J/A+A/667/A124 GIARPS T Tauri spectra (GHOsT) (Gangi+, 2022)
GIARPS High-resolution Observations of T Tauri stars (GHOsT).
IV. Accretion properties of the Taurus-Auriga young association.
Gangi M., Antoniucci S., Biazzo K., Frasca A., Nisini B., Alcala J. M.,
Giannini T., Manara C.F., Giunta A., Harutyunyan A., Munari U., Vitali F.
<Astron. Astrophys. 667, A124 (2022)>
=2022A&A...667A.124G 2022A&A...667A.124G (SIMBAD/NED BibCode)
ADC_Keywords: Star Forming Region ; Stars, pre-main sequence ; Spectra, optical
Keywords: accretion, accretion disks - protoplanetary disks -
stars: low-mass - stars: pre-main sequence -
stars: variables: T Tauri, Herbig Ae/Be - techniques: spectroscopic
Abstract:
In the framework of the GIARPS High-resolution Observations of T Tauri
stars (GHOsT) project, we study the accretion properties of 37
classical T Tauri stars of the Taurus-Auriga star-forming region (SFR)
with the aim of characterizing their relation with the properties of
the central star, with jets and disk winds, and with the global disk
structure, in synergy with complementary ALMA millimeter observations.
We derive the stellar parameters, optical veiling, the accretion
luminosity (Lacc), and the mass accretion rate (dMacc/dt) in a
homogeneous and self-consistent way using high-resolution spectra
acquired at the Telescopio Nazionale Galileo with the HARPS-N and
GIANO spectrographs that are flux-calibrated based on contemporaneous
low-resolution spectroscopic and photometric ancillary observations.
The Lacc-L*, dMacc/dt-M* and dMacc/dt-Mdisk relations of the
Taurus sample are provided and compared with those of the coeval SFRs
of Lupus and Chamaeleon I. We analyzed possible causes for the
observed large spreads in the relations. We find that (i) a proper
modeling in deriving the stellar properties in highly spotted stars
can reduce the spread of the dMacc/dt-M* relation, (ii) transitional
disks tend to have lower dMacc/dt at a given M*, (iii) stars in
multiple systems have higher dMacc/dt at the same Mdisk, (iv) the
dMacc/dt versus disk surface density has a smaller spread than the
dMacc/dt-Mdisk, indicating that opacity effects might be important
in the derivation of Mdisk. Finally, the luminosities of the OI
630nm narrow low-velocity component and high-velocity component (HVC)
and the deprojected HVC peak velocity were found to correlate with the
accretion luminosity. We discuss these correlations in the framework
of the currently accepted models of jets and winds.
Our results demonstrate the potential of contemporaneous optical and
near- infrared high-resolution spectroscopy to simultaneously provide
precise measurements of the stellar wind and accretion wind properties
of young stars.
Description:
Observations were carried out from October 2017 to January 2020. They
consist of high-resolution optical and IR spectra obtained with the
GIARPS instrument that were flux-calibrated through ancillary
low-resolution spectroscopy and photometric data.
GIARPS observations.
The sample was observed in four distinct runs, hereafter run I in
October - November 2017, run II in December 2018, run III in November
2019 - January 2020, and run IV in October - December 2020. The GIARPS
observing mode consists in the simultaneous use of the HARPS-N
(resolving power R=115000) and GIANO-B (R=50000) spectrographs.
HARPSN is a fiber-fed echelle with a FoV=1" and covers the spectral
range between 390 and 690nm while GIANO-B is a nearinfrared
cross-dispersed echelle with a slit on-sky with dimensions of 6"x0.5"
and a spectral range between 940 and 2400nm.
To accurately flux-calibrate the GIARPS spectra we carried out
contemporaneous ancillary observations consisting of absolute
flux-calibrated low-resolution spectroscopy and photometry. In
particular we acquired optical low-resolution spectra (R=2400,
330-790nm) with the 1.22m telescope of the University of Padova at the
Asiago observatory (Italy). Spectra were reduced and flux-calibrated
against spectrophotometric standards flux zeropoint with BVRcIc
photometry acquired with the ANS Collaboration telescopes in runs
I-III, while in run IV, griz photometry was taken with the ROS2
instrument of the REM telescope. In the NIR we obtained JHK photometry
that was acquired in run I, II, III-2019 with the REMIR instrument at
the REM telescope and in run III-2020 and IV with the NICS camera at
the TNG telescope. In addition, we also acquired low-resolution (R∼50)
NIR spectra in run IV using the NICS Amici prism.
Fits file of the objects described in the paper are reported.
Wavelength are in angstrom and flux in erg/s/cm2/Å. Further
informations are stored in the header of each fits file.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
stars.dat 34 31 List of studied stars
list.dat 166 450 List of spectra
fits/* . 450 Individual fits spectra
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Byte-by-byte Description of file: stars.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- Star Star name
12- 13 I2 h RAh Simbad right ascension (J2000)
15- 16 I2 min RAm Simbad right ascension (J2000)
18- 22 F5.2 s RAs Simbad right ascension (J2000)
24 A1 --- DE- Simbad declination sign (J2000)
25- 26 I2 deg DEd Simbad declination (J2000)
28- 29 I2 arcmin DEm Simbad declination (J2000)
31- 34 F4.1 arcsec DEs Simbad declination (J2000)
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- Star Star name
10- 14 I5 --- Nx Number of pixels along X-axis
16- 38 A23 "datime" Obs.date Observation date
40- 48 F9.3 0.1nm blambda Lower value of wavelength interval
50- 58 F9.3 0.1nm Blambda Upper value of wavelength interval
60- 69 F10.8 0.1nm dlambda Wavelength resolution
71- 73 I3 Kibyte size Size of FITS file
75-122 A48 --- FileName Name of FITS file, in subdirectory fits
124-166 A43 --- Title Title of the FITS file
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Acknowledgements:
Manuele Gangi, manuele.gangi(at)inaf.it
References:
Giannini et al., Paper I 2019A&A...631A..44G 2019A&A...631A..44G
Gangi et al., Paper II 2020A&A...643A..32G 2020A&A...643A..32G
Alcala et al., Paper III 2021A&A...652A..72A 2021A&A...652A..72A
(End) Patricia Vannier CDS 19-Oct-2022