J/ApJ/584/911 X-rays in the Orion nebula cluster (Feigelson+, 2003)
X-rays in the Orion nebula cluster: constraints on the origins of magnetic
activity in pre-main-sequence stars.
Feigelson E.D., Gaffney III J.A., Garmire G., Hillenbrand L.A., Townsley L.
<Astrophys. J. 584, 911 (2003)>
=2003ApJ...584..911F 2003ApJ...584..911F
ADC_Keywords: Clusters, open ; Stars, pre-main sequence ; X-ray sources
Keywords: open clusters and associations: individual (Orion Nebula Cluster) -
stars: activity - stars: magnetic fields - stars: pre-main-sequence -
stars: rotation - X-rays: stars
Abstract:
A recent observation of the Orion Nebula Cluster with the ACIS
instrument on board the Chandra X-Ray Observatory detected 1075
sources, 525 of which are pre-main-sequence (PMS) stars with measured
bulk properties such as bolometric luminosities, masses, ages, and
disk indicators. Nearly half of these stars have photometrically
measured rotational periods. This provides a uniquely large and
well-defined sample to study the dependence of magnetic activity on
bulk properties for stars descending the Hayashi tracks.
Description:
The ONC was observed with the ACIS-I imaging array on board Chandra
twice during the inaugural year of the satellite, on 1999 October 12
and 2000 April 1, for 12 hr on each occasion. The satellite and
instrument are described by Weisskopf et al. (2002PASP..114....1W 2002PASP..114....1W).
The reader should consult Feigwlson et al. (2002, Cat. J/ApJ/574/258)
for an atlas of the field, full description of the data-reduction
procedures, and properties of the 1075 X-ray sources found in the
field.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 106 525 X-ray properties of well-characterized ONC stars
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See also:
J/AJ/113/1733 : Orion Nebula Cluster population (Hillenbrand 1997)
J/ApJ/437/361 : Einstein survey of the Orion nebula region (Gagne+ 1994)
J/AJ/121/3160 : JHK photometry near the Trapezium region (Carpenter+, 2001)
J/ApJ/574/258 : X-ray-emitting young stars in the Orion nebula
(Feigelson+, 2002)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 15 A15 --- CXOONC Chandra X-ray source name (1)
19- 27 A9 --- Name Associated optical star (2)
29- 33 F5.3 [K] logTeff Stellar effective temperature (1) (3)
36- 40 F5.2 [solLum] logLbol Stellar bolometric luminosity (1) (3)
44- 48 F5.2 [solMass] logM Stellar mass (1) (3)
52- 55 F4.2 [yr] logt Stellar age (1) (3)
60- 61 I2 --- DInd [-1/1]? Circumstellar disk indicator
66- 70 F5.2 d Period ? Rotational period (1)
73- 77 A5 --- r_Period Reference for Period (1) (4)
80- 84 F5.2 [---] logRo ? Log Rossby number (5)
88- 91 F4.1 [10-7W] logLs X-ray luminosity (soft band 0.5-2.5keV) (1)
95- 98 F4.1 [10-7W] logLt X-ray luminosity (total band 0.5-8keV) (1)
102-105 F4.1 [---] logLt/Lb Ratio of total-X-ray to bolometric
luminosities
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Note (1): Obtained from Feigelson et al. (2002, Cat. J/ApJ/574/258);
expressed in erg/s.
Note (2): Nomenclature note:
JW-NNN = JW NNN in Simbad
H-NNNN = [H97b] NNNN in Simbad
PSH-NN = PSH NN in Simbad
Note (3): The temperature, bolometric luminosity, mass and age values
were first derived by Hillenbrand, 1997, Cat. J/AJ/113/1733).
Note (4): Period references as follows:
C = Carpenter et al., 2001, Cat. J/AJ/121/3160
H = Herbst et al., 2000AJ....119..261H 2000AJ....119..261H, 2001ApJ...554L.197H 2001ApJ...554L.197H
S = Stassun, 1999, Cat. J/AJ/117/2941
Note (5): The Rossby number is the ratio between the measured
rotation period and the convective turnover time.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Bauer [CDS] 24-Apr-2003