2004A&A...424..603N


C.D.S. - SIMBAD4 rel 1.7 - 2019.10.18CEST14:47:01

2004A&A...424..603N - Astronomy and Astrophysics, volume 424, 603-612 (2004/9-3)

Accretion in brown dwarfs: An infrared view.

NATTA A., TESTI L., MUZEROLLE J., RANDICH S., COMERON F. and PERSI P.

Abstract (from CDS):

This paper presents a study of the accretion properties of 19 very low mass objects (M*∼0.01-0.1M) in the regions Chamaeleon I and ρ Oph. For 8 objects we obtained high resolution Hα profiles and determined mass accretion rate {dot}(M)ac and accretion luminosity Lac. Paβ is detected in emission in 7 of the 10 ρ Oph objects, but only in one in Cha I. Using objects for which we have both a determination of Lac from Hα and a Paβ detection, we show that the correlation between the Paβ luminosity and luminosity Lac, found by Muzerolle et al. (1998AJ....116.2965M) for T Tauri stars in Taurus, extends to objects with mass ∼0.03M; L(Paβ) can be used to measure Lac also in the substellar regime. The results were less conclusive for Brγ, which was detected only in 2 objects, neither of which had an Hα estimate of {dot}(M)ac. Using the relation between L(Paβ) and Lac we determined the accretion rate for all the objects in our sample (including those with no Hα spectrum), more than doubling the number of substellar objects with known {dot}(M)ac. When plotted as a function of the mass of the central object together with data from the literature, our results confirm the trend of lower {dot}(M)ac for lower M*, although with a large spread. Some of the spread is probably due to an age effect; our very young objects in ρ Oph have on average an accretion rate at least one order of magnitude higher than objects of similar mass in older regions. As a side product, we found that the width of Hα measured at 10% peak intensity is not only a qualitative indicator of the accreting nature of very low mass objects, but can be used to obtain a quantitative, although not very accurate, estimate of {dot}(M)ac over a large mass range, from T Tauri stars to brown dwarfs. Finally, we found that some of our objects show evidence of mass-loss in their optical spectra.

Abstract Copyright:

Journal keyword(s): stars: low-mass, brown dwarfs - stars: formation - stars: activity - line: profiles - accretion, accretion disks

CDS comments: Table 1 : objects in Cha I are [NC98] Cha HA, objects in rho Oph are ISO-Oph, except [GY92] 10.

Simbad objects: 30

goto Full paper

goto View the reference in ADS

Number of rows : 30

N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2019
#notes
1 IC 348 OpC 03 44 34 +32 09.8           ~ 1203 1
2 V* DF Tau TT* 04 27 02.7917481241 +25 42 22.456361256 11.97 12.25 11.42 10.31 9.14 M3Ve 454 1
3 EM* LkHA 331 TT* 04 31 23.814648 +24 10 52.98312   16.30 14.73 14.98   M4.5V 95 0
4 2MASS J04312405+1800215 TT* 04 31 24.0575671088 +18 00 21.455153686   20.38 18.678   14.32 M7 61 0
5 V* GN Tau TT* 04 39 20.910 +25 45 02.11 17.22     15.29   M2.5 81 0
6 V* TW Hya TT* 11 01 51.9054298616 -34 42 17.031550898   11.94 10.50 10.626 9.18 K6Ve 1443 1
7 NAME Cha I MoC 11 06 48 -77 18.0           ~ 934 1
8 [NC98] Cha HA 1 BD* 11 07 16.6694944374 -77 35 53.222755937   22.8 21.0   16.38 M8e 82 0
9 [NC98] Cha HA 9 BD* 11 07 18.5742862738 -77 32 51.553842979     23.1   17.57 M5.5e 46 0
10 CHSM 10496 Em* 11 07 37.7397076094 -77 35 30.798281267   23.7 22.2   17.03 M7.75 38 0
11 V* HK Cha Or* 11 07 42.3440888366 -77 33 59.381952754   21.9 19.8   15.26 M5.25 75 0
12 V* HL Cha Or* 11 07 52.2571569898 -77 36 57.045566163   21.5 19.51   15.07 M5.5 44 0
13 2MASS J11082404-7739299 BD* 11 08 24.0571803723 -77 39 30.044980333   22.6 21.6   17.10 M6.25 32 0
14 ISO-ChaI 144 Em* 11 08 24.1180053004 -77 41 47.441399459   21.3 19.18   14.85 M5.5 46 0
15 CHSM 12653 Em* 11 08 29.2587041357 -77 39 19.783425248   21.9 19.9   17.59 M7.25 32 0
16 V* HQ Cha Or* 11 08 39.5016839836 -77 34 16.747297668   21.7 19.75   15.06 M5.75 59 0
17 2MASS J16003023-2334457 BD* 16 00 30.2343779838 -23 34 45.617534170   20.2       M6 29 0
18 CRBR 2317.3-1925 Y*O 16 26 18.82056 -24 26 10.5216           M7 37 0
19 [GY92] 5 Y*O 16 26 21.5389368381 -24 26 01.000528521       18.30 15.80 M7 55 1
20 [GY92] 3 Y*O 16 26 21.9083577172 -24 44 39.720788042       17.95 15.62 M6.5 41 0
21 [GY92] 10 Y*O 16 26 22.18584 -24 23 52.3572           M8.5 27 0
22 [RR90] Oph 2320.8-1721 Y*O 16 26 22.26912 -24 24 07.0632           M8 61 0
23 NAME VLA 1623-243 Y*O 16 26 26.42 -24 24 30.0           ~ 366 0
24 [SSG2006] MMS002 smm 16 26 26.50 -24 24 30.9           ~ 241 0
25 [GY92] 204 Y*O 16 27 06.5924723987 -24 41 48.883697790       17.57 15.43 M5 76 0
26 BKLT J162737-241756 Y*O 16 27 37.4272403427 -24 17 54.955552302           M7.5 22 0
27 [GY92] 310 Y*O 16 27 38.6280925403 -24 38 39.230714152         17.40 M8 57 0
28 [GY92] 350 Y*O 16 27 46.2918321741 -24 31 41.264641200           M7.5 31 0
29 NAME Ophiuchus Molecular Cloud SFR 16 28 06 -24 32.5           ~ 2929 0
30 BKLT J162812-241138 Y*O 16 28 12.7237256177 -24 11 35.723756180           M6 22 0

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2004A&A...424..603N and select 'bookmark this link' or equivalent in the popup menu


2019.10.18-14:47:01

© Université de Strasbourg/CNRS

    • Contact