Nova Aquilae 1943
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Double star Nova Aquilae 1943 |
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| AladinLite | |||
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Observation dates equinox : J2000.0 , epoch : J2000.0 |
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| Constellation | Eagle | ||
| Right ascension | 19 h 52 m 27.84 s | ||
| declination | + 08 ° 28 ′ 46.4 ″ | ||
| Apparent brightness | 17.8 mag | ||
| Typing | |||
| Spectral class | Q | ||
| Variable star type | N / A | ||
| Astrometry | |||
| Radial velocity | -75.0 km / s | ||
| Physical Properties | |||
| Rotation time | 3.48 h | ||
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Other names and catalog entries |
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Nova Aquilae 1943 or V500 Aquilae was a very fast nova of the NA type that appeared in the constellation Eagle in 1943 and reached a brightness of 6.1 m . Its brightness decreased by 3 m in 30 days .
This nova experienced little observation time. The rather incomplete light curve of the outbreak (e.g. Payne-Gaposchkin, 1957) nevertheless allowed it to be classified as a medium-fast nova (t3 = 42 days) of the Na type. After reaching the maximum photographic brightness of about 6.1 m, the system faded to 17.8 m . The distance could be determined to be 4.9 k pc . From a spectrum that was recorded about 170 days after the maximum, the expansion rate could be derived as about 2,800 km / s. Based on the occurrence of [Ne III] and [Fe VII] lines in this spectrum, it was suggested that this nova should be classified in the He / N class (Della Valle and Livio 1998).
A spectrogram of Nova Aquilae 1943 from λ 3869 Å to Hα was made with the 100-inch reflector and the two-prism spectrogram on October 11, 1943, when the strength of the Nova was still about 13 m . The scatter was 115 Å / mm for Hγ and 470 Å / mm for Hα. The mean width of all lines was determined to be 2760 km / s or 40 Å at Hγ. The broad emission lines are more intense at their edges than in their central parts, with the central minimum in λ 5755 Å being so pronounced that it divides the line in half.
Three separate measurements of the radial speed gave values of -55, -75 and -95 km / s. The -75 km / s mean is likely less accurate than the range suggests. No continuous spectrum was recorded.
Further photometric observations were made in August 1994 with the CCD camera of ESO 's Dutch 90 cm telescope, which has since been decommissioned . Since the star looked very faint (approx. 20 m ), the measurements were carried out as integral images of the spectrogram. All of this suggests that Nova Aquilae was likely at the beginning of a ( dwarf nova) outbreak in 1943, behavior that was observed in a few more classic novas. Unfortunately, the nocturnal data from the second observation suffered from even worse weather conditions, which leads to a greater spread. After taking into account the difference of 0.15 m , the combined data set was subjected to a time series analysis, which resulted in a rotation time of 3.485 ± 0.02 hours. No more detailed parameters could be derived from the present data set, but it was sufficient to demonstrate the phenomenon of cover in the Nova Aquilae 1943 system.
Individual evidence
- ↑ a b NOVA Aql 1943. In: SIMBAD . Center de Données astronomiques de Strasbourg , accessed on March 29, 2019 .
- ↑ a b c d V0500 Aql. In: VSX. AAVSO , accessed March 29, 2019 .
- ↑ Novae. In: Eberfing Observatory. 2018, accessed March 17, 2019 .
- ^ A b Haefner, R. V500 Aql: AN Eclipsing Classical Nova In: Information Bulletin on Variable Stars, No. 4706, # 1. Haefner, R. 05/1999. bibcode : 1999IBVS.4706 .... 1H .
- ^ Sanford, Roscoe F .: The Spectrum of Nova Aquilae 1943 Publications of the Astronomical Society of the Pacific, Vol. 55, No. 327, p.284, 12/1943 doi : 10.1086 / 125575 .