%0 Generic %1 graham2015possible %A Graham, Matthew J. %A Djorgovski, S. George %A Stern, Daniel %A Glikman, Eilat %A Drake, Andrew J. %A Mahabal, Ashish A. %A Donalek, Ciro %A Larson, Steve %A Christensen, Eric %D 2015 %K binary black-hole supermassive %R 10.1038/nature14143 %T A possible close supermassive black-hole binary in a quasar with optical periodicity %U http://arxiv.org/abs/1501.01375 %X Quasars have long been known to be variable sources at all wavelengths. Their optical variability is stochastic, can be due to a variety of physical mechanisms, and is well-described statistically in terms of a damped random walk model. The recent availability of large collections of astronomical time series of flux measurements (light curves) offers new data sets for a systematic exploration of quasar variability. Here we report on the detection of a strong, smooth periodic signal in the optical variability of the quasar PG 1302-102 with a mean observed period of 1,884 $\pm$ 88 days. It was identified in a search for periodic variability in a data set of light curves for 247,000 known, spectroscopically confirmed quasars with a temporal baseline of $\sim9$ years. While the interpretation of this phenomenon is still uncertain, the most plausible mechanisms involve a binary system of two supermassive black holes with a subparsec separation. Such systems are an expected consequence of galaxy mergers and can provide important constraints on models of galaxy formation and evolution.

@misc{graham2015possible, abstract = {Quasars have long been known to be variable sources at all wavelengths. Their optical variability is stochastic, can be due to a variety of physical mechanisms, and is well-described statistically in terms of a damped random walk model. The recent availability of large collections of astronomical time series of flux measurements (light curves) offers new data sets for a systematic exploration of quasar variability. Here we report on the detection of a strong, smooth periodic signal in the optical variability of the quasar PG 1302-102 with a mean observed period of 1,884 $\pm$ 88 days. It was identified in a search for periodic variability in a data set of light curves for 247,000 known, spectroscopically confirmed quasars with a temporal baseline of $\sim9$ years. While the interpretation of this phenomenon is still uncertain, the most plausible mechanisms involve a binary system of two supermassive black holes with a subparsec separation. Such systems are an expected consequence of galaxy mergers and can provide important constraints on models of galaxy formation and evolution.}, added-at = {2015-01-08T10:09:43.000+0100}, author = {Graham, Matthew J. and Djorgovski, S. George and Stern, Daniel and Glikman, Eilat and Drake, Andrew J. and Mahabal, Ashish A. and Donalek, Ciro and Larson, Steve and Christensen, Eric}, biburl = {https://www.bibsonomy.org/bibtex/2f5d4c383b06e87c142a59d5f0eef90f3/miki}, description = {[1501.01375] A possible close supermassive black-hole binary in a quasar with optical periodicity}, doi = {10.1038/nature14143}, interhash = {91f41637479fdb9588318eb44d335ece}, intrahash = {f5d4c383b06e87c142a59d5f0eef90f3}, keywords = {binary black-hole supermassive}, note = {cite arxiv:1501.01375Comment: 19 pages, 6 figures. Published online by Nature on 7 January 2015}, timestamp = {2015-01-08T10:09:43.000+0100}, title = {A possible close supermassive black-hole binary in a quasar with optical periodicity}, url = {http://arxiv.org/abs/1501.01375}, year = 2015 }