J/MNRAS/411/2099 Fast-rotating M-dwarf stars in NGC 2547 (Jeffries+, 2011)
Investigating coronal saturation and supersaturation in fast-rotating
M-dwarf stars.
Jeffries R.D., Jackson R.J., Briggs K.R., Evans P.A., Pye J.P.
<Mon. Not. R. Astron. Soc., 411, 2099-2112 (2011)>
=2011MNRAS.411.2099J 2011MNRAS.411.2099J
ADC_Keywords: Clusters, globular ; Stars, dwarfs ; Stars, M-type ; X-ray sources
Keywords: stars: activity - stars: coronae - stars: rotation -
open clusters and associations: individual: NGC 2547 - X-rays: stars
Abstract:
At fast rotation rates, the coronal activity of G- and K-type stars has
been observed to "saturate" and then decline again at even faster
rotation rates - a phenomenon dubbed "supersaturation". In this
paper, we investigate coronal activity in fast-rotating M-dwarfs using
deep XMM-Newton observations of 97 low-mass stars of known
rotation period in the young open cluster NGC 2547 and combine these
with published X-ray surveys of low-mass field and cluster stars of
known rotation period.
Description:
NGC 2547 was observed with XMM-Newton between UT 22:30:03 on
2007 November 12 and UT 09:30:03 on 2007 November 14 using the
European Photon Imaging Counter (EPIC) instrument, for a nominal
exposure time of 125.8ks (Observation ID 0501790101). The two
EPIC-MOS cameras and the EPIC-PN camera were operated in full-frame
mode, using the medium filter to reject optical light.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 267 69 X-ray detections of sources in the Irwin et al.
(2008, Cat. J/MNRAS/383/1588) catalogue of NGC 2547
members with rotation periods
table2.dat 130 28 The properties of stars from the Irwin et al.
(2008, Cat. J/MNRAS/383/1588) catalogue that have
known rotation periods but were not detected
within the XMM-Newton field
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See also:
J/MNRAS/335/291 : BVI photometry of NGC 2547 (Naylor+, 2002)
J/MNRAS/383/1588 : VIc photometry of NGC 2547 low-mass stars (Irwin+, 2008)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 14 A14 --- [IHA2008] Name (N2547-N-N-NNNN) (G1)
16 I1 h RAh Right ascension (J2000) (G1)
18- 19 I2 min RAm Right ascension (J2000) (G1)
21- 25 F5.2 s RAs Right ascension (J2000) (G1)
27 A1 --- DE- Declination sign (J2000) (G1)
28- 29 I2 deg DEd Declination (J2000) (G1)
31- 32 I2 arcmin DEm Declination (J2000) (G1)
34- 37 F4.1 arcsec DEs Declination (J2000) (G1)
39- 43 F5.2 mag Vmag Johnson V magnitude (G2)
45- 48 F4.2 mag V-Ic Johnson-Cousins V-I colour index (G2)
50- 55 F6.3 d Per Rotation period (G1)
57- 61 F5.2 mag BC V-band bolometric correction
63- 67 F5.2 [Lsun] logLbol Bolometric luminosity
69- 72 F4.2 [d] logtc Convective turnover time
74- 78 F5.2 [-] logNr Rossby number
80- 83 F4.2 Msun M Stellar mass
85- 88 F4.2 Rsun R Stellar radius
90- 94 F5.2 --- Rkep/R Keplerian corotation radius as a multiple of
the stellar radius
96-104 F9.5 deg RAXdeg X-ray source Right ascension
in decimal degrees (J2000)
106-113 F8.4 deg DEXdeg X-ray source Declination
in decimal degrees (J2000)
115-121 F7.1 --- ML ?=0 Maximum likelihood of the detection
123-126 F4.2 arcsec Sep ?=0 Separation from optical counterpart
128-135 E8.3 ct/s PN0 ?=-9. Total PN count rate (0.3-3keV)
137-144 E8.3 ct/s e_PN0 ?=-9. rms uncertainty on PN0
146-153 E8.3 ct/s PN1 ?=-9. PN count rate (0.3-1keV, S-band)
155-162 E8.3 ct/s e_PN1 ?=-9. rms uncertainty on PN1
164-171 E8.3 ct/s PN2 ?=-9. PN count rate (1-3keV, H-band)
173-180 E8.3 ct/s e_PN2 ?=-9. rms uncertainty on PN2
182-186 F5.2 --- HR ?=-9. HPN hardness ratio [(H-S)/(H+S)]
188-192 F5.2 --- e_HR ?=-9. rms uncertainty on HR
194-201 E8.3 ct/s M1 ?=-9. Total MOS1 count rate (0.3-3keV)
203-210 E8.3 ct/s e_M1 ?=-9. rms uncertainty on M1
212-219 E8.3 ct/s M2 ?=-9. Total MOS2 count rate (0.3-3keV)
221-228 E8.3 ct/s e_M2 ?=-9. rms uncertainty on M2
230-237 E8.3 mW/m2 Flux X-ray flux (0.3-3keV)
239-246 E8.3 mW/m2 e_Flux rms uncertainty on Flux
248-252 F5.2 --- logLx/L X-ray-to-bolometric luminosity ratio
255-258 F4.2 --- e_logLx/L rms uncertainty on logLx/Lbol
261-267 A7 --- NTJ Naylor et al., 2002, Cat. J/MNRAS/335/291
name <Cl* NGC 2547 NTJ NN-NNNN>
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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- 14 A14 --- [IHA2008] Name (N2547-N-N-NNNN) (G1)
16 I1 h RAh Right ascension (J2000) (G1)
18- 19 I2 min RAm Right ascension (J2000) (G1)
21- 25 F5.2 s RAs Right ascension (J2000) (G1)
27 A1 --- DE- Declination sign (J2000) (G1)
28- 29 I2 deg DEd Declination (J2000) (G1)
31- 32 I2 arcmin DEm Declination (J2000) (G1)
34- 37 F4.1 arcsec DEs Declination (J2000) (G1)
39- 43 F5.2 mag Vmag Johnson V magnitude (G2)
45- 48 F4.2 mag V-Ic Johnson-Cousins V-I colour index (G2)
51- 55 F5.3 d Per Rotation period (G1)
57- 61 F5.2 mag BC V-band bolometric correction
63- 67 F5.2 [Lsun] logLbol Bolometric luminosity
69- 72 F4.2 [d] logtc Convective turnover time
74- 78 F5.2 [-] logNr Rossby number
80- 83 F4.2 Msun M Stellar mass
85- 88 F4.2 Rsun R Stellar radius
90- 94 F5.2 --- Rkep/R Keplerian corotation radius
(relative to the stellar radius)
96- 98 A3 --- Inst Instrument from which X-ray count-rate upper
limit was derived (P=PN, M1=MOS1, M2=MOS2,
M12 = average from MOS1 and MOS2)
100-107 E8.3 ct/s CR Upper limit count-rate in instrument Inst
109-116 E8.3 mW/m2 Flux Upper limit X-ray flux (0.3-3keV)
118-122 F5.2 --- logLx/L Upper limit X-ray-to-bolometric luminosity
ratio
124-130 A7 --- NTJ Naylor et al., 2002, Cat. J/MNRAS/335/291
name <Cl* NGC 2547 NTJ NN-NNNN>
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Global notes:
Note (G1): From Irwin et al. (2008, Cat. J/MNRAS/383/1588).
Note (G2): modified from the Irwin et al. (2008, Cat. J/MNRAS/383/1588) values.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 14-Oct-2011