J/A+A/703/A244 Anatomy of L1489 IRS with NOEMA II (Tanious+, 2025)
Anatomy of the Class I protostar L1489 IRS with NOEMA,
II. A disk replenished by a massive streamer.
Tanious M., Le Gal R., Faure A., Maret S., Lopez-Sepulcre A., Hily-Blant P.
<Astron. Astrophys. 703, A244 (2025)>
=2025A&A...703A.244T 2025A&A...703A.244T (SIMBAD/NED BibCode)
ADC_Keywords: YSOs ; Protostars ; Molecular clouds ; Abundances ; Interferometry
Keywords: astrochemistry - radiative transfer - protoplanetary disks -
stars: low-mass - ISM: abundances - ISM: lines and bands
Abstract:
Streamers are newly identified channels that transport mass from
large, molecular-cloud scales down to small, protoplanetary-disk
scales. To better understand their impact on planet formation, it is
essential to study their physical and chemical properties.
In this framework, we aim to characterize the longest streamer
identified in carbon chain emission within the Class I system L1489
IRS, connecting the nearby prestellar core L1489 to the young stellar
object (YSO).
We observed multiple transitions of C2H, ortho-c-C3H2 and HC3N
in L1489 IRS with NOEMA and IRAM-30m at 3mm and 2mm. Using a variety
of radiative transfer methods, including a hyperfine structure (HFS)
fitting, rotational diagrams, and proposing a new self-consistent
Markov chain Monte Carlo (MCMC) approach combined with the non-LTE
RADEX code, we derived the column densities and abundances of those
molecules, as well as the H2 number density along the streamer. This
enabled us to estimate its mass, infall rate, and its impact on the
* system's mass.
We found lower limits on the streamer mass of
≥(4.67-18.3)x10-3M☉ (i.e., ≥ 0.65-2.57 times the current
disk mass) and an infall rate of ≥(1.94-7.57)x10-7M☉/yr,
where the ranges correspond to the different molecular tracers. These
values are consistent with those derived in similar Class I objects.
This suggests that the disk could be fully replenished by streamer
material. Given its mass, the streamer is likely at the origin of the
external warped disk seen in this system, as predicted by numerical
simulations. Moreover, the first investigations based on the
C2H/c-C3H2 and HC3N/c-C3H2 abundance ratios suggest that
the streamer chemistry may be inherited from the core. These results
suggest, for the first time, that the chemical composition of a Class
I object is affected by a streamer connecting a Class I YSO to its
natal environment.
We demonstrate that the streamer in L1489 IRS has a significant impact
on its disk. To better constrain how the streamer influences the
disk's chemistry and determine whether its composition is inherited
from the nearby core, further molecular surveys will be necessary
toward the prestellar core, the streamer, and the YSO. Our findings
reinforce the importance of characterizing the natal environment of
protoplanetary disks both physically (e.g., structure formation) and
chemically (e.g., material enrichment) to fully understand their
evolution.
Description:
We present the original cubes used to obtain the results from the paper.
These include NOEMA data:
- projects S20AH and W20AJ, PI: R. Le Gal;
- project S24AR, PIs: M. Tanious & R. Le Gal.
And IRAM-30m data:
- project 184-20, PI: R. Le Gal;
- project 097-24, PIs: M. Tanious & R. Le Gal.
Objects:
-------------------------------------------------------
RA (2000) DE Designation(s)
-------------------------------------------------------
04 04 43.1 +26 18 56.2 L1489 IRS = IRAS 04016+2610
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 160 16 List of fits datacubes
fits/* . 16 Individual fits datacubes
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See also:
J/A+A/475/915 : L1489IRS observed by the submillimeter array (Brinch+, 2007)
J/A+A/687/A92 : Anatomy of L1489 IRS with NOEMA I (Tanious+, 2024)
Byte-by-byte Description of file: list.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
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1- 9 F9.5 deg RAdeg Right Ascension of center (J2000)
10- 18 F9.5 deg DEdeg Declination of center (J2000)
20- 22 I3 --- Nx Number of pixels along X-axis
24- 26 I3 --- Ny Number of pixels along Y-axis
28- 30 I3 --- Nz Number of pixels along Z-axis
32- 40 F9.2 m/s bVRAD Lower value of VRAD interval
42- 49 F8.2 m/s BVRAD Upper value of VRAD interval
51- 58 F8.3 m/s dVRAD VRAD resolution
60- 81 A22 --- Line Molecular transition
83- 87 I5 Kibyte size Size of FITS file
89-124 A36 --- FileName Name of FITS file, in subdirectory fits
126-160 A35 --- Title Title of the FITS file
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Acknowledgements:
From Maxime Tanious, maxime.tanious(at)univ-grenoble-alpes.fr
Romane Le Gal, romane.le-gal(at)univ-grenoble-alpes.fr
If you use these data for a paper, please add these lines
(as requested by IRAM):
"This study is based on observations carried out under project numbers
184-20, S20AH and W20AJ (PI: Le Gal), and 097-24, S24AR (PIs: Tanious
& Le Gal), with IRAM-30m and IRAM Interferometer NOEMA. IRAM is
supported by INSU/CNRS (France), MPG (Germany) and IGN (Spain)."
References:
Tanious et al., Paper I 2024A&A...687A..92T 2024A&A...687A..92T, Cat. J/A+A/687/A92
(End) Patricia Vannier [CDS] 21-Oct-2025