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            The role of Artificial Intelligence (AI) in research and education continues to rapidly grow, resulting in increased collaboration between researchers in AI and Research Computing and Data (RCD) professionals to meet the research and teaching demands. RCD professionals bridge the gap between research and technology by guiding and collaborating with researchers and educators through the process of selecting the hardware, software, and services best suited for executing their AI projects. This includes ensuring compliance with funding and regulatory requirements across the entire lifecycle of the project. In this paper, we present an overview of the AI project lifecycle and how RCD professionals can facilitate its execution.more » « lessFree, publicly-accessible full text available July 18, 2026
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            Abstract We present the results from our 7 yr long broadband X-ray observing campaign of SN 2014C with Chandra and NuSTAR. These coordinated observations represent the first look at the evolution of a young extragalactic SN in the 0.3–80 keV energy range in the years after core collapse. We find that the spectroscopic metamorphosis of SN 2014C from an ordinary type Ib SN into an interacting SN with copious hydrogen emission is accompanied by luminous X-rays reaching L x ≈ 5.6 × 10 40 erg s −1 (0.3–100 keV) at ∼1000 days post-explosion and declining as L x ∝ t −1 afterwards. The broadband X-ray spectrum is of thermal origin and shows clear evidence for cooling after peak, with T ( t ) ≈ 20 keV ( t / t pk ) − 0.5 . Soft X-rays of sub-keV energy suffer from large photoelectric absorption originating from the local SN environment with NH int ( t ) ≈ 3 × 10 22 ( t / 400 days ) − 1.4 cm − 2 . We interpret these findings as the result of the interaction of the SN shock with a dense ( n ≈ 10 5 − 10 6 cm −3 ), H-rich disk-like circumstellar medium (CSM) with inner radius ∼2 × 10 16 cm and extending to ∼10 17 cm. Based on the declining NH int ( t ) and X-ray luminosity evolution, we infer a CSM mass of ∼(1.2 f –2.0 f ) M ⊙ , where f is the volume filling factor. We place SN 2014C in the context of 121 core-collapse SNe with evidence for strong shock interaction with a thick circumstellar medium. Finally, we highlight the challenges that the current mass-loss theories (including wave-driven mass loss, binary interaction, and line-driven winds) face when interpreting the wide dynamic ranges of CSM parameters inferred from observations.more » « less
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            null (Ed.)ABSTRACT We report on new Very Long Baseline Interferometry radio measurements of supernova (SN) 2014C in the spiral galaxy NGC 7331, made with the European VLBI Network ∼5 yr after the explosion, as well as on flux density measurements made with the Jansky Very Large Array (VLA). SN 2014C was an unusual SN, initially of Type Ib, but over the course of ∼1 yr, it developed strong H α lines, implying the onset of strong interaction with some H-rich circumstellar medium (CSM). The expanding shock-front interacted with a dense shell of circumstellar material during the first year, but has now emerged from the dense shell and is expanding into the lower density CSM beyond. Our new VLBI observations show a relatively clear shell structure and continued expansion with some deceleration, with a suggestion that the deceleration is increasing at the latest times. Our multifrequency VLA observations show a relatively flat power-law spectrum with Sν ∝ ν−0.56 ± 0.03, and show no decline in the radio luminosity since t ∼ 1 yr.more » « less
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