Effect of magnetic activity saturation in chromospheric flux–flux relationships

We present a homogeneous study of chromospheric and coronal flux–flux relationships using a sample of 298 late-type dwarf active stars with spectral types F to M. The chromospheric lines were observed simultaneously in each star to avoid spread as a result of long-term variability. Unlike other works, we subtract the basal chromospheric contribution in all the spectral lines studied. For the first time, we quantify the departure of dMe stars from the general relations. We show that dK and dKe stars also deviate from the general trend. Studying the flux–colour diagrams, we demonstrate that the stars deviating from the general relations are those with saturated X-ray emission and we show that these stars also present saturation in the Hα line. Using several age spectral indicators, we show that these are younger stars than those following the general relationships. The non-universality of flux–flux relationships found in this work should be taken into account when converting between fluxes in different chromospheric activity indicators.

[1]  David Montes Gutiérrez,et al.  Effect of magnetic activity saturation in chromospheric flux-flux relationships , 2011 .

[2]  Universidad Complutense de Madrid,et al.  A spectroscopy study of nearby late-type stars, possible members of stellar kinematic groups , 2010, 1007.1132.

[3]  M. Turatto,et al.  RACE-OC project: Rotation and variability of young stellar associations within 100 pc , 2010, 1004.1959.

[4]  Universidad Complutense de Madrid,et al.  Chromospheric activity and rotation of FGK stars in the solar vicinity - An estimation of the radial velocity jitter , 2010, 1002.4391.

[5]  M. C. Gálvez-Ortiz,et al.  A high-resolution spectroscopic survey of late-type stars: chromospheric activity, rotation, kinematics, and age , 2010, 1002.1663.

[6]  S. R. Kane,et al.  Evidence of a massive planet candidate orbiting the young active K5V star BD+20 1790 , 2009, 0912.2773.

[7]  L. Ramsey,et al.  ROTATIONAL VELOCITIES FOR M DWARFS , 2009, 0908.4092.

[8]  Gepi,et al.  An investigation of chromospheric activity spanning the Vaughan-Preston gap: impact on stellar ages , 2009, 0904.3199.

[9]  G. Micela,et al.  Quantifying the contamination by old main-sequence stars in young moving groups: the case of the Local Association , 2009, 0904.0196.

[10]  S. Hawley,et al.  χ Values for Blue Emission Lines in M Dwarfs , 2008, 0812.1221.

[11]  H. Korhonen,et al.  Magnetic activity on V889 Herculis - Combining photometry and spectroscopy , 2008 .

[12]  Germano R. Quast,et al.  Young Nearby Loose Associations , 2008, 0808.3362.

[13]  L. Hillenbrand,et al.  Improved Age Estimation for Solar-Type Dwarfs Using Activity-Rotation Diagnostics , 2008, 0807.1686.

[14]  J. Bochanski,et al.  CONSTRAINING THE AGE–ACTIVITY RELATION FOR COOL STARS: THE SLOAN DIGITAL SKY SURVEY DATA RELEASE 5 LOW-MASS STAR SPECTROSCOPIC SAMPLE , 2007, 0712.1590.

[15]  R. Díaz,et al.  Hα and the Ca II H and K lines as activity proxies for late-type stars , 2007 .

[16]  G. Micela,et al.  X-ray flares on the UV Ceti-type star CC Eridani: a ``peculiar'' time-evolution of spectral parameters , 2007, 0706.3332.

[17]  I. Busá,et al.  The CaII infrared triplet as a stellar activity diagnostic - II. Test and calibration with high resolution observations , 2007 .

[18]  E. Böhm-Vitense.  Chromospheric Activity in G and K Main-Sequence Stars, and What It Tells Us about Stellar Dynamos , 2007 .

[19]  B. Foing,et al.  Analysis and modeling of high temporal resolution spectroscopic observations of flares on AD Leonis , 2006, astro-ph/0602123.

[20]  D. Montes,et al.  The Nearest Young Moving Groups , 2006, astro-ph/0601573.

[21]  S. Hawley,et al.  Updated Colors for Cool Stars in the Sloan Digital Sky Survey , 2005 .

[22]  G. Lodato,et al.  Memorie della Società Astronomica Italiana , 2005 .

[23]  D. Montes.  HIGH TEMPORAL RESOLUTION SPECTROSCOPIC OBSERVATIONS OF UV CET TYPE FLARE STARS , 2005 .

[24]  Andrew A. West,et al.  The χ Factor: Determining the Strength of Activity in Low‐Mass Dwarfs , 2004, astro-ph/0410422.

[25]  Ben Zuckerman,et al.  Young Stars Near the Sun , 2004 .

[26]  B. Foing,et al.  High Temporal Resolution Spectroscopic Observations of the Flare Star V1054 Oph , 2004 .

[27]  T. Granzer,et al.  Doppler imaging of stellar surface structure - XXIV. The lithium-rich single K-giants DP Canum Venaticorum and DI Piscium , 2013, 1301.0445.

[28]  J. Brinkmann,et al.  Spectroscopic Properties of Cool Stars in the Sloan Digital Sky Survey: An Analysis of Magnetic Activity and a Search for Subdwarfs , 2004, astro-ph/0403486.

[29]  N. Pizzolato,et al.  Dependence of coronal X-ray emission on spot-induced brightness variations in cool main sequence stars , 2003 .

[30]  S. Hawley,et al.  Multiwavelength Observations of Flares on AD Leonis , 2003 .

[31]  Usa,et al.  An Empirical Criterion to Classify T Tauri Stars and Substellar Analogs Using Low-Resolution Optical Spectroscopy , 2003, astro-ph/0309284.

[32]  L. Ramsey,et al.  Rotational modulation of the photospheric and chromospheric activity in the young, single K2-dwarf PW And ?;?? , 2003, astro-ph/0309072.

[33]  S. Barnes.  On the Rotational Evolution of Solar- and Late-Type Stars, Its Magnetic Origins, and the Possibility of Stellar Gyrochronology , 2003, astro-ph/0303631.

[34]  UK,et al.  Simultaneous optical and X-ray observations of flares and rotational modulation on the RS CVn binary HR 1099 (V711 Tau) from the MUSICOS 1998 campaign , 2002, astro-ph/0210230.

[35]  G. Basri,et al.  Rotation and Activity in Mid-M to L Field Dwarfs , 2002, astro-ph/0201455.

[36]  N. Pizzolato,et al.  The stellar activity-rotation relationship revisited: Dependence of saturated and non-saturated X-ray emission regimes on stellar mass for late-type dwarfs ? , 2003 .

[37]  L. Eyer,et al.  New periodic variables from the Hipparcos epoch photometry , 2001, astro-ph/0112194.

[38]  D. Montes,et al.  Chromospheric activity, lithium and radial velocities of single late-type stars possible members of young moving groups , 2001, astro-ph/0110066.

[39]  D. Montes,et al.  Late-type stars members of young stellar kinematic groups - I. Single stars , 2001, astro-ph/0106537.

[40]  E. Guinan,et al.  The "rotation-activity connection": Its extension to photospheric activity diagnostics , 2001 .

[41]  D. James,et al.  X-ray emission from nearby M-dwarfs: the super-saturation phenomenon , 2000, astro-ph/0007159.

[42]  S. Saar,et al.  On Stellar Activity Enhancement Due to Interactions with Extrasolar Giant Planets , 2000, The Astrophysical journal.

[43]  R. Gershberg,et al.  Catalogue and bibliography of the UV Cet-type flare stars and related objects in the solar vicinity , 1999 .

[44]  A. Collier Cameron,et al.  Doppler Imaging of BD+22°4409 (LO Peg) Using Least Squares Deconvolution (CD-ROM Directory: contribs/lister) , 1999 .

[45]  Gianpiero Tagliaferri,et al.  CLASSIFICATION OF EUV STELLAR SOURCES DETECTED BY THE ROSAT WFC. I. PHOTOMETRIC AND RADIAL VELOCITY STUDIES , 1999 .

[46]  A. Cameron,et al.  Optical and ultraviolet observations of a strong flare in the young, single K2 dwarf LQ Hya , 1998, astro-ph/9811452.

[47]  K. Strassmeier,et al.  Starspot photometry with robotic telescopes - Continuous UBV and photometry of 23 stars in 1991–1996 , 1997 .

[48]  Robert A. Donahue,et al.  Activity-Related Radial Velocity Variation in Cool Stars , 1997 .

[49]  L. Ramsey,et al.  Multiwavelength Optical Observations of Chromospherically Active Binary Systems , 1997, astro-ph/9709185.

[50]  W. Soon,et al.  Properties of Sun-like Stars with Planets: 51 Pegasi, 47 Ursae Majoris, 70 Virginis, and HD 114762 , 1997 .

[51]  Jeffrey C. Hall.  ON THE DETERMINATION OF EMPIRICAL STELLAR FLUX SCALES , 1996 .

[52]  W. Soon,et al.  Magnetic Field and Rotation in Lower Main-Sequence Stars: An Empirical Time-Dependent Magnetic Bode's Relation? , 1996 .

[53]  M. Giampapa,et al.  The X-Ray View of the Low-Mass Stars in the Solar Neighborhood , 1995 .

[54]  R. Robinson,et al.  The chromospheres of late-type stars. II - An atlas of chromospheric lines for selected early-K stars , 1993 .

[55]  M. Giampapa,et al.  Chromospheric H-alpha and Ca II lines in late-type stars , 1990 .

[56]  G. J. Babu,et al.  Linear regression in astronomy. II , 1990 .

[57]  J. T. Hooten,et al.  Photometry of 50 suspected variable stars , 1990 .

[58]  G. Henry,et al.  Chromospheric Ca II H and K and H-alpha emission in single and binary stars of spectral types F6-M2 , 1990 .

[59]  S. Saar,et al.  Relations between the photospheric magnetic field and the emission from the outer atmospheres of cool stars. I - The solar CA II K line core emission , 1989 .

[60]  L. Hartmann,et al.  Rotation and Magnetic Activity in Main-Sequence Stars , 1987 .

[61]  Robert W. Noyes,et al.  Solar and Stellar Magnetic Activity , 1986 .

[62]  S. C. Barden,et al.  A study of short-period RS Canum Venaticorum and W Ursae Majoris binary systems - The global nature of H-alpha , 1985 .

[63]  S. Kane,et al.  Solar hard x-ray microflares , 1984 .

[64]  S. Baliunas,et al.  Rotation, convection, and magnetic activity in lower main-sequence stars , 1984 .

[65]  H. R. Johnson,et al.  Emergent Fluxes for Hydrogen-deficient Atmospheres for Cool Carbon Stars , 1984 .

[66]  D. Soderblom,et al.  An analysis of the Vaughan-Preston survey of chromospheric emission , 1984 .

[67]  Sallie L. Baliunas,et al.  Cool stars, stellar systems and the Sun , 1984 .

[68]  H. Zirin,et al.  He D3 as a diagnostic for the hard and soft X-rays from solar flares , 1983 .

[69]  D. Mihalas,et al.  A PRELIMINARY INTERPRETATION OF STELLAR CHROMOSPHERIC CA II EMISSION VARIATIONS WITHIN THE FRAMEWORK OF STELLAR DYNAMO THEORY. , 1981 .

[70]  G. Preston,et al.  A SURVEY OF CHROMOSPHERIC CA II H AND K EMISSION IN FIELD STARS OF THE SOLAR NEIGHBORHOOD. , 1980 .

[71]  B. Bopp,et al.  Binary incidence among the BY Draconis variables , 1977 .

[72]  H. Hudson,et al.  OSO-7 observations of solar x-rays in the energy range 10–100 keV , 1974 .