2019/01/30 by Lynne A. Hillenbrand, Adam A. Miller, John M. Carpenter +9 · 23 citations
Physics and Astronomy · #Astronomy #Astrophysics #Astrophysics and Star Formation Studies #Gamma-ray bursts and supernovae #Infrared #Light curve #Physics #Stellar, planetary, and galactic studies #astro-ph.SR
paper · pdf · doi:10.3847/1538-4357/ab06c8
published in The Astrophysical Journal 874(1), 82 (IOP Publishing) · Accepted to ApJ
arxiv created 2019/01/30 · openalex created_date 2019/02/21 · openalex publication_date 2019/03/20 · arxiv updated 2019/04/03 · openalex updated_date 2026/08/05
Abstract We report the outbursting source PTF 14jg, which, prior to the onset of its late 2013 eruption, was a faint, unstudied, and virtually uncataloged star. The salient features of the PTF 14jg outburst are (i) projected location near the W4 H ii region and radial velocity consistent with physical association; (ii) a light curve that underwent an ∼6–7 mag optical ( R -band) through mid-infrared ( L -band) brightening on a timescale of a few months, peaked and then faded by ∼3 mag, but plateaued still >3.5 mag above quiescence by ∼8 months post-peak, lasting to at least 4 yr after eruption; (iii) strong outflow signatures with velocities reaching −530 ; (iv) a low-gravity and broad (∼100–150 FWHM) optical absorption-line spectrum that systematically changes its spectral type with wavelength; (v) lithium; and (vi) ultraviolet and infrared excess. We tentatively identify the outburst as exhibiting characteristics of a young star FU Ori event. However, the burst would be unusually hot, with an absorption spectrum exhibiting high-excitation (∼11,000–15,000 K) lines in the optical and no evidence of CO in the near-infrared, in addition to exhibiting an unusual light curve. We thus also consider alternative scenarios—including various forms of novae, nuclear-burning instabilities, massive star events, and mergers—finding them all inferior to the atypically hot FU Ori star classification. The source eventually may be interpreted as a new category of young star outburst with a larger amplitude and shorter rise time than most FU Ori–like events.