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arXiv · 2608.20461

Investigating the Multiwavelength Emission of Binary SMBH Candidate SDSS J095036.75+512838.1

Cassandra Daniele·Adi Foord·Jessie Runnoe·Michael Eracleous·Niana N. Mohammed
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Abstract

We present results from a multiwavelength study of the binary AGN candidate SDSS J095036.75+512838.1, which was identified as a candidate binary SMBH system due to its significant and variable broad H$β$ line shifts. We use available infrared-to-X-ray data to investigate the system's accretion properties. Analyzing recent Chandra observations, we characterize the X-ray emission and test the binary SMBH hypothesis. We find that the X-ray spectrum is well-modeled as a single AGN, with a 2--10 keV luminosity of $1.3 \times10^{43}$ erg s$^{-1}$. By assembling a comprehensive multiwavelength spectral energy distribution, we further examine the possibility of circumbinary accretion. The infrared-optical emission matches that expected from a single AGN, though we observe an excess in emission between $\sim 9500-19000 Å$ and a deficit near $\sim 2600 Å$. Archival optical spectra also suggest a deficit near $\sim 8500 Å$. We investigate whether these SED anomalies can be explained by long-term variability or interstellar reddening. We find no evidence of dimming, while reddening can account for the deficit in UV emission. However, the origin of the near-infrared excess remains unclear. Ultimately, the SED of SDSS J095036 is well described by emission from a single, reddened AGN. Future high-resolution infrared and X-ray spectral observations will be crucial for disentangling the origin of the infrared excess and testing the binary SMBH scenario in SDSS J095036.

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Cassandra Daniele, Adi Foord, Jessie Runnoe, Michael Eracleous, Niana N. Mohammed. 2026-08-20. Investigating the Multiwavelength Emission of Binary SMBH Candidate SDSS J095036.75+512838.1. https://arxiv.org/abs/2608.20461

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