![]() ![]() The X-ray hardness ratio becomes softer after brightening and then returns to a harder state as the X-rays fade. The late-time X-ray emission is well fitted by a blackbody with an effective radius of ~1 × 10 12 cm and a temperature of ~6 × 10 5 K. Initially remaining roughly constant in X-rays and slowly fading in the UV/optical, the X-ray flux increased by over an order of magnitude ~225 d after peak, resulting from the expansion of the X-ray emitting region. ![]() ASASSN-19dj peaked in the UV/optical on 2019 March 6.5 (MJD = 58548.5) at a more » bolometric luminosity of L = (6.2 ± 0.2) × 10 44 erg s -1. From the ASAS-SN g-band data, we determine that the TDE began to brighten on 2019 February 6.8 and for the first 16 d the rise was consistent with a flux ∝t 2 power law. We observed ASASSN-19dj from -21 to 392 d relative to peak ultraviolet (UV)/optical emission using high-cadence, multiwavelength spectroscopy and photometry. Here, we present observations of ASASSN-19dj, a nearby tidal disruption event (TDE) discovered in the post-starburst galaxy KUG 0810+227 by the All-Sky Automated Survey for Supernovae (ASAS-SN) at a distance of d ≃ 98 Mpc. While ASASSN-20hx has some characteristics seen in both tidal disruption events and active galactic nuclei, it cannot be definitively classified with current data. Both the optical and near-infrared spectra of ASASSN-20hx lack emission lines, unusual for any known class of nuclear transient. The X-ray emission is well fit by a power law with a photon index of Γ ∼ 2.3–2.6. Compared to an archival X-ray detection, the X-ray luminosity of ASASSN-20hx increased by an order of magnitude to L x ∼ 1.5 × 10 42 erg s −1 and then slowly declined over time. The subsequent decline is slower than any TDE observed to date and consistent with many other ANTs. ASASSN-20hx peaked in the UV/optical 30 days later on 2020 July 22.8 (MJD = 59052.8) at a bolometric luminosity of L = (3.15 ± 0.04) × more » 10 43 erg s −1. From Transiting Exoplanet Survey Satellite data, we determine that the ANT began to brighten on 2020 June 22.8 with a linear rise in flux for at least the first week. We observed ASASSN-20hx from −30 to 275 days relative to the peak UV/optical emission using high-cadence, multiwavelength spectroscopy and photometry. = ,Ībstract We present observations of ASASSN-20hx, a nearby ambiguous nuclear transient (ANT) discovered in NGC 6297 by the All-Sky Automated Survey for Supernovae (ASAS-SN). While ASASSN-20hx has some characteristics seen in both tidal disruption events and active galactic nuclei, it cannot be more » definitively classified with current data. The X-ray emission is well fit by a power law with a photon index of Γ ~ 2.3–2.6. ![]() Compared to an archival X-ray detection, the X-ray luminosity of ASASSN-20hx increased by an order of magnitude to L x ~ 1.5 × 10 42erg s -1and then slowly declined over time. ASASSN-20hx peaked in the UV/optical 30 days later on 2020 July 22.8 (MJD = 59052.8) at a bolometric luminosity ofL= (3.15 ± 0.04) × 10 43erg s -1. We observed ASASSN-20hx from -30 to 275 days relative to the peak UV/optical emission using high-cadence, multiwavelength spectroscopy and photometry. We present observations of ASASSN-20hx, a nearby ambiguous nuclear transient (ANT) discovered in NGC 6297 by the All-Sky Automated Survey for Supernovae (ASAS-SN). ![]()
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