Determining stellar accretion rates from $Pa_α$ and $Br_β$ emission lines with JWST NIRSpec

Ciaràn Rogers; Guido de Marchi; Bernhard Brandl

doi:10.1051/0004-6361/202449282

paper

Determining stellar accretion rates from $P a_{α}$ and $B r_{β}$ emission lines with JWST NIRSpec

arXiv:2403.09568 · doi:10.1051/0004-6361/202449282

Abstract

In this letter we present the first systematic spectroscopic measurements of the Near-InfraRed (NIR) hydrogen recombination lines Paschen alpha ( $P a_{α}$ $λ = 1.875 μ m$ ) and Brackett beta ( $B r_{β}$ $λ = 2.626 μ m$ ), produced by pre-main-sequence (PMS) stars. These stars, consisting of T Tauri and Herbig AeBe stars are located in the massive Galactic star-formation region NGC 3603. The measurements were obtained from JWST NIRSpec, using multi-object spectroscopy (MOS) mode. Utilising existing empirical relations between $L_{a cc}$ and $L_{B r_{γ}}$ , we have used our new measurements to formulate, for the first time, an empirical relationship between the accretion luminosity $L_{a cc}$ of the stars, and the line luminosities $L_{l in e}$ of both $P a_{α}$ and $B r_{β}$ . These relationships are: $lo g_{10} (\frac{L _{a cc}}{L _{⊙}}) = 1.42 (\pm 0.18) \times lo g_{10} (\frac{L _{P a_{α}}}{L _{⊙}}) + 3.33 (\pm 0.42)$ and $lo g_{10} (\frac{L _{a cc}}{L _{⊙}}) = 1.47 (\pm 0.18) \times lo g_{10} (\frac{L _{B r_{β}}}{L _{⊙}}) + 4.60 (\pm 0.57)$ . These new relationships are key for roughly estimating the accretion rates for large samples of PMS stars with JWST.

Determining stellar accretion rates from $P a_{α}$ and $B r_{β}$ emission lines with JWST NIRSpec

Abstract

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Determining stellar accretion rates from Paα​ and Brβ​ emission lines with JWST NIRSpec

Abstract

References in corpus (7)

Cited by in corpus (10)

Determining stellar accretion rates from $P a_{α}$ and $B r_{β}$ emission lines with JWST NIRSpec