/ApJS/160/450 : X-ray emission in Orion Nebula young stars (Flaccomio+, 2005)
J/ApJ/660/704 : Optical and X-ray variability of ONC PMS (Stassun+, 2007)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 13 A13 --- ObsDate Night(s) of observation
15- 28 A14 --- Tel Telescope used
29 A1 --- f_Tel [d] Flag for Spitzer (1)
31- 35 A5 --- Cam Camera used
37- 56 A20 --- Filter Filters
57 A1 --- f_Filter [c] Flag for WFPC2 filters (2)
59- 68 A10 s Exp Exposure time per filter
70- 80 A11 --- Lim Magnitude limit (3)
82- 98 A17 --- Field Field of view
100 I1 --- Ref Reference (4)
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Note (1): d = Data part of the Spitzer GTO Programs 43 and 50 taken in high
dynamic range mode using 0.6 and 12s at each position.
Note (2): c = WFPC2 filters F336W, F439W, F656N, and F814W correspond to the
standard filters U, B, Hα, and I, respectively.
Note (3): Magnitude limit computed for stars with photometric errors smaller
than 0.1.
Note (4): References as follows:
1 = Robberto et al. (2005AAS...20714601R 2005AAS...20714601R);
2 = M. Robberto et al. (2008ApJ...687L..83R 2008ApJ...687L..83R);
3 = Megeath et al. (2005IAUS..227..383M 2005IAUS..227..383M)
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Byte-by-byte Description of file: table[2345].dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq Sequence number (<[PMF2008] NNN> in Simbad)
5- 8 I4 --- COUP ? The COUP identification number
10- 19 F10.7 deg RAdeg Right Ascension in decimal degrees (J2000)
21- 30 F10.7 deg DEdeg Declination in decimal degrees (J2000)
32- 37 F6.3 mag Jmag ? 2MASS J band magnitude
39- 43 F5.3 mag e_Jmag ? Uncertainty in Jmag
45- 50 F6.3 mag Hmag ? 2MASS H band magnitude
52- 56 F5.3 mag e_Hmag ? Uncertainty in Hmag
58- 63 F6.3 mag Kmag ? 2MASS K band magnitude
65- 69 F5.3 mag e_Kmag ? Uncertainty in Kmag
71- 76 F6.3 mag 3.6mag Spitzer/IRAC 3.6 micron band magnitude
78- 82 F5.3 mag e_3.6mag Uncertainty in 3.6mag
84- 89 F6.3 mag 4.5mag ? Spitzer/IRAC 4.5 micron band magnitude
91- 95 F5.3 mag e_4.5mag ? Uncertainty in 4.5mag
97-102 F6.3 mag 5.8mag ? Spitzer/IRAC 5.8 micron band magnitude
104-108 F5.3 mag e_5.8mag ? Uncertainty in 5.8mag
110-115 F6.3 mag 8.0mag ? Spitzer/IRAC 8.0 micron band magnitude
117-121 F5.3 mag e_8.0mag ? Uncertainty in 8.0mag
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Byte-by-byte Description of file: table[89].dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq Sequence number (<[PMF2008] NNN> in Simbad)
5- 8 I4 --- COUP ? The COUP identification number
10- 14 F5.2 [cm-2] logNH Log of the HI column density
16- 19 F4.2 [cm-2] e_logNH Uncertainty in logNH
21- 25 F5.2 keV kT1 First model plasma temperature
27- 31 F5.2 keV e_kT1 Uncertainty in kT1
33- 37 F5.2 [cm-3] logEM1 Log of first model emission measure
39- 42 F4.2 [cm-3] e_logEM1 Uncertainty in log EM1
44- 48 F5.2 keV kT2 ? Second model plasma temperature
50- 54 F5.2 keV e_kT2 ? Uncertainty in kT2
56- 60 F5.2 [cm-3] logEM2 ? Log of second model emission measure
62- 65 F4.2 [cm-3] e_logEM2 ? Uncertainty in log EM2
67- 71 F5.2 [10-7W] logLhc Log of hard 2-8keV luminosity (1)
73- 77 F5.2 [10-7W] logLtc Log of total 0.5-8keV luminosity (1)
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Note (1): Absorption corrected and in units of erg/s.
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Byte-by-byte Description of file: table14.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Seq Sequence number (<[PMF2008] NNN> in Simbad)
4- 7 A4 --- Class YSO 0-I class (a or b)
9- 12 I4 --- COUP ? The COUP identification number
( in Simbad)
14- 21 A8 --- LMH00 Lada et al., 2000AJ....120.3162L 2000AJ....120.3162L identification
( in Simbad)
22- 25 I4 --- MLLA02 ? Muench et al., 2002, Cat. J/ApJ/573/366
identification ( in Simbad)
27- 28 I2 --- SBS04 ? Smith et al., 2004ApJ...610L.117S 2004ApJ...610L.117S
identification ( in Simbad)
30- 36 A7 --- SBS04n Smith et al., 2004ApJ...610L.117S 2004ApJ...610L.117S name
38- 39 I2 --- SBS05 ? Smith et al., 2005, Cat. J/AJ/130/1763
identification
41- 46 A6 --- RBP05 Robberto et al., 2005, Cat. J/AJ/129/1534
identification ( in Simbad)
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 15-Sep-2010