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arXiv · 2202.08365

Investigating the low-flux states in six Intermediate Polars

Ava E. Covington·Aarran W. Shaw·Koji Mukai·Colin Littlefield·Craig O. Heinke·Richard M. Plotkin·Doug Barrett·James Boardman·David Boyd·Stephen M. Brincat·Rolf Carstens·Donald F. Collins·Lewis M. Cook·Walter R. Cooney·David Cejudo Fernández·Sjoerd Dufoer·Shawn Dvorak·Charles Galdies·William Goff·Franz-Josef Hambsch·Steve Johnston·Jim Jones·Kenneth Menzies·Libert A. G. Monard·Etienne Morelle·Peter Nelson·Yenal Öğmen·John W. Rock·Richard Sabo·Jim Seargeant·Geoffrey Stone·Joseph Ulowetz·Tonny Vanmunster
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Abstract

We present optical photometry of six intermediate polars that exhibit transitions to a low-flux state. For four of these systems, DW Cnc, V515 And, V1223 Sgr and RX J2133.7+5107, we are able to perform timing analysis in and out of the low states. We find that, for DW Cnc and V515 And, the dominant periodicities in the light curves change as the flux decreases, indicating a change in the sources' accretion properties as they transition to the low state. For V1223 Sgr we find that the variability is almost completely quenched at the lowest flux, but do not find evidence for a changing accretion geometry. For RX J2133.7+5107, the temporal properties do not change in the low state, but we do see a period of enhanced accretion that is coincident with increased variability on the beat frequency, which we do not associate with a change in the accretion mechanisms in the system.

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Ava E. Covington, Aarran W. Shaw, Koji Mukai, Colin Littlefield, Craig O. Heinke, Richard M. Plotkin, Doug Barrett, James Boardman, David Boyd, Stephen M. Brincat, Rolf Carstens, Donald F. Collins, Lewis M. Cook, Walter R. Cooney, David Cejudo Fernández, Sjoerd Dufoer, Shawn Dvorak, Charles Galdies, William Goff, Franz-Josef Hambsch, Steve Johnston, Jim Jones, Kenneth Menzies, Libert A. G. Monard, Etienne Morelle, Peter Nelson, Yenal Öğmen, John W. Rock, Richard Sabo, Jim Seargeant, Geoffrey Stone, Joseph Ulowetz, Tonny Vanmunster. 2022-02-19. Investigating the low-flux states in six Intermediate Polars. https://doi.org/10.3847/1538-4357%2Fac5682

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