J/A+A/594/A77 KMOS star-forming galaxies Halpha data cubes (Di Teodoro+, 2016)
Flat rotation curves and low velocity dispersions in KMOS star-forming
galaxies at z ∼ 1.
Di Teodoro E.M., Fraternali F., Miller S.
<Astron. Astrophys. 594, A77 (2016)>
=2016A&A...594A..77D 2016A&A...594A..77D (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, nearby ; Velocity dispersion
Keywords: galaxies: evolution - galaxies: high-redshift -
galaxies: kinematics and dynamics
Abstract:
The study of the evolution of star-forming galaxies requires the
determination of accurate kinematics and scaling relations out to
high redshift. In this paper we select a sample of 18 galaxies at z∼1,
observed in the Hα emission-line with KMOS, to derive accurate
kinematics using a novel 3D analysis technique. We use the new code
3DBarolo that models the galaxy emission directly in the 3D
observational space, without the need to extract kinematic maps. This
technique's major advantage is that it is not affected by beam
smearing and thus it enables the determination of rotation velocity
and intrinsic velocity dispersion, even at low spatial resolution. We
find that: 1) the rotation curves of these z∼1 galaxies rise very
steeply within few kiloparsecs and remain flat out to the outermost
radius and 2) the Hα velocity dispersions are low, ranging from
15 to 40km/s, which leads to V/σ=3-10. These characteristics are
similar to those of disc galaxies in the local Universe. Finally, we
also report no significant evolution of the stellar-mass Tully-Fisher
relation. Our results show that disc galaxies are kinematically mature
and rotation-dominated already at z∼1.
Description:
KMOS datacubes of the 18 galaxies at redshift 1 used in this work. The
data are cut around the H-alpha emission-line. All information about
the data reduction can be found in the FITS file headers.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 89 18 The sample of 18 disc galaxies at z∼1 analyzed
in this work
list.dat 139 18 List of datacubes
fits/* . 18 Individual datacubes
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Seq Sequential number
4- 14 A11 --- Name Galaxy name adopted in the main survey
(KROSS or KMOS3D)
15 A1 --- n_Name [W] Note on Name (1)
17- 23 A7 --- Field Field name
25- 26 I2 h RAh Right ascension (J2000)
28- 29 I2 min RAm Right ascension (J2000)
31- 35 F5.2 s RAs Right ascension (J2000)
37 A1 --- DE- Declination sign (J2000)
38- 39 I2 deg DEd Declination (J2000)
41- 42 I2 arcmin DEm Declination (J2000)
44- 47 F4.1 arcsec DEs Declination (J2000)
49- 53 F5.3 --- z Spectroscopic redshift
55- 59 F5.2 [Msun] logM* Stellar mass (2)
61- 64 F4.2 [Msun] e_logM* rms uncertainty on logM*
66- 69 F4.1 Msun/yr SFR Star formation rate (3)
71 A1 --- n_SFR [1] Note on SFR (1)
73- 74 I2 deg i Estimated inclination angle
76- 78 I3 km/s Vflat Velocity of the flat part of the rotation
curve (4)
80- 81 I2 km/s E_Vflat Error on Vflat (upper value)
83- 84 I2 km/s e_Vflat Error on Vflat (lower value)
86- 87 I2 km/s <sigmaHa> Intrinsic Hα velocity dispersion
averaged over the entire galaxy disc as
derived in this work
89 I1 km/s e_<sigmaHa> rms uncertainty on <sigmaHa>
--------------------------------------------------------------------------------
Note (1): Notes as follows:
W = Galaxies belonging to the KMOS3D (Wisnioski et al., 2015ApJ...799..209W 2015ApJ...799..209W)
survey
Unmarked galaxies belong to the KROSS (Stott et al., 2016MNRAS.457.1888S 2016MNRAS.457.1888S)
survey
1 = SFR from Halpha integrated flux (Kennicutt, 1998ARA&A..36..189K 1998ARA&A..36..189K).
Note (2): Stellar masses from CANDELS (Santini et al., 2015, Cat J/ApJ/801/97)
or COSMOS/3D-HST (see text).
Note (3): Star formation rates from 3D-HST (Whitaker et al.,
2014ApJ...795..104W 2014ApJ...795..104W, SFRUV + SFRIR) or derived from integrated Hα
flux (lower limits).
Note (4): Velocity of the flat part of the rotation curve, defined as
specified in Section 4, derived in this work.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: list.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 F9.5 deg RAdeg Right Ascension of center (J2000)
10- 18 F9.5 deg DEdeg Declination of center (J2000)
20- 21 I2 --- Nx Number of pixels along X-axis
23- 24 I2 --- Ny Number of pixels along Y-axis
26- 27 I2 --- Nz Number of pixels along Z-axis
29- 52 A24 --- Obs.date Observation date (YYYY-MM-DDThh:mm:ss.sss)
54- 60 F7.5 um bWAVE Lower value of wavelength interval
62- 68 F7.5 um BWAVE Upper value of wavelength interval
70- 80 F11.9 um dWAVE Wavelength resolution
82- 84 I3 Kibyte size Size of FITS file
86-104 A19 --- FileName Name of FITS file, in subdirectory fits
106-139 A34 --- Title Title of the FITS file
--------------------------------------------------------------------------------
Acknowledgements:
Enrico Di Teodoro, Enrico.diTeodoro(at)anu.edu.au
(End) Enrico Di Teodoro [ANU, Australia], Patricia Vannier [CDS] 27-Jul-2016