J/A+A/461/977 Rosat North Ecliptic survey stellar population (Micela+, 2007)
The stellar population of the Rosat North Ecliptic survey.
Micela G., Affer L., Favata F., Henry J.P., Gioia I., Mullis C.R.,
Sanz-Forcada J., Sciortino D.
<Astron. Astrophys. 461, 977 (2007)>
=2007A&A...461..977M 2007A&A...461..977M
ADC_Keywords: Surveys ; Radio sources ; Photometry, infrared ;
MK spectral classification
Keywords: stars: activity - stars: coronae - X-rays: stars - solar neighbourhood
Abstract:
X-ray surveys are a very efficient mean of detecting young stars and
therefore allow us to study the young stellar population in the solar
neighborhood and the local star formation history in the last billion
of years.
We want to study the young stellar population in the solar
neighborhood, to constrain its spatial density and scale height as
well as the recent local star formation history.
We analyze the stellar content of the ROSAT North Ecliptic Pole
survey, and compare the observations with the predictions derived from
stellar galactic model. Since the ROSAT NEP survey is sensitive at
intermediate fluxes is able to sample both the youngest stars and the
intermediate age stars (younger than 109years), linking the shallow
and deep flux surveys already published in the literature.
We confirm the existence of an excess of yellow stars in our
neighborhood previously seen in shallow survey, which is likely due to
a young star population not accounted for in the model. However the
excellent agreement between observations and predictions of dM stars
casts some doubt on the real nature of this active population.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 22 25 Standard stars
table2.dat 75 152 Spectral types of program stars
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See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
J/ApJS/149/29 : ROSAT North Ecliptic Pole Survey (Gioia+, 2003)
J/A+A/446/97 : NEP Distant Cluster Radio Galaxies (Branchesi+, 2006)
J/ApJS/162/304 : ROSAT NEP X-ray source catalog (Henry+, 2006)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 10 A10 -- Name Star name
12- 18 A7 -- SpType MK spectral type
20- 22 A3 -- r_SpType Spectral type reference (1)
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Note (1): Reference for SpType as follows:
(1) = Jacoby et al. (1984, Cat. III/92)
(2) = SIMBAD database. operated at CDS, Strasbourg, France
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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- 2 A2 --- --- [RX]
3- 14 A12 --- RX Source name (JHHMM.m+DDMM) from
Gioia et al., 2003, Cat. J/ApJS/149/29
16- 19 A4 --- NEP North Ecliptic Pole scan number from
Gioia et al., 2003, Cat. J/ApJS/149/29
21- 22 I2 h RAh Right ascension (J2000)
24- 25 I2 min RAm Right ascension (J2000)
27- 30 F4.1 s RAs Right ascension (J2000)
32 A1 --- DE- Declination sign (J2000)
33- 34 I2 deg DEd Declination (J2000)
36- 37 I2 arcmin DEm Declination (J2000)
39- 40 I2 arcsec DEs Declination (J2000)
42- 47 F6.3 mag Jmag ? J magnitude from 2MASS (Cat. II/246)
49- 54 F6.3 mag Hmag ? H magnitude from 2MASS (Cat. II/246)
56- 61 F6.3 mag Kmag ? K magnitude from 2MASS (Cat. II/246)
63- 70 A8 -- SpType MK spectral type
73- 75 A3 -- Note Notes (1)
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Note (1): Note as follows:
D = Discarded from the sample of the 'normal' stars
S = Spectral type from SIMBAD
G = Spectra from Gioia et al., 2003, Cat. J/ApJS/149/29
N = Spectra obtained in this work with the NOT telescope
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Acknowledgements:
Giusi Micela, giusi(at)astropa.unipa.it
(End) Patricia Vannier [CDS] 27-Nov-2006