J/A+A/297/391 T Tauri stars ROSAT survey (Neuhaeuser+, 1995)
ROSAT Survey observation of T Tauri stars in Taurus
Neuhaeuser R., Sterzik M.F., Schmitt J.H.M.M., Wichmann R., Krautter J.
<Astron. Astrophys. 297, 391 (1995)>
=1995A&A...297..391N 1995A&A...297..391N (SIMBAD/NED Reference)
ADC_Keywords: Stars, pre-main sequence ; X-ray sources
Mission_Name: ROSAT
Keywords: stars: formation - stars: late-type - stars: pre-main sequence -
X-rays: stars
Description:
We study the X-ray emission of T Tauri stars (TTS) in Taurus-Auriga as
observed with the spatially unbiased flux-limited ROSAT All-Sky Survey.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1 86 153 Sample of T Tauri stars (TTS) studied
table2 91 56 ROSAT ALL Sky Survey (RASS) data for TTS
above RASS detection limit
table3 128 60 Spectral fit results for detected TTS
table4 65 111 Upper limits for TTS below RASS limit
table5 95 16 Statistical significance for correlations
table6 113 19 Statistical significance for classical T Tauri
stars (CTTS) and weak-line T Tauri stars (WTTS)
being different
tablea1 89 188 Non-X-ray data for TTS studied
refs.dat 75 95 References quoted in table1 and tablea1
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See also:
V/73 : Emission-line stars in Orion population (Herbig+ 1988)
J/A+A/312/439 : New T Tauri stars in Taurus-Auriga (Wichmann+, 1996)
J/A+AS/132/173 : New weak-line T Tauri stars in Taurus-Auriga (Li+ 1998)
Byte-by-byte Description of file: table1
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Bytes Format Units Label Explanations
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1- 19 A19 --- Name Name
20 A1 --- n_Name [abc] Note on name (1)
24- 26 I3 --- HBC []? HBC number V/73 (Herbig & Bell 1988)
28- 33 A6 --- Type Type of the star (2)
35- 44 A10 --- r_Name References (detailed in refs.dat)
49- 50 I2 h RAh Right ascension J2000.0 (optical position)
52- 53 I2 min RAm Right ascension J2000.0 (optical position)
55- 58 F4.1 s RAs Right ascension J2000.0 (optical position)
59 A1 --- DE- Declination sign
60- 61 I2 deg DEd Declination J2000.0 (optical position)
63- 64 I2 arcmin DEm Declination J2000.0 (optical position)
66- 69 F4.1 arcsec DEs Declination J2000.0 (optical position)
72- 75 A4 --- r_pm References regarding proper motion
78- 79 I2 --- r_RV []? References regarding radial velocity
81- 83 I3 --- RASS []? Maximum likelihood for existence for
RASS detected objects
84 A1 --- u_RASS colon indicates source confusion
85- 86 A2 --- n_RASS 'ul' for RASS non-detections
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Note (1): Multiple designations not mentioned elsewhere:
(a) IRAS F04147+2822 (has stellar counterpart according to ref. 15)
=Kim 3-76 (CTTS candidate according to ref. 14, WTTS according
to ref. 10);
(b) GN Tau (proper motion candidate, ref. 6) = Kim 1-35 (CTTS
candidate, ref. 14) = IRAS F04362+2539 (CTTS, ref. 15; ref. 10
find GN Tau=IRAS04362+2539 to be a CTTS, too);
(c) JH 223 (WTTS, ref. 13) = Kim 1-50 (CTTS candidate, ref. 14).
Optical positions for Anon 1 is incorrect in ref. 1 and for
NTTS 043230+1746 incorrect in both ref. 1 & 3, but correct in
ref. 2 & ref. 27, respectively.
Note (2): the types are:
C : classical T Tauri stars
W : weak T Tauri stars
b : binaries
t : triples
q : quadruples
t(wwc): triple system with two W and one C
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Byte-by-byte Description of file: table2
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Bytes Format Units Label Explanations
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1- 20 A20 --- Name Name
23- 24 I2 h RAh Right ascension J2000.0 (X-ray position)
26- 27 I2 min RAm Right ascension J2000.0 (X-ray position)
29- 32 F4.1 s RAs Right ascension J2000.0 (X-ray position)
36 A1 --- DE- Declination sign
37- 38 I2 deg DEd Declination J2000.0 (X-ray position)
40- 41 I2 arcmin DEm Declination J2000.0 (X-ray position)
43- 46 F4.1 arcsec DEs Declination J2000.0 (X-ray position)
48- 51 F4.1 arcsec Dist Distance between X-ray and optical positions
52 A1 --- n_Dist [:] A colon indicates X-ray sources that
appear to be extended
54- 57 F4.2 --- HR1 [-1/1] Hardness ratio 1 (1)
60- 63 F4.2 --- e_HR1 rms uncertainty on HR1
65- 69 F5.2 --- HR2 [-1/1] Hardness ratio 2 (1)
72- 75 F4.2 --- e_HR2 rms uncertainty on HR2
77- 81 F5.1 ct Xcount Background subtracted X-ray counts (for
multiples and source confusion cases, we
list the combined number of counts).
84- 87 F4.1 ct e_Xcount rms uncertainty on Xcount
89- 91 I3 s Exp RASS exposition time
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Note (1): the hardness ratios are:
HR1 = (Zh1+Zh2-Zs)/(Zh1+Zh2+Zs), HR2 = (Zh2-Zh1)/(Zh2+Zh1)
where Zs, Zh1 and Zh2 denote count rates for the ROSAT PSPC energy
bands soft (0.1 to 0.4 keV), hard 1 (0.5 to 0.9 keV) and
hard 2 (0.9 to 2.0 keV), respectively.
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Byte-by-byte Description of file: table3
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Bytes Format Units Label Explanations
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1- 20 A20 --- Name Name
22- 26 F5.2 [cm-2] logN(H) Foreground hydrogen column density
27 A1 --- u_logN(H) ':' indicates cases, where fixed
absorption did not yield good fits
(see text in Sec. 3 for details)
30- 33 F4.2 --- e(logN(H))u []? Error in absorption (upper interval)
(1)
37- 40 F4.2 --- e(logN(H))l []? Error in absorption (lower interval)
(1)
43- 46 F4.2 keV k.Tx X-ray emission energy
49- 52 F4.2 keV e(k.Tx)u Error in k.Tx (upper interval)
56- 59 F4.2 keV e(k.Tx)l Error in k.Tx (lower interval)
62- 66 F5.3 10+4J/ct/cm2 1/ECF Energy conversion factor (10-11/ECF)
69- 73 F5.3 10+4J/ct/cm2 e(1/ECF)u Error in ECF (upper interval)
77- 81 F5.3 10+4J/ct/cm2 e(1/ECF)l Error in ECF (lower interval)
84- 88 F5.3 10+23W Lx Individually corrected X-ray luminosity
(Lx/10+30) (2)
92- 96 F5.3 10+23W e(Lx)u Error in Lx (upper interval)
100-104 F5.3 10+23W e(Lx)l Error in Lx (lower interval)
107-111 F5.3 10+4W/m2 Fs []? X-ray surface flux (Fs/10+7) (2)
115-119 F5.3 10+4W/m2 e(Fs)u []? Error in Fs (upper interval)
123-127 F5.3 10+4W/m2 e(Fs)l []? Error in Fs (lower interval)
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Note (1): Foreground hydrogen column density which was either held fixed
for the spectral fit, when given without errors, or, if used
as free fit parameter, fit results with errors are given
Note (2): For multiples we list X-ray luminosity and surface flux derived
by the number of components known; c.f. Sec. 3 for more details
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Byte-by-byte Description of file: table4
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Bytes Format Units Label Explanations
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1- 19 A19 --- Name Name (1)
21- 24 F4.1 arcsec Dist Offset of initial position
26- 31 F6.4 % Proba Probability of existence
33- 34 A2 --- l_Xcount [≤] limit flag on Xcount
35- 38 F4.1 ct Xcount Upper limit for the number of X-ray counts
40- 42 I3 s Exp Exposure time
44- 48 F5.3 10+4J/ct/cm2 1/ECF Energy conversion factor (10-11/ECF) (2)
49 A1 --- n_1/ECF [:] ':' average 1/ECF (2)
51- 52 A2 --- l_Lx [≤>] limit flag on Lx
53- 57 F5.3 10+23W Lx Upper limit for X-ray luminosity (Lx/10+30)
59- 60 A2 --- l_Fs [≤] limit flag on Fs
61- 65 F5.3 10+4W/m2 Fs []? Upper limit for X-ray surface flux
(Fs/10+7)
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Note (1): Components of multiple TTS are listed separately,
if individually different value for absorption or radius are used
(as for detected TTS, counts are not divided among components, but
luminosities and fluxes are divided); c.f., Sec 3.4 for more details.
Note (2): The energy conversion factor is, either calculated with
individual visual extinction and average X-ray emission temperature
for detected TTS or, if n_1/ECF = ':', the average ECF found for
detected TTS is used
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Byte-by-byte Description of file: table5
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Bytes Format Units Label Explanations
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1- 9 A9 --- Test Correlation tested
11 A1 --- n_Test [*] Note on Test (1)
13- 37 A25 --- Prop Test property
42- 49 A8 --- Unit Sample unit
52- 53 I2 --- det Number of pairs tested with detections
55- 56 I2 --- ul Upper limits detection
58- 63 F6.4 % PrCox Probability for the null hypothesis that the
correlation tested is not present according
to Cox's proportional hazard model
66- 71 F6.4 % PrKen Probability for the null hypothesis that the
correlation tested is not present according
to the Generalized Kendall's τ test
75- 80 F6.4 % PrSpe Probability for the null hypothesis that the
correlation tested is not present according
to the Spearman's ρ test
84- 89 F6.3 --- Slope []? Slope resulting from a linear regression
for correlations accepted
91- 95 F5.3 --- e_Slope []? rms uncertainty on Slope
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Note (1): When '*', tested here are correlations between degree of saturation
defined as ratio of observed over saturated X-ray luminosity and
both Wλ(Hα) and age, c.f., Sec. 4.3.
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Byte-by-byte Description of file: table6
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Bytes Format Units Label Explanations
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1- 9 A9 --- Test Test item property
10 A1 --- n_Test Note on Test (1)
14- 21 A8 --- unit Test item unit
23- 24 I2 --- CTTSs Classical T Tauri stars (CTTS) sample size
28- 29 I2 --- CTTSsul []? Upper limits of the CTTS sample size
31- 38 F8.3 --- CTTSmn CTTS mean
42- 47 F6.3 --- e_CTTSmn rms uncertainty on CTTS mean
49- 56 F8.3 --- CTTSmd []? CTTS median
58- 59 I2 --- WTTSs Weak-line T Tauri stars (WTTS) sample size
63- 64 I2 --- WTTSsul []? Upper limits of the WTTS sample size
66- 73 F8.3 --- WTTSmn WTTS mean
77- 82 F6.3 --- e_WTTSmn rms uncertainty on WTTS mean
84- 91 F8.3 --- WTTSmd WTTS median
93- 98 F6.4 % PrGWpe Probability for the null hypothesis that CTTS
and WTTS distributions are similar according
to Gehan's generalized Wilcoxon test for
permutation variance
100-105 F6.4 % PrGWhy Probability for the null hypothesis that CTTS
and WTTS distributions are similar according
to Gehan's generalized Wilcoxon test for
hypergeometric variance
108-113 F6.4 --- PrLogRank Probability for the null hypothesis that CTTS
and WTTS distributions are similar according
to the logrank test (c.f. Sec. 5.1.)
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Note (1): No median can be calculated for HR 1 for CTTS, because all data points
are in one bin. Two-sample tests for HR 1 have been performed for all TTS (a)
as well as for a co-eval sample of TTS (i.e., all TTS that are not know to be
older than the oldest detected CTTS, according to new tracks) (b).
Two-sample tests for LX have been performed for all TTS including
detections and upper limits (c), just detected TTS (d), all TTS not
originally discovered by X-rays including upper limits (e) and without upper
limits (f), as well as for all TTS that are not older than the oldest CTTS
including upper limits (g) and without upper limits (h).
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Byte-by-byte Description of file: tablea1
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Bytes Format Units Label Explanations
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1- 17 A17 --- Name Name
19- 26 A8 0.1nm EWHa Halpha equivalent width
27- 31 A5 --- r_EWHa Reference for Halpha equivalent width
33 A1 --- l_vsini limit flag on vsini
34- 36 I3 km/s vsini []? Projected surface velocity
37- 40 F4.1 d P []? Rotation period
42- 46 A5 --- r_P References for P and vsini (1)
48- 52 F5.2 solLum L []? Stellar bolometric luminosity
54- 55 I2 --- r_L []? References for the luminosity L
57- 59 F3.1 solMass Mass []? Stellar mass
60 A1 --- u_Mass uncertainty flag on M
62- 63 I2 --- r_Mass []? References for the mass M
64 A1 --- l_log(t) limit flag on age
65- 67 F3.1 [yr] log(t) []? Stellar age
68 A1 --- u_log(t) uncertainty flag on age
70- 71 I2 --- r_log(t) []? References for the age t
73- 77 F5.3 [K] log(Teff) []? Effective temperature
79- 80 I2 --- r_log(Teff) []? References for Teff
82- 86 F5.2 mag Av []? Visual extinction
88- 89 I2 --- r_Av []? References for the extinction Av
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Note (1): (*) rotation data according to ref. 48, 51, 52, & 88;
(**) rotation data according to ref. 74 to 77 & 89.
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Table 7: Detection rates
±------------------------------------------+
| Object class | sample | detected | % |
| | size | object | |
±------------------------------------------+
|(1) all TTS | 153 | 57 | 37 |
|(2) all CTTS | 79 | 9 | 11 |
|(3) all WTTS | 65 | 43 | 66 |
|(4) Single CTTS | 53 | 3 | 6 |
|(5) Single WTTS | 38 | 21 | 50 |
|(6) Binary CTTS | 20 | 2 | 10 |
|(7) Binary WTTS | 23 | 19 | 83 |
|(8) Triple TTS | 6 | 5 | 83 |
|(9) Quadruple TTS | 5 | 3 | 60 |
±------------------------------------------+
Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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2- 3 I2 --- RefNum Reference number
6- 75 A70 --- Text Text of reference, including the bibcode
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References:
See file refs.dat
(End) Patricia Bauer [CDS] 16-Nov-1994, rev. 26-Aug.1996