GG Carinae: Discovery of orbital phase dependent 1.583-day periodicities in the B[e] supergiant binary

GG Carinae is a binary whose primary component is a B[e] supergiant. Using photometric data from TESS, ASAS, OMC, and ASAS-SN, and spectroscopic data from the Global Jet Watch to study visible He\,I, Fe\,II and Si\,II emission lines, we investigate the short-period variations which are exhibited in GG Car. We find a hitherto neglected periodicity of $1.583156\pm0.0002$\,days that is present in both its photometry and the radial velocities of its emission lines, alongside variability at the well-established $\sim$31-day orbital period. We find that the amplitudes of the shorter-period variations in both photometry and some of the emission lines are modulated by the orbital phase of the binary, such that the short-period variations have largest amplitudes when the binary is at periastron. There are no significant changes in the phases of the short-period variations over the orbital period. We investigate potential causes of the 1.583-day variability, and find that the observed period agrees well with the expected period of the $l=2$ f-mode of the primary given its mass and radius. We propose that the primary is periodically pulled out of hydrostatic equilibrium by the quadrupolar tidal forces when the components are near periastron in the binary's eccentric orbit ($e=0.5$) and the primary almost fills its Roche lobe. This causes an oscillation at the $l=2$ f-mode frequency which is damped as the distance between the components increases.Comment: Accepted for publication in MNRAS. 14 pages, 14 figure

The complete illustrated guide to Niagara Falls and vicinity. -

Attributed to Peter Augustus Porter--National Union Catalog, pre-1956 imprints

A brief history of Old Fort Niagara /

Running title: Old Fort Niagara in history.Mode of access: Internet

Frederick A. P. Barnard letter and speech, MSS.0113

Abstract: An address to the "Gentlemen of the Erosophic Society" in 1848 at The University of Alabama and a letter to Barnard from his brother, John G. Barnard, regarding a pass for travel in 1862.Scope and Content Note: An address to the "Gentlemen of the Erosophic Society" in 1848 at The University of Alabama and a letter to Barnard from his brother, John G. Barnard, regarding a pass for travel in 1862.Biographical/Historical Note: Frederick Augustus Porter Barnard was born in Sheffield, Massachusetts, in May 1809. A graduate of Yale University in 1828, he joined The University of Alabama faculty in 1837, where he taught mathematics, chemistry, natural sciences, and philosophy until 1854, when he left for the University of Mississippi. He was chancellor of the University of Missississippi from 1856 until the beginning of the Civil War, when he returned to the North. He was president of Columbia College (Columbia University) from 1864 until the late 1870s, shortly before his death in 1879. Barnard supported women's education, and Barnard College was named in his honor

Correspondence : Barnard (Frederick) and Engelmann (George), 1864.

Barnard to Engelmann, 186

Letter to the honorable, the Board of trustees of the University of Mississippi.: By Frederick A. P. Barnard ...

112 p ; 23cm.Electronic text and image data. Ann Arbor, Mich. : University of Michigan, Digital Library Initiatives, 1996. Includes both TIFF files and keyword searchable text. [Making of America] This volume is made possible by a grant from the Andrew W. Mellon Foundation

The metric system of weights and measures; an address delivered before the convocation of the University of the State of New York, at Albany, August l, l871; by Frederick A. P. Barnard.

3 p. l., [3]-194 p. 23 1/2 cm