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The proximity and duration of the tidal disruption event (TDE) ASASSN-14li led to the discovery of narrow, blue-shifted absorption lines in X-rays and UV. The gas seen in X-ray absorption is consistent with bound material close to the apocenter of elliptical orbital paths, or with a disk wind similar to those seen in Seyfert-1 active galactic nuclei. We present a new analysis of the deepest high-resolution XMM-Newton and Chandra spectra of ASASSN-14li. Driven by the relative strengths of He-like and H-like charge states, the data require [N/C] > 2.4, in qualitative agreement with UV spectral results. Flows of the kind seen in the X-ray spectrum of ASASSN-14li were not clearly predicted in simulations of TDEs; this left open the possibility that the observed absorption might be tied to gas released in prior AGN activity. However, the abundance pattern revealed in this analysis points to a single star rather than a standard AGN accretion flow comprised of myriad gas contributions. The simplest explanation of the data is likely that a moderately massive star (M ~ 3 Msun) with significant CNO processing was disrupted. An alternative explanation is that a lower mass star was disrupted that had previously been stripped of its envelope. We discuss the strengths and limitations of our analysis and these interpretations., Comment: Accepted for publication in ApJ Letters

We present the long term analysis of GS 1826-238, a neutron star X-ray binary known as the "Clocked Burster", using data from NuSTAR StrayCats. StrayCats, a catalogue of NuSTAR stray light data, contains data from bright, off-axis X-ray sources that have not been focused by the NuSTAR optics. We obtained stray light observations of the source from 2014-2021, reduced and analyzed the data using nustar-gen-utils Python tools, demonstrating the transition of source from the "island" atoll state to a "banana" branch. We also present the lightcurve analysis of Type I X-Ray bursts from the Clocked Burster and show that the bursts from the banana/soft state are systematically shorter in durations than those from the island/hard state and have a higher burst fluence. From our analysis, we note an increase in mass accretion rate of the source, and a decrease in burst frequency with the transition.

NGC 5033 is an intriguing Seyfert galaxy because its sub-classification may change with time, and because optical and sub-mm observations find that the massive black hole does not sit at the dynamical center of the galaxy, pointing to a past merger. We obtained a new optical spectrum of NGC 5033 using the 200'' Hale telescope at Palomar that clearly reveals a broad H$\beta$ line (FWHM$=5400\pm 300~{\rm km}~{\rm s}^{-1}$). This signals a clear view of the optical broad line region (BLR) and requires Seyfert-1.5 designation. Some spectra obtained in the past suggest a Seyfert-1.9 classification, potentially signaling a variable or "changing-look" geometry. Our analysis of a 2019 Chandra spectrum of the massive black hole reveals very little obscuration, also suggesting a clean view of the central engine. However, the narrow Fe~K$\alpha$ emission line is measured to have an equivalent with of EW$=460^{+100}_{-90}$~eV. This value is extremely high compared to typical values in unobscured AGN. Indeed, the line is persistently strong in NGC 5033: the line equivalent width in a 2002 XMM-Newton snapshot is EW$=250^{+40}_{-40}$~eV, similar to the EW$=290^{+100}_{-100}$~eV equivalent width measured using ASCA in 1999. These results can likely be explained through a combination of an unusually high covering factor for reflection, and fluxes that are seen out of phase owing to light travel times. We examine the possibility that NGC 5033 may strengthen evidence for the X-ray Baldwin effect.