EMISSA -- Exploring Millimeter Indicators of Solar-Stellar Activity I. The Initial mm-cm Main Sequence Star Sample

Abstract

Due to their wide wavelength coverage across the millimetre to centimetre (mm - cm) range and their increased sensitivity, modern interferometric arrays facilitate observations of the thermal and non-thermal emission from different stellar atmospheric layers. We study the spectral energy distribution ($S_{obs}(\nu )$) of main sequence stars using archival mm - cm data with the aim to study their atmospheric stratification as a function of stellar type. The main-sequence stars with significant detection in mm bands were identified in the ALMA Science Archive. These data were complemented with spectral flux data in the Ultra violet to centimetre range as compiled from various catalogues and observatory archives. We compare the resultant $S_{obs}(\nu )$ of each star with a photospheric emission model ($S_{mod}(\nu )$) calculated with the PHOENIX code. The departures of $S_{obs}(\nu )$ from the model are quantified in terms of a "spectral flux excess" parameter ($\Delta S/S_{mod}(\nu )$) for every star in the sample. The initial sample consists of 12 stars across a range of spectral type from A1 to M3.5 and the Sun-as-a-star as reference. The stars with $T_{eff}=4000-7000K$ (F - M type) showed a systematically higher $\Delta S/S_{mod}$ in the mm - cm range, with the values rising with decreasing $\nu$. The steepness of this rise is higher for cooler stars, though the fully convective 3000 K star in the sample deviated from this trend. For the A-type stars, $\Delta S/S_{mod}\sim 0$ within errors. The high $\Delta S/S_{mod}$ in cool stars points to the presence of hotter upper atmospheric layers, i.e. a chromosphere and corona, like for the Sun. The mm - cm $\Delta S/S_{mod}$ spectrum offers a way to estimate the efficiency of the heating mechanisms across various atmospheric layers and thereby to understand their structure and activity. We emphasise the need for more mm - cm data.

arXiv commentAccepted for publication in A&A

References in corpus (110)

• Gaia Data Release 2. Summary of the contents and survey properties
• Validation of the new Hipparcos reduction
• The Infrared Array Camera (IRAC) for the Spitzer Space Telescope
• A new extensive library of PHOENIX stellar atmospheres and synthetic spectra
• A Survey of Stellar Families: Multiplicity of Solar-Type Stars
• Improved Age Estimation for Solar-Type Dwarfs Using Activity-Rotation Diagnostics
• The Revised TESS Input Catalog and Candidate Target List
• The stellar activity-rotation relationship and the evolution of stellar dynamos
• On the rotational evolution of solar- and late-type stars, its magnetic origins, and the possibility of stellar gyrochronology
• Magnetic fields of non-degenerate stars
• Theory of Low-Mass Stars and Substellar Objects
• Chromospheric CaII Emission in Nearby F, G, K, and M stars
• The Geneva-Copenhagen Survey of the Solar neighbourhood III. Improved distances, ages, and kinematics
• Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 parsecs: The Northern Sample I
• The Expanded Very Large Array -- a New Telescope for New Science
• Large-scale magnetic topologies of late M dwarfs
• Stellar magnetism: empirical trends with age and rotation
• How Dry is the Brown Dwarf Desert?: Quantifying the Relative Number of Planets, Brown Dwarfs and Stellar Companions around Nearby Sun-like Stars
• The HARPS-TERRA project I. Description of the algorithms, performance and new measurements on a few remarkable stars observed by HARPS
• Structure and Evolution of Nearby Stars with Planets II. Physical Properties of ~1000 Cool Stars from the SPOCS Catalog
• Stellar Radio Astronomy. Probing Stellar Atmospheres from Protostars to Giants
• Stellar Flares from the First Tess Data Release: Exploring a New Sample of M-dwarfs
• Stellar Abundances in the Solar Neighborhood: The Hypatia Catalog
• Proxima's orbit around Alpha Centauri
• Catalogue of [Fe/H] determinations for FGK stars : 2001 edition
• The Sirius System and its Astrophysical Puzzles: Hubble Space Telescope and Ground-Based Astrometry
• Frequency of Debris Disks around Solar-Type Stars: First Results from a Spitzer/MIPS Survey
• Rotational velocities of A-type stars IV. Evolution of rotational velocities
• Oxygen Abundances in Nearby FGK Stars and the Galactic Chemical Evolution of the Local Disk and Halo
• Chromospheric activity catalogue of 4454 cool stars. Questioning the active branch of stellar activity cycles
• The Extreme Ultraviolet and X-Ray Sun in Time: High-Energy Evolutionary Tracks of a Solar-Like Star
• NEXXUS: A comprehensive ROSAT survey of coronal X-ray emission among nearby solar-like stars
• Rotational velocities of A-type stars II. Measurement of vsini in the northern hemisphere
• Lithium abundances in nearby FGK dwarf and subgiant stars: internal destruction, Galactic chemical evolution, and exoplanets
• The PASTEL catalogue: 2016 version
• A Bcool magnetic snapshot survey of solar-type stars
• On the Age and Binarity of Fomalhaut
• Chromospheric activity as age indicator
• BANYAN. III. Radial velocity, Rotation and X-ray emission of low-mass star candidates in nearby young kinematic groups
• From Radio to X-ray: Flares on the dMe Flare Star EV Lacertae
• Solar science with the Atacama Large Millimeter/submillimeter Array - A new view of our Sun
• The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets
• Abundances in the Local Region II: F, G and K Dwarfs and Subgiants
• The theoretical calculation of the Rossby number and the `non-local' convective overturn time for pre-main sequence and early post-main sequence stars
• Flare Statistics for Young Stars from a Convolutional Neural Network Analysis of $\text{TESS}$ Data
• Detection of exocometary CO within the 440 Myr-old Fomalhaut belt: a similar CO+CO${}_2$ ice abundance in exocomets and Solar System comets
• The Revolution Revolution: magnetic morphology driven spin-down
• Herschel imaging of 61 Vir: implications for the prevalence of debris in low-mass planetary systems
• Asteroseismology and calibration of alpha Cen binary system
• The Solar Neighborhood. XXXIII. Parallax Results from the CTIOPI 0.9m Program: Trigonometric Parallaxes of Nearby Low-Mass Active and Young Systems
• Ultra-Wideband Detection of 22 Coherent Radio Bursts on M Dwarfs
• A Super-Earth and two Neptunes Orbiting the Nearby Sun-like star 61 Virginis
• Herschel images of Fomalhaut. An extrasolar Kuiper Belt at the height of its dynamical activity
• On the Nature of the Dust in the Debris Disk Around HD69830
• Exo--Zodiacal Dust Levels for Nearby Main Sequence Stars
• A Complete ALMA Map of the Fomalhaut Debris Disk
• New measurements of rotation and differential rotation in A-F stars: Are there two populations of differentially rotating stars?
• The Solar Neighborhood XXX: Fomalhaut C
• ALMA observations of the $\eta$ Corvi debris disc: inward scattering of CO-rich exocomets by a chain of 3-30 M${}_{\oplus }$ planets?
• Observing the Sun with the Atacama Large Millimeter-submillimeter Array (ALMA): Fast-Scan Single-Dish Mapping
• Explorations Beyond the Snow Line: Spitzer/IRS Spectra of Debris Disks Around Solar-Type Stars
• Detection of a Millimeter Flare From Proxima Centauri
• Incidence of debris discs around FGK stars in the solar neighbourhood
• The Separation Distribution of Ultra-Wide Binaries across Galactic Populations
• Relation of X-ray activity and rotation in M dwarfs and predicted time-evolution of the X-ray luminosity
• Age Determination for 346 Nearby Stars in the Herschel DEBRIS Survey
• Constraining Stellar Coronal Mass Ejections Through Multi-Wavelength Analysis of the Active M Dwarf EQ Peg
• Asteroseismology of alpha Cen A. Evidence of rotational splitting
• A Flare-Type IV Burst Event from Proxima Centauri and Implications for Space Weather
• Discovery of an Extremely Short Duration Flare from Proxima Centauri Using Millimeter through FUV Observations
• The Correlation Between Metallicity and Debris Disk mass
• The full spectral radiative properties of Proxima Centauri
• The Age and Progenitor Mass of Sirius B
• The binarity of Milky Way F,G,K stars as a function of effective temperature and metallicity
• Mid-infrared resolution of a 3 AU-radius debris disk around Zeta Leporis
• Millimeter radiation from a 3D model of the solar atmosphere I. Diagnosing chromospheric thermal structure
• The Northern Arc of $\epsilon$ Eridani's Debris Ring as Seen by ALMA
• X-Ray, FUV, and UV Observations of alpha Centauri B: Determination of Long-term Magnetic Activity Cycle and Rotation Period
• Analysis of membership probability in nearby young moving groups with Gaia DR2
• The Epsilon Eridani System Resolved by Millimeter Interferometry
• The large-scale magnetic field of Proxima Centauri near activity maximum
• First Detection of Thermal Radio Emission from Solar-Type Stars with the Karl G. Jansky Very Large Array
• Ca II H&K stellar activity parameter: a proxy for stellar Extreme Ultraviolet Fluxes
• Deep LMT/AzTEC millimeter observations of Epsilon Eridani and its surroundings
• The beta Pictoris association: Catalog of photometric rotational periods of low-mass members and candidate members
• Young Stars with SALT
• The Solar Neighborhood XXXI: Discovery of an Unusual Red+White Dwarf Binary at ~25 Parsecs via Astrometry and UV Imaging
• Spatially resolved imaging of the two-component eta Crv debris disk with Herschel
• ALMA Observations of the Debris Disk of Solar Analogue Tau Ceti
• Precision Millimeter Astrometry of the $\alpha$ Centauri AB System
• ALMA observations of the multiplanet system 61 Vir: What lies outside super-Earth systems?
• Radio Emission from the Exoplanetary System $\epsilon$ Eridani
• $\alpha$ Centauri A in the far infrared
• Optimizing exoplanet transit searches around low-mass stars with inclination constraints
• The differential rotation of epsilon Eri from MOST data
• Detection of Alpha Centauri at radio wavelengths: chromospheric emission and search for star-planet interaction
• Metallicity calibrations for dwarf stars and giants in the Geneva photometric system
• X-ray emission processes in stars
• The stellar content of the XMM-Newton slew survey
• MAMBO image of the debris disk around epsilon Eridani : robustness of the azimuthal structure
• The Inner Debris Structure in the Fomalhaut Planetary System
• The Solar--Stellar Connection
• How dusty is alpha Centauri? Excess or non-excess over the infrared photospheres of main-sequence stars
• The 17 GHz active region number
• Measuring stellar magnetic helicity density
• MESAS: Measuring the Emission of Stellar Atmospheres at Submm/mm wavelengths
• Detection of 2$-$4 GHz Continuum Emission from $\epsilon$ Eridani
• The MESAS Project: ALMA observations of the F-type stars $\gamma$ Lep, $\gamma$ Vir A, and $\gamma$ Vir B
• The MESAS Project: Long wavelength follow-up observations of Sirius A
• Observing Flare Stars Below 100 MHz with the LWA

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• First Millimeter Flares Detected from Epsilon Eridani with ALMA
• EMISSA -- Exploring Millimetre Indicators of Solar-Stellar Activity II. Towards a robust indicator of stellar activity
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• EMISSA: Exploring millimetre indicators of solar-stellar activity III. Comparison of Ca II indices and millimetre continua in a 3D model atmosphere
• Role of non-thermal processes in the quiescent and active millimeter spectrum of a young M dwarf