J/A+A/695/A74 A new FUV flux catalogue for disc-hosting stars (Anania+, 2025)
A novel method for evaluating the far-ultraviolet flux and a catalogue for
disc-hosting stars in nearby regions.
Anania R., Winter A.J., Rosotti G., Vioque M., Zari E.,
Pantaleoni Gonzalez M., Testi L.
<Astron. Astrophys. 695, A74 (2025)>
=2025A&A...695A..74A 2025A&A...695A..74A (SIMBAD/NED BibCode)
ADC_Keywords: Stars, nearby ; Stars, pre-main sequence ; Ultraviolet
Keywords: accretion, accretion discs - catalogs - protoplanetary disks -
stars: distances - stars: protostars
Abstract:
When protoplanetary discs are externally irradiated by far-ultraviolet
(FUV) photons from OBA-type stars, they lose material through
photoevaporative winds. This reduces the amount of material that is
available to form planets. Understanding the link between the
environmental irradiation and the observed disc properties requires
accurately evaluating the FUV flux at disc-hosting stars, which can be
challenging because of the uncertainty in stellar parallax. We
addressed this issue by proposing a novel approach: using the local
density distribution of a star-forming region (i.e. 2D pairwise star
separation distribution) and assuming isotropy, we inferred the 3D
separation between disc-hosting stars and massive stars. We tested
this approach on synthetic clusters and showed that it significantly
improves accuracy compared to previous methods. We computed the FUV
fluxes for numerous star-bearing discs in seven regions within ∼200pc,
six regions in Orion and in Serpens sub-regions. We provided a
publicly accessible catalogue. We found that discs in regions hosting
late-type B and early-type A stars can reach non-negligible FUV
radiation levels for the disc evolution (10-100G0). We investigated
dust disc masses relative to FUV fluxes and detected indications of a
negative correlation when we restricted the investigation to average
region ages. However, we emphasize the need for more stellar and disc
observations at >10^2G0 to probe the dependence of disc properties on
environmental irradiation. The method presented in this work is a
powerful tool that can be expanded to additional regions.
Description:
We provided a catalogue of the FUV flux at the position of numerous
disc-hosting stars in nearby star-forming regions. Using our new
method, we estimated the most likely FUV flux with uncertainties.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tableb1.dat 161 1920 FUV flux at the position of the considered discs
in 14 nearby star-forming regions
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Byte-by-byte Description of file: tableb1.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- Table [0/1919] Source number
6- 15 A10 --- Region Region of the source
17- 44 A28 --- Name Name of the source (JHHMMSSss+DDMMSSs)
46- 64 F19.15 deg RAdeg Right ascension (J2000)
66- 85 F20.16 deg DEdeg Declination (J2000)
87-112 F26.16 --- FFUV 50% of the far-ultraviolet flux distribution
(in Habing unit, G0) (1)
114-136 F23.16 --- b_FFUV ?=0 16% of the far-ultraviolet flux distribution
(in Habing unit, G0) (1)
138-161 F24.16 --- B_FFUV ?=0 84% of the far-ultraviolet flux distribution
(in Habing unit, G0) (1)
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Note (1): The FUV flux is given in terms of the Habing unit, G0
(Habing, 1968BAN....19..421H 1968BAN....19..421H), which quantifies the flux integral over the
range of wavelengths [912-2400]Å, normalised to the average flux in the
solar neighbourhood (1.6x10-3erg/s/cm2)
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Acknowledgements:
Rossella Anania, rossella.anania(at)unimi.it
(End) Rossella Anania [UniMi, Italy], Patricia Vannier [CDS] 04-Feb-2025