NOVA AQUILAE 1918 (V603 Aql) FADED BY 0.44 MAG PER CENTURY FROM 1938 TO 2013

• Published in: Astrophysical journal. Letters Vol. 780; no. 2; pp. 1 - 4
• Main Authors: Johnson, Christopher B, Schaefer, Bradley E, Kroll, Peter, Henden, Arne A
• Format: Journal Article
• Language: English
• Published: United States 10.01.2014
• Subjects: AQL; ASTROPHYSICS; ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BRIGHTNESS; DIAGRAMS; ERRORS; ERUPTION; Fading; FORECASTING; Hibernation; Light curve; MASS; Mathematical models; Nova; NOVAE; PLATES; STAR EVOLUTION; TRANSFORMATIONS; Variable stars; VISIBLE RADIATION
• ISSN: 2041-8205; 2041-8213
• DOI: 10.1088/2041-8205/780/2/L25

We present the light curve of the old nova V603 Aql (Nova Aql 1918) from 1898-1918 and 1934-2013 using 22, 721 archival magnitudes. All of our magnitudes are either in, or accurately transformed into, the Johnson B and V magnitude systems. This is vital because offsets in old sequences and the visual-to-V transformation can cause errors of 0.1-1.0 mag if not corrected. Our V603 Aql light curve is the first time that this has been done for any nova. Our goal was to see the evolution of the mass accretion rate on a century timescale, and to test the long-standing prediction of the Hibernation model that old novae should be fading significantly in the century after their eruption is over. The 1918 nova eruption was completely finished by 1938 when the nova decline stopped, and when the star had faded to fainter than its pre-nova brightness of B = 11.43 + or - 0.03 mag. We find that the nova light from 1938 to 2013 was significantly fading, with this being seen consistently in three independent data sets (the Sonneberg plates in B, the American Association of Variable Star Observers (AAVSO) V light curve, and the non-AAVSO V light curve). We find that V603 Aql has been declining in brightness at an average rate of 0.44 + or - 0.04 mag per century since 1938. This work provides remarkable confirmation of an important prediction of the Hibernation model.