J/ApJS/99/701 EMSS (Fleming+ 1995)
THE EINSTEIN Extended medium sensitivity survey second epoch:
results for the stars
Fleming T.A., Molendi S., Maccacaro T., Wolter A.
<Astrophys. J. Suppl. Ser. 99, 701 (1995)>
=1995ApJS...99..701F 1995ApJS...99..701F (SIMBAD/NED BibCode)
ADC_Keywords: X-ray sources
Mission_Name: Einstein
Keywords: stars: coronae - surveys - X-rays: stars
Abstract:
We present X-ray data from the ROSAT all-sky survey for those sources
catalogued in the Einstein Extended Medium Sensitivity Survey (EMSS)
(Cat. VII/152) which have been identified with Galactic stars. This
"second epoch" of X-ray data taken 10yr later, is used to study
coronal flux variability for the most active examples of late-type
stars. About 72% of the EMSS stars have been redetected by ROSAT.
While the F-stars appear to have remained constant, we find evidence
for a general decrease in X-ray flux for the M and solar-type stars.
This is probably due to the fact that an X-ray-selected sample will
preferentially detect stars while flaring. In contradiction to this,
the RS CVn binaries have been redetected at higher X-ray flux levels
for the sample as a whole.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1 72 217 R0SAT PSPC survey data on all stars from the EMSS
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See also:
IX/11 : ROSAT Source Catalog (Voges+ 1994)
VII/152 : EINSTEIN Observatory Extended Medium-Sensitivity Survey (EMSS)
Byte-by-byte Description of file: table1
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Bytes Format Units Label Explanations
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1- 13 A13 --- EMSS EMSS designation (See cat. VII/152)
15- 16 A2 --- Type Stellar type (1)
19 A1 --- l_ExpTime Limit flag on ExpTime
20- 25 F6.1 s ExpTime ? Total survey exposure time
26 A1 --- n_ExpTime [n] n: Not analysed
27 A1 --- l_RateTot Limit flag on RateTot
28- 32 F5.3 ct/s RateTot ? Total corrected PSPC count rate (2)
33 A1 --- n_RateTot [*] *: Count rate computed manually
35- 39 F5.3 ct/s e_RateTot ? 1-sigma error on RateTot
41 A1 --- l_RateHard Limit flag on RateHard
42- 46 F5.3 ct/s RateHard ? Total corrected PSPC hard (0.5-2.0 keV)
count rate
48- 52 F5.3 ct/s e_RateHard ? 1-sigma error on RateHard
54- 58 F5.2 --- HR ? Hardness ratio
60 A1 --- l_FluxTot Limit flag on FluxTot
61- 65 F5.2 10-16W/m2 FluxTot ? Total flux (0.1-2.4 keV) (10-13erg/cm2/s)
67 A1 --- l_FluxHard Limit flag on FluxHard
68- 72 F5.2 10-16W/m2 FluxHard ? Hard flux (0.5-2.0 keV) (10-13erg/cm2/s)
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Note (1): Types B, A, F, G, K, M : spectral types
BY : BY Dra binary
CV : cataclysmic variable
DA : white dwarf
EW : W UMa binary
FK : FK Com star
PM : pre-main-sequence star
RS : RS CVn binary
Note (2): For stars not detected, 3sigma upper limit
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History: Prepared via OCR at CDS.
(End) James Marcout, Patricia Bauer [CDS] 14-Feb-1997