J/AJ/144/99 Near-IR spectroscopy of 36 late M dwarfs (Deshpande+, 2012)
Intermediate resolution near-infrared spectroscopy of 36 late M dwarfs.
Deshpande R., Martin E.L., Montgomery M.M., Zapatero Osorio M.R.,
Rodler F., del Burgo C., Phan Bao N., Lyubchik Y., Tata R., Bouy H.,
Pavlenko Y.
<Astron. J., 144, 99 (2012)>
=2012AJ....144...99D 2012AJ....144...99D
ADC_Keywords: Stars, M-type ; Stars, dwarfs ; Equivalent widths ; Spectral types
Keywords: brown dwarfs - planetary systems - stars: fundamental parameters -
stars: low-mass - stars: rotation - techniques: radial velocities
Abstract:
We present observations of 36 late M dwarfs obtained with the
KeckII/NIRSPEC in the J band at a resolution of ∼20000. We have
measured projected rotational velocities, absolute radial velocities,
and pseudo-equivalent widths of atomic lines. Twelve of our targets
did not have previous measurements in the literature. For the other 24
targets, we confirm previously reported measurements. We find that 13
stars from our sample have vsini below our measurement threshold
(12km/s) whereas four of our targets are fast rotators (vsini>30km/s).
As fast rotation causes spectral features to be washed out, stars with
low projected rotational velocities are sought for radial velocity
surveys. At our intermediate spectral resolution, we have confirmed
the identification of neutral atomic lines reported in McLean et al.
We also calculated pseudo-equivalent widths of 12 atomic lines. Our
results confirm that the pseudo-equivalent width of KI lines is
strongly dependent on spectral types. We observe that the
pseudo-equivalent width of FeI and MnI lines remains fairly constant
with later spectral type. We suggest that these lines are particularly
suitable for deriving metallicities for late M dwarfs.
Description:
Our sample of 36 M dwarfs was observed with the near-infrared echelle
spectrograph NIRSPEC installed at the Keck II 10m telescope. NIRSPEC
is a cryogenic cross-dispersed echelle spectrograph with an ALADDIN-3
InSb 1024*1024, 27µm detector. Our observing program was granted
one and half nights for semester 2007A (2007 Apr 30 and 2007 Jun 24,
2007 Jun 25) and two nights for semester 2007B (2007 Oct 26, 2007 Oct
27 and 2007 Dec 22, 2007 Dec 23). We used the echelle mode with the
NIRSPEC-3 (J-band) filter. For this paper we made use of six echelle
orders (m=65, 64, 61-58) which cover an effective wavelength ranges of
(1.1649-1.20011µm) and (1.24081-1.32370µm). The nominal
dispersion ranged from 0.167Å at blue wavelengths to 0.191Å at
red wavelengths, and the final resolution elements ranged from 0.55 to
0.70Å. The resolving power of our spectra ranged from
(17800-22700)Å.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 69 36 Rotational velocities and S/N
table3.dat 99 36 Radial Velocities, parallaxes and distances
table4.dat 77 36 Pseudo-equivalent widths of KI lines
table5.dat 77 36 Pseudo-equivalent widths of FeI & NaI
table6.dat 87 36 Pseudo-equivalent widths of TiI, MnI, and AlI
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See also:
J/ApJ/704/975 : Rotational velocities for M dwarfs (Jenkins+, 2009)
J/ApJ/705/1416 : Volume-limited sample of M7-M9.5 dwarfs <20pc
(Reiners+, 2009)
J/AJ/135/785 : SDSS-DR5 low-mass star spectroscopic sample (West+, 2008)
J/MNRAS/383/831 : New DENIS nearby L and late-M dwarfs (Phan-Bao+, 2008)
J/A+A/331/581 : Rotation and activity in field M dwarfs (Delfosse+ 1998)
J/A+A/446/515 : Distances of nearby ultracool dwarfs (Phan-Bao+, 2006)
J/A+A/433/151 : Spectrocopic results on ROSAT late-type stars
(Zickgraf+, 2005)
J/A+A/441/653 : 32 DENIS nearby red dwarfs (Crifo+, 2005)
J/AJ/133/439 : Luminosity function of M7-L8 ultracool dwarfs (Cruz+, 2007)
J/AJ/128/426 : Subdwarfs in the SDSS (West+, 2004)
J/A+A/401/959 : 35 DENIS late-M dwarfs between 10 & 30pc (Phan-Bao+, 2003)
J/AJ/126/2421 : 2MASS-Selected sample of ultracool dwarfs (Cruz+, 2003)
J/AJ/123/2828 : Spectroscopy of northern NLTT stars (Cruz+, 2002)
J/AJ/123/3356 : Palomar/MSU nearby star spectroscopic survey. III.
(Gizis+, 2002)
J/PASP/109/849 : Probing the LHS Catalog (Gizis+ 1997)
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 A6 --- --- [2MASSJ]
7- 22 A16 --- 2MASS 2MASS identifier (HHMMSSss+DDMMSSs)
24- 32 A9 --- OName Other name
34- 37 A4 --- SpT Spectral type
41 A1 --- l_vsini Limit flag (<) on vsini
42- 45 F4.1 km/s vsini ? Rotational velocity
47- 49 F3.1 km/s e_vsini ? Mean error on vsini
51- 52 A2 --- l_vsini1 [≤ ] Limit flag (≤) on vsini1
53- 56 F4.1 km/s vsini1 ? Rotational velocity from literature
59- 61 F3.1 km/s e_vsini1 ? Mean error on vsini1
64- 66 I3 --- S/N Signal-to-noise ratio
69 A1 --- r_vsini1 [efgh] Reference of vsini1 (G1)
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Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 A6 --- --- [2MASSJ]
7- 22 A16 --- 2MASS 2MASS identifier (HHMMSSss+DDMMSSs)
24- 32 A9 --- OName Other name
34- 37 A4 --- SpT Spectral type
40- 44 F5.1 km/s RV ? Heliocentric radial velocity
46- 48 F3.1 km/s e_RV ? Mean error on RV
51- 56 F6.2 km/s RV1 ? Radial velocity from literature
58- 60 F3.1 km/s e_RV1 ? Mean error on RV1
63- 68 F6.4 arcsec plx ? Trigonometric parallax
71- 76 F6.4 arcsec e_plx ? Mean error on plx
84- 88 F5.2 pc Dist ? Spectrophotometric distance
91- 94 F4.2 pc e_Dist ? Mean error on Dist
97- 99 A3 --- Ref [1-9,a-e ] References of parallaxes
and distances (G1)
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Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 A6 --- --- [2MASSJ]
7- 22 A16 --- 2MASS 2MASS identifier (HHMMSSss+DDMMSSs)
24- 32 A9 --- OName Other name
34- 37 A4 --- SpT Spectral type
39- 42 F4.2 0.1nm pEW1 Pseudo-equivalent width of KI at 11690Å;
in Å
44- 47 F4.2 0.1nm e_pEW1 Uncertainty in pEW1
49- 52 F4.2 0.1nm pEW2 Pseudo-equivalent width of KI at 11771Å;
in Å
54- 57 F4.2 0.1nm e_pEW2 Uncertainty in pEW2; in Å
59- 62 F4.2 0.1nm pEW3 Pseudo-equivalent width of KI at 12435Å;
in Å
64- 67 F4.2 0.1nm e_pEW3 Uncertainty in pEW3; in Å
69- 72 F4.2 0.1nm pEW4 Pseudo-equivalent width of KI at 12522Å;
in Å
74- 77 F4.2 0.1nm e_pEW4 Uncertainty in pEW4; in Å
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Byte-by-byte Description of file: table5.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 A6 --- --- [2MASSJ]
7- 22 A16 --- 2MASS 2MASS identifier (HHMMSSss+DDMMSSs)
24- 32 A9 --- OName Other name
34- 37 A4 --- SpT Spectral type
39- 42 F4.2 0.1nm pEW5 ? Pseudo-equivalent width of FeI
at 11786Å; in Å
44- 47 F4.2 0.1nm e_pEW5 ? Uncertainty in pEW5
49- 52 F4.2 0.1nm pEW6 Pseudo-equivalent width of FeI at 11886Å;
in Å
54- 57 F4.2 0.1nm e_pEW6 Uncertainty in pEW6; in Å
59- 62 F4.2 0.1nm pEW7 Pseudo-equivalent width of FeI at 11976Å;
in Å
64- 67 F4.2 0.1nm e_pEW7 Uncertainty in pEW7; in Å
69- 72 F4.2 0.1nm pEW8 ? Pseudo-equivalent width of NaI
at 12682Å; in Å
74- 77 F4.2 0.1nm e_pEW8 ? Uncertainty in pEW8; in Å
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Byte-by-byte Description of file: table6.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 A6 --- --- [2MASSJ]
7- 22 A16 --- 2MASS 2MASS identifier (HHMMSSss+DDMMSSs)
24- 32 A9 --- OName Other name
34- 37 A4 --- SpT Spectral type
39- 42 F4.2 0.1nm pEW9 ? Pseudo-equivalent width of TiI
at 12832Å; in Å
44- 47 F4.2 0.1nm e_pEW9 ? Uncertainty in pEW9
49- 52 F4.2 0.1nm pEW10 ? Pseudo-equivalent width of TiI
at 12850Å; in Å
54- 57 F4.2 0.1nm e_pEW10 ? Uncertainty in pEW10; in Å
59- 62 F4.2 0.1nm pEW11 Pseudo-equivalent width of FeI at 12899Å;
in Å
64- 67 F4.2 0.1nm e_pEW11 Uncertainty in pEW11; in Å
69- 72 F4.2 0.1nm pEW12 Pseudo-equivalent width of NaI at 13123Å;
in Å
74- 77 F4.2 0.1nm e_pEW12 Uncertainty in pEW12; in Å
79- 82 F4.2 0.1nm pEW13 ? Pseudo-equivalent width of NaI
at 13150Å; in Å
84- 87 F4.2 0.1nm e_pEW13 ? Uncertainty in pEW13; in Å
--------------------------------------------------------------------------------
Global Notes:
Note (G1): References as follows:
a = Morin et al. 2010MNRAS.407.2269M 2010MNRAS.407.2269M.
b = Tinney and Reid 1998MNRAS.301.1031T 1998MNRAS.301.1031T
c = Reiners and Basri 2009, Cat. J/ApJ/705/1416
d = Martin et al. 1997A&A...327L..29M 1997A&A...327L..29M
e = Rice et al. 2010ApJS..186...63R 2010ApJS..186...63R
f = Mohanty and Basri 2003ApJ...583..451M 2003ApJ...583..451M
g = Delfpsse et al. 1998, Cat. J/A+A/331/581
h = Reiners and Basri 2010ApJ...710..924R 2010ApJ...710..924R
1 = CHARA, see http://www.chara.gsu.edu/
2 = Phan-Bao et al. 2008, Cat. J/MNRAS/383/831
3 = Zickgraf et al. 2005, Cat. J/A+A/433/151
4 = Crifo et al. 2005, Cat. J/A+A/441/653
5 = Cruz and Reid 2002, Cat. J/AJ/123/2828
6 = Phan-Bao et al. 2003, Cat. J/A+A/401/959
7 = Cruz et al. 2007, Cat. J/AJ/133/439
8 = Allen et al. 2007ApJ...655.1095A 2007ApJ...655.1095A
History:
* 22-Oct-2013: from electronic version of the journal
* 15-Nov-2013: added tables 2 and 3, replaced the 2MASSI designation
(J1733189+463359) by its actual 2MASS name (J17331893+4633593),
and changed the spectral type of GJ406 in table2 (M6.0) to be
coherent with the the other tables.
(End) Sylvain Guehenneux [CDS] 22-Oct-2013